Design and Implementation of a Microcontroller Based Forced Air Egg Incubator · 2020-02-03 ·...

Design and Implementation of a Microcontroller Based Forced Air Egg Incubator

Muhammad Anowar Kabir

DEPARTMENT OF ELECTRICAL AND ELECTRONIC ENGINEERING

DHAKA UNIVERSITY OF ENGINEERING AND TECHNOLOGY, GAZIPUR


Muhammad Anowar Kabir



December 2014




Design and Implementation of Forced Air Egg Incubator

submitted to the Department of Electrical and Electronic Engineering, DUET in the partial fulfillment of the requirements for the award of the degree

Electr

Prof. Dr. Md. Anwarul Abedin




A project report submitted to the Department of Electrical and Electronic Engineering, DUET in the partial

fulfillment of the requirements for the award of the degree

of

Master of Engineering in

Electrical and Electronic Engineering

By

Muhammad Anowar Kabir Student No.: 102211-P

Under Supervision of

Prof. Dr. Md. Anwarul Abedin

Head, Department of EEE


UNIVERSITY OF ENGINEERING AND TECHNOLOGY, GAZIPUR

December 2014

Microcontroller Based

submitted to the Department of Electrical and Electronic Engineering, DUET in the partial fulfillment of the requirements for the award of the degree


UNIVERSITY OF ENGINEERING AND TECHNOLOGY, GAZIPUR

i

Declaration

I hereby declare that this project is my own work and has not been

submitted elsewhere for the award of any degree or diploma.

Signed: ……………………………………………………..

Date: ……………………………………………………..

ii

Acknowledgements

In this very moment, I would like to express my gratitude to the almighty Allah for

His blessing on me to complete this work successfully. I would like to extend my deepest

gratitude to all who have helped me in one way or another to finish the work at hand, this

dissertation.

I am greatly thankful to my supervisor Prof. Dr. Md. Anwarul Abedin for his

unending support throughout my M. Engineering study. For his students, he has always

taught to never forget that hard work is the only way to success. Without his continuous

monitoring, encouragement and tolerance to numerous mishaps, I could not have successfully

completed this work.

I am grateful to Prof Dr. Md. Shahid Ullah Head, EEE Department Islamic University

of Technology (IUT) for providing the facilities and advice in carrying out the study, and the

encouragement for the completion of this project. I am grateful to Jose Neuca, Incubator Repair and Fabrication, 12897 Antipas,

Mayondon Los Banos Laguna, Phylippins-4030 was always helpful and share his practical

experience of Egg Incubator and offered continuous support for my project works. Special

thanks and appreciations are due to the Faculty of Animal Husbandry, Bangladesh Agricultural

University, Mymensingh - 2202, Bangladesh, Poultry Rearing and Farming Department,

Technical School and College, Gazipur and poultry farmers in the study areas who provided the

relevant information for preparing this thesis. I want to thank all staff of my Indigenous

Technology Research and Development Laboratory, M A Aziz Peace Institute of

Technology, Gazipur for supporting me in building the hardware and test incubation

processes.

My deepest gratitude goes to my wife for her unflagging love and support throughout

my life. I would like to acknowledge the sacrifice and love of my parents. My father Md.

Abdul Aziz very helpful in fabricating and constructing the casing and egg turning system.

At last, I would like to thank to all the members of Department of Electrical and

Electronic Engineering Dhaka University of Engineering and Technology, Gazipur whose

love and affection made my course a memorable. I cannot forget the memories of each of the

moments during my study at DUET.

iii

Abstract

Incubation of eggs is an old process, but the act of incubation using the artificial

method is developing day by day. Creating an efficient incubator at a moderate and

affordable price is challenging because egg embryos (the developing chick in an egg) are

delicate, even a slight change of temperature, humidity and ventilation can affect the timing

of the hatchings, likewise a rough turning of the egg can kill the embryo. Commercial and

imported incubators available in the market are far greater in size than requirement of small

villages and costly. To acquire the goal of “One Home is One Farm”, it is present demand to

design low cost full function automatic high efficiency domestic incubator and to modernize

present mini-hatchery technology. The purpose of this project is to design, construct and

implement microcontroller based low cost universal domestic incubator which is able to

incubate different types of eggs and to modernize present mini-hatchery technology using

locally available material and resource to achieve a cost effective design.

The control unit is designed for monitoring and control the main incubation

parameters, like: temperature, humidity, ventilation (to control oxygen and carbon dioxide

level and air velocity), position of eggs and turning of eggs fulfills effective way as natural

incubation by using sensors and associated devices.

User friendly Human Machine Interfacing Menu Program (HMIMP) is implemented.

A twenty character by four lines liquid crystal display (LCD) allows the user to visualize

settings during configuration and the system status during operation. The implemented

control unit was tested in the laboratory as well as in the field.

The incubator combines the Setter and Hatcher together. The incubator can incubate

up to 120 eggs at a time. The incubator takes about 22 minutes to reach its Set Temperature

(from 22°C to 37.5°C). At that time it consumes 207 Watts. It consumes 69 Watts or

less after reaching its Set Temperature. It consumes approximately 35 kWh (kilowatt-hour)

electric powers for chick (21 days) incubation. It has automatic egg turning system, and alarm

on the high and low temperature and humidity.

It has advanced auto saving data log facility in excel which is very useful and realistic

for getting right prediction from output result to improve incubator operation for optimum

performance. This incubator can be used as educational egg incubator for Agricultural

School, college, institute, university and other research institutes and laboratory.

Contents

Declaration i

Acknowledgements ii

Abstract iii

List of Figures vii

List of Tables xi

1 Introduction 1 1.1 Background and Justification 1

1.2 Problem Statement 7

1.3 Aims and Objectives 8

1.4 Expected Benefits 9

1.5 Project Report Layout 10

2 Egg Incubation and Embryology 12 2.1 Introduction 12

2.2 Natural Incubation 12

2.3 Artificial Incubation 15

2.4 Egg Embryology 16

2.5 Important Incubation Factors Required to Maintain for Designing a

Successful Egg Incubator

17

2.5.1 Temperature 18

2.5.2 Eggs Position and Turning of eggs 24

2.5.3 Humidity 27

2.5.4 Ventilation and Oxygen Availability 34

2.5.5 Sanitation 35

Contents

v

2.6 Length of Incubation 37

2.7 Monitoring of Eggs and the Incubator 40

2.8 Different Types of Egg Incubators 41

2.9 Size of Incubator 42

2.10 Incubator Construction and Function 43

2.10.1 Still Air Incubators 43

2.10.2 Forced-Air Draft Incubators 44

3 Design of a Microcontroller Based Forced Air Egg Incubator 46 3.1 Introduction 46

3.2 Incubator Design Considerations and Implementation 46

3.3 Mechanical Structure Design of the Incubator 48

3.3.1 Incubator Casing 48

3.3.2 Heating Element and Heating Cable 52

3.3.3 Egg Setter Tray 52

3.3.4 Tray Supports 52

3.3.5 Egg Tray Turning Mechanism 53

3.3.6 Egg Hatcher Tray 54

3.3.7 Circulating Fan 54

3.3.8 Ventilation System 54

3.3.9 Water Supply and Water Pans 54

3.4 Embedded System Design of the Incubator 55

3.4.1 Electronic Hardware Design 56

3.4.1.1 The Microcontroller Unit (MCU) 56

3.4.1.2 The Sensor Unit 58

3.4.1.3 The Real Time Clock (RTC) Unit 69

3.4.1.4 The User Interface 72

3.4.1.5 Auto Saving Data Logging in MS Excel 75

3.4.1.6 The Driver Unit 76

3.4.1.7 The Power Supply Unit 78

3.4.1.8 Overall Circuit Diagram of the Incubator 80

3.4.1.9 IR Remote Control for Egg Turning System 82

Contents

vi

3.4.2 Software Development 84

3.4.2.1 Main Program Flow of the System 84

3.4.2.2 Block Diagram for Menu Program 85

3.4.2.3 DS18B20 Temperature Sensors Read and Process Sub-program 87

3.4.2.4 LM35 Temperature Sensors Read and Process Sub-program 87

3.4.2.5 Humidity Sensors Read and Process Sub-Program 87

3.4.2.6 Temperature Control Sub-Program 87

3.4.2.7 Humidity Control Sub-Program 90

3.4.2.8 Egg Turning Control Sub-Program 90

3.4.2.9 Ventilation Control and Alarm System Sub-Program 90

3.4.2.10 IR Remote Control Transmitter 91

3.4.2.11 IR Remote Control Receiver 91

3.4.2.12 Program Coding 91

3.4.2.13 Chips Programming 91

3.5 PCB Design, Fabrication and Electrical Wiring 92

3.5.1 MBFAEIC Motherboard 92

3.5.2 PC Interface Card 93

3.5.3 Relay Driver Card 94

3.5.4 Fabrication MBFAEI Controller Unit 95

3.5.5 Electrical Wiring 96

4 Test Hatching and Performance Analysis 98 4.1 Introduction 98

4.2 Incubation of Eggs in Incubator (MBFAEI) 100

4.3 The Incubator (MBFAEI) Hatching Tests and Performance Analysis 112

5 Conclusion and Recommendation 116 5.1 Conclusion 116

5.2 Recommendation 118

References 119

Appendices 124

List of Figures

Fig. No. Caption Page

1.1 Egyptian Incubator …………...……………………..………………..…….. 03

1.2 A Chinese Incubator (From the Journal “The Baby Chick”) ………….……. 04

1.3 Rice Husk Method, Mini-hatchery PKSF/IFAD ………………………….. 05

1.4

Sand Method, Mini-hatchery PKSF/IFAD …………………………….…... 06

2.1 Birds Nest Engineering for Proper Incubating Environment ……………… 14

2.2 Heat Production of Incubating Eggs ……………………………………… 17

2.3 Five Incubation Temperature Zones for Chicken Eggs …………………… 19

2.4 The Proper Orientation of the Egg During Incubation ………………..…… 24

2.5 Egg Tray Turning Method ……………………………………………… 26

2.6 Optimum Weight Loss of Eggs during Incubation ...……………………… 29

2.7 The Growth of Air Cell during the Incubation …….……………………… 32

2.8 The Average Actual Weights of Incubating Eggs against the Ideal Weight

Loss Line …………………………………………………………………...

33

2.9 Candler (a) Candler using Light Bulb, (b) Candler using Torch ………… 41

2.10 Still-air Egg Incubator ………………………………………………… 43

2.11

Forced-air Draft Incubator ………………………………………………….. 44

3.1 Microcontroller Based Forced Air Egg Incubator Implementation Flow Chart. 47

3.2 Microcontroller Based Forced Air Egg Incubator Prototype ……………….. 49

3.3 Typical View of the Incubator Casing During Construction Process ………. 50

3.4 Insulation Layer in Between Plywood ……………………………………… 51

3.5 Typical View of Door with Glass Window …………………………………. 51

3.6 Egg Tray ……………………………………………………………………. 52

List of Figures

viii


3.7 Tray Supports ………………………………………………………………. 53

3.8 Egg Tray Turning Mechanism ……………………………………………… 53

3.9 Microcontroller Based Forced Air Egg Incubator Controller Block Diagram 55

3.10 PIC16F877A Microcontroller (a) Physical Layout (b) Pin Configuration .. 57

3.11 PIC16F877A Internal Block Diagram ……………………………………… 59

3.12 LM35Voltage Output Temperature Sensor ………………………………… 61

3.13 DS18B20 Digital Output Temperature Sensors ………………………….. 62

3.14 DS18B20 Detail Pin Description …………………………………………… 62

3.15 DS18B20 Block Diagram …………………………………………………… 63

3.16 DS18B20 Typical Connection ……………………………………………. 63

3.17 Physical Sensor Connection ……………………………………………… 64

3.18 DS18B20 Memory Map …………………………………………………… 64

3.19 Temperature/Data Relationship …………………………………………… 65

3.20 DS18B20 Initialization Timing …………………………………………… 65

3.21 HSM20G Humidity Sensor (a) Front View , (b) Back View ……………… 67

3.22 Relative Humidity Response of HSM-20G ……………………….………... 67

3.23 Physical Sensor Connection (HSM20G) ………………………………… 68

3.24 DS1302 Pin Diagram ………………………………………………………. 69

3.25 Wiring Diagram for the DS1302 …………………………………………… 70

3.26 Typical PC Board Layout for Crystal …………………………………….. 71

3.27 Register Address / Definition ……………………………………………….. 72

3.28 Human Machine Interfacing Push Buttons Control Circuitry ………………. 73

3.29 The Switch Contacts Bounce ………………………………………………. 74

3.30 The Ideal Waveform of Switch Contact ……………………………………. 74

3.31 Signal as it Leaves the PIC Pin (The PIC Side of the MAX232) ………… 76

3.32 Signal on an RS232 Line (The PC Side of the MAX232) ………………… 76

3.33 RS232 Data Logger Circuit …………………………………………………. 76

3.34 Buzzer Circuit ……………………………………………………………… 77

3.35 Interfacing Relay with Microcontroller ………………………………….… 77

3.36 Interfacing Relay with Microcontroller using Opto-Isolator ……………… 78

3.37 Independent +5V Regulated Power Supply ……………………………… 78

List of Figures

ix


3.38 Independent +12V Regulated Power Supply ...…………………………… 79

3.39 Overall Circuitry of the MCBFAEI (Part-1) ……………………………… 80

3.40 Overall Circuitry of the MCBFAEI (Part-2) ……………………………… 81

3.41 IR Remote Control Transmitter and Receiver System ……………………… 82

3.42 Modulation of SIRC Protocol ………………………….…………………… 82

3.43 SIRC Protocol Signal Pattern ……………………………………………… 83

3.44 Main Program Flow of the Incubator ………………………………………. 84

3.45 Human Machine Interfacing Menu Program (HMIMP) Operation (Part 1) .. 85

3.46 Human Machine Interfacing Menu Program (HMIMP) Operation (Part 2) .. 86

3.47 Temperature Control Sub-Program ………………………………………… 89

3.48 Humidity Control Sub-Program …………………………………………… 90

3.49 MBFAEIC Motherboard (Bottom Copper View) ………………………….. 92

3.50 MBFAEIC Motherboard (Top View) …………………………………….… 92

3.51 MBFAEIC Motherboard (3D Visualization using ARES Professional) ……. 93

3.52 PC Interface Card (Top View, Bottom Copper View and 3D visualization) 93

3.53 Relay Driver Card (Top View and Bottom Copper View) ………………… 94

3.54 Relay Driver Card (3D Visualization) …………………………………….. 94

3.55 Relay Driver Card with Opto-Isolator (Top View, Bottom Copper View and

3D Visualization) ……………………………………………………………

94

3.56 MBFAEIC Housing of the PCB Cards …………………………………….. 95

3.57 MBFAEI Controller in Operation (Data Logging) …………………………. 95

3.58 Electrical Wiring of Egg Turning Motor, Ventilation and Humidity Control

System ……………………………………………………………………...

96

3.59

Electrical Wiring of Four Heating Elements ……………………………… 97

4.1 The Incubators Normal Run and Operation Mode Display Information ….. 98

4.2 Fumigation of Hatching Eggs …………………………………….………… 100

4.3 Egg Storage ………………………………………………………………… 101

4.4 Loading of Hatching Eggs to Setter Tray …………………………………… 102

4.5 Eggs are Transferred to Hatcher Tray ……………………………………. 109

4.6 Successfully Hatched DOCs (Day Old Chicks) ………………………… 110

4.7 Steps Involved in Successfully Egg Incubation Operations ………………… 111

4.8 The Incubator (MBFAEI) Hatched Chicks-1 ……………………………… 112

List of Figures

x


4.9 The Incubator (MBFAEI) Hatched Ducks …………..…………………… 112

4.10 The Incubator (MBFAEI) Hatched Chicks-2 ……………………………… 113

4.11 The Incubator (MBFAEI) Hatched (Multistage) Coturnix Quail ………… 113

4.12 The Incubator (MBFAEI) Hatched (Multistage) Chicks-3 ………………… 114

4.13 Coturnix Quail and Indigenous Chicks Intensive Rearing ………………….. 114

4.14 Implemented Incubators ………………………………………………….. 115

xi

List of Tables


2.1 The Incubation Period and Incubator Operation for Common Domestic Birds (Part-1) 38

2.2 The Incubation Period And Incubator Operation For Common Domestic Birds (Part-2) 39

2.3

The Advantages and Disadvantages the Still-Air and the Forced-Air Incubator 45

3.1 Internal and External Dimensions of the Incubator ……………………….. 49

3.2 Egg Setter Tray Dimension ………………………………………………… 52

3.3 Relative Humidity Verses Output Voltage Relation ………………………. 68

Chapter 1

Introduction

1.1 Background and Justification

Bangladesh is the biggest delta landscape in the world with a large human and

natural resources [1]. Over 74% of the total population lives in rural areas and they are

dependent on agriculture [2] for their livelihood. Agriculture is one of the most important

segments in Bangladesh and growth and sustainability of agricultural production are

prerequisite for attaining the rate of overall growth of the economy. Agriculture sector

plays an important role in the overall economic development of Bangladesh and it is

regarded as the lifeline of Bangladesh economy. It is also an important social sector

concerned with some issues like food and nutritional security, income generation, and

poverty reduction. The increasing ratio of eggs, meat and milk production is considered as

a good sign and a step for the improvement of our nation’s health nutrition. The

agriculture sector in Bangladesh is gradually diversifying in favor of high-value

commodities, mainly fruits, vegetables, livestock, poultry and fish products. After

readymade garment sector, poultry farming has turned out to be promising dynamic

enterprise with enormous potential for rapid poverty reduction in Bangladesh. Poultry

enterprise is also most vital due to its contributions to national economy in sphere of

generation of local income-employment creation and improving the nutrition level of third

world country like Bangladesh. The term “poultry” applies to a rather wide variety of birds

of several species. Men’s can get financial benefit from those kinds of birds and the birds

reproduce with the care of man is called poultry. Chickens, ducks, geese, Guinea fowl,

pigeon, turkeys etc. are generally considered as poultry birds [3-4]. Poultry industry is one

of the major among livestock sub-sectors that committed to supply cheap sources of good

Chapter 1. Introduction

2

quality nutritious animal protein to the nation. Poultry meat contributes approximately

37% of the total animal protein in our country [5].

People in our country raise poultry mainly with a view to get meat and egg to

fulfill their day to day consumption. Poultry meat and egg holds an important position in

our daily diet. The per capita consumption of all meat is 14.67 Kg and that of egg is 31

numbers as against the requirements of 56 Kg meat and 365 eggs, respectively [6].

Approximately 70% people in our country are suffering from malnutrition and 81%

families don’t get calories according to their needs [3-4]. Malnutrition is caused for the

lacking of protein. The worst victims of malnutrition of this country are usually the

children and the women. A large portion of children are suffered from anemia and

underweight for lacking of nutrition. Today the concept of human nutrition has taken a

new dimension. The emphasis has been given on high protein and low calorie diet, as

protein plays a vital role in the balanced and health growth of human being. Poultry is a

great source of protein by providing eggs and meat. It provides palatability and is a good

source of essential amino acids, vitamins and minerals. Poultry meat shared second

position of the meat production. In this circumstance, poultry appears to be a good way of

meeting the protein gap by providing eggs and meat with low cost. The price of poultry

meat is comparatively lower than other livestock like beef, muttons meat and others.

With the unfavorable land-man ratio accompanied by unexpectedly high growth

rate of population, the number of disguised unemployed manpower in the country is

increasing day by day. About 31.5% people live under poverty line in our country [7].

Profitable intensive poultry rearing can play a vital role in Bangladesh because the

landless people and owner of low land in our country can easily rear intensive poultry

through of the limitation of land scarcity. It is difficult to set up commercial dairy or goat

farm in a large scale to fulfill the protein demand.

Egg incubator plays an important role in the overall poultry production system

especially during the day old chick development. In Bangladesh, poultry production is a

lucrative business but lack of commercially owned hatchery machines hinder the

expansion and make poultry products for instance day old chicks costly more especially in

the remote village area of Bangladesh. A part of the disguised unemployed people can be

employed with the family poultry development and production business by producing their


3

own DOC (Day Old Chick) in their own egg incubator, to reduce the present DOC and

hatching egg problem.

An egg incubator is a piece of equipment that creates the perfect conditions for an

egg to incubate. Successful incubation environment depends on maintaining favorable

conditions for hatching fertile eggs. Temperature, Humidity, Ventilation (for oxygen,

carbon dioxide and the internal pH) and Turning frequency during the incubation period

markedly affect the hatchability of fertile eggs and chick quality [8].

Figure 1.1: Egyptian Incubator

The artificial incubation technology was in practice in Egypt thousand years before

Christ. The men who built the pyramids also built incubators. The design and construction

of Egyptian Incubator shown in Figure 1.1 [9], these hatcheries were ingenious, but

simple. The eggs lay on the floor of a cylindrical, brick building. Two to three feet above

the eggs was a trough-like platform encircling the inner wall, within which burned a

perpetual fire of camel dung. Air was drawn in through an opening at ground level,

passed through the central hole in the ring of fire, and out through a hole in the dome-


shaped roof. Double rows of these incubating ovens faced on to a central corridor.

Openings in the roof and ends of this corridor admitted light and ventilation. Th

temperature of the eggs was measured by placing them against the eye

by stoking or raking the fires. Humidity requirements and air cell size were judged by the

sound made by rolling two eggs together in one hand.

The Egyptians did not, however, have a monopoly on egg hatching. Their Chinese

counterparts had developed two very successful methods by at least 1,000 B.C. The

and simplest, used the heat of rotting manure. The eggs were placed in a mixture of

chopped straw and rice hulls on top of the manure; it appears to have been moderately

successful. The second method, more widely used and still functional today, was just as

ingenious as the Egyptian hatchery. The basic structure was again a cylindrical building,

but the fire was on the floor, with the eggs contained in an inverted cone above it, partially

filled with ashes. Placed on the ashes were egg baskets made of woven straw. The eggs

were contained in muslin bags, the whole being covered in an insulating layer of rice hu

A straw thatch roof, shaped like the traditional coolie's hat, completed the insulation, and

kept out the rain. The Figure 1.2 shows a Chinese incubator found in the journal The Baby

Chick.

Figure 1.2: A Chinese I

Every seven days a fresh bag of eggs was added to each basket, and the bags were

continually moved about to turn the eggs. After the first three weeks of the hatching

season, the fire was allowed to go out; the self

going. They had also developed the art of candling, for clear eggs were removed on the

third day and sold for normal consumption.

4


Openings in the roof and ends of this corridor admitted light and ventilation. Th

temperature of the eggs was measured by placing them against the eye-


sound made by rolling two eggs together in one hand.

not, however, have a monopoly on egg hatching. Their Chinese

counterparts had developed two very successful methods by at least 1,000 B.C. The


e hulls on top of the manure; it appears to have been moderately

method, more widely used and still functional today, was just as


was on the floor, with the eggs contained in an inverted cone above it, partially


were contained in muslin bags, the whole being covered in an insulating layer of rice hu



A Chinese Incubator (From the Journal “The B



season, the fire was allowed to go out; the self-generative heat of the eggs


third day and sold for normal consumption.


Openings in the roof and ends of this corridor admitted light and ventilation. The

-lids, and controlled


not, however, have a monopoly on egg hatching. Their Chinese

counterparts had developed two very successful methods by at least 1,000 B.C. The first,


e hulls on top of the manure; it appears to have been moderately

method, more widely used and still functional today, was just as


was on the floor, with the eggs contained in an inverted cone above it, partially


were contained in muslin bags, the whole being covered in an insulating layer of rice hulls.



The Baby Chick”)



generative heat of the eggs kept the process



5

The Greeks were not to be outdone, for Aristotle described in detail a method using

rotting manure in 400 B.C. Several records exist of high-born Roman ladies foretelling the

sex of their offspring by hatching an egg tucked under their breasts. Numerous

descriptions of methods using the heat of the human body are recorded throughout history

and from all over the world. Philippine islanders paid their servants to lie on eggs. The

eggs were laid between rows of sticks on a bed of ashes, and both servant and eggs were

covered with blankets. South African farmers employed native girls to hatch ostrich eggs

with body heat, when the feathers of these birds were in terrific demand. Over the year’s

incubators have been refined and developed so they are almost completely automatic.

Mini-hatcheries have been in use in Bangladesh since the 1970s. In 1992, BRAC

has taken up a program on Rice Husk Incubator in various parts of Bangladesh. It is

named as “Rice husk method of incubation” because the rice husk is used as the main

ingredient (element) to insulate against heat loss [10]. However, the system was not

widely adopted, largely because of poor management of fertile eggs in the supply chain.

The Palli Karma Sahayak Foundation (PKSF) has led the implementation of the IFAD

funded Microfinance and Technical Support Project (MFTSP) across 97 sub-districts in

southern and north-eastern Bangladesh, in partnership with other NGOs to adopting a

mini-hatchery techniques as an income generating activities of their beneficiaries. Mini-

hatchery becomes popular among the rural peoples of Kishoregonj, Hobigonj and Sylhet

district of Bangladesh for its low installation and management cost and high benefit.

Rural peoples of various part of Bangladesh are using three types of mini-

hatcheries like Rice Husk method, Rice Husk & Quilt method and Sand method, which are

modified Chinese incubator. For rice husk incubation technique, the items needed are:

incubation room, incubation box, incubation cylinder, hatching bed, petrol lamp,

thermometer, bamboo tray, color cloth, candling box and rice husk. For sand incubation

technique, the items needed are: incubation box, tray (made with net), thermometer, lamp

(hurricane), water pot, and sand.

In Rice Husk Incubation Technique in shown Figure 1.3 [11], the bamboo made

incubation box and two (or three) cylinders (which are also bamboo made) are needed to

be set up in a dark room (incubation room), possibly well insulated. The cylinders are

placed in a central point. Then the incubation chamber should be filled up with rice husk.


6

A petrol lamp (Hurricane) should always be kept in one cylinder alternately during the

entire hatching period to keep the chamber warm up to 98-100° F or 37-38°C.

(a) Incubation cylinder (Bamboo) placed inside the rise husk filled Incubation box, along with the thermo-meter Incubation cylinder heated with kerosene lamp.

(b) A poultry rearer heating the eggs on a bamboo strainer to putting them in the Incubation cylinders.

(c) An incubation box housing three incubation cylinders.

Figure 1.3: Rice Husk Method, Mini-hatchery PKSF/IFAD In Sand Incubation Technique shown in Figure 1.4 [11], an insulated box like an

almirah (cupboard) is made up of wooden or particle board composed of outlet for gas

emission and ventilation to control temperature. Inside the box there are 3 to 5 gunny sac

trays supported by the wire net which are used as egg setting and hatching trays as well.

At the bottom of the incubator there are two kerosene based hurricane lamps placed as a

source of heat and the bowl with water to maintain the humidity. The lower-most tray

contains sand to be heated and give a distributed uniform temperature (98-100° F or 37-

38°C) within the surrounding area of the incubator.

(a) Diagram of the sand-based incubator and its internal arrangement

(b) Four-shelved incubating box for the sand-type mini hatchery

(c) Front doors of the incubi-tion box are covered with rice-husk filled gunny bags

Figure 1.4: Sand Method, Mini-hatchery PKSF/IFAD


7

A person may easily get a net benefit of around 5,000 to 10,000 taka per month

from a hatchery of 1000 eggs. This technology has been changed socioeconomic status of

many people in the rural areas. Many educated unemployed person are also engaged

themselves in this sector and earning their livelihood, which is encouraging many other

people to engage themselves in this sector.

1.2 Problem Statement

Many people of our country are very much interested in adopting a mini-hatchery

technology, but the main problem is lack of proper technical and financial support. The

PKSF was not very successful in their projects largely on account of poor management of

the supply chain of hatching eggs, poor quality of eggs and the high labor inputs required.

Due to the lack of technology and proper technical knowledge, they could not maintain

proper temperature of the hatchery and the hatching percentage may reduce (below 50%)

or completely stop during the winter period from mid November till February, when

temperatures fall to a low of 20° C [12]. Thus, the hatcheries remain closed for 2-3 months

in winter.

The problems of early hatching, late hatching, pipped eggs with no hatching, blood

rings and dead embryos (the developing chick in an egg is called an embryo) at early stage

of egg embryo development are common problem in these analogues (manual) egg

incubators. These symptoms are a commonly caused by incorrect incubation

measurements. For example, early hatching is caused by high incubation temperature

while late hatching is a result of low temperature. Pipped eggs without hatching that is,

cannot escape from the egg shell are caused by two factors, namely; improper ventilation

and insufficient moisture (low humidity). Blood rings in the eggs are caused by inaccurate

incubation temperature due to manual temperature control; dead embryos at an early stage

are caused by improper egg turnings (needed three times a day) and ventilation [13].

Very few farmers locally manufacture box type egg incubators for their own DOC

production but in those system there are improper control of temperature, humidity, egg

turnings and ventilation. They are not user-friendly and easy to maintain. Commercial and

imported incubators available in the market are far greater in size than requirement of

small villages and highly costly.


8

Incubation and hatching of eggs is an old process, but the act of incubation using

the artificial method is developing day by day. Creating an efficient incubator at a

moderate and affordable price is challenging because egg embryos are delicate even a

slight change of temperature, humidity and ventilation can affect the timing of the

hatchings, likewise a rough turning of the egg can kill the embryo. This situation has

received the attention of researchers, academicians and some non-governmental

organizations to improve the DOC production and to improve the economic condition of

the rural people through poultry rearing.

1.3 Aims and Objectives The aims and objectives of this project are:

i. To design and construct a low cost incubator using microcontroller, IC based

sensors and other materials those are readily available in the local market.

ii. To design an egg incubator that is able to incubate different types of eggs like hen,

duck, quail etc. with minimum external supervision.

iii. To design user friendly Human Machine Interfacing Menu Program (HMIMP) to

adjust and set the different incubation conditions necessary for each type of eggs.

iv. To design an incubator with data logging facility which will help different

Institution’s research laboratories to get a right prediction from output result.

v. To design an incubator to serve a dual purposes i.e. combination of Setter and

Hatcher in a single unit.

1.4 Expected Benefits

In this project, microcontroller based forced air egg incubator is designed,

implemented and tested for multi-stage incubation; the incubator contains different eggs

(Duck, hen and Quail) and of different embryonic ages. The expected benefits of this

project works are:

The construction of the incubator use locally available cheap materials, so its

manufacturing cost is low. It’s all accessories are locally available; maintenance is

easy and low cost. It consumes less power than other egg incubators available in the

market; it can also be operated with alternative source of energy.


9

Present capacities of the incubators are 120 and 400 eggs using same control unit,

same control unit can be use up to 2000 eggs.

Its controller also can help to modernize present mini-hatchery techniques.

By changing the settings any kind of egg (i.e. hen, duck, quail etc.) can be hatched.

It made as user-friendly, portable and easy to maintain, no special skills required to

operate it. It requires minimum external supervision or control that makes it relatively affordable

to the average physically semi-disabled people and poor farmer dwelling in a rural

area.

It is a full function automatic incubator but comparatively very cheap than others

(approximate cost of control unit about Tk. 2000 to 2200 and casing of incubator about

Tk. 1000 to 3000 depending on size and materials used).

A part of the disguised unemployed people can be employed with the family poultry

development and production business by producing their own DOC (Day Old Chick)

in their own egg incubator.

It will play an important role in the day old chick development in the remote village

area in Bangladesh. This egg incubator will save time for farmers, increase their production and hence their

income.

It will help to acquire the goal of “One Home is One Farm” and increase the production of chicks and protein intake in Bangladesh.

Its advance auto saving data log facility in excel is very useful and realistic for getting

right prediction from output result to improve incubator operation for optimum

performance.

It can be used in Agriculture University, Research Institute, College and School for

their (egg embryo) research and laboratory works.


10

1.5 Project Report Layout This report is combination of four chapters that contain the Introduction,

Incubation and Egg embryology, Microcontroller based forced air egg incubator and the

last chapter is a Conclusion and Recommendation of the project.

Chapter 1 introduces the research topic and sets the direction in which the thesis

will proceed. The Background and Justification, Problem statement, Aims and Objectives,

Expected Benefits of the project are explained. The concept of the project and the overall

overview of the project are also discussed in this chapter.

Chapter 2 focuses on the natural and artificial egg incubation process, egg

embryology, important incubation factors required to maintain, to design a successful egg

incubator and various types of egg incubator.

The explanation about Microcontroller Based Forced Air Egg Incubator

(MBFAEI) project is given in Chapter 3.

The project designs, developments and implementations consist of three main parts

which are incubators mechanical structure design, embedded system design (hardware

design and software design) and test hatching for troubleshooting and upgrading the

system.

In mechanical structure design, it is about the development of the case/cabinet of

incubator, egg turning system and ventilation system. This section also, discussed the

construction and assembling procedure in detail with dimension.

In Embedded system design, it is about the development of the software, interface

circuit and hardware design. The design of this system includes two parts. These are the

hardware and software design. For proper functionality of the system, these two parts

adjust to agree with each other.

The hardware unit consists of the following sub-unit: the microcontroller unit, the

sensor unit, the real time clock calendar unit, the user interface and display unit, the auto

saving data logging in MS excel unit, the current driver unit, the actuator unit and the

power supply unit.


11

The control program for the microcontroller was written in Basic language for

code economy and speed reasons. The controller of the egg incubator development to

satisfy the incubation factors during incubation process automatically.

Chapter 4 focuses on test hatching and performance analysis of the designed

incubator. Each stage of the embryonic development and the results obtained during

incubation are also described here.

In Chapter 5, the conclusions and recommendation of the project are presented.

Chapter 2

Egg Incubation and Embryology

2.1 Introduction

Incubation refers to the process by which certain oviparous (egg-laying) animals

hatch their eggs, and to the development of the embryo within the egg. Most female birds

will become broody and sit on and hatch the clutch of eggs (generally 10-12) they have

just laid. The act of sitting on the eggs to incubate them is called brooding. The action or

behavioral tendency to sit on a clutch of eggs is also called broody, and most egg laying

breeds of chicken have had this behavior selectively bred out of them to increase

production. The most vital factor of incubation is the constant temperature required for its

development over a specific period. The more nearly the artificial method of incubation

can copy the natural one, the more successful will be the results. In this project, at first the

conditions of the natural process is observed and these are implemented in the artificial

method.

2.2 Natural Incubation

When a hen becomes broody, the arteries (blood vessel) and veins under the body

become more highly charged with blood and cover the abdomen with a warm network,

which, being pressed against the eggs, keep the latter at a temperature approximating that

of the fowl’s body. During the incubation period she sits on her eggs she frequently turns

Chapter 2. Egg Incubation and Embryology

13

them in the nest for re-arranging them to her own comfort and at the same time fulfill an

absolutely necessary condition for the successful development of the embryo. In settling

down to her eggs, after being off for a time, she generally performs the operation with a

wriggling motion, and in so doing separates the eggs slightly and partly surrounds them

with her downy feathers, a small portion only of each egg coming in contact with her

body. As incubation advances, the small end of each egg has a tendency to turn towards

the middle of the nest, and the broader ends to become slightly elevated and the enlarging

air space in the broad end causing the narrow end to be the heaviest. The number of time a

good sitter leaves her nest, and the length of time she will stay away, depends on the

weather, the degree of fertility in the eggs, and the stage of incubation. In warm weather

this will be of more frequent and of longer duration than in cold weather. She may

sometimes be noticed, when the weather is hot, to rise in the nest and shake out her

feathers as if to cool herself and the eggs. The same remark applies, even in cooler

weather, when the eggs are well fertilized with strong germs at an advanced stage, when

the animal heat in the eggs themselves is great.

In natural incubation heat is applied to the eggs by actual contact with the

incubating body, the body temperature of the sitter diminishes a little as incubation

advances, the fowl loses fat which brings the rich network of blood-vessels in the

abdomen more closely in contact with the eggs. In addition to direct contact, warmth is

applied by the diffusion of heat downwards by the feathers which partially fill the spaces

between the eggs and round the outside of the nest. Cool fresh air comes in under the eggs

and close to the bottom of the nest, gradually ascends to the heat-generating body and

becomes heated, but instead of passing out on the tops of the eggs only its exit laterally is

resisted and retarded by the downy fluff and feathers, which conduct and diffuse the heat

downwards as well as outwards, and hold suspended among them a large volume of warm

moist air, any rapid movement of which being impossible.

Moreover, the outgoing warm air meets and imports most of its heat to the

incoming cool air, so that in the gradual replacement of the volume of air around the eggs

little heat is lost. In addition to this, the earth is a poor conductor, and the heat, instead of

being absorbed, is largely radiated back to the under surfaces of the eggs. Although the

white and yolk of the egg are bad conductors, the shell is an extremely good conductor of

heat, and this property greatly assists in more evenly distributing the warmth to all parts of


14

the egg. The development of the vascular system also adds another important aid to the

conveyance and uniform distribution of heat from the upper to the under surface, and from

the outside to the inside of the egg. Birds are capable of grand engineering feats.

Birds in different part of the world make their nest depending on their body

structure, body temperature, egg incubation factors and environmental conditions where

they live. The nests are the “Engineering without Engineers” as “Structural engineer in

action” to insure the proper incubating environment. The Figure 2.1 shows the different

types of bird nests. As a good structural engineer they use materials more common in their

northern breeding grounds, including moss, grass, lichen and even fur. The ‘nest’ provides

a safe, protected environment for the eggs, with the nest material which enables the

control over the degree of ventilation of eggs. Nests of different species have very

different characteristics, particularly with respect to gas permeability. This in turn affects

water loss from eggs, so it is necessary to adjust the amount of nest material accordingly.

Figure 2.1: Birds Nest Engineering for Proper Incubating Environment

The egg incubation system involves lots of concern and several complex physical

phenomena in terms of the temperature, humidity and movement in order to care the


15

health of the egg. The principles and conditions of natural method, to see wherein, and to

what extent, those principles are applicable to the artificial method, and to endeavour to

show the various influences that may affect, either beneficially or deleteriously, the

embryonic development of the chick in its different stages, are studies during this

MBFAEI project design and implementation. The MBFAEI project designed to enable, to

set all the incubation parameters so that the eggs would experience in their natural nest.

2.3 Artificial Incubation

Artificial incubator is an insulated enclosure in which temperature, humidity, and

other environmental conditions can be regulated at levels optimal for growth and to the

development of the embryo within the egg. The most important difference between natural

and artificial incubation is the fact that the natural parent provides warmth by contact

rather than surrounding the egg with warm air. Artificial incubation was developed with

the main objectives to recreate the temperature and relative humidity close to the natural

conditions. The most vital factor of incubation is the constant temperature required for its

development over a specific period. By allowing mass production of chicks, artificial

incubation has greatly contributed to the rapid expansion of the poultry industry.

Moreover, it has also kept the pace with technical progress. For artificial incubation eggs

of exotic birds and common chickens require a standard measure of care in storage and

incubation to ensure a successful hatch. Environmental conditions, handling, sanitation

and record-keeping can impact the success of incubating and hatching eggs.

Necessity of Artificial Incubation 1. Possible to plan incubate eggs any time.

2. Many eggs can be incubated at a time.

3. Incubation is not affected by the sudden change in the weather condition.

4. Save to spread parasites and diseases to the chicks.

5. The production of rare Aviculture species can be significantly increased.

6. Many pairs lay a second clutch and in some cases triple clutch by removing eggs

and incubating eggs artificially.

7. Save space and cost that are the major factor in obtaining good profit.

8. Chances of eggs spoilage are minimized since all eggs are subjected to the

optimum hatching temperatures.


16

2.4 Egg Embryology

Embryonic development is a continuous process that can roughly be divided into

three different phases. They are differentiation, growth and the maturation. Typically,

differentiation of organs occurs in the early days of incubation. At the start of incubation

the embryo produces little amount heat and then eggs must be warmed. This means that

the air temperature must be higher than Physiological Zero of the egg temperature

(Physiological zero is the temperature below which embryonic growth is arrested and

above which it is initiated). The embryo starts developing when the temperature exceeds

the Physiological Zero. The physiological zero for chicken eggs is about 75oF (24oC). The

optimum temperature for chicken egg in the setter (during the first 18 days) ranges from

99.50oF (37.50oC) to 99.75oF (37.64oC) and in the hatcher (last 3 days) is 98.50oF

(36.94oC). Because, the developing embryo reacts as a poikilotherm, any changes in

incubation temperature may affect embryo size, organ growth, metabolic rate,

physiological development, and hatching success [16-17].

The growth and the maturation of the organs occur in the later phases of

development. Each of these phases requires specific incubator conditions. As the embryo

grows, it’s metabolic rate increases and this is accompanied by increased heat production.

Consequently, the natural pattern of the embryo and eggshell temperature shows an

increase towards the end of incubation. The typical heat production during incubation of

chicken eggs shown in Figure 2.2. The artificial incubator must differentiate between the

temperature set point at which the incubator operates and the temperature of the air at the

level of the eggs, which determines the temperature of the egg and embryo. The

temperature experienced by a developing embryo depends on three factors: incubator

temperature, ability of heat to pass between the incubator and the embryo and metabolic

heat production of the embryo itself [18].


17

Figure 2.2: Heat Production of Incubating Eggs

There are actually two different thermal phases during incubation:

1. The first phase (until 8 days of incubation approximately), when the embryo

requires heat in order to develop, is called the endothermic phase. During this first

phase, insufficient heating, too slow temperature rise or interruption of the “warm

chain” can result in early embryonic deaths and impair the incubation final

outcome.

2. The second phase (from approximately 8 days of incubation onwards) is when the

embryo produces heat, which is needed to be dissipated; hence, this is the

exothermic phase. Besides, some breeds with high growth potential release more

heat than others and it should be taken into account during incubation.

2.5 Important Incubation Factors Required to Maintain for Designing a Successful Egg Incubator

All bird eggs require five environmental conditions to be controlled to enable the

correct development of the embryo:

The egg must be maintained at the right temperature to enable the metabolic processes

within the developing embryo to occur at the correct rate.

The egg must be frequently turned and carefully positioned so that the embryo passes

through fresh nutrients in the white of the egg, while forming in the correct position

for hatching.


18

The egg loses water through pores in the shell. The humidity of the air around it must

be controlled to ensure the right amount of water is lost over the incubation period.

The egg “breathes” so there must be a supply of fresh air to provide oxygen and to

remove waste carbon dioxide.

Eggs are susceptible to infection so the incubator must provide a clean, disinfected

environment.

Many research and studies were carried out by a number of scientists over many years

to identify important incubation factors, those needs to control for creating proper

environmental condition, to enable the correct development of the embryo in an artificial

incubator and to increase its percentage hatchability.

2.5.1 Temperature

The temperature has been indicated to be the most critical and important factor

controlling embryo growth and development [19-20], hatchability [21], and post hatch

performance [22]. Many studies concerning the effects of temperature on hatchability have

been reviewed [23]. The Embryo body temperature has been shown to be governed by

incubation temperature as studies concerning thermogenesis in the chick embryo have

indicated that the embryo cannot properly regulate its body temperature until the hatching

process has been completed [24-27]. Researchers have shown that the major factors

affecting the developing embryo were incubation temperature, thermal conductance of the

egg and surrounding air, and metabolic heat production of the embryo [18]. The rate of

embryonic development is dependent on temperature. Incorrect temperature may alter the

timing of the hatch and may result in incomplete absorption of the yolk. Chicks that

hatched following a severe heat stress were weaker, less alert, and had matted, coarse

down that resulted in an abnormal and unthrifty appearance [28]. Such chicks have been

reported to have a high incidence of clubbed, wiry down, and an unsteady gait [29].

In 1969, H. Lundy’s review five incubation Temperature Zones (shown in Figure

2.3) for chicken eggs in an artificially controlled environment. In common with the most

scientific work on incubation, this data assumes for forced air egg incubator with a fan

(virtually no temperature differences within the incubator) and was based on chicken eggs.

The temperature is measured at the level where the embryos develop (at the top of the egg)

with touch the eggs or incubator.


19

The Five Zones are explained as follows:

Figure 2.3: Five Incubation Temperature Zones for Chicken Eggs

Zone 1: Zone of Heat Injury or Death (Above 40.5°C/ 104.9 °F)

At continuous temperatures above 40.5°C(104.9°F) no embryos would be expected

to hatch. However the effect of short periods of high temperature is not necessarily lethal.

Embryos up to 6 days are particularly susceptible (at risk), older embryos are more

tolerant. For example, embryos up to 5 days may kill by a few hours exposure to 41°C

(105.8°F). When chicken eggs incubated for 16 days are incubated under 40.6℃ for 24

hours, the hatchability will fall down to some degree, under 43.3℃ for 9 hours,

hatchability declining to a great extent, but approaching hatching time they may survive

temperatures as high as 43.5°C (110.3°F) for several hours. When chicken eggs incubated

for 5 days are incubated under 47℃, all the embryos will dies within 2 hours. When the

temperature is over 47℃, the embryo dies within 2 hours. Under 48.9℃ (120ºF) for one

hour, 100% of the embryos in the incubator die.

Zone 2: Zone of Hatching Potential (35.6°C/96.1°F - 40.5°C/104.9°F)

A hen's normal body temperature varies between 40.5°C and 41.7oC, depending on

the bird and her degree of activity at the time. When hatching under a broody hen, the

upper surface of the egg may reach 39.2 to 39.4oC, but the egg's centre will not exceed

37.8°C. Chicken eggs have adaptive capacity awards ambient temperature, and some eggs

can still hatch under temperature range of 35.6°C (96.1°F) to 40.5°C (104.9°F) is called

the zone of Hatching Potential (there is the possibility of hatching eggs). But when an


20

incubation machine is use, the temperature mentioned above is not the most favorable

temperature because the developing embryo can only withstand small fluctuations during

the period. Therefore, it is essential to determine and use a temperature that promotes the

highest hatchability [30],[18] and the best hatchling quality [31], known as optimum

incubation temperature. Setting off optimum incubation temperature leads to the best

hatchability and chick quality [32],[18].

In order to hatch a good percentage of fertile eggs, an incubator must be able to

maintain a constant optimum incubation temperature. Several broad conclusions were

drawn in these reviews: optimum continuous incubation temperature for poultry is

between 37°C to 38°C. Optimum incubation temperature for avian embryos ranges from

37 to 37.5°C [32]. The optimum temperature for chicken egg in the setter (during the first

18 days) ranges from 37.5°C (99.50ºF) to 37.64°C (99.75ºF) and in the Hatcher (last 3

days) is 36.94°C (98.50º F). The best hatch obtained by keeping the temperature at 37.5°C

throughout the incubation period when using a forced-air incubator. Minor fluctuations

(less than 0.5°C) above or below were 37.5°C tolerated, but did not let the temperatures

vary more than a total of 1°C [33], which the implemented Microcontroller Based Forced

Air Egg Incubator (MBFAEI) can accurately provide.

In modern fan-forced incubators, the manufacturer's recommended temperature

setting is between 37.5ºC and 37.64ºC. The lethal temperature for eggs is 39.4ºC. The

constant and rapid air movement in this type of incubator keeps the eggs' temperature the

same as the incubators. Most of the large commercial type incubators and hatchers are run

at 37.22ºC (99ºF). On the other hand, most of the smaller incubators and hatchers, like

those commonly used by game bird producers, are run at 37.78oC (100ºF). Remote

monitoring of egg temperatures during natural incubation has found lower temperatures

than those commonly used for artificial incubation [32],[34].

An embryo's heat production increases as incubation progresses. The temperature

increase is greatest during the last two days due to embryo activity. Egg temperature rises

up to 2ºC above the incubator’s ambient air temperature, for this reason the temperature is

often lowered by up to 1oC during hatching. A decrease in incubation temperature by 2ºC

to 3ºC towards the end of incubation result in an improved embryo growth rate and


21

metabolism while decreasing embryonic mortality and improving chick quality at hatching

[35].

The effect of incubation temperature on egg hatchability and hatching quality may

be related to its influence on incubation length and water loss during incubation. However,

such effects depend on how long and how intense is the shift from optimum temperature.

Temperature fluctuations for short periods of time usually do not severely affect

hatchability or chick quality because the temperature inside the egg changes more slowly

than the air inside the incubator. Developing embryos are fairly tolerant of short-term

temperature drops and the user need not be concerned about cooling that occurs when

inspecting eggs. Therefore opening the incubator regularly to check fertility or for piped

eggs is probably not harmful and will also bring in fresh air. Some recommend that

artificially incubated eggs be cooled once a day to recreate the natural cooling which

occurs when the brooding parent leaves the nest to eat [36].

The embryo development is delayed in temperatures below optimum and

accelerated in temperatures above optimum [20],[29]. Embryo exposed to a lower than

optimal incubation temperature for more than 36 h also had improper positioning of the

embryo and reduced chick weight [37]. Incubation of eggs consistently at below optimal

temperatures resulted in a retard development, delayed hatching time, fewer pipped eggs,

and consequently a lower hatching rate [38]. The chicks may be large, soft bodied, and

weak. However it is again evident that early embryos are more susceptible to continuous

slightly low temperatures than older embryos. It is also reported that at low incubation

temperatures affect the timing of the onset of key physiological processes and their control

that specifically influence growth and maturation of the respiratory system [17].

The increase in temperature during incubation was very critical for embryos [39].

Overheating is much more critical than under heating, under high temperature, the chicken

embryo develops very fast, which may lead to a shortening of incubation period and hence

leads to increase of embryo death rate or decreases the quality of chicks.

The death rate may vary depending on the degree of the temperature overshooting

and the duration of this overheating. Embryos were very sensitive to acute high

temperature during early stages of incubation [40-41]. Moreover, it was reported that


22

growth was retarded or ceased and the incidence of poor second quality chicks increased

as the temperature was raised [29], and lower the percentage of hatchability [13].

Zone 3: Zone of Disproportionate Development (27°C/80.6°F – 35.6°C/96.1°F)

Eggs kept above 27°C (80.6°F) will start to develop, however the development will

be disproportionate in the sense that some parts of the embryo will develop faster than

others and some organs may not develop at all. Below 35°C (95°F) no embryo is likely to

survive to hatch. Typically the heart is much enlarged and the head development more

advanced than the trunk and limbs. Embryos in eggs that spend too much time in this zone

can develop unevenly, leading to crippling injuries or death. Successful hatching is greatly

reduced. When incubated under 35.6℃ (96.1ºF), most of the embryos die in the egg shells.

Little deviation from proper temperature will cause less influence to the embryonic

development, due to adjustment from embryo itself.

The temperature at the lower end of this range is sometimes referred to as

‘Physiological zero’- the threshold temperature for embryonic development. Unfortunately

different organs appear to have different thresholds resulting in an enviable entity.

Zone 4: Zone of Suspended Development (-2°C/28.4°F - 27°C/80.6°F):

Below about 27°C (80.6°F) no embryonic development takes place. Freshly laid

eggs can spend a lot of time at this temperature with no harm to the egg or embryo. Prior

to incubation, eggs must be stored in this temperature range (preferably around

15°C/59°F).

Zone 5: Zone of Cold Injury (Below -2°C/28.4°F):

Below this threshold ice crystals will start to form in the egg and permanent

damage may be done to internal structures. Eggs may lie for some considerable time in

temperatures close to freezing without suffering damage.

The analysis above gives us a fair idea of what may be happening to embryos kept

continuously or for long periods within these temperature bands. Further scientific data


23

has resulted from experiments concerned specifically with intermittent chilling of eggs.

There is evidence that, during the early phase of incubation, chilling of eggs to below

‘physiological zero’ does less harm than chilling to temperatures above that level.

Embryos up to 7 days old may well survive cooling to near freezing for 24 hours or more

without damage. The cooling delays hatching, but not by as much as the period of chilling,

so there appears to be some degree of compensation. The older the embryo, the more

likely it is to die as a result of chilling to below 27°C/80.6°F, but the effect on surviving

embryos is not detrimental.

A number of conclusions from this data which have practical implications that

cooling eggs for short periods, say 30 to 40 minutes, on a regular basis (say once every 24

hours) at any stage during incubation has no detrimental effect and is probably of benefit.

Certainly there is no evidence to suggest that short-term cooling is likely to be harmful. It

may also be best to treat eggs this way up to about the 14th day, although greater losses

must be expected if severe cooling occurs later in incubation. Incubator thermometer

readings will not be the same as embryonic temperatures when cooling or heating occurs.

The eggs will lag behind the air temperature. For example, cooling hens’ eggs by taking

them out of the incubator into a room at 20°C/68°F for 30-40 minutes is likely to cool the

internal egg temperature by only 3°C - 5°C (7°F - 10°F).

There is a very little data on the effects of cooling eggs of other species. Duck eggs

and to an even greater extent, goose eggs, are said to benefit from periodic cooling. The

eggs of both duck and domestic geese have been subjected to severe cooling for prolonged

periods without harm. There is an obvious analogy with the natural process in cooling

eggs periodically. Most species of bird leave the nest for short periods to feed. It is quite

possible that the resulting cooling and re-heating provides a stimulus to the embryo, which

actually encourages growth.

It needs to avoid subjecting the eggs to over-temperature at any time, but

particularly in the early days of incubation.


24

2.5.2 Eggs Position and Turning of Eggs

The eggs position and of turning of eggs are very important during egg incubation.

The proper egg position and turning of the eggs facilitate position of developing embryos

and ensure that nutrients are evenly distributed for embryonic development. Egg Position:

It is natural that the head of the embryo develops toward the large end of the egg

where the air cell is located. In this region each hatching egg should be positioned with the

large end up or horizontally with the large end slightly elevated during incubation. The

proper orientation of the incubating eggs shown in Figure 2.4. This enables the embryo to

remain oriented in a proper position for hatching. When the eggs are incubated with the

small end up, about 60% of the embryos will disorient and develop with the head near the

small end. Thus, when the chick is ready to hatch, its beak cannot break into the air cell to

initiate pulmonary respiration, the chick is likely to drown on pipping and will not hatch.

Figure 2.4: The Proper Orientation of the Egg During Incubation

Eggs positioned horizontally will incubate and hatch normally as long as they are

turned frequently. Under normal circumstances, the eggs are set with large end up for the

first 18 days (in setter) and in horizontal position for the last 3 days (in hatcher). Never set

eggs with the small end upward. When setting in trays, the proper orientation of the egg

during incubation is with the small end pointed down. The air cell should grow at the blunt

end.

Turning of Eggs:

Turning of eggs is very important to fulfill necessary condition for the successful

development of the embryo. The albumen (white) of an egg contains virtually no fat

particles and has a specific gravity near that of water. The yolk has a relatively high fat


25

content. Fats and oils have specific gravities lower than water and float on water. The egg

yolk tries to do the same thing float on the albumen. If an egg is left in one position and

not turned, the yolk tends to float upward through the albumen toward the shell and pushes

the embryo nearer the shell. If the yolk travels rise enough, the developing embryo is

squeezed between the yolk and shell and the embryo will stick to the shell and

development can be fatally distorted or the chick may be malpositioned for proper

hatching or the embryo can be damaged or killed. Turning the egg causes the yolk to be

repositioned away from the shell, making it safe for the developing embryo until time to

turn the egg again and prevents the embryo from sticking to the shell membranes. Turning

of eggs during incubation prevents the developing embryo adhering to the extra-

embryonic membranes and reduces the possibility of embryo mortality and unhealthy

hatches. By this way turning regulates accumulation of protein in amniotic fluid, affecting

embryo growth, hatchability and consequently chick quality. Turning also influences

thyroid hormone levels and corticosteroid production, affecting embryonic response to

stress. It prevents the germ from migrating through the albumen and adhering to the shell.

Moreover, as the embryo develops on the yolk, it causes that part of the yolk to become

lighter and float upwards. The importance of egg turning has been documented in several

studies.

The egg turning is critical for the first week when the embryo has no circulation

system. The turning in the first week of incubation enables proper formation of extra-

embryonic membrane [42]. Egg turning facilitated the transfer of yolk nutrients to the

embryo via the sub-embryonic fluid [43]. Eggs must be turned at least five times within a

24-hour period or better still once every two hours for the first 75% of the incubation

period.

Turning more frequently is better; an automatic turner is recommended. If the

incubator is equipped with an automatic turner, eggs will be turned at least every few

hours. In large commercial incubators the eggs are turned automatically each hour i.e., 24

times a day. Egg turning is particularly crucial during the first 8 days, after the first week,

eggs still need to be turned, but not as often. Take extra precautions when turning eggs

during the first week of incubation. An error in machine programming can lead to 70%

death among embryos. The developing embryos have delicate blood vessels that rupture

easily when severely jarred or shaken, thus killing the embryo. Turning is essential during


26

the first 14 days of incubation and after the first 15 days, egg turning becomes somewhat

more optional. The turning of chicken eggs can be stopped at 16 days (normal incubation

period 21 days) without adversely affecting hatchability [44]. After 18 days, the embryos

are moving into hatching position and turning is not required in hatcher. The incubator

needs to close during hatching to maintain proper temperature and humidity. The air vents

should be almost fully open during the latter stages of hatching.

For small incubators good results can be obtained by turning the eggs the first

thing in the morning, again at noon, and the last thing at night. It is best to turn the eggs

more than three times a day, they should be turned an odd number of times so that the egg

will not be in the same position every night because that is the longest stretch of time

between turns. Eggs in small incubators in the home sometimes get turned only twice a

day, once in the morning and again in the evening. It may be helpful to place an “X” on

one side of each egg and an “O” on the other side, using a pencil. This serves as an aide to

determine whether all eggs are turned. During egg turning, be sure hands are free of all

greasy or dusty substances. Eggs soiled with oils suffer from reduced hatchability.

There is some controversy over the positioning of the egg, on rollers or in a tray.

Rollers are able to turn the eggs completely and the eggs can be set in a more natural

horizontal position. No scientific studies have compared rollers versus trays although

some breeders report better success with rollers.

Figure 2.5: Egg Tray Turning Method

Most commercial incubators are provided with plastic egg trays that hold the egg

vertically, with the small end down. The tray is then tilted through an angle of about 40º

either side of horizontal (an overall angle of 80º). The egg tray turning method is shown in

Figure 2.5. This method works well with poultry for which it was developed, and is very

efficient to operate on a commercial scale. However this is very different from the natural

process adopted by birds.


27

In this project tilting trays turning method with an angle of about 40º either side of

horizontal used.

2.5.3 Humidity

Humidity is one of most critical incubation factors which must be controlled

during egg incubation also it is difficult to measure and control accurately. Incubation

humidity determines the rate of moisture loss from the eggs during incubation. In general,

the humidity is recorded as relative humidity. Relative humidity (RH) is a measure of the

amount of moisture (water vapor) in the air relative to the total amount of moisture the air

can hold. Warmer air can hold more moisture than colder air. Because maximum possible

water content increases at higher temperature, if the temperature was increased, but no

additional water added then, the % RH level would drop.

The relative humidity is expressed as a percentage, so the maximum is 100 %. The

formula for relative humidity is:

One of the most reliable, cheap methods of measuring relative humidity is to

measure wet and dry bulb temperatures and convert the information to %RH by using a

simple chart. Some incubator industry refers to the level of humidity in terms of degrees

F., (wet-bulb) rather than percent relative humidity. The two terms are inter-convertible

and actual humidity depends upon the temperature (F) as measured with a dry-bulb

thermometer. Conversion between the two humidity measurements can be made using a

psychometric table.

Egg shells are porous-the average chicken egg has thousands of pores running

through the shell allowing the embryo to exchange oxygen, carbon dioxide and water.

Soon after an egg is laid, a small air bubble or “air cell” forms in the large end of the egg

of this water loss. During incubation moisture is lost from the egg through the tiny holes in

the shell; this increases the size of the air cell, which after 19 days of incubation occupies

about one-third of the egg [45]. The air cell is crucial for the chick to break out of the egg


28

shell at the end of the incubation period. The chick can drown if the air cell is too small or

the chick may be retarded in growth if the air cell is too large.

The amount of water that an egg loses during incubation is important and this is

determined by the humidity levels within an incubator; if the air is too dry the humidity

level is too low it causes excess evaporation of water, while humidity is too high prevents

the evaporation of sufficient amount of water from the egg. This hatching problem called

red hocks. These chicks could possibly suffer from weak legs [33]. In both cases,

hatchability is reduced [45]. This is why maintaining the proper humidity is crucial. Too

low or too high water loss influences embryo development, and consequently, egg

hatchability [46]. The amount of moisture lost from the eggs during incubation can affect

hatchability [22] and chick weight [47]. Slightly lower humidity levels are more likely to

be less disastrous than slightly higher humidity levels.

Recommended incubation relative humidity for the first 18 days ranging between

55% and 60% (in Setter) and for the last 3 days ranging between 65% and 75% (in

Hatcher). Higher humidity during hatching period is given to avoid dehydration of chicks.

Although a variation of 5 to 10% is acceptable. For higher hatchability the relative

humidity of air within an incubator for the first 18 days should be about 60% during the

last 3days (matching period) should be nearer 70%.

An egg must lose approximately 13-14% of its weight during the incubation

process. For best hatchability, an egg must lose 12% of its weight by 18 days of

incubation. The air cell of the egg should become larger as incubation progresses. Chicken

eggs will lose 12 percent to 14 percent of their total weight by evaporation during

incubation. The mean total weight loss of piped eggs was 12.1% for artificial and 16.0%

for natural incubation [48].

The weight loss rate from lay to pip is linear if the eggs are exposed to the same

temperature and humidity during this period [49] and can be controlled by differing the

level of humidity in the incubator. If the egg is losing weight too quickly, raising the

humidity will slow the rate of evaporation through the egg's pores and conversely

lowering the humidity will increase the rate of weight loss. Convection or a draft created

by the incubator fan has a minimal effect on egg water loss [50].


29

The weight loss rate after piping and up to hatching may be greater than that during

the “setting” period of incubation. The optimum weight loss of eggs during incubation is

shown in Figure 2.6. To determine the entire incubation weight loss the egg should be

weighed moments before hatching which is difficult to time correctly. As the embryo was

turning in the egg and determined that peregrine eggs lost 2.2% of the fresh egg weight

between piping and hatching in a forced air hatcher set at 37.0°C and 60% humidity. This

weight loss could be used as an approximate estimate for other altricial (pattern of growth

and development in organisms which are incapable of moving around on their own soon

after hatching or being born) species to add to lay to pipe data to determine the total

fractional weight loss over the entire incubation period.

Figure 2.6: Optimum Weight Loss of Eggs during Incubation

Incubator humidity has correlation with incubator temperature, ventilation forced

air fan speed and also with incubator room humidity. The temperature can highly

influence the relative humidity, and both contribute to water loss during incubation, this

way temperature and humidity must be carefully monitored during incubation, because the

embryo is not able to control the water loss of egg. For optimum hatchability during

incubation, eggs need to lose 11-14% of their weight in the form of water vapors.

Incubation temperatures above the optimum cause excessive egg water loss (higher than

14%), leading to embryo mortality by dehydration. On the other hand, temperatures below

the optimum decrease hatchability due to reduced water loss (< 12%), which causes an

over-hydration of the embryo and an impairment of gas exchange [31].

If by restricting ventilation the humidity is made too high (92 ºF to 94ºF) during

the final stages of incubation, the embryos are moist and develop to the 19th, 20th, or 21st


30

day of incubation, but die in the shell from suffocation. This suffocation results from

improper ventilation rather than high humidity.

Effect of Higher Humidity:

In natural incubation the membranes cannot dry quickly because the parent bird is

sitting on the egg but in an incubator drying membranes can be a problem, but for artificial

incubation higher humidity levels are required to prevent the membranes of egg drying too

fast as the chick hatches and becoming tough and difficult to tear. The actual level of

humidity is not too critical for hatching but needs to be at least 60% RH.

If the humidity in the incubator is too high during incubation, too little water will

evaporate from the egg, in that case the air space will be too small, the chick’s respiration

will be affected and the young bird will have difficulty breaking out of the shell because of

the lack of space. The chick will either drown or the chick will be too swollen with water

to turn itself within the egg. The yolk sac will also be too large for the navel to completely

close. These problems will cause the hatch to fail.

If several large, soft bodied, mushy chicks are observed that make it through

pipping and hatching but are dead in the tray, it is a sign of high humidity. A bad odor

usually accompanies this condition. The condition normally occurs only in incubators and

hatchers that have forced spray humidity systems that force too much moisture into the

machines. Rarely does humidity run too high on a machine that relies on evaporation from

pans if you are using the recommended evaporative pans, if the temperature is correct, and

if the machines are properly and amply ventilated with fresh air.

Effect of Lower Humidity:

Low incubation humidity levels lead to small chicks with large air spaces by the

time the hatch is due. These chicks will tend to be weak and may also die just before,

during or just after hatching. It should be noted that in general that a slightly lower

humidity level than optimum is likely to be less disastrous than a slightly higher than ideal

level.


31

Excessive moisture loss from the eggs during storage before setting can produce

the same symptoms that low humidity in the machines produces. A sign of low humidity is

sticky embryos during piping and hatching that results in embryos not being able to turn

themselves in the shell and complete the act of piping and detaching themselves from the

shell. Low humidity also results in short down on the chicks, malformed, malpositioned,

weak, and small chicks. Low humidity contributes to (but is not wholly responsible for)

spraddlers, star gazers, and those that cannot stand, walk, or orient themselves well enough

to reach food and water.

When humidity is too low during incubation, too little moisture results in excessive

evaporation, the air cell did too large at the time of hatch causing chicks to stick to the

shell sometimes and hatch crippled at hatching time. The contents of the egg will be too

thick and sticky for the chick to turn. The membranes will be too tough to break. The

navel will not close properly.

An egg loses 11-13 per cent of its inherent moisture during incubation. If humidity

is too low, the moisture loss is excessive, hatching is delayed and many embryos fail to

hatch even if they go to full term. If humidity is too high, the chicks tend to be forced out

early and are wet.

The relative humidity of the air within an incubator for the first 18 days should be

able 60 percent. During the last 3 days (the hatching period) the relative humidity should

be nearer 65-70 percent.

Controlling Humidity:

Humidity needs to carefully control to prevent unnecessary loss of egg moisture.

Setters will need to be adjusted to ensure that the weight loss of the egg is 12% by 18 days

of incubation. The relative humidity in the incubator between setting and 3 days prior to

hatching should remain at 58%-60% or 84-86º F wet-bulb during incubation is

satisfactory. On day 19, the humidity needs to raise about 65% -70% for hatching. By this

stage the weight loss of the egg should be 13-15% and water loss for the last 24-48 hours

will not significantly affect this. Then, towards the end of the day 21 when all chicks that

are likely to hatch have hatched, reduce humidity to 60 per cent. This enables chicks to dry

off before being taken out.


Achieving Correct Humidity Levels Humidity can control by the size of the intake

shutting ventilation holes, However proper ventilation is needed to provide O2 and remove

CO2 from the incubator and restriction of this flo

recommended.

Incubators and hatchers have pans filled with water to create humid conditions and

to provide humidity inside the incubator. The water's surface area rather than depth

influence humidity. The total sur

adjusted until the correct humidity is achieved.

Humidity can be control

over the water tray. During the hatching period, using an atomizer to

of water into the ventilating holes may increase the humidity in the incubator. This is

especially helpful when duck o

Achieving Correct Humidity Levels by

Figure 2.7

It is also possible to determine whether there is too much or too little humidity in

the incubator by candling the eggs and observing the size of the air cells and marking air

cells and also by weighing. The growth of this air cell is a balance between tem

and humidity during the incubation.

shown in Figure 2.7. Racks of eggs can be weighed during incubation to detect problems

with humidity and evapora

Egg Incubation and Embryology

32

Correct Humidity Levels by Changing Water's Surface:

Humidity can control by the size of the intake-exhaust air vents and by opening or


CO2 from the incubator and restriction of this flow to increase incubator humidity is not



influence humidity. The total surface area of water determines the humidity and should be

adjusted until the correct humidity is achieved.

controlled by using the water tray’s position or moving slides

over the water tray. During the hatching period, using an atomizer to spray a small amount


especially helpful when duck or goose eggs are being hatched.

Correct Humidity Levels by the Size of the Air Cells:

7: The Growth of Air Cell during the Incubation



cells and also by weighing. The growth of this air cell is a balance between tem

and humidity during the incubation. The proper growth of air cell during the incubation

Racks of eggs can be weighed during incubation to detect problems

with humidity and evaporate loss before a hatch is destroyed.

exhaust air vents and by opening or


w to increase incubator humidity is not



face area of water determines the humidity and should be

s position or moving slides

spray a small amount


the Incubation



cells and also by weighing. The growth of this air cell is a balance between temperature

growth of air cell during the incubation is

Racks of eggs can be weighed during incubation to detect problems


33

Achieving Correct Humidity Levels by Weighing the Eggs:

There is a fairly easy and reliable way of measuring RH indirectly and directly

measuring the effect that RH level has on the egg by weighing the eggs to monitor their

water loss over the incubation period. Most species of birds need to lose between 13 and

15% of their weight from the time of setting the eggs in an incubator for hatching. By

measuring the weights of the eggs at intervals during incubation, taking the average

weights and comparing these to the expected weights needed to achieve the ideal weight

loss by hatching, it is possible to see when the rate of water loss is too great due to

humidity being too low and vice versa. In practice this means drawing a graph (as shown

in Figure 2.8) with incubation time in days along the x-axis and weight up the y-axis. The

average weight of eggs when set (day 0) can be entered and the ideal hatching weight

(average day 0 weight less 14%) can be plotted on the day the hatch is due. These two

points are then joined to give the ideal weight loss line. Average weights can then be taken

every three or four days and plotted on the graph. If the actual average weights are lower

than the ideal, then humidity levels need to be increased and vice versa. Thus any

deviation from the ideal weight loss line can be corrected as incubation progresses. The

important point is to reach the ideal weight loss by hatching day; some deviation from the

ideal weight loss line earlier in incubation will have little adverse effect.

Figure 2.8: The Average Actual Weights of Incubating Eggs against the Ideal Weight Loss Line

The graph above shows the average actual weights of incubating eggs against the

ideal weight loss line. The greater than the ideal weight loss in the earlier stages of

incubation has been corrected by hatching day.


34

The Importance of Keeping the Incubator Closed During the Hatching Period:

To increase humidity within an incubator it is very important to keep the incubator

closed for in the last 3 days of incubation. Humidity levels drop rapidly when the

incubator is opened and took much longer than temperature levels to re-establish. It is very

tempting to keep opening and checking or wanting to help a baby chick out of the shell.

Normally the chick does just fine on its own. The hatching may take several hours. Do not

rush the chick. Many chicks have died in the shell without having the opportunity to hatch

because someone just could not leave the incubator closed during this critical time.

2.5.4 Ventilation and Oxygen Availability

Ventilation is very important during the incubation process. Egg shells contain

three to six thousand small holes, called “pores”, oxygen enters the egg through the shell

and carbon dioxide escapes in the same manner. The embryo's lungs are not developed

during early embryonic development to the point that they can accommodate respiration

by breathing. Respiration, therefore, is provided during the first three to five days by the

vitelline blood circulation plexus growing from the embryo. To reach this plexus the

gaseous exchange must travel through the egg pores and the albumen (egg white) to reach

the vitelline circulation, which lies on the surface of the egg yolk. After the 4th or 5th day

of development another structure, called the “allantois” grows from the embryo, extends

through the albumen, and positions itself just underneath the egg shell. The allantois

becomes the primary respiratory organ of the developing embryo and remains such until

just before piping begins. The transfer of respiratory function from the allantois to the

lungs begins three or four days before pipping. The transfer is gradual and is completed by

the time the chick finishes pipping the egg shell. The important thing to remember about

embryonic respiration is that ventilation is important throughout the incubation process,

especially toward the end, because the embryos are larger and respiring at a much higher

rate than in the beginning. The egg breathes, taking in oxygen (7 grams in 21 days) and

giving off carbon dioxide (9 grams).

Ventilation must be minimal at the beginning of hatching in order to help initiate

pulmonary respiration (which is prompted by a high-level of carbon dioxide), and later

must be increased until becoming maximal at the end of hatching. If ventilation is poor the


35

first thing noticed may be a poor hatch. Lack of proper ventilation can contribute to low

hatchability if, after examining numerous dead embryos in the shell, the majority of

embryos reaches the 19th or 20th day of incubation. Ventilation is a major factor at the end

of the cycle.

The fresh air drawn from the incubation room therefore provides the eggs with the

oxygen and humidity that they need, and takes away the carbon dioxide and excessive heat

that they produce. As embryos grow, the air vent openings are gradually opened to satisfy

increased embryonic oxygen demand. The supply of fresh air must be sufficient to prevent

a lack of oxygen and choking. Care must be taken to maintain humidity during the

hatching period. Unobstructed ventilation holes, both above and below the eggs, are

essential for proper air exchange.

The best hatching results are obtained with normal atmospheric air, which usually

contains 21 percent oxygen and approximately 0.4% for carbon dioxide (0.2% during the

first phase and 0.5% at the time of transfer). For every 1% drop in oxygen there is 5%

reduction in hatchability. The tolerance level of CO2 for the first 4 days in the setter is

0.3%. CO2 levels above 0.5% in the setter reduce hatchability and completely lethal at

5.0%. Since the normal oxygen and carbon dioxide concentration presents in the air seem

to represent an optimum gaseous environment for incubating egg, no special provision to

control these gases is necessary other than to maintain adequate circulation of fresh-air at

the proper temperature and humidity. It is difficult to provide too much oxygen, but a

deficiency is possible. Make sure that the ventilation holes are open to allow a normal

exchange of air. The air supply to the setter room should be 8cfm (13.52 cubic meters hr)

per 1000 eggs.

2.5.5 Sanitation

Good sanitation must be maintained to prevent disease in the hatchery. The

conditions provided to maintain embryonic growth in the incubators are also ideal for the

growth of bacteria and molds. Good design is essential for cost-effective incubator

operation. Incubators should have the durable wall; wall surfaces should have a minimum

of joints and fastenings that impede effective cleaning.


36

It is imperative that people wash and sanitize their hands before collecting eggs

from the nests or egg belts. The flats that eggs are placed on must also be sanitized and

free of organic material. Birds need to provide clean and nest place for egg laying and

collect hatching eggs three times a day. Eggs laid in dirty place can be covered by

contaminating microorganisms from the feces or feather material of the parents or

previous nestlings. Dirty, cracked, or porous eggs will not set for incubation. The washing

and rubbing action also serves to force disease organisms through the pores of the

shell. Omphalitis, yolk sack infection is caused by a bacterium that enters through the

porous egg shell and easily kills embryo's and newly hatched chicks. Unfortunately,

incubation conditions are ideal for breeding bacteria as well as incubating eggs. Eggs that

are of good size, not abnormally big or small, clean should be select for hatching. Soiled

eggs should be carefully dry cleaned by gently buffing the soiled area with fine sandpaper

or steel wool.

Eggs should not be washed. Washing or wiping with a damp cloth removes a

protective layer that coats the egg. Washing eggs transfers disease infection agents from

the surface to the inside of the eggs. Contraction of egg contents draws water into the egg

through pores in the shell. This water carries infecting microorganisms into the egg. If an

egg is washed, it should be washed briefly in 110-degree F water that contains a

commercial egg sanitizer. Washing an egg in water that is cooler than the egg itself causes

egg contents to contract.

It is essential to use a disinfectant, which is formulated to be used for cleaning

eggs, incubators, safe and effective against yeasts, fungi, viruses and bacteria which can

cause fatal damage to the growing embryo. Fumigation of eggs has been a common

method to kill shell surface micro-organisms. Fumigation should only be done with fresh

eggs, older eggs can be killed. Incubators made out of porous wood or polystyrene and

others with hard to reach areas can only be effectively disinfected by fumigation. Eggs to

be hatched should always be put into a place with proper sanitation.

The pans of water used in incubators for humidity control, provide growing media

for pathogenic bacteria, especially in the warm environment of an incubator, and should be

disinfected periodically. Use distilled water or the use of boiled water that has been


37

cooled, in incubator trays will reduce the chance of unwanted organisms being introduced

from the tap water. Whenever adding water to an incubator, it should be about the same

temperature as the incubator, a good test is to add water just warm to the touch.

Omphalitis, Mushy Chick Disease and Yolk Sack Infection may be caused by a bacterium

that enters through the porous egg shell.

Broken, infertile and spoiled eggs need to remove as soon as possible. When

chicks and ducklings start to hatch, egg shells and weak or dead chicks remove

immediately. After all the eggs have hatched, remove the trays and cloth liners and wash

and disinfect them thoroughly.

Sources of contamination other than infected eggs and chick fluff are airs, people

(both workers and visitors), animals such as rats and mice, wild birds and insects, and

equipment such as boxes, trays and buggies.

It needs to ensure that all workers and visitors wear suitable protective clothing. It

is good practice to use different colored uniforms according to location (clean or dirty part

of the hatchery) or task. This helps to identify incorrect movement of workers and hence

possible cross contamination.

2.6 Length of Incubation

Chicken eggs require 21 days to hatch, but the incubation period for the eggs of

other species of poultry varies. The incubator period and incubator operation for eggs of

domestic birds are shown in Table 2.1:


38

Table 2.1: The Incubation Period and Incubator Operation for Common Domestic Birds (Part-1)

Chicken Duck Coturnix Quail Pigeon

Egg Storage before Incubation

Egg Storage before Incubation <8 days <7 days <7 days <7 days Temperature 13ºC -18ºC 13ºC -18ºC 13ºC -18ºC 13ºC -18ºC Best Temperature 55ºF(13ºC) 55ºF(13ºC) 55ºF(13ºC) 55ºF(13ºC) Humidity 70‐85% RH 70‐85% RH 70‐85% RH 70‐85% RH Best Humidity 75% RH 75% RH 75% RH 75% RH

Incubation Period (Days)

Incubation Period (days) 21 28 17 17 Successful Incubation (days) 20-22 27-29 17-18 17-18

Setter Operation

Temperature 37.5ºC-37.64ºC 37.5ºC-37.64ºC 37.5ºC-37.64ºC 37.2ºC-37.5ºC Best Temperature 37.5ºC

(99.5ºF) 37.28ºC (99.1ºF)

37.64ºC (99.75ºF)

37.64ºC (99.75ºF)

Humidity (% rH) 55%-60% 55%-60% 45%-55% 45%-55% Best Humidity (% rH) 55% 55% 55% 55% Egg turning per day (Manual) 8 times 8 times 8 times Egg turning per day (Automatic) 24 times 24 times 24 times

Hatcher Operation

Do Not Turn Eggs After 19 th day 25th day 15th day 15th day Temperature 36.94ºC-37.22ºC 36.89ºC-37.01ºC 37.22ºC 37.22ºC Best Temperature 36.94ºC

(98.5ºF) 36.89ºC (98.4ºF)

37.22ºC (99ºF)

37.22ºC (99ºF)

Humidity (% rH) 65%-70% 65%-70% 55%-65% 55%-65% Best Humidity (% rH) 65% 65% 60% 60% Increase Ventilation 10 th and

18 th day 12th day and

25th day


39

Table 2.2: The Incubation Period and Incubator Operation for Common Domestic Birds (Part-2)

Geese Muscovy Duck

Guinea Bobwhite Quail

Egg Storage

Egg Storage before Incubation <7 days <8 days <14 days Temperature 55‐65º F 55‐ 65º F 55‐65º F 55‐65º F Humidity 70‐85% RH 70‐85% RH 70‐85% RH

Incubation Period (Days) Incubation Period (days) 28-34 35-37 28 23-24 Successful Incubation (days) 28-34 35-37 26-28 22-24

Setter Operation

Temperature 99.25 ºF 99.50 ºF 99.75 ºF 99.75 ºF Best Temperature 99.0ºF 99.5ºF 100ºF Best Humidity (% rH) 45%-55% 45%-55% 45%-55% 45%-55%

Hatcher Operation

Do Not Turn Eggs After 25th day 31st day 25th day 21st day Temperature 98.50ºF 98.75ºF 99ºF 99ºF Best Temperature 99.0ºF 98.0ºF 99.0ºF Best Humidity (% rH) 55%-65% 55%-65% 55%-65% 55%-65%

Factors Affecting the Incubation Period

The total incubation time of eggs normally fixed for any hatchery, but to achieve a

desired pull time for chicks, variation in the time at which eggs are set can be modified

according to incubation temperature, age and size of eggs.

The Incubation Temperature: the higher the incubation temperature, the shorter

the incubation time. A temperature too high leads to early hatching and smaller chicks;


40

whereas a temperature too low results in hatching delay from 2 to 12 hours depending on

temperature, and larger chicks. In both cases, extremes also lead to an increase in

embryonic mortality.

The Age of the Eggs: stored eggs take longer to incubate, beyond 5/6 days of

storage, each additional day prolongs the incubation time by one hour.

The Size of the Eggs: larger eggs take longer to incubate, beyond 50 grams, each

2.5gram range prolongs the incubation time by half an hour.

Numerous secondary factors also influence incubation time: breed (layer type or

meat type chickens), period of the year, the number and type of eggs in the incubator, type

of incubator used.

2.7 Monitoring of Eggs and the Incubator

Eggs need to be monitored during incubation to determine embryo progress and

where incubation adjustment may be necessary.

Candling is the process of shining light with a concentrated beam that may be

shone through the shell of the egg to illuminate the egg contents to determine whether the

egg is fertile, infertile or spoiled. It allows the size of the airspace to be determined which

offers a guide to the weight loss rate.

If the air space is larger than expected too much water is being lost and the

humidity in the incubator should be increased to reduce the rate of water loss. If the air

space is smaller than expected, then the opposite applies.

The candling recommends on Day 7 and Day 14 for chicken eggs, and Day 7 and

21 for duck eggs. The principle is simple: In a dark room a source of light is placed against

the eggshell, and the light passes through illuminating its contents. If the egg is fertile a

tiny network of blood vessels emerging from a dark red spot (similar to a spider) will be

seen (see photo below). If the egg is infertile the yolk will appear as a floating shadow

with no sign of blood vessels and if the egg is spoiled it will appear opaque.


41

Figure 2.9: Candler (a) Candler using Light Bulb, (b) Candler using Torch

A Candler can be easily made by using a 25 to 60 Watt light bulb (if electricity is

available) or a candle placed in a container (small box or empty tin can), with a hole (3-4

cm) to let the light pass through as shown in Figure 2.9(a). A battery torch can also be

used with a box or tin can placed on top and the egg positioned over a hole to allow the

light to shine through as shown in Figure 2(b). Candling is performed before transferring

the eggs on hatching trays. It is reasonable to fill the trays to 90% of their capacity.

2.8 Different Types of Egg Incubators

Incubators come in a variety of types and sizes to fulfill different needs, from a

classroom setting to a full-blown commercial operation. The basic incubator is a box with

a heating element and some sort of ventilation. Fancier models also include automatic

turners and fans for evening of temperature and humidity. Some include places for the

chicks to brood for a period after hatching. Some have small windows, some are

completely visible for great viewing.

Some incubators are flexible and can house different types of poultry eggs simply

by changing a divider or adding a different egg tray. Some need to be constantly

monitored to ensure the correct temperature is maintained, some are automatic or

computer controlled. There is a model available for each situation and every budget.

Educational Incubators

These incubators usually come in complete kits for a total hatching experience for

the schoolroom, home school, 4-H or other educational group. The incubator is small with

maybe a capacity of 3 chick eggs and usually has a large window for easy viewing. These

often have all the bells and whistles for ease and success of hatching and a price tag to

(a) (b)


42

match. It is possible to purchase just the small incubator for about $20 or the whole kit and

caboodle, including small brooder for $300-$400.

Small Hobby Farm Incubators

There are a variety of incubators available for the hobby farmer with a backyard

flock. A basic Styrofoam model can hold 30-40 chicken eggs, with no fan or automatic

turner for the cheapest alternative. Add the fan and turner for a more consistent

temperature and increased hatchability. There are also fancier models with more reliable

controls and long-term reliability. Extra attachments are available for some models that

allow a variety of eggs to be used (chicken or quail or duck etc.) The prices in this

category range from $50 to over $600.

Large Capacity Incubators

For the more serious enthusiast or commercial enterprise there are large capacity

incubators. Hundreds of eggs can be hatched at once, some with staggered hatching dates

so that a new batch is ready every week. These units are computer run for precise

management of all the parameters and fantastic hatch rate. These incubators start at $750

and go up from there, depending on size and features.

2.9 Size of Incubator

The size and type of incubator selected depends on the needs and future plans of

each producer. Many different models are available. For continuous settings, separate

incubator and hatcher units are recommended. If all eggs in the unit are at the same stage

of incubation, a single unit can be used.

Locate the incubator and Hatcher units indoors to protect them from major weather

changes. It is essential that the room has a good ventilation system to supply plenty of

fresh air. Keeping the units indoors makes it easier to maintain uniform temperature and

humidity. The size and type of incubator selected depends on the needs and future plans of

each producer. Many different models are available. For continuous settings, separate

incubator and hatcher units are recommended. If all eggs in the unit are at the same stage

of incubation, a single unit can be used.


43

Locate the incubator and hatcher units indoors to protect them from major weather

changes. It is essential that the room has a good ventilation system to supply plenty of

fresh air. Keeping the units indoors makes it easier to maintain uniform temperature and

humidity.

2.10 Incubator Construction and Function

Incubators are machines, which artificially provide the egg with the correct,

controlled environment for the developing chick. Depending on complexity, an incubator

will give varying degrees of control over temperature, humidity, egg turning, fresh air

flow and hygiene, while providing a secure place for the eggs.

There are two types of incubators depending on construction, function and the

process of surrounding the egg with warm air. These are the much smaller still-air type

used for incubating small numbers of eggs and the larger forced-air type found in

commercial hatcheries.

2.10.1 Still Air Incubators

Still air incubators are the most basic form of incubator. The typical still-air egg

incubator shown in Figure 2.10. The air inside a still air incubator circulates by

convection. As the air is heated it expands and rises to the top of the incubator. The

amount of air flow achieved in a still air machine is therefore determined by the ratio of air

temperature inside the box to outside.

Figure 2.10: Still-air Egg Incubator

The lower the air temperature outside the box the greater the airflow inside. To


44

achieve good air circulation, air inlets are usually positioned in the base and top of the

incubator. Inside a still air incubator, the warm air moves towards the top so different

temperatures will be recorded at different levels. It is therefore important that a still air

incubator is kept on a level surface and that the eggs are all of similar size.

2.10.2 Forced-Air Draft Incubators

Forced-air draft incubators are developed to overcome temperature gradient

problems throughout the incubator. In a forced draft incubator a fan is used to circulate the

air, which gives a uniform temperature throughout the machine. The typical forced draft

egg incubator shown in Figure 2.11.

Figure 2.11: Forced-air Draft Incubator

It is of more importance to control humidity in a forced air machine to prevent the

higher airflow drying the eggs. The air temperature surrounding the egg is constant due air

circulating fan and positioning of the thermometer and temperature sensor is less critical.

Eggs, too, can be of differing size and set in trays at different levels.

Both still-air and forced-draft incubators are used in hatcheries. Still-air incubators

have no such fan which usually results in a temperature gradient increasing to the top of

the incubator and closer to the heating element. Still-air models need to be operated at

slightly warmer temperatures so that the optimum average temperature of the eggs is

achieved. Each model may have different gradient or zone characteristics and this

variability makes still-air incubators difficult to monitor and control at the required steady

temperature. However, all the new incubators are forced-draft. Forced-air incubators have

a continuously running circulation fan keeping the conditions within uniform. They are

capable of maintaining more even temperature, humidity, and oxygen levels than still air


45

incubators. Most of today’s large incubators are the forced-air type. They have fans that

circulate the air in the incubator and around the eggs.

The Table 2.3 shows the advantages and disadvantages of still air incubator and

forced draft incubator.

Table 2.3: The advantages and disadvantages the still-air and the forced-air incubator

Option Advantages Disadvantages

Still Air

Incubator Simple

Cheap

All eggs should be similar sizes

Only one level of hatching is

available

Temperature distribution isn’t

uniform

Forced air

incubator

Different egg sizes can be

hatched at different levels

Gives a uniform

temperature distribution

Allows the use different

types of sensor

Reliable

More complex

More cost

This project option involves the use of discrete components in easy, efficient and

cost effective egg incubator. Considering the advantage and disadvantage of these two

types of egg incubator Forced-draft incubator is preferred. That is why this project works

based on the forced-air draft incubation method.

Chapter 3 Design of a Microcontroller Based Forced Air Egg Incubator 3.1 Introduction In this project microcontroller based low cost incubator design, construct and

implement using locally available material and resource, to achieve a cost effective design.

It is able to incubate different types of eggs and it is a full function automatic forced air

egg incubator. The incubator automatically controls temperature, humidity, ventilation.

Also automatically eggs turning usually by slowly rocking them backwards and forwards

continuously. The incubator consists of three main parts. The first part is the incubator

casing. The casing has good physical properties to ensure good thermal isolation between

the interior room of the incubator and the external environment. The capacity of this

incubator is to incubate 120 eggs at a time. The second part is the automatic eggs tray

turning system. The last part is the microcontroller based controller used to measure and

control temperature, humidity, ventilation and eggs turning. The heart of the control unit is

the PIC16F877A which can determine the critical heat required and transfer function in

the incubator and regulate automatically.

3.2 Incubator Design Considerations and Implementation

Good design is essential for cost-effective incubation operation and design must

therefore incorporate food hygiene standards. The conditions provided to maintain

embryonic growth in the incubators are also ideal for the growth of bacteria and molds.

Chapter 3. Design of a Microcontroller Based Forced Air Egg Incubator

47

The outer surfaces of eggs must be free from contamination and all room surfaces, items

of equipment and incubators must be designed to allow simple, regular and effective

cleaning and sterilization. The incubator should be made with readily available materials,

relatively cheap and be within the buying capacity of local farmers, able to hatch different

shapes and sizes of egg, have higher capacity compared to natural methods, be simple to

operate and maintain by local farmers who do not have any formal education.

The project implementation flow chart is shown in Figure 3.1.

Figure 3.1: Microcontroller Based Forced Air Egg Incubator Implementation Flow Chart


48

Design and implementation of a Microcontroller Based Forced Air Egg Incubator

(MBFAEI) project development divided into three main design parts. There are: part 1 is

Mechanical structure design, part 2 is Embedded system design, this part is divided in to

two (a) Hardware design and (b) Software design. Then part 1 and part 2 are combined

together to perform the overall system operation and to provide proper embryonic

development environment and last part is test hatching to troubleshooting and upgrading

the system.

The microcontroller based forced air egg incubator have the following features; the

incubator has heating device, egg turning device, ventilation device and humidity device.

It has total four-heating bulbs with individual control and control parameter setup. This

forced air draft incubator has two circulating fans circulate the hot air and gives a uniform

temperature throughout the incubator. This helps to overcome the temperature gradients

throughout the incubator. Automatic ventilation system provides oxygen properly to

increase successful hatchability.

3.3 Mechanical Structure Design of the Incubator

The egg incubators mechanical structure design consist the development of

incubators enclosure where the eggs are sets to incubate successfully.

3.3.1 Incubator Casing

The first step for making the incubator was to build the incubator enclosure or

casing. The enclosure has good thermal isolation properties to keep the eggs warm and the

temperature constant in all parts of the incubator. A unique combined incubator was

designed that combines both the setting and hatching phase incorporate in a single unit to

save money and space by combining the two processes in a single unit.

The size of the incubator cabinet is taken depending on the number of 120 eggs to

be incubated and with necessary space to inspect the eggs. Incubator casing has the

following features: Durable wall and floor finishes and easy-to-clean. Wall surfaces have a

minimum joints and fastenings that impede effective cleaning. Microcontroller based

forced air egg incubator prototype is shown in Figure 3.2.


49

Figure 3.2: Microcontroller Based Forced Air Egg Incubator Prototype

A good quality material was used such as locally available hard plywood for

making casing of incubator. Wood is a good choice as long as it can be kept clean and free

of moisture. The softer wood will warp during the incubation process. The dimensions of

the incubator are given in table 3.1.

Table 3.1: Internal and External Dimensions of the Incubator

Dimensions Length (mm) Width (mm) Height (mm)

External 490 470 1280 Internal 440 420 1220

Thickness 50 50 60


50

Typical view of the incubator casing during construction process shown in Figure 3.3.

Figure 3.3: Typical View of the Incubator Casing during Construction Process

The performance of the incubator is directly related to the quality of its insulation.

Insulation is very important to keep the temperature constant. The incubator consists of a

wooden cabinet lined with multilayer insulating material as main ingredient (element) to

insulate against heat loss and system is properly lagged, thus leading to very small loss of

energy.

From inside to outside multilayer insulating layer are: First insulating layer is

formed by two coats of varnish allowing each coat to dry. The varnish prevents the hidden

ends are sealed against humidity and infiltration of disease organism and warping in the

high humidity of the incubator and allows washing the trays with disinfectant. Second

insulating layer is case is made of 19 mm plywood. Third insulating layer is made of 12

mm Polystyrene insulation sheet. The Figure 3.4 shows insulation layer in between

plywood. Forth insulating layer is again case is made of 19 mm plywood and fifth

insulating layer is again formed by two coats of varnish allowing each coat to dry. The

varnish prevents the hidden ends are sealed against outside weather. Bottom layer is

covered with Formica sheet.


51

Figure 3.4: Insulation Layer in Between Plywood

By provide a constant temperature, proper insulation also saves fuel. Low power

consumption and good temperature control depends on preventing unwanted air leakage

from the unit. All fixed parts are connected together with good quality wood glue.

Insulation material that holds a lot of air is best. Polystyrene or cardboard can use

to line the inside of a single-wall incubator, or for a double-walled system can stuff hay,

coconut fiber or cotton between the two walls. As air is trapped in such material, there is

almost no movement of heat from the inside to the outside of the walls. Besides it should

help to keep the temperature near the walls the same as in the middle of the incubator.

The door has an insulated glass window in it (shown in Figure 3.5), so that the

temperature, humidity and others can be checked without having to open it.

Figure 3.5: Typical View of Door with Glass Window


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3.3.2 Heating Element and Heating Cable

For construction of automatic eggs Incubator Incandescent lamps are suitable

heating elements due to their carbon free heating capability. Four Incandescent lamps

Heater used as heating element named as Top Heater-1, Top Heater-2, Bottom Heater-1

and Bottom Heater-2 with individual control and control parameter setup. Top Heater-1

and Bottom Heater-1 is 40Watt, 230V, Top Heater-2 and Bottom Heater-2 is 60Watt,

230V. Total 200 Watt.

3.3.3 Egg Setter Tray

Egg setter tray is a section in the incubator wherein eggs were set for most of the

incubation. It is connected to a lever that provides the turning of the eggs. Locally

available low cost plastic egg tray holds 30 eggs (shown in Figure 3.6). Egg setter tray

dimension shown in Table 3.2. For a system capacity of (4×30) 120 eggs four egg trays

are set in vertically.

Table 3.2: Egg Setter Tray Dimension

Dimensions Length (mm) Width (mm) External 255 255

Figure 3.6: Egg Tray

3.3.4 Tray Supports

The egg-trays sit on tray supports which are fixed in the incubator so the trays can

be removed. The tray support frames are composed of a 25mm PVC angle (Figure 3.7).

This type of PVC angles are locally available and low cost and it can easy to cut by hand

saw and can easily band to give required rectangular shape by a soldering iron generate

heat. Then final end points are joining by 20mm screw (nut and volt). The overall

dimensions are 275 × 275 mm.


53

Figure 3.7: Tray Supports

There a gap of 305 mm between the top edges of the top tray and a gap of 440 mm

between the bottom edges of the trays the bottom walls, a gap of 65 mm between the

edges of the trays and side the walls and doors of the cabinet to allow air to circulate to

regulate the temperature inside the incubator. The tray supports are mounted in as a H

shaped horizontal support mount of the unit.

3.3.5 Egg Tray Turning Mechanism

The four egg tray supports are mounted properly so that, they rock together freely at

least 30° in each direction from horizontal. The system can adjust by loosen the screws or

add washers under them to keep the strap from bind with the supports.

A rocker arm attached to the right end of the top support tray extends thru the top of

the case and is bent to form a handle of sorts. The bend for the handle limits tray rocking

to the right, a clamp on the arm inside the case limits the travel of rockers to the left.

Figure 3.8: Egg Tray Turning Mechanism


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DC gear motor with Egg tray turning mechanism used to rotate the egg tray at a

very low speed. It requires 12V/400mA DC power supply.

3.3.6 Egg Hatcher Tray

Hatcher tray is a tray with tray covers, where eggs were positioned after the 18th

day of incubation until they hatched. The external dimensions are 300 × 440 × 90 mm

PVC plastic tray. The hatching tray is 220mm above the bottom layer.

3.3.7 Circulating Fan

The circulating fan use for the purpose of circulating the hot air uniformly around

the chamber. Two DC brash less 12V, 0.6A fan is used to circulating the hot air from top

to bottom and bottom to top to make an air cycle inside the box. Fans are always kept on

during incubation.

3.3.8 Ventilation System

The developing embryo receives oxygen from the atmosphere and releases carbon-

dioxide; there is a ventilation hole with small fans to serves as heat and CO2 extractor and

the fan hole as oxygen in-let. Ventilation is provided automatically through holes pierced

in the sides of the incubator.

3.3.9 Water Supply and Water Pans

Water pans are placed at the bottom of the incubator to regulate humidity. Water

regulates the humidity inside the incubator. The fan blows warm air over a shallow pan of

water. The water evaporates, maintaining the high humidity but also cooling the air

somewhat. The surface area of the pan determines the humidity. For a higher humidity it

needs to increase the diameter of the evaporating pan.

This mechanical incubators imitate a hens natural brooding abilities by providing

an artificial micro-climate with the proper temperature, humidity, and ventilation, as well

as by allowing the eggs to be turned regularly.


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3.4 Embedded System Design of the Incubator

The development of the software, interface circuit and hardware design are known

as embedded system in which the software are developed and downloaded in

microcontroller chip to provide overall system functionality. The functional block diagram

of the embedded system is shown in Figure 3.9; certain factors such as cost, availability of

components, simplicity, functionality and reliability were put into consideration.

Figure 3.9: Microcontroller Based Forced Air Egg Incubator Controller Block Diagram


56

For measuring and automatic controlling temperature, humidity, ventilation and

egg turning, the Microcontroller Based Forced Air Egg Incubator Controller (MBFAEIC)

board designed and implemented, which is based on the PIC16F877A micro-controller,

DS1302 clock and the DS18B20, HSM20G, LM35 sensor. The input devices used inside

the incubator box are named as the Top Temperature sensor DS18B20 used to measure

temperature at top egg tray, the Bottom Temperature sensor DS18B20 used to measure

temperature at bottom egg tray, the incubator humidity sensor HSM-20G used to measure

incubation humidity and the real time clock/calendar used for getting real time to operate

egg tray turning motor timely and to keep incubation day. The input devices used outside

the incubator box are named as LM35 Temperature sensor used to measure outside room

temperature and humidity sensor hsm-20g used to measure outside room humidity. The

user interface consists of three push button named as Menu/Set, Up and Down are used to

set the temperature, humidity, Egg turning period , Clock setting and other parameter.

The design of this system includes two parts. These are the Electronic Hardware

Design and software development. For proper functionality of the system, these two parts

must agree with each other. The hardware and software design are discussed as follows:

3.4.1 Electronic Hardware Design The hardware unit consists of the following sub-unit:

The microcontroller unit, The Sensor Unit, The Real Time Clock calendar Unit, The Human Machine Interfacing unit, The Auto Saving Data Log in MS Excel Unit The Driver Unit and The Power Supply Unit.

These units are discussed below:

3.4.1.1 The Microcontroller Unit (MCU)

The microcontroller is a device which can make decision with the help of given

instruction. The microcontroller is called single chip microcomputer; it is a “one-chip-

solution”. In this forced air egg incubator implementation the microcontroller used to


57

controls, schedule and directs all the activities and behaviors based on the control program

written for it.

The 40 pin DIP microcontroller PIC16F877A form Microchip [51], satisfies the

criterion necessary for the Forced Air Egg Incubator application, used to control the

activities of all other sections. The Physical layout and Pin configuration PIC16F877A

microcontroller shown in Figure 3.10

(a) (b)

Figure 3.10: PIC16F877A Microcontroller (a) Physical Layout (b) Pin Configuration

The following basic criteria were considered in selecting this microcontroller for

the system. Ability to handle the task at hand efficiently and cost effectiveness; Maximum

operating speed the microcontroller can support; Power consumption; The number of I/O

pins and the easy of developing products around the chip, these include availability of

assembler, debugger, compiler and technical support Currently of the leading 8-bit

microcontrollers. The 8-bit microcontroller PIC16F877A was selected due to its good


58

features of being cheap and readily available in the market and the whole design circuit

can be simplified and easy for troubleshooting.

The PIC16F877A Features

It is 40 Pin Enhanced Flash Microcontrollers with High-Performance RISC CPU.

It has 8K×14 words of Flash Program Memory, 368×8 bytes of Data Memory (RAM) and

256×8 bytes of EEPROM Data Memory. 100,000 erase/write cycle Enhanced Flash

program memory typical. 1,000,000 erase/write cycle Data EEPROM memory typical.

Data EEPROM Retention is more then 40 years. It has 8-channel Analog-to-Digital

Converter (A/D) with 10-bit resolution, Synchronous Serial Port (SSP) with SPI (Master

mode) and I2C (Master/Slave), Universal Synchronous Asynchronous Receiver

Transmitter (USART/SCI) with 9-bit address detection., Brown-out detection circuitry for

Brown-out Reset (BOR). Watchdog Timer (WDT) with its own on-chip RC oscillator for

reliable operation. CMOS Technology Low-power, high-speed Flash/EEPROM

technology. Wide operating voltage range (2.0V to 5.5V). Low-power consumption.

Commercial and Industrial temperature ranges and Programmable code protection.

The Block Diagram PIC16F877A

The internal architectural block diagram of PIC16F877A shown in Figure 3.11.

3.4.2 The Sensor Unit

There are temperature sensors and humidity sensors have been used for measuring

the inside and outside temperature and humidity. The appropriate sensor selection depends

on factors such as the temperature range, required accuracy, environment, speed of

response, ease of use, cost, and interchange ability and so on. Due to the suitable electrical

characteristics for the measurement and control process, integrated circuit (IC) type’s

sensors are more suitable than the others also cost effective and available in local market.

Temperature Sensor

Temperature sensor is very important for egg incubator because it requires a

precise control of the temperature. To ensure a precise control of the temperature the first

requirement is precise and reliable temperature sensor.


59

There are many types of sensors to measure the temperature, depending on the

accuracy, the temperature range, speed of response, thermal coupling, the environment and

the cost. The new generation semiconductor integrated circuit sensors used in this project.

Figure 3.11: PIC16F877A Internal Block Diagram

Integrated circuit temperature sensors are semiconductor devices fabricated in a

similar way to other semiconductor devices such as microcontrollers. A power supply is

required to operate these sensors.


60

Integrated circuit semiconductor temperature sensors can be divided into the following categories:

(a) Analog temperature sensors

(b) Digital temperature sensors

(a) Analog sensors are further divided into: Voltage output temperature sensors

Current output temperature sensors

Analog sensors can either be directly connected to measuring devices (such as

voltmeters), or A/D converters can be used to digitize the outputs so that they can be used

in computer based applications.

Voltage output temperature sensors

This sensor provides a voltage output signal which is proportional to the temperature

measured. LM35

LM35 can measure temperature more accurately than a using a thermistor. The

LM35 generates a higher output voltage than thermocouples and may not require that the

output voltage be amplified. LM35 is a 3-pin device and it has two versions and they both

provide a linear output voltage of 10mV/ºC [52]. The pin configuration of LM 35 shown

in Figure 3.12. The temperature range of the "CZ" version is -20 ºC to +120 ºC while the

"DZ" version only covers the range 0 ºC to +100 ºC. The LM35 does not require any

external calibration or trimming and maintains an accuracy of +/-0.4oC at room

temperature and +/- 0.8 oC over a range of 0oC to +100oC. The popular LM35DZ

temperature sensor can operate at the maximum supply voltage of +35 V, but the sensor is

normally operated at +5 V. When operated at +5 V, the supply current is around 80 µA.

The typical accuracy is ± 0.6 ºC at +25 ºC.

The output voltage is a direct indication of the temperature in 10mV/ ºC. An A/D

converter used to digitize the output voltage to interface with computer based applications.

The output voltage from the sensor converted to a 10-bit digital number using the internal


61

ADC of the PIC16F877A. Since the voltage to be measured by the ADC ranges from 0 to

1.0V that corresponds to temperature ranges from 0ºC to 100 °C.

Figure 3.12: LM35Voltage Output Temperature Sensor

ADC converts to mV: 1024 adc value means= 5000mV 1 adc value means= 5000mV/1024 ADCResult adc value means= (5000/1024* ADCResult) mV mV convert to º C: 10 mV is equivalent to 1º C 1 mV is equivalent to 1º C/10 (5000/1024* ADCResult) mV is equivalent to (5000/1024* ADCResult)*1/10º C = (0.48828125* ADCResult) º C

In this project one LM35DZ temperature sensor is used to measure the Incubation

room temperature.

(B) Digital Output Temperature Sensors

The digital output temperature sensors produce digital outputs which can be

interfaced directly to computer-based equipment. The outputs are usually non-standard

and the temperature can be extracted by using suitable algorithms. Digital temperature

sensors usually provide 1-wire or 3-wire interface, I2C bus, SPI bus, or some other to the

outside world.


62

DS18B20 DS18B20 is direct-to-digital temperature sensor which also incorporates digitally

programmable thermostat outputs [53]. The resolution of the temperature sensor is user-

configurable to 9, 10, 11, or 12 bits, corresponding to increments of 0.5°C, 0.25°C,

0.125°C, and 0.0625°C, respectively. The default resolution at power-up is 12-bit. The

DS18B20 communicates over a 1-Wire bus that by definition requires only one data line

(and ground) for communication with a central microprocessor. It has an operating

temperature range of -55°C to +125°C and is accurate to ±0.5°C over the range of -10°C

to +85°C. For continuous control of the temperature, the temperature sensor DS18B20 is

suitable for precisely measure temperatures in wet environments.

Pin assignment, pin description and block diagram of DS18B20 shown in Figure

3.13, Figure 3.14 and Figure 3.15.

Figure 3.13: DS18B20 Digital Output Temperature Sensors

Figure 3.14: DS18B20 Detail Pin Description


63

Figure 3.15: DS18B20 Block Diagram

Connection

The typical connection diagram of DS18B20 to a Microcontroller is shown in

Figure 3.16 and Physical sensor connection shown in Figure 3.17.

Figure 3.16: DS18B20 Typical Connection

37.5DQ2 VCC3

GND1

U1

DS18B20

R14k7

To Microcontroller


64

Figure 3.17: Physical Sensor Connection

DS18B20 Memory.

Scratchpad is 9 bytes of SRAM that organized as figure shown in Figure 3.18. The

first two bytes (byte 0 and byte 1) are read-only memory that contain the LSB and the

MSB of the temperature register. Bytes 2 and 3 provide access to TH and TL registers.

Byte 4 is a configuration register. Bytes 5,6 and 7 are reserved. Byte 8 is read-only and

contains CRC code (cyclic redundancy check) for byte 0 through byte 7 of the scratchpad.

Figure 3.18: DS18B20 Memory Map

The output temperature data from DS18B20 is calibrated in degree centigrade and

the default resolution at power up is 12-bit. The temperature register format shown in

Figure 3.19, where as sign bits (S) indicate if the temperature is positive (S=0) or negative

(S=1).


65

Figure 3.19: Temperature/Data Relationship Programming steps of DS18B20 To access the DS18B20's data, 3 steps sequence as follows is need. 1. Initialization: All transactions on the 1-wire bus begin with an initialization sequence.

It consists of a reset pulse transmitted by the bus master followed by presence pulse

transmitted by the slave. Timing for the reset and presence pulse is shown in Figure 3.20.

Figure 3.20: DS18B20 Initialization Timing

2. Issue a ROM Command: Issue a ROM command after the bus master has detected a

presence pulse. ROM commands are : Search ROM[F0h], Read ROM[33h], Match

ROM[55h], Skip ROM[CCh] and Alarm Search[ECh].


66

3. Issue a DS18B20 Function Command: Issue a DS18B20 function command after a

ROM command. A ROM command is to select which DS18B20 that the master wants to

communicate with. A function command allows the master to read and to write from the

DS18B20's scratchpad, etc. DS18B20 function commands are: Convert T[44h], Write

Scratchpad[4Eh], Read Scratchpad[BEh], Copy Scratchpad[48h], Recall E2[B8h], and

Read Power Supply[B4h]. It is very important to follow this sequence every time the

DS18B20 is accessed. Exceptions to this rule are Search ROM[F0] and Alarm Search[EC]

commands. The master must return to step 1 after issue either of those ROM commands.

In this project two DS18B20 temperature sensor are used to measure the inside

temperature of egg incubator.

Humidity Sensor

Absolute Humidity is the mass of water vapor divided by the mass of dry air in a

volume of air at a given temperature. The hotter the air is, the more water it can contain.

Relative humidity is the ratio of the current absolute humidity to the highest possible

absolute humidity which depends on the current air temperature.

A reading of 100 % relative humidity means that the air is totally saturated with

water vapor and cannot hold any more, creating the possibility of rain. This doesn't mean

that the relative humidity must be 100 percent in order for it to rain. It must be 100 percent

where the clouds are forming, but the relative humidity near the ground could be much

less.

Due to the suitable electrical characteristics for the measurement and control

process, integrated circuit (IC) type’s humidity sensors are more suitable than the others.

HSM-20G

HSM-20G is a Humidity and Temperature sensor [54]. It converts the relative

humidity to standard voltage output. Its storage relative humidity (RH) Range 0 to 99%

RH, measurement accuracy ±5% RH. Output voltage range DC 1-3.19V. Input voltage

range is DC 5.0±0.2V, Operating Current (Maximum) is 2mA.


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The HSM-20G humidity sensor shown in Figure 3.21 are cost effective (cost

around 300 taka) and available in local market.

(a) (b)

Figure 3.21: HSM20G Humidity Sensor (a) Front View, (b) Back View

HSM-20G is an analog sensor. HSM-20G, datasheet have given output voltage

data from the humidity sensor for certain relative humidity values and also have a plotted

graph too. Same with the Temperature Sensor this sensor too is connected to an ADC

(analog to digital converter) in order to get the output in digital.

Typical Response of HSM-20G at 25ºC

The typical response of Relative humidity verses output voltage at 25ºC of HSM-

20G shown in Figure 3.22(a).

(a) Relative Humidity Verses Output Voltage Plot [54] (b) Linear Equation for Relative Humidity, % RH

Figure 3.22: Relative Humidity Response of HSM-20G


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Standard Characteristics

The module of HSM-20G is essential for those applications where the relative

humidity can be converted to standard voltage output. The Relative humidity verses output

voltage of HSM-20G shown in Table 3.3[54]. By using Table 3.3 the suitable linear

equation for determine the Relative Humidity from the output voltage of HSM-20G is

%RH = (30.85 × Output Voltage - 11.50) shown in Figure 3.22 (b).

Table 3.3: Relative Humidity Verses Output Voltage Relation

Relative

Humidity,

%RH

10

20

30

40

50

60

70

80

90

Output

Voltage,

V

0.74V

0.95V

1.31V

1.68V

2.02V

2.37V

2.69V

2.99V

3.19V

In order to use this sensor, a connector cable was build to connect the sensor to main

MBFAEIC control board. The Physical connection of sensor HSM20G shown in Figure

3.23, the 3-pin header was connected to the circuit required such that:

(-) negative pin connects to GND

(+) positive pin connects to Vcc

H (humidity sensor) pin connects to ADC.

Figure 3.23: Physical Sensor Connection (HSM20G)

For continuous control of the humidity, the humidity sensor hsm-20g is the right choice and suitable for it’s precisely measure humidity. One hsm-20g humidity sensor is used to measure the current humidity inside the egg incubator and another humidity sensor hsm-20g is used to measure the incubation room humidity.


69

3.4.3 The Real Time Clock (RTC) Unit The Real Time Clock (RTC) unit provides real time measure which the

microcontroller used to maintain the automatic schedule egg turning system and to keep

incubation period of the egg.

The DS1302 real time clock was used for this unit [55]. It is a trickle-charge

timekeeping chip contains a real-time clock/calendar and 31 bytes of 31 x 8 Battery-

Backed General-Purpose static RAM [56]. The real-time clock/calendar provides seconds,

minutes, hours, day, date, month, and year information with Leap-Year Compensation

Valid Up to 2100. The end of the month date is automatically adjusted for months with

fewer than 31 days, including corrections for leap year. The clock operates in either the

24-hour or 12-hour format with an AM/PM indicator. It can operate in full operation at

2.0V to 5.5V. The DS1302 pin diagram shown in Figure 3.24.

Figure 3.24: DS1302 Pin Diagram

It communicates with PIC16F877A microcontroller via synchronous serial

communication. Only three wires are used to communicate with the clock/RAM are CE,

I/O (data line), and SCLK (serial clock). Data are transferred to and from the clock/RAM

in a Multiple-Byte Burst of up to 31 bytes for Read or Write of Clock or RAM Data. PIN DESCRIPTION

PIN NAME FUNCTION 1

VCC2

Primary Power-Supply Pin in Dual Supply Configuration. VCC1 is connected to a backup source to maintain the time and date in the absence of primary power. The DS1302 operates from the larger of VCC1 or VCC2. When VCC2 is greater than VCC1 + 0.2V, VCC2 powers the DS1302. When VCC2 is less than VCC1, VCC1 powers the DS1302.

2 X1

Connections for Standard 32.768kHz Quartz Crystal. 3 X2


70

4

GND

Ground 5

CE or

RST

Input. CE signal must be asserted high during a read or a write. This pin has an internal 40kΩ pull-down resistor to ground.

6 I/O

Input/Push-Pull Output. The I/O pin is the bidirectional data pin for the 3-wire interface. This pin has an internal 40kΩ pull-down resistor to ground.

7 SCLK

Input. SCLK is used to synchronize data movement on the serial

interface. This pin has an internal 40kΩ pull-down resistor to ground.

8 VCC1

Low-Power Operation in Single Supply and Battery-Operated Systems and Low-Power Battery Backup. In systems using the trickle charger, the rechargeable energy source is connected to this pin.

Uninterrupted Power

A lithium battery was used to provide a source of alternative power supply to the

RTC. It is used to maintain accurate time even when there is no power supply to the

system. A supper capacitor can be used in case of uninterrupted power. The capacitor will

be charged through the DS1302 chip. The charge (true) method will charge the capacitor

which works only for a SuperCap.

Figure 3.25: Wiring Diagram for the DS1302

RST

RST

SCLKDTA

DTASCLK

RA0/AN02

RA1/AN13

RA2/AN2/VREF-4

RA4/T0CKI6

RA5/AN4/SS7

RE0/AN5/RD8

RE1/AN6/WR9

RE2/AN7/CS10

OSC1/CLKIN13

OSC2/CLKOUT14

RC1/T1OSI/CCP2 16

RC2/CCP1 17

RC3/SCK/SCL 18

RD0/PSP0 19

RD1/PSP1 20

RB7/PGD 40RB6/PGC 39RB5 38RB4 37RB3/PGM 36

RB2 35RB1 34RB0/INT 33

RD7/PSP7 30RD6/PSP6 29RD5/PSP5 28RD4/PSP4 27RD3/PSP3 22RD2/PSP2 21

RC7/RX/DT 26RC6/TX/CK 25RC5/SDO 24RC4/SDI/SDA 23

RA3/AN3/VREF+5

RC0/T1OSO/T1CKI 15

MCLR/Vpp/THV1

PIC16F877A

PIC16F877

33k

VCC

X1CRYSTAL

C5

100n

C6

100n

T_out_HSM20GH_out_HSM20G

LM35_1H_in_HSM20G

C3100n

2.2k

RST 5

SCLK 7

I/O 6

X12

X23

VCC1 8

VCC2 1

U_DS1302

DS1302

12

BAT13.2V

12

XT1

XT_PCB

VCC


71

The DS1302 uses an external 32.768 kHz crystal. The oscillator circuit does not

require any external resistors or capacitors to operate.

Figure 3.26: Typical PC Board Layout for Crystal

It is highly recommended to make the crystal-to-pin connection length as short as

possible and avoid routing signals in the crosshatched area (upper left hand quadrant) of

the package unless there is a ground plane between the signal line and the package as

shown in Figure 3.26. The time and calendar information is obtained by reading the

appropriate register bytes. Table 3 illustrates the RTC registers.

The time and calendar are set or initialized by writing the appropriate register

bytes. The contents of the time and calendar registers are in the binary-coded decimal

(BCD) format. The day-of-week register increments at midnight. Values that correspond

to the day of week are user-defined but must be sequential (i.e., if 1 equals Sunday, then 2

equals Monday, and so on.). Illogical time and date entries result in undefined operation.

When reading or writing the time and date registers, secondary (user) buffers are used to

prevent errors when the internal registers update. When reading the time and date

registers, the user buffers are synchronized to the internal registers the rising edge of CE.

Clock/Calendar Burst Mode

The clock/calendar command byte specifies burst mode operation. In this mode,

the first eight clock/calendar registers can be consecutively read or written (shown in

Figure 3.27) starting with bit 0 of address 0.


72

Figure 3.27: Register Address / Definition

The main microcontroller PIC16F877A has provision for timing but a separate

RTC is used because of its lower power consumption and it frees the main microcontroller

for time critical tasks and it is accurate.

3.4.1.4 The User Interface

The user interface provides the user an interface for configuration of the system.

The configuration of the device includes setting the egg in setter mode, hatcher mode,

temperature, humidity, time and the incubation period by using user friendly Human

Machine Interfacing Menu Program (HMIMP).

To achieve this user interface, three Human Machine Interfacing push button

(Menu/Set, Up and Down) and a LCD display unit are used to display general incubation

information and to set the temperature, humidity, Egg turning period , Clock setting and

other parameter.

Human Machine Interfacing Push Buttons:

The most common type of input device push-button is used as user input

interfacing device, where the user can change the state of an input pin by pressing a

button. Basically, button input can be in two different ways as Active HIGH and Active

LOW.


73

The Human Machine Interfacing Push Buttons are connected as Active HIGH

configurations. In this configuration the button is connected between the supply voltage

and the port pin. A resistor (this is also called a pull-down resistor) is connected between

the port pin and ground. Normally, the port pin is at logic 0. When the button is pressed

the port pin goes to the supply voltage which is logic 1.When switch S1 is open, there is

practically no current flowing through the pull-down resistors. Therefore, the voltage at

point A is the same as ground (0 volts), since there is no voltage drop across pull-down

resistors. The PIC pin is held to LOW (0 volts) until the switch is closed, at which point

the PIC pin goes HIGH (+5 volts).

Figure 3.28: Human Machine Interfacing Push Buttons Control Circuitry

If nothing is connected to the input pin, the voltage at the input is considered

floating, i.e., some unknown voltage between 0 and +5 volts. Pull-down resistor will

allow the pin to keep a steady state at 0 volts until switch S1 is closed.

D7

D6 D7

D5

D4

ERS

D6D5D4E

RS

MENU

DOWNUP

DOWN

UPMENU

RA0/AN02

RA1/AN13

RA2/AN2/VREF-4

RA4/T0CKI6

RA5/AN4/SS7

RE0/AN5/RD8

RE1/AN6/WR9

RE2/AN7/CS10

OSC1/CLKIN13

OSC2/CLKOUT14

RC1/T1OSI/CCP2 16

RC2/CCP1 17

RC3/SCK/SCL 18

RD0/PSP0 19

RD1/PSP1 20

RB7/PGD 40RB6/PGC 39RB5 38RB4 37RB3/PGM 36RB2 35RB1 34RB0/INT 33



RA3/AN3/VREF+5

RC0/T1OSO/T1CKI 15

MCLR/Vpp/THV1

PIC16F877A

PIC16F877

33k

VCC

X1CRYSTAL

C5

100n

C6

100n

RB0DQ1


LM35_1H_in_HSM20G

C3100n

2.2k

D7

14D

613

D5

12D

411

D3

10D

29

D1

8D

07

E6

RW5

RS

4

VSS

1

VDD

2

VEE

3

A15

K16

LCD1LCD_PCB

VCC

MENU DownUP 100n

> <

10k 10k 10k

LCD Display


74

When the switch is close, then mAK

VRVI 5.0

105

current is flowing through

pull-down resistor. Therefore the voltage at PIC pin the same as +5 volts

( VKmAIRV 5105.0 ). The PIC pin is held to HIGH (5 volts) until the switch is opened,

at which point the PIC pin goes LOW.

The contact bounce is a common problem with mechanical switches. All

mechanical switches ‘bounce’ when the switch opens or closes. This means that the switch

contacts ‘bounce’ against each other before settling. When the contacts strike together,

their momentum and elasticity act together to cause bounce. The result is a rapidly pulsed

electrical current instead of a clean transition from zero to full current. It mostly occurs

due to vibrations, slight rough spots and dirt between contacts. When this signal is passed

to a PIC microcontroller, the microcontroller can recognize this as multiple button presses,

which will cause the application software to act as if multiple, very fast button presses

have taken place.

Figure 3.29: The Switch Contacts Bounce

There are two common methods used for debouncing button inputs.

Figure 3.30: The Ideal Waveform of Switch Contact

One way to eliminate this switch-bouncing problem is to delay reading the input

after the switch state changes by introducing a 10 ms delay before read the state of the


75

switch. The second method is to poll the line continually and wait for 20 ms to go by

without the line changing state.

This problem may be easily solved by connecting a simple RC circuit or simply a

capacitor to suppress quick voltage changes. Since the bounce period is not defined, the

values of components are not precisely determined. In most cases it is recommended to

use the values as shown in figure below.

LCD Display Unit

The number of information to be displayed was put into consideration in selecting

the LCD. A twenty character by four lines liquid crystal display (LCD) was used for this

unit. The display unit allows the user to visualize settings during configuration and the

system status during operation. During normal operation, the LCD display is in display

mode. When menu button is pressed the LCD display is in Set mode. In display mode the

first line displays the current temperature T1 and T2 inside the incubator box measurement

by Top Temperature sensor DS18B20 which is placed at top egg tray and Bottom

Temperature sensor DS18B20 which is placed at top of bottom egg tray respectively. The

second line displays the current humidity inside the incubator box measurement by

humidity sensor HSM20G display as H and Egg incubation Setting temperature for that

particular egg as Set. The third line displays the room current temperature and humidity as

R outside the incubator box measurement by Top Temperature sensor LM35 and humidity

sensor HSM20G which are placed outside the incubator box and incubation day. As well

as the number of days the egg has been in the incubator are displayed. The forth line

displays the current time, date, month year and day of the week as hh:mm:ss, dd:mm:yy

and day format.

3.4.5 Auto Saving Data Logging in MS Excel

All the incubation parameters during the incubation period are logged in Microsoft

excel, which are very useful and realistic for getting right prediction from output result to

improve incubator operation for optimum performance. PIC16F877A microcontroller has

built in Universal Synchronous Asynchronous Receiver Transmitter (USART) serial

communication system with 9-bit address detection. In this Egg Incubator project RS-232


serial communication use to send and receive data between a PIC microcontroller and a

PC. By using RS232 to USB converter incubation data are store in laptop during test

hatching.

A MAX 232 was used to provide voltage matching of the different types of logic

used in the microcontroller and those in the P C, because of voltage level differences of

the devices. The Max 232 is a 16 pin dip IC that is used to convert CMOS voltages to TTL

voltages. An example of a signal on both sides of a MAX232 converter chip:

Figure 3.31: Signal as it Leaves the PIC Pin (The PIC Side of the MAX232)

Figure 3.32: Signal on an RS232 Line (The PC Side of the MAX232)

Figure 3.33: RS232 Data Logger Circuit A straight-through cable is used to connect a PC to a remote egg incubator. 3.4.1.6 The Driver Unit

The microcontroller cannot directly drive the relays to which the actuators are

connected as it could not supply the required current needed to drive the relay. In


77

designing the current driver the switching current for the relays was put into consideration.

The PIC Microcontroller output pins can either act as a source of current or as a sink for

current to drive electronic devices. The maximum output current sunk or source by any

I/O pin is 25mA.

The transistor connects as the High Active Switch (Logical High) also known as

low side switch using NPN transistor.

Buzzer and Relay interface:

Figure 3.34: Buzzer Circuit

Figure 3.35: Interfacing Relay with Microcontroller

Q_BZBC547

R_BZ1k

BZREX

T_v

BD1351k

REL

AY1

(H1)

12

+12V

123


78

Figure 3.36: Interfacing Relay with Microcontroller with Opto-Isolator

3.4.1.7 The Power Supply Unit

The PSU for the system should be capable of providing the required supply voltage

and current to all the various sub-units in the system. Two independent power supply card

is designed to provide electrical noise and spike free power to controller unit. One power

supply card to supply regulated +5V for microcontroller, sensors, clock and display card

and power supply card to supply +12V for fan, regulated +12V for the relay drive and egg

turning motor. The PSU is based on a full wave bridge rectifier including suitable

smoothing filters, regulator and an appropriately rated transformer.

Figure 3.37: Independent +5V Regulated Power Supply

BD135

1k

GND(12V)

560

12

+12V

A

K

C

E

B1

2 4

56

U1

4N25

R1220

GND(12V)

+12V

RL212V

R210k

R410k

GND(12V)

123

J1

TBLOCK-I3

REL

AY3

(H1)

D11N4007

D2

1N4007

D31N4007

D4

1N4007

C1470uF,35V

C20.1u

VI1 VO 3

GND

2 U1

7805

C3470u

C40.1u

VCC

AC

AC


79

Figure 3.38: Independent +12V Regulated Power Supply

Beside this power supply computer ATX power supply also suitable and used in

this project.

In order to enable the PIC16F877A microcontroller to operate properly it provide

Power Supply, Reset Signal and Clock Signal is called minimum hardware requirements

of PIC microcontroller. The device operates at 8MHz, so a high execution speed achieved

with a single chip microcontroller unit.


80

3.4.1.8 Overall Circuit Diagram of the Incubator The overall circuit diagram of the entire five units is shown in Figure 3.39 and

Figure 3.40 (Part-1 and Part-2).

Figure 3.39: Overall Circuitry of the MCBFAEI (Part-1)

D7

D6 D7

D5

D4

ERS

D6D5D4E

RS

RST

RST

SCLKDTA

DTASCLK

MENU

DOWNUP

DOWN

UPMENU

BUTTOM_HEATER_1

BUTTOM_HEATER_2TOP_HEATER_1TOP_HEATER_2

EGG_TURNING_MOTORHUMIDIFIER_CONTROL

VENTILATION_MOTOR

RA0/AN02

RA1/AN13

RA2/AN2/VREF-4

RA4/T0CKI6

RA5/AN4/SS7

RE0/AN5/RD8

RE1/AN6/WR9

RE2/AN7/CS10

OSC1/CLKIN13

OSC2/CLKOUT14

RC1/T1OSI/CCP2 16

RC2/CCP1 17

RC3/SCK/SCL 18

RD0/PSP0 19

RD1/PSP1 20

RB7/PGD 40RB6/PGC 39RB5 38RB4 37RB3/PGM 36RB2 35RB1 34RB0/INT 33



RA3/AN3/VREF+5

RC0/T1OSO/T1CKI 15

MCLR/Vpp/THV1

PIC16F877A

PIC16F877

33k

VCC

X1CRYSTAL

C5

100n

C6

100n

RB0DQ1

RC6/Tx


LM35_1H_in_HSM20G

C3100n

2.2k

D7

14D

613

D5

12D

411

D3

10D

29

D1

8D

07

E6

RW5

RS

4

VSS

1

VDD

2

VEE

3

A15

K16

LCD1LCD_PCB

RST 5

SCLK 7

I/O 6

X12

X23

VCC1 8

VCC2 1

U_DS1302

DS1302

12

BAT13.2V

12

XT1

XT_PCB

VCC

VCC

MENU DownUP 100n

> <

10k 10k 10k

RC6/TXT1IN 11

R1OUT 12

T2IN 10

R2OUT 9

T1OUT14

R1IN13

T2OUT7

R2IN8

C2+

4

C2-

5

C1+

1

C1-

3

VS+2

VS-6

U412

MAX232

C31

1uF

C4

1uF

C61uF

+5v

C51uF

ERROR

TXD 3

RXD 2

CTS 8

RTS 7

DSR 6

DTR 4

DCD 1

RI 9

P1

COMPIM

Q_BZBC547

R_BZ1k

+12V

Bus

DQ2

Data Logger

Real Time Clock

LCD Display


81

Figure 3.40: Overall Circuitry of the MCBFAEI (Part-2)

TOP_HEATER_2

BUTTOM_HEATER_2

EGG_TURNING_MOTOR

TOP_HEATER_1

BUTTOM_HEATER_1

VENTILATION_MOTOR

HUMIDIFIER_CONTROL

37.5DQ2 VCC3

GND1

U1

DS18B20

R14k7

VCC

DQ1

TOP_HEAT_SENSOR

36.7DQ2VCC3

GND1

U112

DS18B20

R1124k7

VCC

BOTTOM_HEAT_SENSOR

VCC

H

H

BD1351k

12

+12V

BD135

1k

12

+12V

Heater

T

OV1OVEN

Heater

T

OV2OVEN

BD1351k

560 R

12

+12V

BD135

1k

12

+12V

Heater

T

OV1OVEN

Heater

T

OV2OVEN

AC 230 Volt (L)

Heater

T

OV3OVEN

BD1351k

12

+12V

BD135

1k

12

+12V

BD1351k

12

+12V +1

2V

+12V

H_IN_HSM20G

Bus

DQ2

EGG INCUBATOR

EGG INCUBATOR

VENTILATION FAN

TOP_HEATER_1 TOP_HEATER_2

BUTTOM_HEATER_2BUTTOM_HEATER_1 HUMIDIFIER_CONTROL

Busses Mode

VCC

HH_OUT_HSM20G

Room Humidity Sensor

LM35_1

37.5

3

1

VOUT2

U4LM35

Room Temperature Sensor

EGG INCUBATOR

EGG INCUBATOR

Incubator Humidity Sensor

Egg Turning Motor


82

3.4.1.9 IR Remote Control for Egg Turning System

IR remote control also use for operating the egg turning mechanism. For this

purpose SIRC Protocol based IR transmitter and receiver is designed in this project works

using PIC microcontroller. SIRC Protocol is selected for this project work because of

Sony use SIRC Protocol and Sony remote control(Rx) are locally available very low cost

approximately 40 taka to 100 taka. To make a unique egg turning mechanism SIRC

Protocol based IR transmitter with device code 4 is designed also receiver circuit is

designer for a device code 4.

The PIC microcontroller PIC12F675 used for IR remote control egg turning system

has built-in oscillator circuits and they do not require any external timing components. The

built-in oscillator is usually set to operate at 4 MHz and is selected during the

programming of the device. A factory-calibrated oscillator constant is loaded into the last

location of the memory. By copying this constant value into the oscillator register we can

have a more accurate 4 MHz clock frequency for our microcontroller.

Figure 3.41: IR Remote Control Transmitter and Receiver System SIRC Protocol

Figure 3.42: Modulation of SIRC Protocol


83

The SIRC protocol uses a pulse width encoding of the bits. The pulse representing

a logical “1” is a 1.2ms long burst of the 38kHz to 40kHz carrier, while the burst width for

a logical “0” is 0.6ms long. All bursts are separated by a 0.6ms long space interval. The

recommended carrier duty-cycle is 1/4 or 1/3.

Features

5-bit address and 7-bit command length (12-bit protocol)

Pulse width modulation

Carrier frequency of 38kHz to 40kHz

Bit time of 1.2ms or 0.6ms

Figure 3.43: SIRC Protocol Signal Pattern

The picture above shows a typical pulse train of the SIRC protocol. With this

protocol the LSB is transmitted first. The start burst is always 2.4ms wide, followed by a

standard space of 0.6ms. Apart from signaling the start of a SIRC message this start burst

is also used to adjust the gain of the IR receiver. Then the 7-bit Command is transmitted,

followed by the 5-bit Device address. In this case Address 1 and Command 19 are

transmitted. Commands are repeated every 45ms (measured from start to start) for as long

as the key on the remote control is held down.


84

3.4.2 Software Development

Software Development deals with developing of software for the control of

parameters such as temperature, humidity, ventilation and eggs turning of incubator to

provide proper embryonic development environment. Software is an integral part the

control system; it interacts with hardware to carry out different functions which are

responsible for the control of parameters.

Flowcharts has been developed in this part depicting step by step development of

the software which issue instructions to various components of the hardware thereby

making monitoring and control of parameters efficient and automatic.

3.4.2.1 Main Program Flow of the System

The main program flow of the microcontroller based forced air egg incubator

controller (MBFAEIC) is shown in Figure 3.44.

Figure 3.44: Main Program Flow of the Incubator


85

When the system power ON, then MCU execute main loop and LCD display is in

incubator operation and display. When menu button is pressed then process goes to Menu

program.

3.4.2.2 Block Diagram for Menu Program

User friendly Human Machine Interfacing Menu Program (HMIMP) is

implemented. The user interface consists of three push button (Menu/Set, Up and Down)

and display unit. A twenty character by four lines liquid crystal display (LCD) display unit

allows the user to visualize settings during configuration and the system status during

operation. set point temperature, set point humidity, top tray temperature, bottom tray

temperature, room temperature, inside humidity, outside humidity, real time clock,

calendar, first heater sensitivity, second heater sensitivity, egg turning motor on off

condition, egg turning interval, egg turning motor on time and incubation day in the

incubator are displayed. These whole processes can be done as flowing block diagram

shown in Figure 3.45 and Figure 3.46 (Part 1and Part 2).

Figure 3.45: Human Machine Interfacing Menu Program (HMIMP) Operation (Part 1)


86

Figure 3.46: Human Machine Interfacing Menu Program (HMIMP) Operation (Part 2)


87

3.4.2.3 DS18B20 Temperature Sensors Read and Process Sub-Program

This sub-program is used to read DS18B20 Temperature Sensors data and also

convert the data to degree Celsius. There are two DS18B20 Temperature Sensors inside

the incubator to control incubation temperature.

3.4.2.4 LM35 Temperature Sensors Read and Process Sub-Program

This sub-program is used to read LM35 temperature Sensors data and also convert

the data to degree Celsius. There is one LM35 Temperature Sensor to measure incubation

room temperature.

3.4.2.5 Humidity Sensors Read and Process Sub-Program

This sub-program is used to read HSM20G Humidity Sensor data and also convert

the data to relative humidity (%r H). There are two HSM20G Humidity Sensors, used

inside the incubator to control incubation humidity and to measure incubation room

humidity.

3.4.2.6 Temperature Control Sub-Program

This sub-program is used to control temperature inside the egg incubator. There

are two DS18B20 Temperature named as Top temperature and Bottom temperature

Sensors inside the incubator.

T1 is the value from the Top temperature sensor in ºC. Top_Temp is T1×10

T2 is the value from the Bottom temperature sensor in ºC. Bottom_Temp is T2×10

Also, there are four Heating elements:

Two Heating elements situate on the top of the incubator named as

Top_Heater-1 and Top_Heater-2.

Another Two Heating elements situate on the bottom of the incubator named as

Bottom _Heater-1 and Bottom _Heater-2.


88

Incubator_Set_Temp is Egg Incubation Temperature (let, Incubator_Set_Temp= 37.5ºC)

Set_Temp is Incubator_Set_Temp×10 (So, Set_Temp = Incubator_Set_Temp×10= 375)

Fine_Tune_Temp, m. is first Heater-1 ON temperature factor. (When, m is 3

then temperate is 0.m= 0.3ºC)

Tune_Temp,n is second Heater-2 ON temperature factor. (When, n is 8 then

temperate is 0.n= 0.8ºC, )

Algorithm for Temperature Control Sub-program

1. Input Incubation Temperature, Set_Temp.

2. Input First Heating Element Fine Tune Temperature, Fine_Tune_Temp, m.

3. Input Second Heating Element Tune Temperature, Tune_Temp, n.

4. Input Top Temperature, Top_Temp.

5. Input Bottom Temperature, Bottom_Temp.

6. If ((Top_Temp) =< (Set_Temp - Fine_Tune_Temp, m)) Then, Top_Heater-1(40W) = ON 7. If ((Top_Temp) =< (Set_Temp - Tune_Temp, n)) Then, Top_Heater-2(60W) = ON 8. If ((Top_Temp) => (Set_Temp)) Then, Top_Heater-2(60W) = OFF 9. If ((Top_Temp) > (Set_Temp)) Then, Top_Heater-1(40W) = OFF 10. If ((Bottom_Temp) =< (Set_Temp - Fine_Tune_Temp, m)) Then, Bottom_Heater-1(40W) = ON 11. If ((Bottom_Temp) =< (Set_Temp - Tune_Temp, n)) Then, Bottom_Heater-2(60W) = ON 12. If ((Bottom_Temp) => (Set_Temp)) Then, Bottom_Heater-2(60W) = OFF 13. If ((Bottom_Temp) > (Set_Temp)) Then, Bottom_Heater-1(40W) = OFF


The MBFAEIC relay contact ON and OFF the heating elements at temperatures of the set point. The m and n frequent switching (or bouncing) of the controlled equipme

Temperature Control sub

Figure

Microcontroller Based Forced Air Egg Incubator

89

The MBFAEIC relay contact ON and OFF the heating elements at temperatures of m and n extent of the difference is known as hysteresis and prevents too

frequent switching (or bouncing) of the controlled equipment.

Temperature Control sub-program flow chart is shown in Figure

Figure 3.47: Temperature Control Sub-Program

Microcontroller Based Forced Air Egg Incubator

The MBFAEIC relay contact ON and OFF the heating elements at temperatures of extent of the difference is known as hysteresis and prevents too

Figure 3.47.


90

3.4.2.7 Humidity Control Sub-Program

The humidity control sub-program flowchart is Figure 3.48:

Figure 3.48: Humidity Control Sub-program 3.4.2.8 Egg Turning Control Sub-Program

This sub-program is used to control the egg tray turning motor based on predefine

turning schedule and real time clock.

3.4.2.9 Ventilation Control and Alarm System Sub-Program

Ventilation Control and Alarm System Sub-Program is used to control ventilation

window and ventilation fan are installed to control proper environmental inside the

incubator. Alarm system help the farmer to is used to take necessary action during

unavailable circumstance. It will give long beep when temperature and humidity is higher


91

than required level and short beep when temperature and humidity is lower than required

level.

3.4.2.10 IR Remote Control Transmitter

The PIC16F628A microcontroller is used for IR remote control transmitter. The

built-in oscillator is usually set to operate at 4 MHz and is selected during the

programming of the device. A factory-calibrated oscillator constant is loaded into the last

location of the memory. SIRC protocol based modified IR Transmitter with egg incubator

proposed device code-4 is designed for this incubator.

3.4.2.11 IR Remote Control Receiver

SIRC protocol based IR receiver is designed for and used for operating the egg

turning mechanism.

3.4.2.12 Program Coding

In the design and development of microcontroller based forced air egg incubator

controller, PicBasic Pro Software has been used, it is a Basic compiler for PICs from

microEngineering Labs and MicroCode Studio Plus an IDE from another vendor that

provides a Windows interface, a program editor, an in-circuit debugger, and boot loading

software. The control program for the microcontroller was written in Basic language for

code economy and speed reasons. The overall process includes writing, compiling,

assembling, running, and testing the program. PBP installation typically includes

PICBASIC PRO Compiler, Mecanique's MicroCode Studio IDE, Microchip's MPLAB

IDE, and Microchip's MPASM assembler [56-60].

3.4.2.13 Chips Programming

The PicBasic Pro™ compiler converts the user written BASIC code to assembly

code. It then launches MPLAB assembler which converts the assembly code to a hex file.

Top 2005 programmer is used in chips programming step, when the program is written to

the PIC chip the hex code is converted to binary machine code, which is the only code that

the CPU can understand.


92

3.5 PCB Design, Fabrication and Electrical Wiring

The PCBs are designed by using Proteus ISIS to Netlist transfer to ARES. Printed

PCB is etching using toner transfer process then fabricates component and PCBs to a

suitable box.

3.5.1 MBFAEIC Motherboard

The Microcontroller Based Forced Air Egg Incubator Controller (MBFAEIC)

Motherboard build-in with the microcontroller unit and the real time clock-calendar, also it

have interfacing facility of others units like HMI unit, the auto saving data log unit, the

driver unit and the power supply unit. The MBFAEIC motherboard Bottom Copper view,

Top view and 3D visualization shown in Figure 3.49, Figure 3.50 and Figure 3.51.

Figure 3.49: MBFAEIC Motherboard (Bottom Copper View)

Figure 3.50: MBFAEIC Motherboard (Top View)


93

Figure 3.51: MBFAEIC Motherboard (3D Visualization using ARES Professional) 3.5.2 PC Interface Card

The PC Interface Card (Top view, Bottom Copper view and 3D visualization)

shown in Figure 3.52.

Figure 3.52: PC Interface Card (Top View, Bottom Copper View and 3D Visualization)


94

3.5.3 Relay Driver Card

The four in one Relay Driver Card (Top view and Bottom Copper view and 3D

visualization) shown in Figure 3.53 and Figure 3.54.

Figure 3.53: Relay Driver Card (Top view and Bottom Copper view)

Figure 3.54: Relay Driver Card (3D Visualization)

The single Relay Driver Card with opto-isolator (Top view, Bottom Copper view

and 3D visualization) shown in Figure 3.55.

Figure 3.55: Relay Driver Card with Opto-isolator (Top View, Bottom Copper View and 3D Visualization)


95

3.5.4 Fabrication MBFAEI Controller Unit

The PCB cards are assembled in the housing shown in Figure 3.56.

Figure 3.56: MBFAEIC Housing of the PCB Cards The incubator (MBFAEI) Controller in Operation (with Data logging) shown in Figure 3.57.

Figure 3.57: MBFAEI Controller in Operation (Data Logging)


96

3.5.5 Electrical Wiring

The Electrical Wiring of Egg turning motor, ventilation and humidity control

System shown in Figure 3.58.

Figure 3.58: Electrical Wiring of Egg turning motor, ventilation and humidity control System

GN

D

+12V

12V

12V

12V

Relay Contact(Control via MBFAEIC)

+88.8kRPM

EGG TRAY TURNINGDC GEAR MOTOR

HUMIDITY CONTROL

+88.8kRPM

VENTILATION FAN

+88.8kRPM

IR R

emote C

ontrol

Manual Sw

itch


97

The Electrical Wiring of four heating elements shown in Figure 3.59.

Figure 3.59: Electrical Wiring of Four Heating Elements

BOTTOM HEATER 1

BOTTOM HEATER 2

TOP HEATER 1

TOP HEATER 2

Nut

ral (

N)

Line

(230

V)

40W,230V

60W,230V

40W,230V

Relay Contact(Control via MBFAEIC)

Relay Contact ( Optional Temperature Security System)

60W,230V

Chapter 4 Test Hatching and Performance Analysis 4.1 Introduction

The pre-programmed microcontrollers were placed in the controller PCB. All

temperature and humidity sensors were also placed in their appropriate place in the

incubator and connect the controller. The heating elements, forced air fans, humidification

system, ventilation fan and egg turning system are installed and wiring from the controller.

Incubator Operation

Step 1: When Power of the Incubator is ON. Following welcome screen will appear:

Step 2: The Incubator will initialize itself and restore all previous Set values from

EEPROM and goes for normal operation and Run Mode.

Chapter 4. Test Hatching and Performance Analysis

The Incubators normal Run and Operation Mode Display information are

described in Figure 4.1.

Figure 4.1: The Incubators Normal Run and Operation Mode Display Information

By using menu buttons and user friendly Human Machine Interfacing Menu

Program (HMIMP) shown in Figure 3.45, and Figure 3.46 (Part 1 and Part 2) t

the clock and other incubation parameters are sets.

Duck and Hen Setter and Hatcher operations are inserted during system development.

simple and friendly operation,

Setter mode then the controller set all incubation parameters for Setter operation itself and

these incubation parameters can also set individually. Similarly,

Operation the incubator set for Duck and H

incubation parameters for Hatcher operation itself and these incubation parameters can

also set individually.



First Line:

Second Line:

Third Line:

Forth Line:

: The Incubators Normal Run and Operation Mode Display Information

buttons and user friendly Human Machine Interfacing Menu

Program (HMIMP) shown in Figure 3.45, and Figure 3.46 (Part 1 and Part 2) t

incubation parameters are sets. The data of incubation parameters of

d Hatcher operations are inserted during system development.

friendly operation, during Setter Operation the incubator set for Duck and Hen


these incubation parameters can also set individually. Similarly, during the

the incubator set for Duck and Hen Hatcher mode then the controller set all



: The Incubators Normal Run and Operation Mode Display Information

buttons and user friendly Human Machine Interfacing Menu

Program (HMIMP) shown in Figure 3.45, and Figure 3.46 (Part 1 and Part 2) the incubator

The data of incubation parameters of

d Hatcher operations are inserted during system development. For

the incubator set for Duck and Hen


during the Hatcher

controller set all



100

4.2 Incubation of Eggs in the Incubator (MBFAEI)

The first step was to keep the Incubator in a room indoor to protect incubator from

major weather changes or maintain the uniform temperature and humidity. The incubator

was placed in a stable environment, free of drafts and away from direct sunlight. The

temperature and humidity of the room housing the incubator should be controlled and

stable. Room temperature maintained between 24-27°C and humidity between 40-60% rH.

The incubators, water pan are filled with hot water and it runs without any eggs for

12 to 24 hours, for regulating and checking the internal temperature and humidity. The

incubator takes about 22 minutes to reach its Set Temperature (from 22 °C to 37.5 °C). At

that time it consumed 207 Watts. It consumes 69 Watts or Less than 69 Watts after

reaching its Set Temperature.

The second step was the collection and selection of the hatching eggs from

breeders, which were well developed, mature and healthy. Then the eggs were stored

before incubation.

Collection of Hatching Eggs:

Incubating eggs were collected at least 4 times a day. Well-shaped, standard-sized

eggs are selected for incubation. The eggs are cleaned and washed with a mild antiseptic

solution in hot water. Locally available household antiseptics such as Dettol or Savlon

used for this for fumigating hatching eggs, shown in Figure 4.2.

Figure 4.2: Fumigation of Hatching Eggs Egg Storage

Eggs are stored before incubation; the best Hatchability occurs when eggs are

stored for less than 7 days from the time they were laid. Storing eggs longer than 2 weeks

also can extend the normal incubation time as much as 1 day.


101

Fertile eggs are stored at temperature between 13ºC and 18ºC (Egg storage system

shown in Figure 4.3). For best hatchability, Storage temperature should never exceed 22ºC

and never go below 8ºC.

Figure 4.3: Egg Storage

The third step was Pre-incubation and loading of eggs in Setter tray. Pre-incubation:

To avoid temperature shock to the embryo and consequent condensation on the

shell, eggs are removed from the egg room and pre-warmed before setting the eggs. It is

recommended to gradually warm cooled eggs from storage up to the room and then

incubation temperatures at 99.5°F (37.5ºC), 55-60% RH (85-87°F wet-bulb thermometer)

[61]. Effective air circulation and correct room temperature are essential to achieve the

necessary even pre-warming of the eggs.

The eggs are pre-warmed by providing a good air circulation around the eggs to

reach 24 to 27 °C (at 50% RH), so that all can achieve the desired temperature for 4 hours

to 8 hours before setting in the incubator. They are also turned preferably every one to four

hours.

Loading of Eggs

Placing of eggs in the setter is called ‘Loading of eggs’ shown in Figure 4.4. The

eggs are set on setter when the temperature and humidity are correct and stable.

The fourth step was setter operations. Generally, the incubation period of

commercial chicks was 21 days. For test hatching, the set temperature and humidity for

chicken eggs was as 37.5ºC, 60%rH and egg turning every 1 hour until day 18 for chicken


102

eggs (until day 24 for duck eggs). The optimum physical conditions for any embryo to

grow successfully are correct temperature, correct humidity, adequate gas exchange and

regular turning of eggs.

Figure 4.4: Loading of Hatching Eggs to Setter Tray

Embryonic Development and Carefulness of Incubation: DAY 1

Stages of development:

Appearance of tissue development:

16 hours: First sign of resemblance to a chick embryo.

18 hours: Appearance of alimentary tract.

20 hours: Appearance of vertebral column.

21 hours: Beginning of formation of nervous system.

22 hours: Beginning of formation of head.

23 hours: Appearance of blood islands-vitelline circulation.

24 hours : Beginning of formation of eye.


103

Precaution / Remarks:

Allow the temperature in the incubator to rise to 36.5° C to 37.5° C.

Maintain the humidity in the incubation box at 55-65% rH.

DAY 2


• Tissue development very visible

• Appearance of blood vessels

25 hours: Beginning of formation of heart.

35 hours: Beginning of formation of ear.

DAY 3


Heart beats

Blood vessels very visible

50 hours: Beginning of formation of amnion.

60 hours: Beginning of formation of nasal structure.


104

DAY 4


Eye pigmented

DAY 5


Appearance of elbows and knees

DAY 6


• Appearance of beak

• Voluntary movements begins


105

DAY 7


• Comb growth begins

• Egg tooth begins to appear

Precaution / Remarks:

The eggs were candle on Day 7 and Day 14 to identify infertile and spoiled eggs.

The infertile and spoiled eggs were removed from the incubation chamber.

The fifth step, the eggs were candle at various stages of incubation to explore the size

of the air cell.

Candling: Candling is a process in which eggs are kept in front of a light source to find

out the defects in eggshell, embryonic development etc. An electric light bulb placed

inside a box with an egg-sized hole in the side. Each egg was place in turn into the hole

and the pattern of light shining through the shell observed.

Fertile egg : A faint pattern of blood vessels.

Infertile egg : These are transparent, with no sign of blood vessels.

Spoiled egg : These are opaque.

DAY 8


• Feather tracts seen

• Upper and lower beak equal in length


106

DAY 9


• Embryo starts to look bird-like

• Mouth opening appears

DAY 10


• Egg tooth prominent

• Toe nails

DAY 11


• Comb serrated

• Tail feathers apparent

DAY 12


• Appearance of elbows and knees


107

DAY 13


• Appearance of scales

• Body covered lightly with feathers

DAY 14


• Embryo turns head toward large end of egg

The sixth step, the eggs were again candle on Day 14 to identify infertile and

spoiled eggs. After 14 days, spoiled eggs need to be discarded.

DAY 15


• Gut is drawn into abdominal cavity.

DAY 16



108

• Feathers cover complete body

• Albumen nearly gone

DAY 17


• Amniotic fluid decreases

• Head is between legs

DAY 18


• Growth of embryo nearly complete

• Yolk sac is still on outside of embryo

• Head is under the right wing


109

The seventh step, was Hatcher Stage, the eggs were transfer to Hatcher.

Hatcher Stage:

On the 18th/19th day of incubation (considering the egg loading day is Day 0), the

hatching eggs are transferred from setter tray to Hatcher baskets when approximately 1%

of the eggs are slightly pipped shown in Figure 4.5. The optimum temperature set at

36.94°C (98.50º F) and relative humidity 65% rH for chicken egg during the Hatcher (last

3 days). The incubator set for 36.9°C and relative humidity 65% rH during the Hatching.

To increase humidity in the incubator the water surface area was increased.

Figure 4.5: Eggs are Transferred to Hatcher Tray DAY 19


• Yolk sac draws into the body cavity

• Amniotic fluid gone

• Embryo occupies most of the space within the egg (not in the air cell)

Precaution /Remarks:

Stop turning the eggs.

Cracks are seen on the chicken eggshells.

Once a day, gently moisten the eggs using a wet cotton cloth to soften the shell and

help the chicks emerge.


110

DAY 20 and DAY 21


• Yolk sac drawn completely into body

• Embryo becomes a chick (breathing in air in cell)

• Internal and external pip Precaution /Remarks:

Chicks start to come out from the eggs.

Most of the chicks have hatched as shown in Figure 4.6.

Figure 4.6: Successfully Hatched DOCs (Day Old Chicks)

The last step is pulling the hatch, hatchery waste disposal, washing and cleaning

the incubator.

Pulling the Hatch

The process of removing the chicks from the hatcher is often called pulling the

hatch. Chicks are removed from the hatcher as soon as all are hatched and about 95% are

dry. Chicks are held in a room where a temperature of 24°C or more and a relative

humidity of 50% have to be ensured.


111

Steps involved in Successful Egg Incubation Operations shown in Figure 4.7.

Figure 4.7: Steps Involved in Successful Egg Incubation Operations


112

4.3 The Incubator (MBFAEI) Hatching Tests and Performance Analysis

Figure 4.8: The Incubator (MBFAEI) Hatched Chicks-1

Figure 4.9: The incubator (MBFAEI) Hatched Ducks


113

Figure 4.10: The Incubator (MBFAEI) Hatched Chicks-2

Figure 4.11: The Incubator (MBFAEI) Hatched (Multistage) Coturnix Quail


114

Figure 4.12: The Incubator (MBFAEI) Hatched (Multistage) Chicks

Figure 4.13: Coturnix Quail and Indigenous Chicks Intensive Rearing


115

The Incubator (MBFAEI) hatching tests were carried out step by step five times.

Depending on the test results the incubator was modified several times and advanced

features are added. The implemented incubator was tested for Hen, Quail and Duck eggs

for single and multistage egg incubation (different types of eggs, of different embryonic

ages).

Figure 4.14: Implemented Incubators

The incubator takes about 22 minutes to reach its Set Temperature (from 22°C to

37.5°C). At that time it consumes 207 Watts. It consumes 69 Watts or less after reaching

its Set Temperature. It consumes approximately 35 kWh (kilowatt-hour) electric powers

for chick (21 days) incubation.

The designed and implemented egg incubators during this project work are shown

in Figure 4.14. The Incubators were developed to serve a dual purpose (i.e. the

combination of Setter and Hatcher in a single unit), unlike the imported type which has a

separate Hatcher and Setter. This Incubator can therefore be adopted by small scale

poultry farmers. The Incubator may use for egg embryo research and laboratory works.

The advanced data logging facility will help to get a right prediction from output data.

Chapter 5 Conclusion and Recommendation 5.1 Conclusion

In this project, microcontroller based forced air egg incubator is designed,

implemented and tested. This project uses microcontroller to control the parameters of

incubator for stable and accurate egg incubation process. The control unit is based on a

PIC microcontroller. It is built for monitoring (room temperature), control (incubator

temperature, egg turning, ventilation and humidity) and displaying different parameters

i.e. temperature, humidity, time, date, set temperature and incubation day etc. User-

friendly Human Machine Interfacing Menu Program (HMIMP) is implemented which

allows the user to visualize different parameters during setting system configuration. The

advanced auto saving data log in excel is very useful and realistic for getting right

prediction from output result to improve incubator operation for optimum performance.

The implemented incubator is tested for Duck, hen and Quail eggs.

On first test Hatching, many clear eggs show no development due to infertile eggs,

One blood ring and dead embryo at an early stage found and late death (17th day)

occurred due egg turning system breakdown problem.

On second test Hatching, the incubator successfully hatches chicken eggs, the

infertile clear egg problem reduced by using selected eggs and Hatching start on 21th

days, only two paralyzed chicks and one piped eggs without hatching problem occurred

due to improper temperature and humidity during load shedding.

Chapter 5. Conclusion and Recommendation

117

Depending on second test hatching the incubator is modified for third Hatching,

the incubator successfully hatches duck eggs, hatching start on 2127 days. During hatching

eggs are collected from local farmer most of eggs laid in dirty place and covered by

contaminating microorganisms from the feces or feather material of the parents, some eggs

are unhatched because of infection caused by a bacterium that enters through the porous

egg shell and kills some embryo’s and newly hatched chicks but other ducks are still alive

and going on full egg production.

For Fourth test hatching, the incubator casing was reconstructed and the insulation

layers are increased to reduce the heat loss, IPS was connected for continuous power

supply. Eggs are collected from own parent breeders. In this test hatching, all chicken eggs

are successfully hatched in good condition; the chicks were healthy and standard size.

Hatching started on the 20th day, and most of the chicks hatch within 4-5 hours, 100%

hatchability found during this hatching.

Multistage incubation tested on Fifth test hatching containing different eggs (Quail,

Hen and Duck) of different embryonic ages. Hen and Quail eggs are collected from own

parent breeders and duck eggs were collected from local farmers. Quail hatching starts on

the 16th day, and the entire Quail baby hatched within 2-3 hours. 100% hatchability found

during multistage Quail hatching. Chick hatching started on 20th day and the entire chick

hatched within 4-5 hours. 100% hatchability found during multistage chick hatching. Duck

hatching started on 27th day and some eggs were successfully hatched but some eggs were

unhatched because of infertility and infection. The Quail and Chicks are put in same

brooder and due to intensive rearing they are in good condition; due to lack of sufficient

brooder and proper knowledge of duck rearing, baby ducks cannot rearing properly.

During test hatching it is found that when continuous power supply used then

incubation period slightly decrease, chicks were healthy and good size and 100%

hatchability found, also when eggs are collected from own parent breeders than there is no

infection and infertility problems.

Chapter 5. Conclusion and Recommendation

118

5.2 Recommendations

This designed incubator model could be one of the cheapest with a manageable

capacity of eggs, beneficial to small scale to large scale poultry farmers and research

laboratory. The incubator can be modified to run on solar or wind power since the power

requirement of the incubator after reaching its set temperature is quite low (69 Watts or

less than 69 Watts), which may be helpful for the rural breeders, where there is a frequent

power cut or no electrical power supply. In future, this project can be modified by using a

PID controller with overshoot as low as possible using higher-end microcontroller to

control temperature also improve the turning system.

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[43] D. C. Deeming, “Characteristics of unturned eggs: critical period, retarded embryonic growth and poor albumen utilization,” Poultry Science, Vol. 30, pp. 239-249, 1989a.

[44] H. R. Wilson and R. F. Wilmering, “Hatchability as affected by egg turning in high density plastic egg flats during the last half of incubation,” Poultry Science, Vol. 67, pp. 685-688, 1988.

[45] A. H. Lourens, Van den brand, R. Meijerhot and B. Kemp, “Effect of eggshell temperature during incubation on embryo development, hatchability and post hatch development,” Poultry Science, Vol. 84, pp. 914-920, 2005.

[46] M Meir and A Ar, “Increasing hatchability of turkey eggs by matching incubator humidity to shell conductance of individual eggs,” Poultry Science, Vol. 63, pp. 1489-1496, 1984.

[47] F. G. Burton and Tullet, “The effect of egg weight and shell porosity on the growth and water balance of the chicken embryo,” Comparative Biochemistry and Physiology-Part A, Vol. 75, pp. 167-174, S.G.,1985.

References

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[48] D. M. Bird and Laque, “Fertility, egg weight loss, hatchability, and fledgling success in replacement clutches of captive American Kestrels,” Canadian Journal of Zoology , Vol. 60, pp. 80-88, P. C. 1980.

[49] P. D. Olsen and Olsen, “Egg weight loss during incubation in captive Australian Kestrels Falco cenhroides and Brown Goshawks Accipiter fasciatus,” Emu, Vol. 87, pp. 196-199, 1987.

[50] C. A. Weinheimer and J. R Spotila, “Shell resistance and evaporative water loss from bird eggs: Effects of wind speed and egg size,” American Zoologist, Vol. 18, p. 636, 1978.

[51] PIC16F87X Data Sheet - Microchip, ww1.microchip.com/downloads/en/DeviceDoc / 30292c .pdf

[52] LM35 datasheet, http://www.ti.com/ general/docs/lit/getliterature.tsp? generic PartNumber= lm35 &fileType=pdf

[53] DS18B20 datasheet , http://datasheets.maximintegrated.com/en/ds/DS18B20.pdf

[54] HSM-20G datasheet, http://www.seeedstudio.com/ depot/ datasheet/ HSM-20G.pdf

[55] DS1302 datasheet, http://datasheets. maximintegrated.com /en/ds /DS1302.pdf

[56] www.microchip.com

[57] www.melabs.com

[58] http://PBP3.com.

[59] www.mecanique.co.uk

[60] http://pbp3.com/downloads/PBP_Reference_Manual.pdf

[61] R. Haigh, “The breeding and artificial incubation of hawks, buzzards and falcons Accipiter,” International Zoo Year book, Vol. 23, pp. 51-58, 1984.

Appendix A: Firmware Development for MBFAEI

'******************************************************************************************** '* Name : Design and Implementation of a Microcontroller Based Forced Air Egg Incubator * '* * '* Author : * '* Muhammad Anowar Kabir (MIEB-26234), [email protected] * '* Master of Engineering in Electrical and Electronic Engineering,DUET * '* Supervisor: Prof. Dr. Md. Anwarul Abedin, * '* Head, EEE Department, DUET,Gazipur * '* Notice : Sample Code * * Version : * '* Notes : 01818713364 * '* : * '* Date : 7/20/2014,, * '******************************************************************************************** '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' ''''''''''''''''''''''''''''CONFIGERATION''''''''''''''''''''''''''''''''''''''' #CONFIG __CONFIG _CP_OFF & _WDT_ON & _BODEN_ON & _PWRTE_ON & _HS_OSC & _WRT_OFF & _LVP_OFF & _CPD_OFF #ENDCONFIG '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' DEFINE OSC 8 '''''''''''''''''''''''''''''CONFIGERATION'''''''''''''''''''''''''''''''''''''' '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' '''''''''''''''''''''''''''''''''PORT SETUP''''''''''''''''''''''''''''''''''''' TRISA=%111111 TRISB=%00000001 TRISC=%00000000 TRISD=%11100000 TRISE=%00000000 PORTA=0 PORTB=0 PORTC=0 PORTD=0 PORTE=0 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' '''''''''''''''''''''''''''''''''PORT SETUP''''''''''''''''''''''''''''''''''''' 'LCD PORT SETUP DEFINE LCD_DREG PORTB DEFINE LCD_DBIT 4 DEFINE LCD_RSREG PORTB DEFINE LCD_RSBIT 2 DEFINE LCD_EREG PORTB DEFINE LCD_EBIT 3 DEFINE LCD_BITS 4 DEFINE LCD_LINES 4 symbol BUTTOM_HEATER_1 =PORTD.0 symbol BUTTOM_HEATER_2 =PORTD.1 symbol TOP_HEATER_1 =PORTD.2 symbol TOP_HEATER_2 =PORTD.3 SYMBOL BUZER =PORTD.4 MENU_BUTTON VAR PORTD.5 UP_BUTTON VAR PORTD.6 DOWN_BUTTON VAR PORTD.7 SYMBOL EGG_TURNING_MOTOR =PORTC.0 symbol HUMIDIFIER_FAN =PORTC.1 symbol VENTILATION_MOTOR =PORTC.2 RTC_CLK var PORTE.0 RTC_DTA var PORTE.1 RTC_RST var PORTE.2


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m var byte n var byte 'VERIABLE USED FOR RTC SEC VAR BYTE MINITE VAR BYTE HOUR VAR BYTE INCUBATION_DAY VAR BYTE DATE VAR BYTE MONTH var byte YEAR var byte DAY VAR BYTE BOX var byte 'VERIABLE USED FOR RTC NUMBER VAR BYTE ONETH VAR BYTE TENTH VAR BYTE ADCON1 = %10000010 'AE0-AE2 =Digital ,AN0-AN5=Analog Define ADC_BITS 10 Define ADC_CLOCK 3 Define ADC_SAMPLEUS 50 adchsm var word 'word is 16 bit , 65535 hsm var word HUM_abc var word HUM_ab var word HUM_cd var word hum_d_ab var word adclm35_1 var word lm35_1 var word adchsm2 var word hsm2 var word HUMIDITY VAR BYTE HUM VAR BYTE TSET VAR BYTE T_SET VAR BYTE TSET_T VAR word ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' SYMBOL DS18_COMM_PIN_DQ_TOP=PORTB.1 DS18_TEMP_IN_CELCIUS VAR WORD Float VAR WORD PLUS_MINUS_SIGN VAR BYTE Busy VAR BIT RAW_TEMP VAR WORD NEGATIVE_TEST_BIT VAR RAW_TEMP.Bit11 NEGATIVE_TEMP CON 1 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' SYMBOL DS18_COMM_PIN_DQ_BUTTOM=PORTC.4 DS18_TEMP_IN_CELCIUS1 VAR WORD Float1 VAR WORD Busy1 VAR BIT PLUS_MINUS_SIGN1 VAR BYTE RAW_TEMP1 VAR WORD NEGATIVE_TEST_BIT1 VAR RAW_TEMP1.Bit11 NEGATIVE_TEMP1 CON 1 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' SET VAR BYTE AIR VAR BIT MOTOR_C VAR BIT EGG_TURNING_TYPE VAR BYTE SEC_STOP VAR BYTE MENU_NO VAR BYTE


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CREADITE_GOES_TO: LCDOUT $FE,$84,"Ok." 'LCDOUT $FE,$80,"Automatic Incubator" 'lcdout $FE,$C0," M A Kabir" 'LCDOUT $FE,$94," MEng.-102211" 'lcdout $FE,$D4," DR. A ABDIN,DUET" PAUSE 1000 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' START: MENU_NO=0 SET=1 READ $01,TSET:IF TSET=255 THEN TSET=0 READ $02,HUMIDITY:IF HUMIDITY=255 THEN HUMIDITY=0 READ $09,SEC_STOP:IF SEC_STOP=255 THEN SEC_STOP=0 READ $07,INCUBATION_DAY:IF INCUBATION_DAY=255 THEN INCUBATION_DAY=0 READ $10,EGG_TURNING_TYPE:IF EGG_TURNING_TYPE=255 THEN EGG_TURNING_TYPE=0 READ $11,T_SET:IF T_SET=255 THEN T_SET=1 READ $06,MOTOR_C AIR=1 READ $04,m:IF m=255 THEN m=0 READ $05,n:IF n=255 THEN n=0 Pause 2 gosub RTC_SENSOR_READ Pause 2 GOSUB TEMP_SENSOR_DS18_READ Pause 10 GOSUB TEMP_SENSOR_DS18_READ1 Pause 1000 LCDOUT $FE,1 'Clear screen. Pause 10 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' 'MAIN PROGRAM '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' MAIN: GOSUB HSM_20G_HUM GOSUB HSM_20G_HUM2 gosub read_LM35_1 Pause 1 GOSUB TEMP_SENSOR_DS18_READ Pause 1 GOSUB TEMP_SENSOR_DS18_READ1 Pause 1 GOSUB RTC_SENSOR_READ Pause 1 GOSUB DAY_OF_WEEK GOSUB DISPLAY GOSUB ROOM_HEATING_CONTROL GOSUB HUMIDITY_CONTROL Pause 3 GOSUB DATA_LOGGER IF MOTOR_C=1 THEN GOSUB EGG_TURNING_MOTOR_CONTROL ENDIF IF MENU_BUTTON=1 THEN GOTO MENU_CHANGE goto MAIN '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' 'MAIN PROGRAM ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''


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'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' 'DS18B20 Temperature sensor read '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' TEMP_SENSOR_DS18_READ: OWOUT DS18_COMM_PIN_DQ_TOP, 1, [$CC, $44] WAIT_H: OWIN DS18_COMM_PIN_DQ_TOP, 4, [Busy] ' IF Busy = 0 THEN WAIT_H OWOUT DS18_COMM_PIN_DQ_TOP, 1, [$CC, $BE] OWIN DS18_COMM_PIN_DQ_TOP, 2, [RAW_TEMP.Lowbyte, RAW_TEMP.Highbyte] GOSUB DS18_DATA_TO_CELCIUS_CAL RETURN DS18_DATA_TO_CELCIUS_CAL: PLUS_MINUS_SIGN = "+" IF NEGATIVE_TEST_BIT = NEGATIVE_TEMP THEN PLUS_MINUS_SIGN = "-" RAW_TEMP=~RAW_TEMP+2 endif float = (RAW_TEMP*10)/16 DS18_TEMP_IN_CELCIUS=FLOAT/10 IF MENU_BUTTON=1 THEN GOTO MENU_CHANGE RETURN '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' ‘’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’’ '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' 'Temperature Control Sub-program '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' ROOM_HEATING_CONTROL: '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' TSET_T =TSET*10+T_SET if FLOAT>TSET_T then LOW TOP_HEATER_2 ENDIF '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' if FLOAT=<TSET_T-m then high TOP_HEATER_1 ENDIF if FLOAT=<TSET_T-n then high TOP_HEATER_2 ENDIF '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' if float1>TSET_T then LOW BUTTOM_HEATER_1 LOW BUTTOM_HEATER_2 ENDIF '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' if float1=<TSET_T-m then high BUTTOM_HEATER_1 ENDIF if float1=<TSET_T-n then high BUTTOM_HEATER_2 ENDIF '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' if FLOAT=>TSET_T+2 OR float1=>TSET_T+2 OR HUMIDITY+5<hum_d_ab then HIGH VENTILATION_MOTOR GOSUB BIPBIP ELSE LOW VENTILATION_MOTOR '


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ENDIF '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' if FLOAT<TSET_T-30 OR float1<TSET_T-30 OR HUMIDITY-5>hum_d_ab then GOSUB BIP ENDIF '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' IF MENU_BUTTON=1 THEN GOTO MENU_CHANGE RETURN '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' 'Display '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' DISPLAY: lcdout $FE,$80,"T1=",DEC DS18_TEMP_IN_CELCIUS1,".",DEC1 (FLOAT1),"'C, T2=",DEC DS18_TEMP_IN_CELCIUS,".",DEC1 (FLOAT),"'C" lcdout $FE,$C0,"H=",DEC hum_d_ab,"%rH, Set=",DEC2 TSET,".",DEC1 T_SET,"'C" LCDOUT $FE,$94,"R=",DEC lm35_1/100,".",DEC1 lm35_1,"C,",DEC hsm2,"%rH",",Day=",DEC2 INCUBATION_DAY LCDOUT $FE,$D4,DEC2 HOUR,":",DEC2 MINITE,":",DEC2 SEC,"<",DEC2 DATE,"/",DEC2 MONTH,"/",DEC2 YEAR IF SEC=>SEC_STOP THEN LOW EGG_TURNING_MOTOR IF HOUR=6 AND MINITE=6 AND SEC=6 THEN INCUBATION_DAY=INCUBATION_DAY+1 IF INCUBATION_DAY=31 THEN INCUBATION_DAY=0 WRITE $07,INCUBATION_DAY ENDIF IF SEC>60 THEN GOSUB bip SEC=0 GOSUB TIMESET Pause 4 SEC=0 GOSUB TIMESET GOTO START ENDIF RETURN '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' 'DS1302 Real Time Clock(RTC) Read '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' RTC_SENSOR_READ: high RTC_RST OUTPUT RTC_DTA shiftout RTC_DTA, RTC_CLK, 0, [$BF] INPUT RTC_DTA SHIFTIN RTC_DTA, RTC_CLK, 1, [SEC, MINITE, HOUR,DATE , MONTH, DAY, YEAR, BOX] BOX=SEC :GOSUB BCDTODEC :SEC=NUMBER BOX=MINITE :GOSUB BCDTODEC :MINITE=NUMBER BOX=HOUR :GOSUB BCDTODEC :HOUR=NUMBER BOX=DATE :GOSUB BCDTODEC :DATE=NUMBER BOX=MONTH :GOSUB BCDTODEC :MONTH=NUMBER BOX=YEAR :GOSUB BCDTODEC :YEAR=NUMBER BOX=DAY :GOSUB BCDTODEC :DAY=NUMBER low RTC_RST return BCDTODEC: ONETH=BOX & %01110000 ONETH=ONETH>>4 TENTH=BOX & %00001111 NUMBER=ONETH*10+TENTH return DAY_OF_WEEK: SELECT CASE DAY


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CASE 1 LCDOUT $FE,$E5,">Su" CASE 2 LCDOUT $FE,$E5,">Mo" CASE 3 LCDOUT $FE,$E5,">Tu" CASE 4 LCDOUT $FE,$E5,">We" CASE 5 LCDOUT $FE,$E5,">Th" CASE 6 LCDOUT $FE,$E5,">Fr" CASE 7 LCDOUT $FE,$E5,">Sa" END SELECT RETURN ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' MENU_NAMEs: SELECT CASE MENU_NO CASE 0 lcdout $fe,$80,"Pres MENU/UP/Dn" 'LCDOUT $FE,$C0," " 'lcdout $fe,$80,"MENU PROGM.IN/OUT" 'lcdout $fe,$c0,"Press BUTTON " 'LCDOUT $FE,$94,"MENU >to Set " 'LCDOUT $FE,$D4,"UP/DOWN>next Menu" 'LCDOUT $FE,$D4,"Press MENU/UP/Down" IF MENU_BUTTON=1 THEN END_MENU_SET CASE 1 ' ' lcdout $fe,$80,"Hen & Duck Eggs" LCDOUT $FE,$c0," Setter mode" IF MENU_BUTTON=1 then GOSUB BIP TSET =37:T_SET=5:m=2:n=5:HUMIDITY= 60:MOTOR_C=1:SEC_STOP=1:EGG_TURNING_TYPE=1 'SEC_STOP=1 Depends on Gear System WRITE $01,TSET:PAUSE 2 WRITE $11,T_SET:PAUSE 2 WRITE $02,HUMIDITY:PAUSE 2 WRITE $06,MOTOR_C:PAUSE 2 WRITE $10,EGG_TURNING_TYPE :PAUSE 2 WRITE $09,SEC_STOP:PAUSE 2 WRITE $04,m:PAUSE 2 WRITE $05,n:PAUSE 2 WHILE MENU_BUTTON=1:WEND GOTO MENU_CHANGE ENDIF CASE 2 ' lcdout $fe,$80,"Hen & Duck Eggs" LCDOUT $FE,$c0," Hatcher mode" IF MENU_BUTTON=1 then GOSUB BIP TSET =36:T_SET=8:HUMIDITY= 70:MOTOR_C=0:SEC_STOP=0:EGG_TURNING_TYPE=0:m=2:n=5 WRITE $01,TSET:PAUSE 2 WRITE $11,T_SET:PAUSE 2 WRITE $02,HUMIDITY:PAUSE 2 WRITE $06,MOTOR_C:PAUSE 2 WRITE $09,SEC_STOP:PAUSE 2 WRITE $10,EGG_TURNING_TYPE :PAUSE 2 WRITE $04,m:PAUSE 2 WRITE $05,n:PAUSE 2 WHILE MENU_BUTTON=1:WEND GOTO MENU_CHANGE ENDIF CASE 3 ' lcdout $fe,$80,"HUMIDITY SETING" LCDOUT $FE,$c0," " IF MENU_BUTTON=1 then WHILE MENU_BUTTON=1:WEND GOSUB BIP GOTO HUMIDITY_SETTING ENDIF


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CASE 4 lcdout $fe,$80,"TEMPERATURE SET" LCDOUT $FE,$C0," " IF MENU_BUTTON=1 then WHILE MENU_BUTTON=1:WEND GOSUB BIP GOTO TEMP_SETTINGS ENDIF CASE 5 ' lcdout $fe,$80,"EGGTRAY TURNING" LCDOUT $FE,$c0,"MOTOR SETTINGS" IF MENU_BUTTON=1 then WHILE MENU_BUTTON=1:WEND GOSUB BIP GOTO MOT_SET ENDIF CASE 6 ' lcdout $fe,$80," TIME-DATE-DAY " LCDOUT $FE,$c0," SETTINGS " IF MENU_BUTTON=1 then GOSUB BIP WHILE MENU_BUTTON=1:WEND GOTO TIME_DATE_DAY_SETTINGS ENDIF CASE 7 ' lcdout $fe,$80,"EGG TRAY MOTOR " lcdout $fe,$c0,"MANUEL RUN " IF MENU_BUTTON=1 theN GOSUB BIP WHILE MENU_BUTTON=1:WEND GOTO MANUEL ENDIF CASE 8 ' lcdout $fe,$80,"INCUBATION DAY " LCDOUT $FE,$c0," SETTING " IF MENU_BUTTON=1 then GOSUB BIP WHILE MENU_BUTTON=1:WEND GOTO DAY_SETTINGS ENDIF END SELECT RETURN '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' 'Egg Tray Turning Motor Manual Operation(Run) ‘ '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' MANUEL: GOSUB LCD_CLEAR MANU: LCDOUT $FE,$80," PRESS <UP>" lcdout $fe,$C0,"TO RUN MOTOR " IF MENU_BUTTON=1 then GOTO MENU_CHANGE ENDIF IF UP_BUTTON=1 THEN lcdout $fe,$D4,"MOTOR RUNNING" GOSUB BIP HIGH EGG_TURNING_MOTOR ELSE lcdout $fe,$D4,"MOTOR OFF " LOW EGG_TURNING_MOTOR ENDIF GOTO MANU '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' 'Incubation Day setting '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' DAY_SETTINGS: WHILE MENU_BUTTON=1:WEND


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GOSUB LCD_CLEAR READ $07,INCUBATION_DAY INCUBATION_DAY_SET: LCDOUT $FE,$80,"INCUBATION DAY SET:" lcdout $FE,$C0,"DAY=",DEC2 INCUBATION_DAY IF MENU_BUTTON=1 THEN WRITE $07,INCUBATION_DAY:PAUSE 2 GOTO MENU_CHANGE ENDIF IF UP_BUTTON=1 THEN INCUBATION_DAY=INCUBATION_DAY+1 IF INCUBATION_DAY=31 THEN INCUBATION_DAY=0 WHILE UP_BUTTON=1:WEND ENDIF IF DOWN_BUTTON=1 THEN INCUBATION_DAY=INCUBATION_DAY-1 IF INCUBATION_DAY>31 THEN INCUBATION_DAY=30 WHILE DOWN_BUTTON=1:WEND ENDIF GOTO INCUBATION_DAY_SET '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' END

Appendix B: Firmware Development for IR Remote Control based Egg Turning System

'**************************************************************** '* Name : IR Remote Control for Egg Turning System (IR Receiver) '**************************************************************** @ Device PIC12F675,WDT_ON,PWRT_ON,PROTECT_OFF,MCLR_OFF,BOD_OFF ANSEL=0 'ADC off CMCON=7 'analog comparators off DEFINE OSCCAL_1K 1 'Internal Clock Auto-Cal 'The PULSIN resolution is 10uS with PIC running at 4MHz Pulse var byte[12] Start var byte Command var byte Device var byte Counter var byte WaitForStart: 'Wait for Start signal PuLSIN GPIO.3,0,start 'Check the low pulse width if start < 180 then WaitForStart 'If the Start pulse < 1.8mS repeat the loop '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' for counter=0 to 11 'Get the 12 pulses of the signal pulsin GPIO.3,0,pulse[counter] next StoreBits: command=0 device=0 for counter=0 to 6 if pulse[counter] < 90 then 'Determine if the pulse represents 0 or 1 command.0[counter] = 0 Else command.0[counter] = 1 endif next for counter=7 to 11 if pulse[counter] < 90 then device.0[counter-7] = 0 Else device.0[counter-7] = 1 endif next select case command case 0

high GPIO.1=1 ; Egg Turning Motor On case 1

high GPIO.1=0 ;Egg Turning Motor OFF case 2

high GPIO.1=1 ;Egg Turning Motor ON and OFF pause 100 high GPIO.1=0 end select pause 100 goto WaitForStart end

Design and Implementation of a Microcontroller Based Forced Air Egg Incubator · 2020-02-03 ·...

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