Soil Moisture Based Automatic Plant Irrigation Sytem

Measurement

Introduction:

This project Microcontroller Based Soil Moisture Measurement is useful in

analyzing the moisture level present in any particular land plot. This tool is a low cost

solution for moisture measurement which is of utmost importance in the agricultural

sector. The circuit is capable of generating an alarm if the moisture level of the soil under

consideration goes low. The circuit also provides relay interface which can be used to

apply any automatic and immediate control action in case the moisture in the soil is less.

For example, if the moisture is low in a grape field, then a solenoid valve switched by a

relay can be opened, which would turn ON all the drips of the region under consideration.

Block Diagram

The circuit hardware consists of a general purpose microcontroller to measure and

compare the moisture levels with a preset threshold value. The soil moisture sensor is a

simple conductivity sensor connected to the microcontroller through an ADC which

converts the analog value of the sensor to a digital value. This digital value is then

compared with the preset threshold value and an appropriate control action is taken.

The circuit is equipped with a keypad for the user to enter or preset a threshold

value on which the system is supposed to take a control action. The circuit also has an

LCD display which displays the current moisture level and the current state of control

action.

Soil Moisture Sensor probe:

Soil moisture sensors measure the water content in soil. A soil moisture probe is made up

of multiple soil moisture sensors. One common type of soil moisture sensors in

commercial use is a Frequency domain sensor such as a capacitance sensor. Another

sensor, the neutron moisture gauge, utilize the moderator properties of water for neutrons.

In This sensor We are using 2 Probes to be dipped into the Soil

As per Moisture We will get Analog Output variations from 0.60volts - 12volts

Input Voltage 12 VDC

For many applications soil moisture measurement devices like time domain reflect

meters are too expensive and offer more features than really needed. Therefore a

prototype for a simple and economical soil moisture probe has been developed, which

allows measuring the mean moisture. Another important state variable besides moisture is

temperature.

MICRO-CONTROLLER Used:

This is the most important segment of the project, i.e. the microcontroller 8052. The

controller is responsible for detection and polling of the peripherals status. It is

responsible for making. It is responsible for prioritizing all the devices attached to it.

WE have used the ATMEL 89s51 microcontroller. The AT89S51 is a low-power, high-

performance CMOS 4-bit microcontroller with 8K bytes of in-system programmable

Flash memory. It has got 32 I/O lines, Watchdog timer, two data pointers, two 16-bit

timer/counters, six-vector two-level interrupt architecture, a full duplex serial port, on-

chip oscillator, and a clock circuitry.

FEATURES OF 89V51:

8 bit CPU for control application.

64 KB flash memory

1 KB RAM

32 I/O lines

LCD Display:

It will display the time, date as well as current room temperature. Output of

microcontroller is applied to the LCD display.

Software Used

1) keil IDE for ARM

2) Flash magic For ARM

Advantages:

1) Water Supply can be adjusted as per moisture level in soil.

2) Moisture readings & effect can be useful for research in agriculture

3) Better use of water will help to save water also improve fertility of soil.

Applications:

1) It can be used for many crops to manage water supply.

2) Soil moisture can be measured & monitored.

3) It can be used in regions where water problem exists to improve efficient use of

water

Future Scope:

1) Soil PH can be measured to test the soil.

2) Soil parameters like nitrogen, potassium can be measured for soil analysis.

3) Data collection can be done for research purpose.