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ME- 362ME- 362Instrumentation and Measurement SessionalInstrumentation and Measurement Sessional

A brief look into “ A brief look into “ THORTHOR ” ” or the “ or the “ TTerrain errain HHazard azard OOptimized ptimized RRobot”obot”

Presented by Group A Presented by Group A 1515

Roll NoRoll No Student NameStudent Name 0510005 Naser Imran Hossain 0510005 Naser Imran Hossain ** 05100140510014 Md. Rokanuzzaman Khan Md. Rokanuzzaman Khan 0510024 Prajnaprasun 0510024 Prajnaprasun Bhattacharjee Bhattacharjee 0510033 Nahid Pervez0510033 Nahid Pervez

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Presentation OverviewPresentation Overview

IntroductionIntroductionObjectives & FeaturesObjectives & FeaturesMechanical orientationMechanical orientationCircuitry Circuitry PurposePurposeCritiqueCritiqueOptimization & Future plansOptimization & Future plansConclusionConclusionAcknowledgmentsAcknowledgments

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IntroductionIntroduction

Since Karel Capek (1890-1938) first used the word Since Karel Capek (1890-1938) first used the word ‘robot’, man has been infatuated with the creation of ‘robot’, man has been infatuated with the creation of mechanized companions.mechanized companions.

Our project was named after the Norse god Of thunder Our project was named after the Norse god Of thunder who use to banish evil to their demise. For it too might who use to banish evil to their demise. For it too might one day help humanity in its struggle against the evils of one day help humanity in its struggle against the evils of pollution and contamination.pollution and contamination.

Our inspiration was the brave remote neutralization of a Our inspiration was the brave remote neutralization of a possible catastrophe by one of our hon’ teachers when a possible catastrophe by one of our hon’ teachers when a jammed Co-60 source of the jammed Co-60 source of the γγ--beam irradiator at beam irradiator at Bangladesh Institute of Nuclear Agriculture (BINA) Bangladesh Institute of Nuclear Agriculture (BINA) threatened the lives of many in the late 80’s.threatened the lives of many in the late 80’s.

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AttendeesAttendees

The Project - “ The Project - “ THORTHOR ” ”

The teamThe team

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ObjectivesObjectives

Manually maneuver into hazardous environment.Manually maneuver into hazardous environment.

Avoid obstacles and detours on the way using Avoid obstacles and detours on the way using fast directional control.fast directional control.

Grip mission objectives with link-driven gripperGrip mission objectives with link-driven gripper

Bring objective back into safe containment area Bring objective back into safe containment area and deposit.and deposit.

Sense heightened level of temperature or lack of Sense heightened level of temperature or lack of light on due process and indicate.light on due process and indicate.

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FeaturesFeatures

Custom designed “ Gripper Arm ”Custom designed “ Gripper Arm ”

Multidirectional “Pseudo Holonomic” Control.Multidirectional “Pseudo Holonomic” Control.

Smart ‘ Ambient ’ light and heat sensing.Smart ‘ Ambient ’ light and heat sensing.

High torque driving mechanism for heavy High torque driving mechanism for heavy payloads.payloads.

Minor object avoidance. Minor object avoidance.

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Mechanical OrientationMechanical Orientation

Acrylic made to reduce weight.Acrylic made to reduce weight.

Wire manipulated.Wire manipulated.

Maximum jaw clearance 8mm.Maximum jaw clearance 8mm.

Spring operated auto recoiling.Spring operated auto recoiling.

Designed to always assume a Designed to always assume a vertical position during operation.vertical position during operation.

Gripping control by gear-motor.Gripping control by gear-motor.

Gripper Arm

Part 1: The “ Grip ”

Fig : The Grip

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Mechanical Orientation (cont)Mechanical Orientation (cont)

Consists of 4 acrylic links in totalConsists of 4 acrylic links in total

Supports the vertical positioning Supports the vertical positioning of the grip/claw.of the grip/claw.

Counter supports each other in Counter supports each other in cases of heavier payloads.cases of heavier payloads.

Arm leverage and height Arm leverage and height controlled by wires and a gear controlled by wires and a gear motor.motor.

Part 2: The “Part 2: The “ArmArm””

Fig: The Arm

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Mechanical Orientation (cont)Mechanical Orientation (cont)

Separate gear motors control Separate gear motors control individual wheels, crane individual wheels, crane fulcrum and gripper.fulcrum and gripper.

Polarity is changed Polarity is changed instantaneously with DPDT instantaneously with DPDT switches.switches.

Navigation StrategyNavigation StrategyPart 1: HardwarePart 1: Hardware

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Mechanical Orientation (cont)Mechanical Orientation (cont)

Both wheel rotate in Both wheel rotate in common directions to go common directions to go forward or backward.forward or backward.

To ensure Pseudo-To ensure Pseudo-Holonomic movement, Holonomic movement, motors are coupled to the motors are coupled to the forward wheels only.forward wheels only.

Part 2 : MechanicsPart 2 : Mechanics

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Mechanical Orientation (cont)Mechanical Orientation (cont)

RW rotates opposite to LW to change direction RW rotates opposite to LW to change direction and vice versa.and vice versa.

Smooth turns are made possible by stopping Smooth turns are made possible by stopping one of the wheels and resuming the otherone of the wheels and resuming the other

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Circuitry Circuitry

Part 1: Overview & FunctionsPart 1: Overview & Functions

LDR senses lack of light and indicates with a Green LED.LDR senses lack of light and indicates with a Green LED.

NTC-Type thermistor senses increase in temperature and NTC-Type thermistor senses increase in temperature and indicates with a Red LEDindicates with a Red LED

Possible to calibrate sensors according to ambient variables.Possible to calibrate sensors according to ambient variables.

In circuit “ Operational Amplifier ” ( LM-324 ) synchronizes In circuit “ Operational Amplifier ” ( LM-324 ) synchronizes between sensor feedbacks and indicators.between sensor feedbacks and indicators.

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Circuitry(cont)Circuitry(cont)

Sensing lack of lightSensing lack of light

– Under full incident light (spectral range of 515 nm ~ 730 nm ) , LDR, Under full incident light (spectral range of 515 nm ~ 730 nm ) , LDR, with its decreased resistance, renders the path to the LED inactive.with its decreased resistance, renders the path to the LED inactive.

– In darkness, its resistance increases. Op-Amp compares the In darkness, its resistance increases. Op-Amp compares the feedback and lights up the green LED.feedback and lights up the green LED.

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Circuitry(contCircuitry(cont))

Sensing heightened temperatureSensing heightened temperature

– Under increased temperature, the NTC type thermistor resistance is Under increased temperature, the NTC type thermistor resistance is decreased rendering it inactive in the circuit. Op-Amp again compares decreased rendering it inactive in the circuit. Op-Amp again compares the feedbacks and lights up the red LED.the feedbacks and lights up the red LED.

– When ambient temperature recedes to normal, the resistance increases When ambient temperature recedes to normal, the resistance increases cutting off power supply to the LED.cutting off power supply to the LED.

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Circuitry(cont)Circuitry(cont)

Part 2: Logistical ConsiderationPart 2: Logistical Consideration

Over the range of -50°C to Over the range of -50°C to 150°C, NTC thermistors 150°C, NTC thermistors offer a distinct advantage in offer a distinct advantage in sensitivity to temperature sensitivity to temperature changes compared to other changes compared to other temperature sensors like Pt-temperature sensors like Pt-RTD.RTD.

Thermistors are also easily Thermistors are also easily available and relatively available and relatively cheap.cheap.

Fig: Resistance Vs Temp Graph

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Circuitry(contCircuitry(cont))Light Dependent Resistors Light Dependent Resistors (LDR) provide a comfortable (LDR) provide a comfortable range of resistive outputs to range of resistive outputs to work with.work with.

Like the thermistor, LDRs are Like the thermistor, LDRs are also easily available and also easily available and relatively cheap.relatively cheap.

Variable resistors are used to Variable resistors are used to calibrate circuit in calibrate circuit in contemporary environment.contemporary environment.

Fig: Resistance Vs Light Intensity graph

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PurposePurpose

Reconnoitering through possibly radioactive or Reconnoitering through possibly radioactive or hazardous environment.hazardous environment.

Salvage mission over terrains unsuitable for Salvage mission over terrains unsuitable for human exposure.human exposure.

Charting terrain as a drone for possible thermal Charting terrain as a drone for possible thermal leakage , heat flux and variation is luminescence. leakage , heat flux and variation is luminescence.

THORTHOR at its infancy, is but only an engineering project. at its infancy, is but only an engineering project. However with proper planning it maybe employed in a variety However with proper planning it maybe employed in a variety of useful purposes:-of useful purposes:-

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Purpose (cont)Purpose (cont)

Animation showing THOR’s dynamic movements

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CritiqueCritique

Acrylic parts are vulnerable to sudden shock-loads.Acrylic parts are vulnerable to sudden shock-loads.

The wiring of the motors and DPDT switches often The wiring of the motors and DPDT switches often breaks loose.breaks loose.

The bead type thermistor is not as well responsive The bead type thermistor is not as well responsive as the LDR. So the signaling might be delayedas the LDR. So the signaling might be delayed

The wires used for gripper and arm-control is not The wires used for gripper and arm-control is not that strong in tension and might sever under heavy that strong in tension and might sever under heavy payloads.payloads.

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Optimization & Future plansOptimization & Future plans

Replacing acrylic parts with stronger materials, like Replacing acrylic parts with stronger materials, like HDPE (High Density Poly Ethylene) or Aluminum. HDPE (High Density Poly Ethylene) or Aluminum.

Integrating radio frequency control and servo drives.Integrating radio frequency control and servo drives.

Incorporating solar-power for prolong operation.Incorporating solar-power for prolong operation.

Automating directional commands via microcontrollers.Automating directional commands via microcontrollers.

Replacing LDR with more sensitive sensors such as Replacing LDR with more sensitive sensors such as phototransistors.phototransistors.

How to Optimize the current configuration?How to Optimize the current configuration?

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Optimization & Future plansOptimization & Future plans

Application in humanitarian services like Application in humanitarian services like minesweeping, scavenging battle debris.minesweeping, scavenging battle debris.

Stellar and interstellar explorations.Stellar and interstellar explorations.

What prospect does What prospect does THORTHOR’s future hold?’s future hold?

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ConclusionConclusion

At the end, we can only hope that we were At the end, we can only hope that we were able to achieve what we set out to do at able to achieve what we set out to do at the beginning of the course. We learned the beginning of the course. We learned much throughout the semester, about much throughout the semester, about mechanical and electrical components and mechanical and electrical components and most importantly about human resource most importantly about human resource management. However, all in all that was management. However, all in all that was quite a delightful experience.quite a delightful experience.

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AcknowledgmentsAcknowledgments

Dr. M.A. Taher Ali.Dr. M.A. Taher Ali.– Professor, Dept. of Mechanical EngineeringProfessor, Dept. of Mechanical Engineering

A.K.M Monjur MorshedA.K.M Monjur Morshed– Assistant Professor, Dept. of Mechanical EngineeringAssistant Professor, Dept. of Mechanical Engineering

Md. Wasim Akram Md. Wasim Akram – Lecturer, Dept. of Mechanical EngineeringLecturer, Dept. of Mechanical Engineering

Md. Al Amin Khan Chowdhury Md. Al Amin Khan Chowdhury – Lecturer, Dept. of Mechanical EngineeringLecturer, Dept. of Mechanical Engineering

Abdul Motin Abdul Motin – Lecturer, Dept. of Mechanical EngineeringLecturer, Dept. of Mechanical Engineering

Mr. Masudur Rahman Mr. Masudur Rahman – Assistant Instrumentation Engineer Assistant Instrumentation Engineer

For the completion of our project, we are greatly indebted to the following persons. For the completion of our project, we are greatly indebted to the following persons. Without their guidance, it would’ve been impossible to go through such an endeavour.Without their guidance, it would’ve been impossible to go through such an endeavour.

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Thank you all for joining in.Thank you all for joining in.

VisitVisit

http://project-http://project-thor.pbwiki.comthor.pbwiki.comIf you have any further queries.If you have any further queries.

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Q & A sessionQ & A sessionFeel free to askFeel free to ask