D.A.V.E. Robot Construction Project

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D.A.V.E.Robot Construction Project

• Lara Cowan
• Victor Johnson
• Hector Malagon
• Michael Zaw

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Following Lines

• Simple device structure
• Basic algorithm
• Many ways to implement design

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Research Development
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The Robot
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Overview

• Sensory systems
• Data input systems Collect information of
  outside world
• Data processing/motor control
• Systems to interpret input signals and decide
  what to do
• Drive systems
• Output systems for machine Implement signals
  from motor controller

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Sensory Systems

• Photoresistors
• Phototransistors
• Photodiodes

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Photoresistors

• Resistance is inversely proportional to light
  levels
• Cheapest of the three types of photoconductive
  devices
• Have the slowest reaction rate of all
  photodetectors

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Phototransistors

• Current is sourced in the presence of light
• Moderately priced
• Respond about 1000 times faster than
  photoresistors

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Photodiodes

• Current is sourced in the presence of light
• Most expensive class of photoconductors
• Respond about 1000 times faster than
  photoresistors

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Data Processing Motor Control

• Algorithm
• Programmable logic device
• Microcontroller

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Line Following Algorithm

• Robot direction is determined by what the robot
  sees
• If line is centered in front of robot, go forward
• If line is left of center, turn left
• If line is right of center, turn right
• If no line is detected, circle until line is found

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Line Following Algorithm

• Straight
• Left
• Right
• Circle

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Programmable Logic Device (PLD)

• Relatively inexpensive
• Can easily implement finite state automata
• Has limited program capacity
• Has limited program capabilities

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Microcontroller

• Costlier than PLD
• Relatively easy to program
• Memory can be expanded, if needed

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Drive Systems

• DC motor
• Stepper motor
• Servo motor

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DC (Toy) Motors

• Abundant and cheap
• Easy to implement
• Provide no feedback regarding motor speed or
  position

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Stepper Motors

• Expensive
• Require special circuitry to implement
• Provide no feedback regarding motor speed or
  position

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Servo Motors

• Very expensive
• Provide feedback data
• Require sophisticated algorithms to implement

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Research Development
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Phototransistors

• Cost less than photodiodes
• Have better reaction time than Photoresistors

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PLD

• Cheaper than microcontroller
• More appropriate, given program size

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DC Motor

• Cheap
• Will be run continuously
• Does not need advanced features of servo

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THE END