Line Following Bot without using micro controller.

1. By
Rajat Verma

2. Following Lines
Simple device structure
Basic algorithm
Many ways to implement design

3. Research & Development

4. The Robot

5. 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

6. Sensory Systems
Photoresistors
Phototransistors
Photodiodes

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

8. Phototransistors
Current is sourced in the
presence of light
Moderately priced
Respond about 1000 times
faster than photoresistors

9. Photodiodes
Current is sourced in the
presence of light
Most expensive class of
photoconductors
Respond about 1000 times
faster than photoresistors

10. Data Processing &
Motor Control
Algorithm
Programmable logic device
Microcontroller

11. 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

12. Line Following Algorithm
Straight
Left
Right
Circle

13. Programmable Logic Device
(PLD)
Relatively inexpensive
Can easily implement finite state automata
Has limited program capacity
Has limited program capabilities

14. Microcontroller
Costlier than PLD
Relatively easy to program
Memory can be expanded, if needed

15. Drive Systems
DC motor
Stepper motor
Servo motor

16. DC (Toy) Motors
Abundant and cheap
Easy to implement
Provide no feedback regarding
motor speed or position

17. Stepper Motors
Expensive
Require special circuitry to
implement
Provide no feedback regarding
motor speed or position

18. Servo Motors
Very expensive
Provide feedback data
Require sophisticated
algorithms to implement

19. Research & Development

20. Phototransistors
Cost less than photodiodes
Have better reaction time than Photoresistors

21. PLD
Cheaper than microcontroller
More appropriate, given program size

22. DC Motor
Cheap
Will be run continuously
Does not need advanced features of servo

23. SNAP SHOTS TO
PROJECT

32. 32.