1. Robotics Training For The Riverside Robotics Society
4/24/2018
Learn Robotics At
Your Own Pace!
Line Following
Algorithms ,
Riverside, CA
Richard T. Vannoy II
Copyright 2016, Richard T. Vannoy II
Copyright 2004, Richard T. Vannoy II

2. 3 Control Structures
Selection Iteration
Or Decision or Loops Sequence

3. select case command

4. Some Definitions
Level 1: A Level 1 robot will never beat Level 2 or Level 3 robots.
Level 2: A Level 2 robot will always beat a Level 1 robot, and will never beat a Level 3 robot.
Level 3: A Level 3 robot will always beat Level 1 and Level 2 robots.

5. Make a Block Diagram

8. How Many Sensors???? I recorded the following results:
2 sensors: 40% Not recommended
3 sensors: 15% Not recommended
4 sensors: 25% Satisfactory
5 sensors: 15% Best Choice #1
6 sensors: 5% Best Choice #2

9. Infrared sensor circuit
10k
220
Schematic
Photo of actual circuit

11. R185 Single IR Sensor

13. 8 Sensor Arrays

14. Motors or Servos???
…Easy decision…
NEVER USE SERVOS unless the rules require them, or that is all you have and you cannot get any motors!

15. 5 Sensor Algorithm
0 = sensor above white 1 = sensor above black Lost line from overshoot or break in line Almost off the line, steer hard right and reduce speed Near the right edge of the line, steer right Right of the center of the line, steer right Slightly to the right of the center of the line, slight correction to the right Centered over line, increase speed for straight runs Slightly to the left of the center of the line, slight correction to the left Left of the center of the line, steer left Near the left edge of the line, steer left Almost off the line, steer hard left and reduce speed Line intersection or circle at end of maze

16. PID = Proportional, Integrative, Derivitive

17. Blue Line = Input (On or Off the Line) Dotted Lines = With Different PID Settings Red Line = Ideal PID Setting

18. Sensor Spacing is IMPORTANT!!

19. Level 1: Notice  Bang-Bang Motion  Very jerky  Little forward progress

20. Level 1.5: Notice  Much smoother  Tap, Tap Sound  Four Sensors

21. Level 2: Notice  Smoother  Five Sensors  Wires Wiggle

22. Level 3: Notice  180 Degree Turn before start is to calibrate sensors for ambient light.

23. Line followers:
Slow - differential steering
Slow - servo front wheels
Slow - detects line intersections
Medium speed - reverses at end of line
PID
Fast

24. Memory. Right-hand rule. Speeds up on pass 3.
Line Mazes:
Memory! Great!!
Memory. Left-hand rule
Memory. Right-hand rule. Speeds up on pass 3.

25. MicroMouse http://www.youtube.com/watch?v=hYPkjKgzXXw
Faster each pass!!

26. Several contests. Much to see/comment on.
Sumo
Several contests. Much to see/comment on.
FAST!! With replays

27. Obstacle Avoidance
Line follower that avoids obstacles, backs up.
Uses Laser
Basic avoidance behaviors

29. Copyright 2016, Richard T. Vannoy II
The End
4/24/2018
You Can Learn
Robotics At
Your Own Pace!
Copyright 2016, Richard T. Vannoy II
Copyright 2004, Richard T. Vannoy II