Line following with the Sparki robot.
Recommended lines: 3/4 inch white electrical tape on gray "Anti-Fatigue Foam Mat" (2 foot squares) as can be found at Harbor Freight. Turn the mats upside down (i.e. smooth side up) and put the various tape patterns on the squares. The squares can then be assembled into various track patterns.
The straight section gives Sparki an easy pattern to follow. It also can be used to see how well the program can capture a line by starting Sparki completely off the line, but pointing at the line at a shallow angle. As the near sensor goes over the line, Sparki will turn into the line. Ideally, the program will cross the line and capture it. A figure of merit for the program will then be how large of an angle can Sparki be to the line and still reliably capture the line.
The curved sections can be put together as a circle, which is very useful for testing the integral term of a PID loop. It can be combined with the straight sections to form an oval track. Substituting a zig-zag section for a stright section in the oval forms a tracking torture test.
Six curved sections can be combined with the crossover section to form a figure eight. A figure eight track is useful for verifying Sparki can follow both a left-hand and right-hand curve as well as traverse the crossover.
The crossover is used with curved tiles to form a figure eight track.
Example of a loop end section.
The zig-zag section can replace a straight section. This is a very difficult pattern to follow with just a PID loop.