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This robot was built to learn PID control of motors, I use IR shining through holes in the one of the gears in the gear box. IR is used for Ring Edge detection and finding the other robot. I has been modified to test various ideas such as playing with the cheap 433MHz RF modules. Wheels are turned Alu and the body is Al sheet and angle. The electronics are all on Perf board, mainly wire wrapped.
This is a companion discussion topic for the original entry at https://community.robotshop.com/index.php/robots/show/old-mini-sumo-robot