The PID Rug Bump Challenge is the ability for a small robot (with 35mm radius wheels) to confront the edge of a thick Kilim rug (17mm thick) with one wheel without being deterred from its path, i.e., recovering from that bump whilst maintaining its original heading.
The "ideal" behaviour would be follows, quoting David Anderson of the DPRG:
Even at very low torque/low speed the robot rotates through maybe a
degree before mounting the carpets, and then once mounted the PID
controller over-corrects and that straightens it out onto the original
path. So a little figure 'S'. At higher speeds it just goes straight
over the elevated carpet, with no change in the path.
Tuning the PID Controllers so that they respond in kind is the challenge.
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