Tracked robots usually require at least two wheels inside to work properly. However, [James Bruton] discovered a curious tractor design from the 1940s, the Fordson Rotaped, which only uses a single sprocket wheel inside each track. Being [James], he built a self-balancing robot around the rotaped concept.
Instead of a lot of short track sections, the Rotaped uses six long sections of track, about the same length as the wheel’s diameter. To keep the track on the wheel, a series of chains or an oval frame is used on the inside of the track.
As is usual for [James]’ projects, most of the mechanical parts are 3D printed. To hold the tracks in place, he stretches a bungee cord loop around three points on each side of the track. To make things more interesting, he made the robot balanced on the tracks. This took a bit of PID tuning to get working … // Read more: original article.
