The PulleyBot is a simple, single actuator 3D printed toy with a transmission entirely made up of pulley systems. This instructable is a tutorial on how to assemble the PulleyBot, but if you are interested in pulley, cable, and chain mechanisms, then I would suggest checking out this Pulley Mechanisms Instructable. I hope you have fun building this, and even more fun designing your own!
PulleyBot is entirely driven by belt and pulley systems, which are a type of mechanical transmission. A belt is basically a loop of material, be it a bike chain, a rubber band, or a tank tread, that can be used to transmit mechanical power. It is looped around sets of pulleys, which are simply wheels with grooves or teeth in them for the belt to catch on. As a pulley rotates about an axis, it drives the belt via friction between the belt's surface and the groove of the pulley. This in turn drives the other pulleys linked to the same belt. PulleyBot is a simple system composed of multiple belts and pulleys rotating multiple axes to drive the robot forward.