Tumbler Bot

I wanted to design a robot that contained only a single moving part, and that could travel in any direction instantaneously. The result was a generalization of those rolling ball robots that have a little wheeled vehicle inside: As the vehicle tries to ride up the inside of the ball, the weight shifts inside (to keep the vehicle near the bottom), and the ball rolls.

In the case of the TumbleBot, the outer sphere is made of metal, and the inner core contains six electromagnets. The core assembly tries to climb up inside the sphere by turning on selected electromagnets. This causes the center of gravity to shift, and the ball rolls.

By turning on different electromagnets, the TumbleBot can shift direction instantly (as in the simulation at right).

- Ken Perlin

Source: tumbler2.java