JOE: a mobile, inverted pendulum

The Industrial Electronics Laboratory at the Swiss Federal Institute of Technology, Lausanne, Switzerland, has built a prototype of a revolutionary two-wheeled vehicle. Due to its configuration with two coaxial wheels, each of which is coupled to a DC motor, the vehicle is able to do stationary U-turns. A control system, made up of two decoupled state-space controllers, pilots the motors so as to keep the system in equilibrium.