An electric unicycle(often initialized as EUCor acronymized yukeor Uni) is a self-balancing personal transporterwith a single wheel. The rider controls speed by leaning forwards or backwards, and steers by twisting or tilting the unit side to side. The self-balancing mechanism uses accelerometers, gyroscopes, and a magnetometer.

A self-balancing electric unicycle consists of a frame+pedals that the rider stands on, a motor where the stator is attached to the frame+pedals, and a rotor which is attached to the wheel+tire. An EUC is similar to an inverted pendulum: the EUC frame is free to rotate about its axis, limited by motor torque.