Pendulum-balanced autonomous unicycle: Conceptual design and dynamics model

A new mechanism to balance an autonomous unicycle is explored which makes use of a simple pendulum. Mounted laterally on the unicycle chassis, the pendulum provides a means of controlling the unicycle balance in the lateral (left-right) direction. Longitudinal (forward-backward) balance is achieved by controlling the unicycle wheel, a mechanism exactly the same as that of wheeled inverted pendulum. In this paper, the pendulum-balancing concept is explained and the dynamics model of an autonomous unicycle balanced by such mechanism is derived by Lagrange-Euler formulation. The behavior is analyzed by dynamic simulation in MATLAB. Dynamics comparison with wheeled inverted pendulum and Acrobot is also performed.