Abstract
The wheeled inverted pendulum robots whose control methods are discussed in this paper can move on a two dimensional horizontal plane by controlling two wheels. The horizontal motion is nonholonomic like the motion of two wheeled vehicles. However, the translational acceleration of inverted pendulum robot is used for stabilizing the body angle. Therefore, the translational velocity is not considered as an independent control input in the tracking problem of nonholonomic system. In this study, a tracking controller for inverted pendulum robots is proposed. Two control inputs of the system are separately designed by using the transformation to the time-state control form. At first, the translational control input is designed for stabilizing the body angle and controlling the translational velocity. Then, the rotational input is designed based on the time-state control form of the horizontal motion model in order to asymptotically converge to given trajectories. In numerical simulations and experiments, it was confirmed that the robot tracked given desired trajectories even if the translational velocity fluctuated.
