Wheel servo control based on feedforward compensation for an autonomous mobile robot

Abstract

In the paper, we propose a wheel controller with feedforward dynamic compensation. A wheel control system developed for autonomous mobile robots driven by two wheels is described. In the navigation of such mobile robots, large path error occurs mainly due to the disturbance from the floor and the uncompensated dynamics inherent to robot motion. The stable and robust motions in the tracking stage are often difficult to achieve without consideration of wheel dynamics. The feedforward controller is designed based on an approximate inverse model which can be obtained via a series expansion of the plant inverse model. In order to adapt to changes in the environments, the controller is implemented as an adaptive version by employing the online parameter estimator. To demonstrate the validity of the proposed controller, a series of path tracking experiments were conducted for a prototype mobile robot, LCAR, by combining it with a path tracking controller.