Control Allocation for Wheeled Mobile Robots Subject to Input Saturation

Abstract

This paper addresses the problem of input saturation in wheeled mobile robot control. Depending on the desired trajectory or on the terrain, wheel motors may be demanded to work beyond their limits. This situation can lead to undesired performance, and therefore, input saturation has to be properly managed. Although control allocation has been mainly employed in overactuated systems to enhance the control distribution, it can be also utilized for underactuated systems as well to grant performance. For this purpose, three different control allocation strategies, along with Lyapunov-based time-varying feedback controller, are applied to a differential drive mobile robot subject to input saturation. Experimental results illustrate the performance of the proposed strategies.