Robust path tracking control of nonholonomic wheeled mobile robot: Experimental validation

The article addresses a robust control strategy for efficient path tracking of nonholonomic wheeled mobile robot (WMR) based on time delay approach. Depending on the application requirements, nonholonomic WMR system might be subjected to various payloads, which affects the overall system mass, inertia, position of center of mass and other hardware parameters statically or dynamically. Under such circumstances, accurate modeling of nonholonomic robots is difficult and challenging. The proposed controller negotiates uncertainties caused due to payload variations as well as associated disturbances and reduces modeling effort through approximation of the overall uncertainties with a composite function. It has been shown that the controller does not require any bounds on the uncertainties, thus providing unconstrained working paradigm. The controller is proposed for a nonholonomic WMR and its effectiveness is verified through simulation and experimentally while WMR is commanded to track various paths. The superior performance is also noted against adaptive sliding mode control law.