Output Feedback Stabilization of Nonholonomic Wheeled Mobile Robot Using Backstepping Control

A novel output feedback posture stabilization of wheeled mobile robot (WMR) is presented to overcome the challenges faced by posture stabilization of WMR. A generalized normal form of WMR is developed by a suitable change of coordinates via input-output feedback linearization approach, with the restriction of nonzero initial condition of orientation angle. The internal dynamics is in a strict feedback form that provides an ease to implement a regular integral backstepping control technique. The control law achieves asymptotic stabilization of both the internal and external dynamics of mobile robot. The control design of state feedback is further enhanced to output feedback control utilizing a full order high gain observer. It is shown that estimated states converge to true states rapidly with good transient behavior. Stability analysis of the overall system is proved using Lyapunov method.