Control of a Mobile Robot Subject to Wheel Slip

Wheel slip is inevitable when a Wheeled Mobile Robot (WMR) is moving at a high speed or on a slippery surface. In particular, when neither lateral nor longitudinal slips can be ignored in the dynamic model, a WMR becomes an under-actuated nonlinear dynamic system. To study the maneuverability of a WMR in such a realistic environment, we model the overall WMR dynamics subject to wheel slip and propose control algorithms in regulation control and turning control tasks for the WMR. In regulation control, a time-invariant discontinuous feedback law is developed to asymptotically stabilize the system to the desired configuration with exponential convergence rate. In turning control, a sliding mode-based extremum seeking control technique is applied to achieve stable and sharp turning. Simulation results are presented to validate the theoretical results.