Trajectory-Tracking Sliding-Mode Control of the Autonomous Wheelchair Modeled as a Nonholonomic WMR

This paper deals a new approach of the trajectory-tracking second-order sliding-mode control (TT-SOSMC), applied to control a nonholonomic wheelchair for elderly and disabled based on kinematic model. Cirrus Power Wheelchair (CPW) was modelled like a wheeled mobile robot (WMR) with two driving and two free wheels (2DW/2FW). A hardware description, concerning driving wheels control, data acquisition and communication with PC and touch screen, is presented. Simulations and real time results have presented taking into account parameter uncertainties and external disturbances. CPW closed loop control, via simulation and real-time have proved improved performance in terms of decreasing reaching and settling times with increasing robustness.