SWITCHING CONTROL OF A TRACTOR-TRAILER WHEELED ROBOT

Tractor-trailer systems have been widely used to increase load transportation capacity. Control of these systems started from motion aid facilities in human-driven vehicles, to fully autonomous mobile robots in recent years. In fact, tractor-trailer wheeled robot (TTWR) has been proposed as a modular robotic system in which an actuated mobile robot tows (a) passive trailer(s). The mobility of such highly non-linear systems is restricted due to the presence of non-holonomic constraints of wheels, also the system severe underactuated nature. These conditions generate major difficulties in system stabilization, i.e., to park or reach a given configuration for the overall system. This leads to a challenging control problem for research that is the focus of this paper. To this end, dynamics model of the TTWR is first developed. Next, a switching kinematic controller is designed to stabilize the system around a desired configuration. The proposed kinematic control algorithm is developed based on switching between several finite-time controllers. Then, a non-model-based dynamics controller is developed to produce actuator torques, which demands low computations for real-time implementations. Experimental results reveal the merits of the proposed controller that could be a promising efficient controller for corresponding industrial applications.