Orientation tracking control of mobile robot with three trailers

The orientation tracking control problem of a mobile robot with three on-axle trailers in backward motion is addressed in this paper. Due to the fact that the trailer system is not open-loop stable, it is a challenging work even for experienced drivers to reverse the robot stably. The control law is designed based on a reformed cascade and interconnected system. By introducing the input-to-state stability, the proposed control law is proven to be asymptotically stable. Numerical simulation results shows that the proposed control law can successfully reverse the robot stably to track the desired orientation angle with asymptotic convergence.