Lateral position control for a tractor-trailer system using steering rate input

In this paper, the authors present a trailer lateral position controller for a non-collocated tractor-trailer system, using steering rate instead of steering angle as control input variable to reduce the tracking error when reference path is a curve. Coordinate transformation is defined at each control sample. Linear quadratic regulator (LQR) is used to eliminate lateral position error. The constraints on steering rate, steering angle and angle difference between tractor and trailer are considered. Simulation results show that the system is able to track lines and curves for both forward and backward motion.