Path tracking control for a robot-trailer system in the presence of measurement bias

Abstract

In this paper, the authors design a controller for a robot-trailer system to solve the path following problem. A kinematic state-space model is derived using tractor steering angle rate as system input so that undesirable effects of input disturbances can be reduced. A tracking error of the trailer position may exist when there are biases on the measurements of heading angles. An improved integral separation combined with linear quadratic regulator (LQR) is designed for the system to remove the trailer position error. The tractor relative location is used to estimate whether the system is under steady state. The controller with integral action can be difficult to tune, so a genetic algorithm (GA) is then used to find optimal LQR controller parameters. Simulation results verify the approaches above.