Guidance of a Robotic Off-Road Tractor-Trailer System Using Model Predictive Control

Abstract

This paper presents a nonlinear Model Predictive Control approach to controlling a tractor-trailer system. Using a nonlinear tractor-trailer model, the controller determines the optimal steer angle, based on the trailer’s measured position and heading, as well as information about the path geometry in front of it. Then, the computer determines the amount of voltage to apply to the steering wheel motor to achieve the necessary steer angle. In the simulation study, the controller algorithm is capable of guiding a 2-1/2 meter long trailer around a 5-meter radius turn, towed by a four wheel drive off-road utility vehicle, with a maximum error of 8.5 centimeters.