Design and validation of high speed active trailer steering system for articulated heavy vehicle

Abstract

Articulated heavy duty vehicles are widely used around the world for its economic and environmental benefits. A-train double is one of the most popular heavy duty vehicles in Canada. Despite its advantages, the spread of A-train is hampered by poor lateral dynamic performance and poor accident avoid ability in highway resulted from its special structure. In order to evaluate the lateral dynamic performance of the A-train double at highway speed, ISO standards have proposed the rearward amplification (RA) measures to characterizing the performance. It has been reported that the RA curves obtained through three different methods proposed by ISO-14791 differ. This thesis studies three proposed methods in detail and analyzes the contributing causes for the inconsistency among three test maneuvers based on A-train double. In order to increase the lateral stability of the A-train double, Active steering systems (ATS) have been designed through two methods: robust LQR-LMI method with genetic algorithm (GA) optimization and H∞ method. The designed controllers are validated by numerical simulation and hardware in-loop simulation. The ATS designed from two methods show good robust stability and improve the lateral dynamic performance of A-train double dramatically at highway speed.