Improve Safety by Optimal Steering Control of a Converter Dolly Using Particle Swarm Optimization for Low-Speed Maneuvers

This paper offers a solution to the problem of poor path-following performance of high capacity transport (HCT) vehicles, such as A-double combinations, causing safety issue for the vulnerable road users during low-speed turning maneuvers. An advanced control strategy is developed which only demands the axles of the converter dolly of such vehicle to be actively steerable so that existing tractor and semitrailers can be used without any further modification. The control strategy described in this paper allows the change of forward speed and even to stop the vehicle completely during the turning maneuver without any performance degradation. The controller utilizes the delays of tractor front axle steering angle and the articulation angles measured not in traditional time but in path-distance domain. The optimal controller is achieved using particle swarm optimization (PSO) technique. Finally the optimal vehicle performance is compared with a baseline non-steerable converter dolly case and also with a proportional control case. Significant improvement in path-following performance is observed.