Optimisation of tractor semi-trailer command steering mechanism using a genetic algorithm

Abstract

Steering the rear wheels of semi-trailers has become common to improve the manoeuvrability of the vehicle. Command steering is one of the methods of steering semi-trailers. Depending on the articulation angle, a mechanism steers the rear wheels accordingly. In this paper, this mechanism is optimised to meet three goals. The first goal is staying within the boundaries of the road for specific tests. The second goal is to decrease tyre wear. The third goal is to minimise the difference between the trailer hub angles caused by the left and right hydraulic pistons of the steering system. All of these goals are achieved using a genetic algorithm by searching the parameter space. The hydraulic and mechanical command steer system is also modelled and used in the optimisation process. The complete system is optimised so that the semi-trailer wheels approximate the Ackerman condition as closely as possible.