A procedure for selecting the lateral characteristics of tires from the aspect of minimal yaw of the passenger motor vehicle's trailer

Abstract

In the initial phase of motor vehicles design, and therefore their trailers, the dimensions and type of tires are adopted according to the required payload, from the manufacturer's catalogue. The fine-tuning of the characteristics, especially the lateral characteristics of the tires, is carried out in the later stages of design, using models or experimental methods. The yaw of the trailer, as part of the passenger vehicle-trailer system, using its simple dynamic model, is analysed in this paper. The equations of motion were derived using the Newton's laws for constant longitudinal velocity of a vehicle. Tires are described by models based on higher degree polynomial approximation. Optimal selection of the corresponding parameters of the lateral characteristics of the tires was made using the Hooke-Jevees method. Constructive parameter constraints have been introduced by the use of external penalty functions. The optimization process of minimizing the trailer's yaw angle was started with three sets of initial values of the optimizing parameters. Analyses have shown that it is sufficient to start with the midpoint of the parameter definition interval and the obtained data enable a quick selection of the lateral characteristics of the trailer's tires at the conceptual stage of its design.