Nonlinear Dynamics Analysis of Car-trailer Combinations Body Sway considering Steering System Damping

Body sway is a complex nonlinear dynamic behavior of road vehicles. Because of the dynamic coupling between the towing car and the trailer, body sway is more likely to occur in car-trailer combinations. The research has shown that the suspension system and wheel system both have an important impact on the body sway and the corresponding influencing mechanism has been analyzed systematically. Experimental study indicates that the steering system characteristics have influence on body sway of car-trailer combinations. However, this effect has not been confirmed by any theoretical studies, so this paper aims to find out the effect of steering system damping on body sway. For this purpose, a 6-DOFs nonlinear single-track model including the steering system of car-trailer combinations is established by Lagrange equation. Multi-equilibrium bifurcation analysis, time domain analysis and sensitivity analysis are applied to study the influence mechanism of steering system damping on body sway. Results of this theoretical research can be served as a guidance for the design of the steering system of car-trailer combinations.