Method for the quasi-static analysis of beam axle suspension systems used for road vehicles

Abstract

This paper addresses an analytical method for determining the static equilibrium position of beam axle suspension systems used of motor vehicles. This method is applicable to most types of suspension systems and is based on the definition of the spatial positioning of the guiding mechanism as a result of the forces and torques acting in the suspension system. The static model is defined in analytical form, in terms of virtual work, considering the system of applied forces and reactions in the elastic suspension elements (springs, bumpers, anti-roll bar and bushings), whose deformations are determined by the spatial positioning of the guiding mechanism. The proposed method is based on an iterative algorithm by which, for a given set of contact forces on wheels, the equilibrium position is identified by scanning the entire vertical motion domain of the wheels and selecting the configuration that ensures minimal static function. The results obtained by the algorithmization of the method and computer programming allow an accurate assessment of the static behaviour of a beam axle suspension system (in terms of equilibrium configuration and reaction forces) in various regimes, without the need for costly experimental testing.