### Title: Calculation of joint forces of a multi-link suspension for strength and fatigue analysis of bushings and control arms

Authors: Xiao-Li Wang; Lin Dai; Wen-Bin Shangguan

Addresses: State Key Laboratory of Automotive Simulation and Control, Jilin University, Jilin 130012, China; School of Mechanical and Automotive Engineering, South China University of Technology, Guangzhou 510641, China ' State Key Laboratory of Automotive Simulation and Control, Jilin University, Jilin 130012, China; School of Mechanical and Automotive Engineering, South China University of Technology, Guangzhou 510641, China ' State Key Laboratory of Automotive Simulation and Control, Jilin University, Jilin 130012, China; School of Mechanical and Automotive Engineering, South China University of Technology, Guangzhou 510641, China

Abstract: The joint forces and moments of a multi-link suspension are important parameters for fatigue analysis and experiment of bushings and control arms in the suspension. A modelling and calculation method for obtaining the joint forces and moments for a multi-link suspension is developed. In modelling of a multi-link suspension, a bushing is modelled with three translational stiffness and three torsional stiffness along and around three orthogonal axes. The force vs. displacement along one axis is non-linear and simplified as piecewise linear. Taking a rear five-rod suspension as one example, the forces and moments for each joint are calculated with the proposed method and compared with that using a conventional method. It is shown that the proposed model and calculation method can be used to evaluate the joint forces and moments for determining input loads for the design and fatigue test of bushings and control arms in a multi-link suspension.

Keywords: multi-link suspension; nonlinear bushing; joint forces; moment calculation; control arm; fatigue analysis; strength analysis; vehicle design; vehicle suspension; modelling; translational stiffness; torsional stiffness; orthogonal axes; displacement.

International Journal of Vehicle Design, 2014 Vol.66 No.3, pp.217 - 234

Available online: 09 Nov 2014 *