Kinematic Analysis and Parameter Sensitivity to Hard Points of Five-Link Rear Suspension Mechanism of Passenger Car

An existing kinematic model is discussed in this paper for its suitability for the kinematic analysis and synthesis of five-link rear suspension mechanism of a passenger car. The formulations for the trajectory of wheel center and contact patch along with other basic suspension kinematic parameters, as a function of wheel jounce and rebound are discussed and simulated. A model of the suspension is built in Multi-body Dynamics software ADAMS/view to validate the discussed model. The simulation results of kinematic model are found to be influenced by magnitude of the assumed velocity component of wheel center, however when a small magnitude of velocity is assumed as the input to the model the results match with the ADAMS model. A sensitivity analysis method is discussed in this paper which reveals the influence of suspension joint locations on the wheel center trajectory and other kinematic parameters. The information obtained from the sensitivity analysis can be effectively used for tuning of the hard points to obtain desired kinematic parameters. Using the results of sensitivity analysis, two of the hard points of an existing suspension are relocated and was verified by kinematic analysis of the modified suspension that the modification had resulted in an improved camber variation with a slight compromise on ride height.