Multi-objective Optimisation of McPherson Strut Suspension Mechanism Kinematics Using Random Search Method

McPherson suspension mechanism is one of the widespread mounted mechanisms in front axle of Front Wheel Drive (FWD) vehicles with transverse engine. In this study the kinematics of McPherson suspension mechanism is optimised in order to achieve the desired kinematic behavior and improve vehicle stability. First, the mechanism was modeled in Mechanical Desktop software package and the model transferred to Working Model 3D software for kinematic analysis. Then results of kinematic simulation compared to design criteria and as target function is established, by choosing the optimal amount of optimisation variables the amount of cost function has been minimized. Because of simple implementability and also because of having the least influence on other specifications of the vehicle, the spatial location of joints selected as optimisation variables and changing range of variables is set in a rational interval. The aforementioned procedure done for determined numbers of iteration by use of Random Search Method to obtain the optimum results. Results show that the employed method has the ability to optimise the mechanism kinematics in suitable spent time. In addition, it is seen that after optimisation the alteration of toe angle, camber angle, and track width were improved noticeably. Finally, in order to validation the optimised mechanism modeled in ADAMS.