Multi-objective Optimization And Analysis Of Multi-link Suspension Hardpoint Coordinates

With the rapid development of automotive industry, people pay more and more attention to the requirement of automotive performances,such as good economy、 power performance、good handling stability、ride comfort and the higher safety. Suspension is an important systerm, which affects the vehicle comprehensive performance. Automotive safety, ride comfort and handling stability are closely related to the suspension K&C characteristics. Therefore, analyzing the suspension K&C characteristics is of great significance for improving vehicle handling stability.Multi-objective optimization about hard point coordinates of four-links suspension that affect suspension K&C characteristics is studied, which can improve the suspension K&C characteristics, and then enhance the vehicle operating stability. Firstly, multi-body dynamic simulation model of suspension is built, which is validated by the experimental data of suspension K&C characteristics. Secondly, the perturbation method is used to determine the main hard point coordinates that have main influence on the suspension K&C characteristics according to sensitivity analysis. And then objective functions between standardized design variables and suspension K&C characteristics key parameters are built by Design Expert software, which are optimized by using multi-objective genetic algorithm(MOGA). Some parameters’ range and maximum value decerase when wheel vibrating, such as wheel toe angle, camber angle and so on; some increase,such as suspension stiffness, roll stiffness and so on increases; and others have no change,such as wheel travel base, travel track and so on. Finally, the complete vehicle system is studied for the analysis of vehicle handling stability and ride comfort, and vehicle handling stability is improved under the same level of ride comfort.