Parameters Optimization Of Car Ride Comfort Based On Particle Swarm Optimization

When automobiles are in the process of running, uneven road surface will lead to vibration. When the intensity of vibration exceeds certain limit, passengers will feel uncomfortable and tired, goods will be damaged. On the other hand, intense vibration has an influence on automobiles'life and handling and stability. Accordingly, good capability of decreasing the vibration caused by road surface is demanded; viz. good automobile ride comfort is demanded.Primary factors can influence automobile ride comfort are form and parameters of suspension, viz. suspension stiffness, suspension damp and their combination. When the form of suspension was confirmed, more reasonable parameters can be selected by optimization method to improve automobile ride comfort.Particle Swarm Optimization is a swarm intelligence optimization algorithm that was publicized recently. Particle Swarm Optimization is simple and suitable for nonlinear problems. It can converge quickly and find optimal solution accurately. Because of these advantages, Particle Swarm Optimization has acquired extensive applications in engineering optimization. However, few people apply this method to optimization of automobile ride comfort. This article is for the purpose of applying PSO to parameters optimization of automobile ride comfort. Main content of this article is as follows: Research of basic PSO. Its basic principle, characteristics, parameters setting, process of algorithm, flowchart and several kinds of improved Particle Swarm Optimization have been introduced. Its program based on MATLAB has been developed. In order to test the optimization capability of PSO, a contrast between PSO and complex method has been made. The result of optimization and the graph show that, for a complicated multi-peak optimization problem, PSO is simpler, can find optimal solution exactly and has an advantage over traditional optimization methods.After study of two DOF vibration model of 1/4 automobile, the mechanics and mathematics model, amplitude-frequency characteristic formulae and power spectrum density function of three responses have been summarized. Three elements of optimization have been confirmed. A simulation optimization program based on PSO has been developed. PSO has been applied to the optimization model and optimization result has been analyzed and contrasted. This part of work explores the feasibility of applying PSO to a small quantity DOF automobile vibration model and has very good effect. It establishes a firm basis for optimization of high quantity DOF automobile vibration model.After study of eight DOF vibration model of 1/2 automobile, the mechanics and mathematics model, amplitude-frequency characteristic formulae and power spectrum density function of six responses (perpendicular acceleration of front and rear body, dynamic flexibility of front and rear suspension, relatively dynamic load of front and rear wheels) have been summarized. Three elements of optimization have been confirmed. A simulation optimization program based on PSO has been developed. PSO has been applied to the optimization model and optimization result has been analyzed and contrasted. The graphs of perpendicular acceleration of bodies, dynamic flexibility of suspensions and relatively dynamic load of wheels show that, perpendicular acceleration of front and rear body reduces obviously and dynamic flexibility of front and rear suspension and relatively dynamic load of front and rear wheels are within the range of boundaries. Obviously, the optimization is effective.This article tries to apply PSO to parameters optimization of automobile ride comfort and gets very good result. It provides a new method for parameters optimization of automobile ride comfort.