RESEARCH FOR THE VEHICLE SEMI-ACTIVE SUSPENSION SYSTEM BASED ON IMMUNE-PARTICLE SWARM OPTIMIZATION ALGORITHM

In order to improve vehicle handling stability and ride comfort,the vehicle semi-active suspension system is researched.We establish the 1/4 vehicle three degree-of-freedom suspension mathematical model,which contains a simplified model of the suspension system lateral displacement,and infers the suspension dynamic equation and the equation of state.Furthermore,we propose a new Immune-Particle Swarm Optimization algorithm and design Immune-Particle Swarm Optimization controller which is applied in suspension system's control.Compared with fuzzy control results,the Immune-Particle Swarm Optimization control method reduces separately 38.64%、20.53%、60.60% and 23.39% of the maximum peak value of automobile body vertical acceleration,suspension dynamic travel,wheel relative moving load and suspension lateral displacement.In addition,the method reduces separately 0.45s、0.6s、0.4s and 0.6s of the stabilization time.The simulation result indicates the control algorithm in the improvement controlled process's tendency and the stable state performance,sharpens aspects and so on anti-interference ability as well as parameter time-variable parameters surpasses the fuzzy control method,while improves the semi-active suspension system damping performance obviously.