Study On The Control Strategies And Simulation For Vehicle Seat Active Suspension

The performance of the vehicle’s driving smoothness, driving safety, riding comfort and handling stability depend on the merits of the vehicle suspension system performance. As vibration part member in direct contact with the human body, the main task of vehicle seat suspension and function is to load the body weight, to mitigate the impact of road excitation transfer to driver and finally to weaken the impact bring the body vibration. Seats in direct contact with the body, the body’s comfort depends directly on the degree of seat suspension damping performance. In particular, the seat suspension performance is poor easily lead to driving fatigue, this often lead to traffic accidents. Therefore, the active seat suspension system of vehicle has been a research hotspots in recent years.Thesis first introduces the research background, significance and the research status of seat suspension. Based on the relevant research at home and abroad present the main research contents; to summarizes the comfort requirements and evaluation methods as well as ride comfort evaluation index, The random road input mode and the simulation module are established. Simplify the seat suspension system, established the mathematical model of 1/2car with five degrees of freedom passive seat suspension system and active seat suspension system, and lists the corresponding Dynamic differential equation. Then, through the study of the control strategy, this paper ultimately selected PID control and Fuzzy PID control as control methods, and designed PID controller, Fuzzy PID controller take the actual speed and the desired speed difference as input. In the Simulink environment build a simulation module,and make simulation analysis. Simulation results show that the seat suspension system adopting the active control strategy improves greatly the seat’s vertical vibration of the seat and reduces effectively the vibration of the road uneven road surface passed to the driver. At the same time, the Fuzzy PID controller improves the performance of body vertical, pitch,dynamic load tire, suspension dynamic deflection and other performance indicators in different degree, increases the ride comfortability and improves vehicle’s overall performance.