Vehicle Body Height Control And Static Ride Research Based On Active Oil-air Suspension

The ground clearance will not be affected by external load after installing the activeoil-air suspension on the car. The body height will soon be restored to the pre-set value byadjusting the control system when the weight is changing. Oil-air suspension use metalcontainers equipped with inert gas as the elastic element, the damping effect is achieved byflowing the damping orifice of the oil. With the development of hydraulic and controltechnology, oil-gas suspension tends to the direct of active control. In this article, the vibrationcharacteristic of vehicle system was researched, then the body height control principle wassimulated based on AMESim. The main works are as follow:Firstly,the natural frequencies of the two degrees of freedom vehicle vibration systemwere solved and obtained the main mode shape corresponding to each natural frequency, thetransfer curves were also obtained. The results showed that the wheel vibration excited fromthe road makes a predominant factor, almost no vibration energy transmit to the vehicle body.Followed,the equivalent oil-air spring which was combined with the hydraulicproportional servo control system was designed, the ground clearance of the vehicle body wascontrolled by selecting the gain of the amplifier to eliminate the position error between bodydisplacement and wheel displacement.At the same time,the class B road model was established in AMESim and obtained themain evaluation indicators of car ride analysis which were vehicle body acceleration responseunder different speed and acceleration power spectral density,and the effects of inherentparameters to the ride analysis were also researched.At last,the ride analysis was carried out on the virtual prototype of Mcphersonindependent suspension and finite element analysis and modal analysis were also performed on the control arm, to provide references for the optimize design of the wheel alignmentparameters and control arm as well as provide the vehicle’s anti-vibration process a theoreticalbasis.