Vehicle suspension system

A vehicle suspension system for plural vehicle wheels comprising support means disposed between each wheel and a vehicle body exerting suspension force which can be changed irrespective of relative displacement between the wheel and the vehicle body, a separate sensing means for each wheel for detecting one of the parameters representing changing condition of the relative displacement between the wheel and the vehicle body, control means for controlling the respective support means when supplied with a signal from the respective sensing means, by extracting low frequency components therefrom and, according these components, controlling the support means to exert the suspension force in such a way that said relative displacement can be suppressed, wherein each support means includes a fluid actuator having a fluid cylinder disposed between the respective wheel and the vehicle body, the system further including a fluid reservoir, pumping means for supplying pressurized fluid from the reservoir to the respective fluid cylinders, and a separate valve means interposed between the pump means and the respective cylinders for controlling fluid flow applied to and discharged from the respective cylinders, and wherein said control means controls each of said valve means so that pressurized fluid is applied to and discharged from each of said cylinders to exert suspension forces from each fluid actuator according to each of said displacements.