Abstract: An active suspension system for a vehicle employing fluid powered force exertion units between the wheels and the vehicle body. The vehicle's engine operates a pump which provides pressurized fluid to operate the force exertion units under the control of a processing unit which monitors the rate of change of the power being consumed by the force exerting units and stores demand data indicative of the prior history of power demands placed on the engine by the suspension system. The processor calculates an autoregression moving average of the stored past demand values to form a prediction of future demand, thereby controlling the amount of power delivered by the engine in anticipation of the predicted needs of the force exertion units.

Abstract: An active suspension system for a vehicle having sprung and unsprung masses including a powered source of pressurized fluid coupled to a processor. The processor calculates the rate of change of the power being consumed by the source and controls that rate of change whenever the calculated rate exceeds a predetermined value.

Abstract: A vehicle suspension system having active and passive modes, comprising fluid providing means for providing a pressurized fluid, a cylinder, having at least two chambers, protection valve means having first and second states, for coupling the fluid providing means to the cylinder in the first state and uncoupling the fluid providing means from the cylinder in the second state, and by-pass valve means, having at least first and second states, being fluidly coupled to the cylinder and the protection valve means, for providing fluid communication therethrough between the chambers in the second state and not providing fluid communication therethrough between the chambers in the first state, and wherein the protection valve means is in the first state when the suspension system is in the active mode and the protection valve means and the by-pass valve means are in the second state when in the passive mode.