Pneumatic Vehicular Suspension With a Controllable Stiffness Spring

This paper deals with the design of a new vehicular pneumatic suspension. It presents an innovative scheme of suspension, using a special 3-membrane deformable fluid spring. The spring is provided with three internal chambers, supplied by a compressible fluid. Each chamber presents a different volume gradient versus the stroke; a proper variation of the connection between the chambers, that may be performed in few milliseconds, determines a stiffness variation of the air spring. The spring structure and the related mathematical models are presented. Afterwards the process of adaptation of the component to a specific mid-low class car model, in order to achieve a prototypal phase, is described. Finally the results of some dynamic simulations of the car behavior are shown.