Modeling, Simulation, and Control of Active Pneumatic Suspension System

This paper presents analytical modeling, system identification, and controller design for a “pneumatic-only” vibration isolation system. There exist extensive literature on traditional suspension designs but the literature on purely pneumatic suspension devices is very sparse. This paper presents an extensive modeling and experimental work for characterizing dynamical behavior of the system. The experimental data was used to derive approximate but simple low-order dynamic models using system identification techniques. A solenoid operated orifice mechanism is used to control the flow of air mass between air spring and accumulator. The design of accumulated air spring with controlled orifice constitutes a Continuously Variable Natural Frequency and Damping (CVNFD) device introduced in previous work by the second author. The paper also presents a robust control analysis and design for disturbance rejection problem. The results show promising trends for potential use of such simple and inexpensive system in various vibration isolation applications.