Robust control and μ analysis of active pneumatic suspension

This paper presents a novel concept of active pneumatic suspension which uses an accumulator, airspring, and smart control system to actuate a variable orifice mechanism which connects the airspring to the accumulator. The main objective is to obtain a linear model for this pneumatic suspension so as to use existing advanced linear control methodologies to ascertain the closed loop performance and robustness. The two control designs investigated are a robustified LQG and mixed sensitivity H∞ control. The controllers designed (H∞ in particular) are shown to provide good performance enhancement over open loop with regard to vibration isolation while guaranteeing a desired degree of robustness to modelling uncertainties.