Developments for an oleo-pneumatic active suspension

The paper describes an oleo-pneumatic active suspension which has been developed using a linear multivariable controller. In order to optimise the performance of the system it has been necessary to address the nonlinearities of the system, such as those inherent in the gas spring, bump and rebound stops, dampers and flow control valves. A description is given of the nonlinearities and effects encountered under changing load, manoeuvre and ride inputs. Results are presented which demonstrate the benefits of using a nonlinear controller model within an adaptive control scheme.