Feedback linearization for acceleration control of electrohydraulic actuators

Abstract

Accurate control of acceleration is important in several fields: prime examples are flight simulator motion and vehicle active suspensions. In both these applications hydraulic actuation is normally found to be most appropriate, despite certain non-linear characteristics. This paper describes a feedback linearization technique for controlling the acceleration of electrohydraulic actuators, compensating for the main non-linear characteristics of the valve and cylinder. Two versions are simulated and compared with conventional linear controllers. The first version requires velocity, acceleration and pressure feedback; the second dispenses with the need for acceleration measurements. Significant performance improvements are achieved over conventional methods.