State estimation in electro-hydraulic actuator using proportional integral observer

In this paper, state estimation of electro-hydraulic actuator is presented. Electro-hydraulic actuators are critical components for control of aerospace vehicles and other precision motion control applications. Proportional integral observer is used to estimate the states in this nonlinear system. The proposed approach utilizes the complete model of the system including the nonlinear dynamics. The PI observer uses the proportional and integral values of output estimation error. The integral term is used to compensate the estimation error of the nonlinear function. The observer performance is demonstrated with simulated results and is seen to be superior to a recently proposed approach.