Adaptive output feedback control of an electro-hydraulic system

In this paper, an advanced nonlinear method - adaptive output feedback (AOF) controller - is presented for position tracking control problem of a pump-controlled Electro Hydraulic System (EHS). The system uncertainties including uncertain parameters and external disturbances are covered by an adaptive law while all nonlinearities are compensated by a modified output-feedback techniques. For supplying necessary information to the controller, mathematical model of the EHS is derived in which a view of certain, an uncertain and nonlinear terms is clearly represented. The control input is then synthesized by incorporating the adaptive law with the control algorithm based on Lyapunov derivatives. Finally, effectiveness of the proposed controller is successfully verified through simulation and experimental results of different testing conditions.