ABSTRACT
Some hydraulic parametric uncertainties exist in electro-hydraulic systems. These uncertainties include uncertain linear/nonlinear parameter and uncertain nonlinearity [17], which are caused by unknown viscous damping, load stiffness, variations in control fluid volumes, physical characteristics of valve, bulk modulus, and oil temperature variations [42]. If these uncertainties are not addressed in the control design, the dynamic and steady performance of EHS will be degraded and the robustness of the designed controller will also be reduced. In this chapter, the robust control method of EHS is proposed to handle the parametric uncertainties and compensate their negative effect in real engineering [20]. Thus, the dynamic and steady behaviors are obviously improved, especially the largely unknown load disturbances emerging in the electro-hydraulic actuator.
