Electro-hydraulic servo-systems are widely employed in industrial applications such as robotic manipulators, active suspensions, precision machine tools and aerospace systems. They provide many advantages over electric motors, including high force to weight ratio, fast response time and compact size. However, precise control of electro-hydraulic systems, due to their inherent nonlinear characte...

1 Abstract—Utilizing model reference adaptive control approach and multiple Lyapunov functions method, we propose a switched adaptive controller for uncertain switched linear systems in control canonical form. These systems exist naturally in many practical applications, such as variable capacity hydraulic pump involving discrete changes that are specified by the valve position. We show that th...

Increasing demands in performance and quality make drive systems fundamental parts in the progressive automation of industrial process. The analysis and design of Mechatronics systems are often based on linear or linearized models which may not accurately represent the servo system characteristics when the system is subject to inputs of large amplitude. The impact of the nonlinearities of the d...

This paper studies the high performance robust motion control of electro-hydraulic servo-systems driven by double-rod hydraulic actuators. The dynamics of hydraulic systems are highly non-linear and the system may be subjected to nonsmooth and discontinuous non-linearities due to directional change of valve opening, friction and valve overlap. Aside from the non-linear nature of hydraulic dynam...

Abstract: Pitch Control plays a significant role for a large wind turbine. This study investigates a novel robust hydraulic pitch control system of a large wind turbine. The novel hydraulic pitch control system is driven by a novel high efficiency and high response hydraulic servo system. The pitch controller, designed by two degree-of-freedom (2-DOF) motion control with feedback linearization,...

In industrial applications, the dynamic characteristics of the servo-hydraulic system are always complex and highly nonlinear. Moreover, there are too many uncertainties in it; for example, the viscosity of oil, the bulk modulus, the oil volume, the system pressure, the wear and the cavitations. The loading conditions are usually rather unsteady, and the loading forces change in a wide range du...

The gimbal stabilization mechanism is used to provide the stability to an object mounted on the gimbal by isolating it from the base angular motion and vibration. The purpose of this paper is to present a model of control servo system for one axis gimbal mechanism using a cascade PID controller. The gimbal torque relationships are derived by taking into consideration the base angular motion. Th...

Electro-hydraulic servo pump control belongs to an electro-hydraulic coupling motion system, which involves the mutual penetration and integration of mechanical, hydraulic, electrical, control, other disciplines, as well time-varying, uncertain, multisource, multifield problems internal external excitation makes system have characteristics a complex model, strong coupling, nonlinearity, time-va...

The hydraulic servo control system, which is the important component of parallel robot, is a high order, nonlinear, dynamic asymmetry, parameter uncertain system, which seriously affect dynamic performance of robot, so it is very difficult to gain good performance with traditional control. Based on sliding mode variable structure control method combined with fuzzy control and adaptive control, ...