|
Abstract: The
asymmetric cylinder electro-hydraulic servo system is widely applied to
the hydraulically driven 6-DOF motion simulator used as actuator at
present, and its controller design is also noticeable. Firstly, a
general nonlinear model of the asymmetric cylinder actuator controlled
by servo-valve is derived. Then a cascade load pressure control
strategy, which gives the hydraulic actuator the character of a force
generator, is presented. So this establishes a basis for realizing the
hierarchical control of the motion simulator. Taking account of the
model uncertainties and external disturbances, the sliding mode control
scheme is used to the design of the outer-loop stabilized controller in
the actuator level which realizes the stabilization of the hydraulic
actuator and the disturbance rejection. Finally, a state feedback
controller is designed to compare with the sliding mode-cascade load
pressure controller. Simulation results indicate the control strategy
presented in this paper is effective and reasonable.
Key
words: 6-DOF
motion simulator Cascade load pressure control strategy
Asymmetric cylinder electro-hydraulic servo Sliding mode control
CLC No: TP137
Received 20040105, received in revised form
20020040410
|