Adaptive Fuzzy Sliding-Mode Control for Direct Drive Electro-Hydraulic Servo Rotary Vane Steering Gear

Aiming at the rapidity control problem of direct drive electro-hydraulic (DDEH) servo rotary vane steering gear, a design method of adaptive fuzzy sliding mode control with friction torque dynamic compensation is presented. The friction torque dynamic compensation method is introduced to enhance the response of the system. The adaptive fuzzy controller is introduced to solve the problem of the uncertain parameter and external disturbances of the system, so the controller can be designed without accurate model. The adaptive law, which is derived of Lyapunov method, guarantees the stability of control system, reduces the high frequency chattering. The experimental results indicate that the control approach can decrease the tracking error, and the response time, movement accuracy and resistance to load disturbance of the system can be improved, the system has good performance in tracking, and unknown disturbance can also be greatly compensated.