Study on Control Method for a Robotic Rotary Hydraulic Actuator

Abstract

Abstract. In this work, we proposed the control method for a robotic rotary hydraulic actuator. We have designed and fabricated some prototypes of rotary hydraulic actuators. Because of valve dead zone, load disturbance and variable hydraulic pressure, the simplex PID method can't meet the control complexity. In order to improve the servo accuracy, we proposed an adaptive control method. The valve dead zone is indentified by the output feedback of the rotary actuator; the load torque is considered as the random disturbance; the good control performance and robustness are obtained by adaptive function control according to the hydraulic pressure. In the future work, we will finish a 6-Dof robot arm equipped with the rotary hydraulic joints, and further test the dynamic characteristics of the rotary hydraulic actuator.