Vibration Suppression Method Based on PI Fuzzy Controller Containing Disturbance Observe for Dual-flexible Manipulator with an Axially Translating Arm

摘要

A dual-flexible manipulator with an axially translating arm is composed of a motor, a flexible joint, and a flexible load that can be telescopic. The friction torque at the motor, the time-varying characteristics of load parameters, as well as the flexibility of joints and loads will cause the vibration of the manipulator. Transverse vibration will affect the movement accuracy of the end-effector. In this paper, a fuzzy adaptive PI control strategy containing disturbance observers (DOB) is used to reduce the fluctuation of the servo system's output speed, thereby suppressing the vibration of the manipulator. Firstly, the dynamical model of the dual-flexible manipulator considering the friction torque is established. Then, the low-pass filter in the DOB is designed, and the PI controller parameters are adjusted in real-time by the fuzzy adaptive control strategy. Finally, the numerical simulation analysis and experiments of the dual-flexible manipulator are carried out. The simulation and experimental results show that; 1) The DOB can effectively eliminate the influence of friction torque; 2) The control strategy can reduce the output speed error. Therefore, the control strategy proposed in this paper can effectively reduce the vibration of the dual-flexible manipulator with an axially translating arm to improve the movement accuracy of the end-effector.