Experimental study on slewing and sensor based active vibration control for flexible manipulator

When the manipulator is lightweight, especially for space application, the robotic systems are subject to high degree of flexible and encounter unavoidable mechanical vibration. The experimental setup of flexible manipulator was designed and built to verify the approach proposed for actively controlling the unwanted vibration. Control scheme consists of one AC servomotor actuator to drive the flexible link through harmonic gear speed reduction, and two sensors including piezoelectric ceramics (PZT) patch attached to the surfaces of the flexible link and an acceleration sensor fixed at the tip of the link were used as sensors. Two active vibration controllers including the reduced modal PD and PPF controller were investigated to suppress the unwanted vibration due to environmental stimulation, especially the undesirable oscillations caused by the motor torque during the hub slewing motion. The experimental results show that the vibration of the system is significantly suppressed, the adopted control methods are effective.