Multi-directional stabilization of a large-scale robotic manipulator

In this paper, the application of a piezoelectric stack actuator for vibration control in a large-scale robotic manipulator, called the macro manipulator, is studied. The structural flexibility of the system includes deflection and torsional vibration modes. The vibration modes are detected using an appropriate sensor attachment. A nominal transfer function matrix between the input signals of the actuators and the output voltages of the sensors is obtained. A closed-loop controller based on the obtained model is designed. Because of the presence of different vibrational modes and model uncertainties resulting from manipulator motion as well as its varying payloads, an H_infin robust controller is utilized and experimental results are presented