Controlling Vibration in Remote Manipulators

Robotic manipulators for use in space have flexible structures and as a result have special control problems. These manipulators change their vibrational characteristics as they change in orientation. The Space Shuttle Remote Manipulator System (RMS) was chosen as a typical system and experiments were performed using the Draper Laboratory software model of the arm (DRS). First, the workspace of the manipulator was characterized in terms of the robot’s first two modes of vibration. Next, some feedforward experiments were performed on the computer model to show the promise of vibration reduction using feedforward control.