The sensing subsystems and force control of the AMADEUS dextrous underwater gripper

This paper presents the design of the fingertip sensing subsystem constructed for use in a dextrous underwater gripper. Two distinct types of sensor were developed specifically for this application: a fingertip force sensor and a slip sensor. The force sensor is used to determine the force exerted by the gripper on the target object, while the slip sensor is used to detect the occurrence of slippage between the fingertip and the target. The force sensor is a simple robust device based on strain gauge technology and is incorporated on an artificial finger tip mounted at the extremity of the gripper finger. The slip sensor is an extremely small piezoelectric-based device capable of being shaped to suit the curvature of the fingertip. Closed loop control requires that identification of the manipulator dynamics be established, and these are presented along with the first results for closed loop control