Aspects of the design and development of a subsea dextrous grasping system

This paper considers aspects of a 3 finger dextrous grasping system. Its aim is to provide low force grasping and manipulation of compliant or rigid objects in the ocean up to 150 mm diameter and 5 kg mass. The gripper fingers are constructed using a robust flexible-motion generation mechanism that allows passively compliant, omni-directional finger movements with no joints. The fingertips are equipped with a tactile sensor measuring magnitude and direction of applied force, independent of ambient pressure and temperature. Supervisory control will be used as an operator assistant, to achieve automated grasping with error recovery. Results are described for open loop manipulation and assembly and for calibration of the force sensor. The architecture of the automated grasp planning subsystem is discussed, with examples of its operation