Position/force control of an arm/gripper system for space manipulation

In advanced robotics applications, as those foreseen in space, some degree of dexterity and autonomy is necessary in order execute tasks in unstructured environments. For this purpose besides the kinematic configuration of the device other basic issues are the sensorial equipment and proper control strategies. The paper presents an experimental activity for the validation of a robotic gripper for space applications. In particular the project foresees the compatibility of the gripper with the EUROPA arm, developed by ASI and Tecnospazio. The key points of the gripper design are the wide working space compared with its physical dimensions and the capability to deal with free-flying objects in zero-gravity conditions. This capability is achieved by using proximity and force/torque sensors and by properly controlling and coordinating the gripper and the carrying arm. After a brief illustration of the main features of the gripper, the experimental activity is presented and the results achieved so far are discussed.