The robotic gripper was developed at NASA Goddard Space Flight Center as part of a robotic satellite servicing mission. The gripping device can be used to autonomously or remotely grasp and control an out-of-fuel or otherwise disabled satellite. Specifically, the gripper interfaces to the separation ring (marman ring) of the client spacecraft and when closed, is sufficient to constrain all six degrees of freedom of motion between the servicing spacecraft and the client. The jaws are designed with a conformable geometry that allows the same gripper to interface to all spacecraft separation rings commonly used with Atlas V and Delta IV launch vehicles.
The gripper is located at the end of a robotic system consisting of a robotic arm equipped with a tool drive or end effector comprising the input actuator to the gripper as well as the structural, power, and data link between the gripper and the robotic arm. In a notional concept of operations, a servicer would approach the client in an autonomous rendezvous and capture (AR&C) maneuver. When the servicer's sensor suite confirms that the distance, orientation, and relative translational and angular rates with respect to the client are within an acceptable range, the servicer enables the grasping sequence, where the robotic arm, equipped with gripper, extends forward to the client. When the gripper/servicer sensors indicate that the client marman ring is sufficiently within the capture range of the gripper, a trigger signal is sent to the robot control system that commands the end effector to drive the mechanism of the gripper and affect closure around the marman ring.
The gripper consists of a pair of jaws that is driven by an internal transmission. The transmission receives input torque from the end effector and converts the torque to appropriate motion of the jaws.