A Glossary of Manipulation and Gripper Terms

The vocabulary that comes up constantly in any discussion of robot hands and grasping.

Basic terms

End effector: whatever's attached to the end of a robot arm to interact with the world — a gripper, hand, or specialized tool. Degrees of freedom (DoF): the number of independent ways a joint or mechanism can move. Payload: the maximum weight a gripper or arm is rated to hold reliably.

More specific terms

Underactuation: having fewer motors than degrees of freedom, relying on mechanical design for passive adaptability. Compliance: how much a gripper or joint yields to external force rather than resisting it rigidly. Grasp stability: how reliably a given grip holds an object under expected disturbances like movement or gravity. Slip detection: sensing the earliest signs that a held object is starting to move within the grip.