Table 1: Characteristics of existing space end effectors and differences with the requirements of the newly developed one.

Name	Picture	Characteristics	Differences of the newly designed end effector
Robonaut hand [4]		A highly anthropomorphic human scale robot hand designed for space based operations. This five finger hand combined with its integrated wrist and forearm has fourteen independent degrees of freedom.	It will not be anthropomorphic, since power grasp, rather than manipulation is the main task.
JAXA THK hand [12]		It is properly an anthropomorphic hand which has dexterity and could be exchanged from its wrist.	It will not be anthropomorphic, since power grasp, rather than manipulation is the main task.
JAXA REXJ hand [12]		The REXJ hand satisfies specific tasks, such as locomotion assured by the tether-bases walking. It must be sufficient powerful so that the hand can convey a tether's hook.	It must be able to adapt not only to cables, but to cylindrical and prismatic shapes.
DEOS end effector [13]		It is focused on grasping an uncooperative tumbling target. It has 3 rigid fingers actuated by only one motor (ILM 70) providing a maximum torque of 3 Nm.	It must be able to adapt to different shapes, and provide larger grasping forces.
SARAH [9]		It is a self adaptive and reconfigurable robotic hand for space application. It has three fingers and each of the fingers has three phalanges. The hand has ten dofs, actuated by two motors, i.e., one for opening/closing of the fingers and one for orienting the fingers.	It must have only one actuator and a simplified design.