Abstract
This invention provides an end-effector for robotic arms. In one embodiment, said adaptor comprises: a) a first housing having a center line; b) at least one rotational member with rotational axis perpendicular to said center line; c) a first pair of actuation wires; wherein said first pair of actuation wires are connected to said at least one rotational member to actuate rotation with a pull-pull mechanism whereby tension and displacement in each wire of said first pair of actuation wires are same but direction is different.