Patent attributes
In a robot of an elbow joint of a humanoid robot, a first main link and a second main link are connected through a first movable link and a second movable link, and the two movable links are arranged to cross. Specifically, in a quadrangle whose apices are formed by rotation axes A, B, C and D, when assuming that rotation axes diagonally opposed to each other are A and C, and B and D, the rotation axes A and C are connected through the first movable link and the rotation axes B and D are connected through the second movable link in such a manner that the first and second movable links are disposed to cross, and that the rotation axis A is driven by the actuator to drive the first movable link, such that the first and second main links are displaced relative to each other. In addition, the first movable link is rotatably connected to a first plate and a second plate through the rotation axis A, while the second movable link is rotatably connected to the first plate through the rotation axis B. With this, it becomes possible to increase the overall driven angle of the joint relative to the input, expand the range of motion of the joint in the bending direction, and also raise the critical value of the driven speed (i.e., rotational speed).