The present invention is a
wrist mechanism and a method for making robotic devices in which the transmission of motion, force and / or torque around a
revolute joint can be accomplished without
coupling. This construction allows mounting the actuators on the base or lower elements of a mechanism, so that only linkage elements move the end-
effector. Thus reducing
inertia of the moving elements and increasing performance of the device. The decoupled motion of the end-
effector or links is achieved by routing their transmission cables around idler pulleys placed parallel to the
joint rotation axis on an optimal position such any stretch on the
transmission cable is minimized. In particular, this construction can be use for robotic surgical tools that have two independently driven jaws, decoupled and orthogonal from its articulating
wrist. This device may be used in grasping,
cutting, suturing or alike operations.