New design of one motor driven under actuated humanoid hand

In this paper a new design of a humanoid hand with five fingers is presented. This hand is designed to carry out most complex and difficult manipulations. The designed hand may be used either as prosthetic device or as humanoid robot end effector´s. For these two applications, the shape, the weight and the energy consumption are important criteria to be taken into account in the design process. The reduction of actuators number decreases considerably the energy consumption and simplifies the control process. To satisfy this requirement, the proposed hand is an under- actuated mechanism having a total number of 15 degrees of freedom (DOF) and driven by only one motor. Each finger has 3 DOF for phalanxes flexion-extension movement. These flexion- extension movements of the five fingers are independents. They are driven by one motor and a binary mechanism allowing the selection of which phalanx is able to move or not. Simulation results showing a high capability of manipulating are given. The preliminary design of the adopted mechanism is also presented.