Optimization of Myoelectric Elbow Prosthesis Transmission

Limb prosthesis can be cosmetic or functional and latter active or passive. The active prosthetic arms can be body powered or have external source of power. Myoelectric elbows can profitably substitute the passive ones, with patient willing, only if they can guarantee: durability, low noise, adequate torque, low power consumption, low weight, easy motion control and natural movements. Most of these goals can be achieved by good electro-mechanical design. Currently two manufacturers share out most of the myoelectric elbows market but a few other producers are present and contributes to the improvement of the active prosthetic arm design. The evolution of the project of an Italian artificial elbow during the last ten years is shown and four different prostheses are compared in order to draw attention to the most critical aspects of the prosthetic design. The kinematic analysis of each device is described, highlighting the mechanical efficiency. A great amount of founds have been recently injected into this research area with the aim to design very sophisticated prosthetic upper limbs. Up to now no commercial products have been produced yet and only very few prototypes have been shown, but they are very promising for the future.