e-Nable ratchet force amp pulley concept v1.1

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The concept for e-Nable prosthetic hands aims to provide more force for individuals with weaker wrists that have limited bending/travel range capabilities. This is achieved through the integration of a pair of pulleys combined with a ratcheting mechanism, allowing for a gradual increase in grip strength as the wrist bends multiple times. The pulleys operate on a single axle, each featuring a different diameter. By placing cables across both pulleys, directed at opposing angles, users can harness more force by pulling one cable and leveraging the smaller hub's increased tension. Cable diameters of 0.4 mm are sufficient for passage through holes; however, slightly larger diameters may be necessary if using thicker cables. This system enables users to duplicate force with repeated bending movements or achieve a 1:3 strength ratio, allowing them to grip completely even after minimal bending. The prosthetic's pink component serves as the fixed part housing the rotating pulleys, which require a 3mm bolt axle for rotation. A release mechanism has yet to be developed but is considered relatively straightforward. Testing and adjusting spacings/sizes are also necessary steps in this design process.