Raptor Prosthetic Hand

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This prosthetic hand is a terminal device, functioning as a voluntary closing device with the option to reverse the cable system for voluntary opening. The prototype uses paracord and shock-cord as tensioning cables and springs, respectively, although rubber bands and fishing line could be used for a lighter method. Finger rotation is at one point per finger, reducing print flaws and improving durability. Smooth objects may require rubber sheathing, but the pinky finger can hold items like soda cans. A hook between where middle fingers would be allows for carrying bags and grasping with a pinch motion. Writing implements can be held using either the thumb or all fingers. Each finger can be independently actuated, but as this is a terminal device, all fingers are positioned and secured with one cable actuation. Compliance in the hand can be maintained by using strong elastic as the interface to the actuation cable. The prosthetic attachment bolt is placed inside the print halfway through, encasing it securely within the palm. A print takes 8.5 hours, producing 4 printed parts with 3 individual designs, weighing 0.49 LB in total.