Design Of A Prosthesis Socket With Pressure-adjustable Interface

Prosthesis socket is a kind of human-machine interface without whichthe prosthetic hand cannot work functionally. A functional prosthesissocket should be safely wearable and be able to transfer force or movementbetween weight-bearing stump and prosthesis, which means high fidelityand comfort. This requires the human-machine interface in the socket to beboth flexible and rigid, which is apparently contradictory in its design. Soto build a high fidelity and comfort prosthesis socket, rigid property of theinterface and the load ability of soft tissue should be both considered. Toachieve it, this paper proposed a new design concept to apply the clampingpressure on stump only in needs. To realize this concept, apressure-adjustable chamber with negative stiffness was designed to formpressure units in sockets. The feasibility of the chamber in meeting therapid switching the interface’s mechanical property from soft to hard wastheoretically studied. Then a physical model of prosthesis socket with fourpressure-adjustable chambers was fabricated for the experimentalconfirmation of the conceptual design. Promising results were obtainedboth in its pressure-adjustability and response speed. Conclusion can beleaded that Prosthesis Socket with Pressure-adjustable Interface has bothhigh function transitivity and great comfort.