Improving the Composite Materials for Bi Lateral Prosthesis with Below Knee Amputation

Abstract

This study used the tensile and fatigue test to find the properties of composite material used to fabricate a prosthetic socket with below knee amputation using an excluding air technique. The composite materials consisted of eight layers of carbon-fiber for first socket and eight layers of perlon for second socket of below knee amputation. This study was conducted on a patient have 45years old of height 164cm and weight95kg were measured, and the results showed that the ultimate stress (Ϭult) and yield stress (Ϭy) for eight layers of perlon was39 MPa and 36 MPa, while for eight layers of carbon-fiber was 135 MPa and 121 MPa. The fatigue limit for eight layers of perlon was 15 MPa and for eight layers of carbon-fiber was 90 MPa. The value of pressure on the internal wall of the prosthetic socket was measured by F-socket sensor between stump and socket for four position; this data is anterior =210kPa, lateral=313kPa, posterior=225kPa and medial=180kPa. From mechanical properties and ANSYS workbench 14.5software, the safety factor for below knee socket with eight layers of carbon-fiber is (1.35) which is acceptable for socket design. The safety factor for below knee socket with eight layers of perlon is (0.22) which is failure.