The Stress Analysis Of Prosthetic Socket And Computer Aided Design

The design of prosthetic socket is the most important part in prosthetic design and the quality of the socket directly influences the final product rate of the prosthetic. In order to improve the design of the socket, it needs to analysis the stress distribution of the prosthetic socket and learn the potential biomechanical relationship of the prosthetic/socket interface.In this paper, taken quadrilateral socket as an example it is introduced the main function of the prosthetic in socket/residual limb system, analyzed the design theory of different wall of the prosthetic socket. It is discussed the relationship of the trans-formal prosthetic and the movement of the body weight and pointed out the main supporting area of the body in different phase of gait cycle. The stresses are measured on the residual limb/prosthetic socket interface with the advanced stress analysis instrument. By the analysis of the data, it is concluded the stress distribution while the subject are standing and during walking on different phase of gait cycle. The stabilization of the medial-lateral and anterior-posterior are analyzed. The actual measurement results are compared with theory analysis. It is pointed out the same and different point of these two methods and analyzed the possible reason of the different. The simplified mathematical model of the prosthetic socket/residual limb system has been developed to analysis the stress on the residual limb. With this model it is analyzed the calculation method of the pre-pressure, average pressure and shear stress. It is discussed the support action of friction in stress distribution of the residual limb with an actual example. At the end of the paper it is introduced the basic theory of the finite element analysis method and the parameter acquirement method and trial process when using this method in socket/residual lirnb system. The merit and aim of applying this method are expressed in detail. By comparing the actual result with the finite element result, the effectiveness of the method is testified and it is showed that it has great meaning to applying this method in residual limb/prosthetic socket stress analysis.