Optimization Design Of A Prosthetic Hand Socket With Partition Constant-force Compression

Prosthetic hand socket plays an important role between a prosthetic hand and residual limb as a connection bridge in the process of realizing the prosthetic hand's function.In order to remedy the design shortcomings of pressure-adjusting prosthesis socket from Ganyun,based on the prosthesis interface design requirement of function transfer and interface safety,according to design concept of time-shared and load-bearing,we put forward a prosthetic hand design with partition diversity and constantforce stability characteristics.Through the theory exploration and comparison between the original design scheme and the optimization design scheme,the feasibility and rationality of optimization scheme is confirmed.On the basis of the original negative-pressure driving design,we proposed the design scheme of constant-force extrusion unit,which realizes the constant-force by the positive and negative stiffness paralleling.We analyzed and calculated the design parameters of extrusion unit with the mathematical model method.Then we optimized the parameters with simulation method and found the connection between the element parameters and its negative-stiffness characteristic.The stable constantforce characteristic of the extrusion unit is verified after the pressing experiment.By analyzing and exploring the extrusion unit number and distribution of prosthetic hand socket,we identified the advantage of double-row extrusion block design for time-sharing and load-bearing controlling.According to the mechanical analysis of three kinds of basic experimental paradigm,we determined corresponding compression state of different extrusion units under different movement modes.Through the miniaturization of constant-force extrusion units and optimization of prosthetic socket,finally we completed the prosthetic hand socket with partition constant-force compression.Through switching response experiments,slipping tests and indentation experiments,we verified the function transfer and interface safety characteristics of optimization design.Compared the optimization design with the original design,the extrusion area is more diversified,switching process is more stable,and the pressure of interface is lower.The optimization scheme significantly improved function transfer and interface safety characteristics of prosthetic hand socket.