| Summary: | 碩士 === 國立成功大學 === 機械工程學系 === 89 === During the design and fabricating processes of a prosthesis socket, in order to avoid the damage on the pressure-relief areas of the limb, such as tibia, the positive mold of the residual limb that is used to make the socket should be modified. Using the technique of reverse engineering to design prosthesis socket, a three-dimension laser scanning measuring is used to obtain the shape information of the residual limb; a computer-aided system is employed to reconstruct a CAD surface model; the CAD model is then used to modify the shape according to the prosthetist requirement. The study focused on developing a method of modifying the CAD surface model to meet the design requirement, and that allows a prosthetist changing the shape of the CAD surface model only providing the required information in a simple sequence.
The proposed algorithm used the theory of B-spline curve and the method of knot insertion to add a new control point corresponding to the central point of the region to be modified. Once a region is selected and required change has been determined, the newly-built control point is then moved to an appropriate position in normal direction to meet the design change under an accepted tolerance. All the corresponding control points of the selected region are simultaneously moved under the restriction of keeping all the boundaries unchanged. A case study has verified the algorithm that can meet the required design change for prosthetic socket.
|
|---|
