Research & Realization Of Modelling And Deforming Technology For Shoe-Last Based On Input Of 3D Scanning

Shoe-last is the essential mold in the entire shoe-making process, so to optimize the design of shoe-last for the entire shoe-making process is of great significance. In order to meet the needs of the shoe-last design, the paper has proposed that obtaining the digitized three dimensional model of shoe-last by the preprocessing for three-dimensional scan data of shoe-last, carrying on designs such as surfaces generated and deformation for the model, the data of shoe-last after the completion is exported to the rapid prototyping machine, and customizations of the shoe-last according to different needs are realized.The digitization of three-dimensional shoe-last model is the first step to achieve the three-dimensional shoe-last modeling. In this paper, the second chapter describes the capture, the model expression and the feature recognition of the shoe-last digitization model. Cloud data are obtained by three-dimensional scanning, and then the cloud data are converted into the triangle grid model using the Geomagic tool, and the datum are preserved in some format. Shoe-last CAD system gets the data file of scanning shoe-last, and obtains the scanning shoe-last model, which has the correct characteristic information through the feature recognition.The construction of three-dimensional model for shoe-last is the basis of designing shoe-last. The model of shoe-last being preprocessed, is made up of disordered data set of points that are connected by triangular mesh, which is not in favor of processing for shoe-last such as deforming and so on, so it is necessary to transform it into the three-dimensional model of shoe-last that is made up of regular mesh. In Chapter 3 of the paper, a modeling technology of three-dimensional shoe-last based on the section link is presented, and the entire process of model surface production is elaborated in detail, including the processes of the sub-surface-generation of three-dimensional shoe-last model, surface splicing, smoothing the surface, controlling the surface errors and so on. After modeling of shoe-last, not only the surface features of the original model can be maintained, but also the algorithm efficiency of shoe-last distortion processing can be enormously enhanced.Deformation of three-dimensional shoe-last model is crucial to the design of shoe-last. The fourth chapter elaborates three kinds of driving deformation technology for shoe-last that are separately based on the characteristic size, the template, and the sketch. The deformation of surface for shoe-last based on feature size driving is a method that carries on the parameterizations of the model-driven deformation by the extracted feature size. The shoe-last deformation of surface which is based on the template-driven carries on deformation by using the interpolation of the standard models. Deformation of the shoe-last surface based on the draft-drive is based on the constrain solution, and actuates the model deformation of shoe-last through dragging the control point.Based on the research content above, we have developed a Shoe-last CAD system. Chapter 5 of the paper introduces the development environment and the work flow of this system. The example of the research work above is given simultaneously.Finally, the prospect of the project research is forecast from the aspects of technology and application.