Theory And Technology Of Heterogeneous Material Components Of CAD Modeling

The current manufacturing industry request a higher and higher performance requirements of products, the single-phase or homogeneous parts is difficult to meet the needs of the functionality or performance of the products. The concept of heterogeneous objects has been proposed in recent years, which refers to functional parts and the interior of the part contained by the variety of materials by the way of continuous or non-continuous distribution. This thesis focuses on the concurrent design of materials and structures of the CAD model for heterogeneous materials, and has a research on the algorithm of space micro-tetrahedral reconstruction. This provides an effective method for the integration of designing and manufacturing for heterogeneous objects, and lays a foundation for its further industrial application.Based on the color STL (a three-dimensional model data format) model in the rapid prototyping field, to use the point clouds defined by refining STL model grid nodes, so that obtains a rapid and precise geometric reconstruction process of heterogeneous objects to ensure the orderly storage of data. Concurrent design of geometry topology shape (monochrome STL surface model data) and the material structure (color information) for the aim of meeting the functional requirements of parts.The modeling method uses the concept of the material slice, and mappings the space point clouds to two-dimensional slice for defining the materials. Through building correspondence between the material slice and physical slice, make material slice defined can be directly digital processed by using the CMYK3D printing method. This lays a foundation for the CAD/CAM integration for heterogeneous objects.Due to the data processing and analysis problems of CAD models for heterogeneous objects, the major research is to process the reconstruction of space micro-tetrahedron based on the Delaunay algorithm, including the overall design process and data structure. Ultimately, therefore, to get a correct and complete model-building process.Based on a integral three-dimensional printing system and the color STL model output from Magics RP software, to establish a corresponding relation between molding material and the micro-sprinkler in each layer. Indeed, this makes the digital control for the nozzle ejection came true. Proposing concurrent designing and manufacturing methods for Heterogeneous objects which based on the droplet injection technology and rapid prototyping technology. It is provides a possible means for the production of heterogeneous objects for the characteristics of precise injection or accumulation by point to point. For the reason that this propose unify the materials preparation and manufacturing for heterogeneous objects, a new mode is setted for the integration of digital design and fast accurate manufacturing for heterogeneous objects.The test based on the development of molding system for heterogeneous objects shows that the modeling method can be effectively solve the material definitions for heterogeneous objects which contains a variety of materials. What’s more, the method has a flexible feature on defining irregular material distribution. Related data are analyzed and processed for the aim of implementing and verifying for modeling and molding of heterogeneous objects.Finally, the main work and innovation are summarized, and the further research work is proposed as well.