Research On Modeling Technique And Simulation For 3D Solid Of Parametric Thread

Contemporary mechanical manufacturing is transforming to intelligent, integrated and flexible advanced manufacturing mode. CAD/CAM is the pivotal technology of CIMS; with the development of modeling tools and computer science, and with the particular development of software and hardware technology for graphics, Simulation comes into being. The application of simulation to NC is an important research content of CAD/CAM/NC. The chief problem of CAD/CAM system is how to describe the geometry model of 3D solid. 3D solid of thread is composed of complex helicoid with parameters, which is familiar in manufacturing and a complex 3D solid model in CAD/CAM/NC.This dissertation mainly studies how to establish the geometry model for 3D solid of thread. In this dissertation, the geometry model for 3D solid of thread is established based on turning machining progress of thread. Boundaries of thread are studied, and the external characters of thread are described. The mathematics model of 3D thread is established. The application range of expressions is confirmed, which ensures the exact selection of some points in the boundaries.OpenGL is applied as the developing platform to test the preciseness and availability of thread 3D geometry model. A method of thread geometry feature modeling is presented, which is based on Triangle Mesh. This kind of method can be used to establish other complex curved surfaces.Furthermore, in this dissertation the changing of thread under the conditions of different parameters is studied, consequently the thread's mesh and solid feature modeling has been implemented.A method is introduced to establish the operation scene, which can be used to establish operation environment and virtual manufacture.