Dynamic Geometric Simulation For Selective Laser Sintering Process

This thesis was based on Selective Laser Sintering (SLS for short) process, developed a geometric simulation platform for SLS process by utilizing Visual C++ in Windows. The platform truly realized the SLS process geometric simulation and can be used to explore and validate the planning of scanning path.In the development of this simulation platform, the software Pro/E which is very common used in machinery is chosen to be as 3D modeling of the SLS equipment, and to establish a better virtual machining environment. Then the models are transformed into OpenGL to be displayed and controlled. By this way, the modeling time is shortened, the calculation is simplified and the reality of the SLS equipment is ensured.In the thesis, the laser scanning path is discussed and planned. Part to be sintered is drew in AutoCAD, and kept as a DXF file. By reading from the DXF file, the geometrical information of part profile is gained. Taking the FASS(space-filling, self-avoiding, simple and self-similar) fractal curve as laser scanning path, then its intersection with the contour profile of the part will be found. By using a trimming rule, an intersection algorithm was developed to fill an arbitrary profile with fractal curves. According the node coordinates, the laser scanning path is under control by programming.Finally, the 3D models of the equipment are displayed by utilizing the OpenGL light, color and material. Adopting OpenGL double buffer technology and translation, rotation order, combined with the Timer of windows, the dynamic geometric simulation of SLS process is realized. In the simulation process, scanning parameters can be changed and controlled in real-time.This platform possesses a good interaction and real-time performance. And in the meantime, its reality and the ability of transfer are also very good. Not only can it save resources, but also can be used to verify results of theoretical research and teaching demonstration. It has important theoretical and practical significance for the research of SLS process.