Research And Development Of Geometric Simulation System Of CNC Machining Process

Virtual manufacturing technology, compared with traditional manufacturing methods, have a high level of system integration, support for distributed collaboration and agile manufacturing characteristics, and the manufacturing process is completed entirely in the computer, so it greatly reduces the product development cycle and improve production efficiency. CNC machining process geometr ic simulation is the key underlying technologies of virtual manufacturing technology, applications of this technology reduces the time from product design to manufacture and reduce production costs, so it has been more and more widespread application in CNC machining industry. Research on NC machining process geometr ic simulation has a positive significance to enhance our manufacturing technology. The main work of this paper is:1. Design the overall structure of the simulation system based on the analysis of the requirements of the system. First analysis the design requirements 、 functional requirements、input and output requirements, then design the overall functional structure and the input and output flow chart, and design the interactive interface. The simulation system is divided into six modules. Briefly introduce the design and workflow of NC code analysis module, DNC communications module, collision detection module interference, and accuracy verification module. Describes the simulation system development platform and OpenGL graphics technology, and in the VS2010 environment build a simulation system development environment based on OpenGL technology.2. Establish the geometric model and motion model of the virtual machine. Make the models in CAD software, convert them to STL files and read them with the CAD interface. Analysis the assembling and constrain relationship of components of an AC type 5-axis machine, assemble all the parts. Analysis the kinematic chain of the machine, using linear interpolation algorithm based on time division to calculate motion of each axis, in order to achieve motion simulation of the machine.3. Study how to convert workpiece and the tool to Dexel structure. Describes a method for constructing STL model into Dexel model and Dexel data structure. Propose an accelerated algorithm to construct the Dexel structure of tool based on bounding box of the shadow of tool, analysis six cases of Boolean operation and design the workflow. Reconstruct the workpiece by triangular facets after Boolean operation in the tool path interpolation points. Dynamically display the cutting process through dual- thread technology and OpenGL double buffering technology and give an example of authentication.