Research Of Key Technologies Of Physical Simulation Of NC Milling Machining

Physical simulation is a complicated research subject, including plenty of foundations, theory and experiments to study. It must solve in order to develop further in NC machining technology. Physical simulation research based on NC geometric simulation has an important meaning for improving machining efficiency and machining quality of workpiece.This dissertation integrates theory analysis with experiment research and makes further research on NC geometric simulation. The establish of the cutting forces model, cutter wear model, machining error predition and compensation, machining parameter optimization in the physical simulation fields are made more research on the basis of the above research contents. The main achievements are as follows:1. System structure of NC machining simulation by integrating NC geometric simulation with physical simulation is designed. System structure model based on simulation database is presented, by which realize effectively to integrate NC geometric simulation with physical simulation.2.In the NC geometric simulation and NC verification, a partial rendering algorithm is improved by using dynamic OOB(oriented bounding box). The NC verification algorithm named Z&N method and named N&N method is presented, Z&N method is involved in verification efficiency and N&N method lays a particular stress on verification effect.3. In the milling forces simulation model, the algorithm to identify the engaging cutting edges is proposed using Z-map simulation model in ball-end milling process. The expression of instantaneous chip thickness is discussed by analyzing the effect of cutter eccentricity and deflection. Then ball-end cutter milling forces simulation model is established on the basis of the relationship between milling forces and chip load. In the process of establishing model of ball-end cutter milling forces, the algorithm of determining cutter eccentricity parameters are presented to integrate the condition of single edge cutting. The cutter eccentricity parameters are decided by using the above algorithm in the process of calculating milling force coefficients according to the experiment data of milling force. Results of experiment show that the simulation algorithm is satisfying.4.The machining errors arised from the cutter deflection and tool wear are...