Papers by Keyword: Virtual Numerical Control

Abstract: After the virtual NC real-time machining process control technology is studied, we design the NC code interpreter using the pipeline control method of overlapped resources in this paper. In order to improve the availability of interpreter, the design adopts the function pointer array and expression evaluation algorithm. By using two methods, the scalability is enhanced. Also the versatility is improved by using keywords information table to some extent. The system achieves a straight line and arc of the trajectory interpolation by the digital sampling algorithm and makes the efficiency improved by using RCS communication mechanism, windows thread and timing mechanism.

Abstract: Joint modeling of exponentially fitting and least square method was proposed for key technical problems on milling temperature and heat deformation of tool in virtual numerical control (NC) simulation. Mathematic model of surface temperature and its influencing factors based on ball-end mill was established. Correlation coefficients of model are over 0.8, and the errors comparing with the experimental ones are within 10%, which shows that the model meets precision requirement, and fitting effect is good. By this model a mathematical model of the ball-milling cutter’s thermal deformation was established, and the relative error is small by comparing with test values, which proves that this model has high calculation precision and practical meaning. A simulation prediction system of milling temperature and ball-end mill’s heat deformation in virtual NC was developed based on above mentioned models, which can provide theoretical basis for machining error prediction, optimizing milling parameters and improving machining quality.

Abstract: Virtual numerical control milling simulation system, based on UG, is studied oriented to low utilization of NC machines. A virtual machine tools library, standard fixture library and visual machine tool processing environment were established by the second development techniques of UG and VC++. Through the example of XH715 NC machine center, tool path and motion of miller were simulated separately; at last processing scheme was evaluated and optimized. The experimental results show this system possesses good utility, and the utilization of machine tools could thus be improved.

Abstract: A parameter equation based on cutting edge of ball-end mill is set up by analyzing the parameters of ball-end mill influence the milling force in virtual NC milling process. The relationship among elemental cutting force, instantaneous radial chip thickness and cutting edge length is analyzed, and the dynamic milling force of ball-end mill at arbitrary feed direction is established. The milling force parameter model by quadratic regression equation in different cutting conditions is built. Through experiments in NC machining center and using orthogonal combination and principal components analysis, the regression coefficients are calculated. The correctness of milling force model is testified by experiments. All these can provide theoretical basis for physics modeling and simulation of virtual numerical control milling.