Research On Numerical Control Turning Simulation Algorithm Based On Feature Modeling

The NC machining process is driven by NC program.But the programming of NC program is error-prone,and the error rate rises while the complexities of the components and the processing technic increase.In order to effectively verify the correctness of the NC program,the NC machining simulation technology is investigated.And the simulation algorithm is the key technology in it.In this paper,taking NC turning as an object,a numerical control turning simulation system is constructed by the GLScene in the Delphi development environment.Structural model of the system is established with sub-modules,then the function of each module is analyzed and designed in detail.Finally,the cutting algorithm of the system is studied.At first,in order to solve the NC machine problems of vivid types,complex structures,and less flexibility in static modeling,the dynamic modeling method of NC machines and tools library based on object-oriented technology is proposed.According to the structures of the machine and tool,a corresponding structure description file is established,and then a specific machine model and tool model is dynamically generated respectively.This method has more flexibility than static modeling,improves the modeling ability of the simulation environment,and makes the establishment of the body model independent of its structural complexity.Secondly,aiming at the disadvantages of large amount of data and poor authenticity for geometry modeling,the method of feature modeling is used to build the workpiece model.Features are analyzed and feature library is created for components,then parameters are descripted and model is built with discrete modeling methods based on triangle for basic features.And the modeling speed increases by using basic features.Finally,aiming at the problems of low accuracy and poor real-time performance in NC simulation system,a NC turning simulation algorithm based on feature modeling is proposed in this paper.The feature composition of workpieces is changed by feature operation,and then the shape is changed for components.The material removal of the blank during the cutting process is simulated.Complex Boolean operations could be avoided and the simulation accuracy and speed could be improved.