Research On The Contour Precision Control Technology Based On CNC System

Accompany with the development of modern manufacturing industry CNC manufacturing technology has been widely applied and is upgrading all the time.As the brain of the CNC manufacturing technology,accuracy,flexibility and versatility make its industry position more stable day by day.And therefore CNC manufacturing technology has more stringent requirements.Trajectory tracking ability is one of the key technologies of CNC system that is developing quickly.At present CNC system mostly use uniaxial independent control method.But it would cause secondary deviation which would direct impact on the machining accuracy.In order to solve this problem,this paper uses the contour error control method.On the one hand based on the optimum circular contour approximation method a novel estimation model for estimating the contour errors in real-time is proposed and implemented which overcomes difficulties the approximate calculation of contour error process is too complex that big calculated amount is needed for free-form curve.In this method,feedback of the feed systems and interpolation data of the CNC are read and recorded to calculate the contour error vector in real time but not depends on tracking error.On the other hand double fuzzy and variable region adaptive control algorithm is combined to be used in biaxial NC systems after the contour error estimation model is established.Finally a new motion control board A_V2 is designed and the typical contour were processed by the test machine tool that equips A_V2 to do some comparison experiments in order to verify the proposed approach.The results of comparison experiments show that the double fuzzy control with variable region for contouring control based on the optimum circular contour approximation method could obtain satisfactory contour precision.The research on contour control of CNC manufacturing technology meets the requirement of high speed and precision processing.Also,this will inevitably promote the scientific research on CNC more significantly and practically.