Research On Path And Velocity Look-ahead Algorithms For NC System With High Speed Machining Of Continuous Micro Segments

NC technology is the key of NC machining and the foundation for realizing automation of manufacturing industry.It is also the core technology of Chinese strategy that strengthen the country through manufacturing.Numerical control system is an important part of numerical control technology.The path and speed planning algorithm is the key to realize the motion control function of the CNC system.Based on the actual research projects and the existing technology,this paper carried out theoretical and experimental research on the turning point transition,acceleration/deceleration control and the speed look-ahead planning technology.Firstly,this paper briefly introduces the development status and composition of CNC system.It puts forward the research status and existing problems of CNC system in the path and speed planning process.Based on these problems,the research content of this paper is clarified.Besides,several methods of turning point transition are introduced.Based on these ways,the turning point transition based on the line segment and circle is put forward and the contour error,speed,acceleration and jerk constraint model at the turning point is given.Then,several acceleration/deceleration control algorithms in the NC machining process are introduced and compared.On this bais,this paper gives a detailed introduction to the S acceleration/deceleration algorithm.Then the problem of excessive calculation in the calculation of S acceleration/deceleration control is put forward and the solution of Newton iteration is given.On this baisi,this paper studies the speed look-ahead planning technology of the numerical control system.The speed look-ahead planning adopts the backtracking method.In the S acceleration/deceleration speed look-ahead planning,the speed look-ahead planning structure of the forward backtracking and backward adjustment is adopted to realize the smooth speed transition at the turning point.By presetting the maximum number of prospective segments,the overall processing efficiency can be improved as much as possible while ensuring real-time performance.Finally,this paper introduces the CNC numerical control device for running the path and speed planning algorithm.Then the specific application method of the path and planning algorithm in the system is illustrated and the corresponding experiments are done.The experiment verifies that the algorithm of this paper can improve the working efficiency under the premise of stability guarantee.