Motion Controller System Software Design And The Study Of Motionsmoothing Processing

In recent years, as the market for the growing demand for motion controller, the users'functional requilements of the motion controller are more diversification.It has important practical value and significance to research and develop the motion controller of open framework. Motion controllers based on DSP+FPGA are becoming the main trend of open–architecture motion controller because DSP has the advantage of super-high-speed real-time processing capabilities and abundant peripherals and FPGA has the advantage of hardware logic control performance.The paper's hardware platform is based on the motion controller of DSP+FPGA. It introduces the hardware structure and main registers,and designs and develops the system software based on hardware resources of the motion controller. Adopting the idea of hierarchical and modular design, the system software is divided into four layer: the application layer,functional layer and the hardware driver layer. The application layer belongs to the upper software,and functional layer and the hardware driver layer belong to the next-bit software.The paper designs detailedly the main program of system ,the communications of host computer and the next-bit computer as well as the library functions.The paper achieves the key technologies of motion control, including the speed control,interpolation algorithms and position servo control. In the speed control, such as the article analyzes and compares the postulates and characteristics of two acc/dec control curves_S shape curve and trapezia curve,and programm of two kinds of acc/dec control curve.In the study of interpolation algorithms,data sampling interpolation algorithms is adopted to achieve Linear and circular interpolation algorithm.In arc end-point distinguishing,a new method of end-point discrimination is used,which is angle end-point distinguishing.In the position servo control algorithm, the typical PID algorithm is adopted to achieve the smooth operation of the system.As the growing demand for high-motion controller features, in addition to the basic linear and circular interpolation functions, complex curve interpolation is also essential.The paper describes detailed the basic theory of complex curve( NURBS), and introduces the NURBS curve interpolation algorithm.Besides this, the error is calculated to reduce the interpolation error in the NURBS curve interpolation process, and the paper program of NURBS curve interpolation algorithm.Considering software reliability and code running speed,soft development platform and code optimization method is discussed. Individual modules and overall system is debug so that the motion controller can work well with anticipated function and performance.Generally,the motion controller used in CNC adopts more of the position servo control,but the article adds a velocity loop control based on the position servo control to increase the accuracy and speed of the motion controller.