Research On Contour Control Based On X-Y Motor Platform

Multi-axis machine with high precision,high efficiency,and other characteristics,is widely used in high-performance contour processing.Quality of its products is related to multi-axis control system,drive,motion controller and many other factors,and contour motion controller is one of the key.Therefore,the study of contour motion control for high-performance contour machining has been a hot spot in recent years.In this paper,the contour error calculation model is studied and the corresponding global task coordinate system is established.Based on analysis of the sources of modeling errors the contour motion controller with good robustness is designed.Firstly,according to the definition of contour error,a new contour error formula is proposed on the base of analyzing the shortest distance formula of point to line,point to circle.At the same time,the tracking error of the expectation point is included in the contour control target.In accordance with the global orthogonal relationship between the contour error and the tracking error,a new task coordinate space,of which coordinate axis represents the contour error and the tracking error,is established.At the same time,contour control and tracking control is decoupled in the new coordinate system.Secondly,based on the analysis of the source and the range limit of modeling error,a simple adaptive robust controller(SARC)applied in the new system is designed.The robustness of the system is improved by establishing the error compensation mechanism.Considering the variability of model parameters,the strategy of parameter online estimation is added in SARC which constitute the composite adaptive robust controller(CARC).In the Matlab/Simulink environment,the contouring motion performance of controller,SARC and CARC,applied in the new coordinate system and local task coordinate system,are simulated and analyzed.Finally,according to the actual operation of the X-Y motor platform,the calculation of the coordinate transformation matrix is simplified.By calling the control function in the MPI database,the control code is written with C in Visual Studio2005.The performance of the contour motion controller designed in this paper is verified and compared with the traditional controller.The data collected by Motion Scope are exported and analyzed by Matlab.The experimental results show that the contouring motion controller designed in this paper has good system stability and anti-jamming ability which represent the good system robustness in the contour tracking experiment based on X-Y motor platform.