System Design And Error Analysis Of Adaptive Grinding Machine Tool

As a key part of telescopes,lidar systems and other remote detection equipment,the machining accuracy of space mirror is undoubtedly one of the most important factors which affects the detection distance and precision a lot.As an important material of space mirror,the machining difficulty of silicon carbide has restricted the process of space mirror being large aperture and light weight.The attempt of new processing method is of great significance to reduce the processing difficulty and improve the machining precision of silicon carbide mirror.However,all of this is inseparable from the development of special equipment.According to the assumption of electrolytic abrasive belt grinding technology of silicon carbide,the control system of an electrolytic abrasive belt grinding equipment is developed.An open hardware system is selected for the grinding machine tool,which can benefit to the secondary improvement of machine tool in the later stage.At the same time,a special control application for the grinding equipment is developed with MFC tool,which can meet the needs of various functions.The developed machine tool needs to meet the requirements of high precision machining,and the existence of geometric error and control error is undoubtedly disadvantageous to precision machining.In terms of geometric error,the positioning accuracy of machine tool is improved by error compensation method.The mathematical model of geometric error of machine tool is established.In view of the traditional parameter identification scheme of nine lines method,some of its principle errors are analyzed.The geometric error is measured by the laser interferometer,and the geometric error parameter is identified by the improved nine-line method.The geometric error of the machine tool is compensated by the two-dimensional error compensation table of the PMAC control card,which effectively improves the geometric accuracy of the machine tool and verifies the effectiveness of the improved nine-line method.For the control error,by writing PLC programs and combining fuzzy PID control with PMAC servo algorithm,the dynamic adjustment of PID control parameters of grinding machine is realized.Through the single axis following error control and two axis arc interpolation error control experiments,it is found that the control accuracy of the machine tool has been improved to a certain extent,which has proved that fuzzy PID control is effective to improve the control precision.By the control of geometric error and position following error,the accuracy of the machine tool has been greatly improved.However,the actual performance of the machine tool has yet to be verified.Through the single factor experiments of belt grinding,the influence of the grain size,linear velocity and pressure on material removal and quality of machined surface are studied and analyzed.Good surface quality is obtained in the plane processing experiment,which proved that the developed grinding machine can meet the requirements of high precision machining.