Study On Monitoring And Control Of Machining Process Of NC Machine Tool

Concerning"Made in China 2025",on-line monitoring,data acquisition,fault alarming,etc.in industrial production process need further study so as to develop high-flexible,high-individual and networking production chain that can manufacture intelligently.As one of the key components of intelligent production,the CNC machine tool may experience dual influence both from external and internal factors in its manufacturing process,thus leads to its nonlinearity,uncertainty and hysteresis.In order to improve the stability,robustness,machining quality and efficiency of CNC machine,its machining process was monitored and its control system was adjusted using on-line parameters as well.These measures can also weaken vibration,noise,thermal deformation and other undesirable phenomena in manufacturing process,and increase lifecycle of equipment.Feeding system is one of the key components of CNC machine,accordingly,plays significant role in monitoring and controlling its machining process.This thesis mainly studied an experimental platform of CNC feeding system.Relevant national standards were combined with the practical production needs;monitoring system and control technology of feeding system based on NI CompactRIO system were also developed.The research can be divided into the following sub-sections:(1)Focusing on Kollmorgen motor in the drive system,which is the 'brain' of the feed system.Mathematical model of the motor were established so as to perform further analysis and research on the structures and working principles of the motor.The mathematical model of the motor was built and simulated using Lab VIEW.Modelling and simulation using Lab VIEW may have some advantages such as easy to use and high efficiency.According to the practical working conditions and control requirements,selecting appropriate control programs for the control process so as to provide an intelligent controller and solutions.(2)Studies on the monitoring system of CNC feeding system based on NI CompactRIO embedded system,mainly include motion control,data acquisition in machining process,and choice of the object used to measure vibration and temperature.Development using Lab VIEW mainly used NI CompactRIO system,motion control,signal acquisition,data analysis,storage and other modules,and validations of the effectiveness and stability of the monitoring system were finished using the final test.Motion control was designed by setting different parameters and input signal modes;the machine tool was also monitored and it can report early warning to provide useful data and solutions through the expansion of data acquisition card,multi-channel multi-type data acquisition,CNC machine tools for a full state.(3)Fuzzy PID controller was designed,and motor speed data was collected as input source of the controller so as to realize the real-time feedback of the speed signal in the processing site.In addition,an adaptive fuzzy PID controller was used to achieve the operating status of self-tuning PID parameters on the scene of CNC machine tools.Meanwhile,real-time and on-line adjustment of motor operating parameters was realized,and intelligent adaptive control effect was achieved to meet the stable and precise operation of the feed system.In this thesis,monitoring and control of the CNC machine in its manufacturing process were studied,and a relatively perfect monitoring system was developed.Our research provides practical value and guidance for achieving the intelligent development of CNC machine tools,intelligent production and intelligent devices.