Research On Data Acquisition And Online Chatter Monitoring Platform Based On Open Numerical Control System

With the widespread application of computer technology and sensor technology in the manufacturing field,the amount of data in modern production has increased exponentially,providing necessary conditions for a data-driven manufacturing model,and at the same time putting forward new requirements and challenges to traditional manufacturing platforms.In recent years,thanks to the improvement of general-purpose computing hardware capabilities and the widespread application of distributed systems in various fields,the development of general-purpose computers as computing platforms,open CNC systems as control systems,and distributed architecture cluster deployment data Storage system becomes possible.This article is based on the open CNC system Linux CNC,using Ether CAT fieldbus as the communication method,and a data acquisition module integrated in Linux CNC is developed.Kafka message queue is deployed through a distributed architecture,which realizes the decoupling of upstream and downstream data.Also,a Mongo DB database cluster was built to store diversified data strucuture,ensuring high availability and high reliability.In order to realize online monitoring of machining status,this paper proposes an online chatter monitoring algorithm based on nonlinear energy operator.The periodic forced vibration signal is extracted through Kalman filter,and the amplitude and frequency of the chatter signal is estimated by nonlinear operator.Chatter condition is captured based on the ratio between the chatter energy and the total signal energy.This method is suitable for discrete time domain,and can judge the chatter state with high time domain resolution,and has a smaller update period than the traditional fast Fourier transform.In this paper,the algorithm is deployed in Linux CNC as a Hardware Abstraction Layer module,and the real-time performance and effectiveness of the data acquisition platform and the online chatter monitoring module are verified through the experiment of milling thin-walled parts.