Dsp-based Cnc Machine Tool Breakage Condition Monitoring System

With the development of automatization and intelligentize manufacturing technology, exigent demand has been put forward for the equipment's cutters, for the example of NC machine and machining center, to monitor their working state real-timely. As a result of an automatization and intelligentize environment, cutters'abrasion and breakage have large impact to the quality of workpieces, even breaking the machine. So, it is quite necessary to establish a system of cutters'work-state monitoring with high dependability and strong real-time.In the numerical control processing process, the effective monitoring cutting tool's damage has the very important function safely to the quality assurance and the numerically-controlled machine tool. The cutting tool active status's monitoring is a device management function important constituent, although the cutting tool is produces the chamber of commerce in leaving the plant to provide cutting tool's some parameters, like biggest process period, biggest processing number of times and so on, but these only belong to the cutting tool life management category, has the sudden outbreak to the processing process in not to be able to carry on the judgment and to control effectively.Cutting tool in components processing process, if has the unusual damage is the breakage, if cannot discover promptly, will cause to process the components the damage and the abandonment, will create the certain extent to the engine bed the destruction; If cutting tool's information very good management, has not caused cutting tool's use to be very chaotic, like this will reduce cutting tool's service life, will cut the processing efficiency, will increase the production cost. Therefore, establishes a set of effective cutting tool active status the monitoring method and consummation management especially important.The study to for the cutters'monitor involves hereinafter several problems: First, which kind of signal should be gathered and what is the relationship between signal and cutter's state; Second, how to gather the chosen signal and how to exclude the disturbance signal in order to pick-up efficient signal; Thirdly, how to rightly identity the signal and whether to react timely when finding the problem.When tool wear sends out sound transmitting message scope and frequency size and tool wear degree related, but the sensor gathers in the primary signal was promiscuous has processed the scene each kind of unwanted signal, must enhance the signal the validity, must remove these unwanted signal. In view of this, may process through the wavelet technology. The wavelet ratio of transformation Fourier transformation superior place lies in decides the signal unstable processing. Transforms compared with Yu Fu, the wavelet transformation has the localization characteristic, it may focus to the target signal random detail, very suitably to tool wear and breakage signal analysis. To the point of upwards problems, AE signal which is systemically studied has been chosen as the monitor signal of cutter's state by comparing and analyzing several significant signals; it largely reduces the disturbance signal's impact and improves the dependability by use of the technology of wavelet-lower-voice to the signal processing.This article using of TI Company's TMS320F2812 series DSP which has strong ability of gathering data and high capability of real-time as the core establishing the hardware system of downward PC data gathering, programming by applying the powerful integrated development environment CCS (Code Composer Studio) . This article has developed the peripheral circuit specially for it, has compiled the data acquisition master routine, A \ the D conversion routine, the digital filtering procedure as well as the reaction control procedure; Uses the serial port technology and USB transfers the serial port technology two way same superior machine communication, causes the data the transmission mode to be diverser.This article developes the system interface with NI Company offered virtual instrument develop software LAB View. Has realized graphical display based on the hypothesized instrument's superior machine data transmission and that using the software bringing FFT module, the wavelet analysis module processes the signal which gathers, simplified the data processing analysis complexity, reduced the programming difficulty, raised the efficiency. Using LAB View software development system's main contact surface, but also has the status recognition, the warning instruction, the parameter optional as well as functions and so on cutting tool information database. Consequently establishes the real-time monitor system for the NC machine's cutters'state based on DSP and Lab VIEW.According to the debugging, simulation, and testing in the machine working scene, the result indicates that this system can exactly and reliably judge the cutters'state of abrasion and breakage.