Vibration Test System Development For Machine Tool Based On USB 2.0 Interface

In recent years, according to enginery specialty undergraduate (college) experiment curriculum "Mechanism Manufacture Technology Basis","Mechanical Vibration"," Mechanical Test Technology" and so on, measurement experiment system of machine tool vibration based on USB 2.0 high speed interface was developed. The USB 2.0 interface used in the data acquisition module of the system can be accepted easily by the most of users because of its simple use, quick speed, strong compatibility.This article separately introduced this experiment system from two parts: the software and the hardware. The software part is complied by Visual Basic, for the purpose of measuring the absolute vibration signal of headstock ,as well as finishing the vibration signal spectral analysis, measuring the relative vibration signal between the lathe simulation workpiece and tool holder, reading out precise rotational speed of lathe spindle; The hardware part mainly includes the conditioning circuit board, the module using USB2.0 interface to collect and transmit data, computer and so on. first introduced the USB architecture and the related content about data stream, then emphatically describe why to select USB2.0 chip CY7C68013A which is produced by CYPRESS Corporation and how to realize the data transmission and the gathering. By means of designing CY7C68013A GPIF and the AD hardware interface circuit, compiling the firmware of CY7C68013A chip under the Keil C51 platform, using VC++6.0 to complete the Windows2000/XP driver of USB module and the general dynamic function library, the experiment system was realized based on USB2.0 connection under data high speed gathering and the transmission, and is better than other transmission modes in transmission speed, installment as well as compatible questions.There are six technical chaeracteristics in the system:①Practical, it was just developed for the experiment. In the experiment, the phenomenon of vibration of the machine tool can be initially understanded, how to measure vibration by the instruments and methods can be appreciated, and the initial understanding about the spectrum analysis of vibration signals and the concept of dynamic balance are given;②The self-designed USB data acquisition module with high integration, low power consumption, low cost, USB plug-and-play ability, the strong compatibility, uses USB bus-powered without external power supply and so on are characteristics of hardware part.③USB2.0 data acquisition module using a common programmable interface (GPIF) mode to control external circuitry timing of the data collection, transmission functions, can obtain more precise control of timing, and use graphical interface programming for interface GPIF debugging, so that development cycle is greatly reduced;④The synchronization signal as one bit of data and 12 bit of data from the AD conversion are received by the GPIF interface through the 16 bit data bus to ensure that the synchronization signal and analog signals are simultaneously collected;⑤USB2.0 interface module using DMA transfer mode, solving the problem that enhanced 8,051 of USB chipset restrict the transmission speed, can fully meet data collection between the 300K and 5M frequency under the fast and stable condition;⑥Desiging the general dynamic function library for communications between USB2.0 data acquisition modules and PC, ensure customers easily to write the programs under different platforms. This USB data acquisition module has reached the commercialization and mass production conditions.Through In-depth making a study of the vibration measurement of machine tool, USB bus principles and signal acquisition and processing, the vibration measurement system of machine tool has been successfully developed, and after testing USB device compatibility, transmission speed, digital I/O behavior and other performance of data acquisition modules using USB2.0 interface, its basic indicators have all achieved the expected targets.At the end of the article there is a summary on this subject and a number of ways to improve the current design of experimental system, especially the data acquisition module are given. At last how to expand the functions of this system is...