The Design Of Data Acquisition System For CNC Gear Measuring Center

Recent years,high tech gear measuring instrument was developed in the CNC(Computer Numerical Control)Gear Measuring Center,compared with the traditional mechanical gear measuring instrument,it can not only measure the gear,but also measure the gear cutter(hob,gear shaving cutter,gear shaper cutter etc.),worm gear,cam shaft and other complex work piece,automatic detection,high precision,fast,comprehensive.A fixture could automatically complete a number of parameters measurement of the work piece,it required a high-speed Data Acquisition System to ensure data in high speed measurement and acquisition and transmission.In this paper,CNC Gear Measuring Center in high speed measurement under the condition high speed of multiple data,high precision,synchronous data acquisition,processing,upload,analysis of demand,it need designed a Data Acquisition System.The thesis firstly introduces the study status of CNC Gear Measuring Center at home and abroad and the Data Acquisition System,metering sensor principle of work through the application to CNC Gear Measuring Center is analyzed,achieving the technical indicators,improving the design of the new to the traditional Data Acquisition System exists,determine the design of Data Acquisition System used kernel mode for the CPLD+STM32.The Data Acquisition System needed to capture signals for the tangential(X),Jing Xiang(Y),axial(Z),and circular turntable(C)probe signal of four road of grating signal and Jing Xiang on the Y axis.Four road grating signals subdivision by CPLD,16 bits resolution to counting processing.CPLD would counter by the number of latches,four choose a data selector to STM32 was stored in external FIFO memory.Probe signal through the linear variable differential transformer(LVDT)special signal conditioning chip AD698 signal conditioning,filter through two Sallen-Key active low,controlled by the STM32 16 bits AD976 A is converted to digital collection storage.The data acquisition is completed by the STM32 control W5100 Ethernet communication mode is transferred to the PC machine.The software design includes STM32 control AD976 A conversion program,driver program design of W5100 Ethernet communication,LabVIEW development environment program of the computer user monitoring data interface.Proved by experiments,the Data Acquisition System design was completed can improve the precision of data acquisition of CNC Gear Measuring Center,work stable and reliable.