The System Of The Portable Bearing Fault Diagnosis Based On Ultrasonic

Rotating machinery is an important component of industrial production. Monitoringthe mechanical bearings real-time and predicting the fault trends have an importanteconomic significance. This paper designed a portable bearing fault diagnosis systembased on the Ultrasonic signals with portable, economical, practical and simple operationfeatures.The design includes two modules, the design of the hardware circuits and thesoftware programming parts. Hardware circuits are comprised by a signal conditioningcircuit device and an ultrasonic signal processing circuit device. Among the signalconditioning circuit device completes many functions, such as the ultrasonic signalpreamplifier; a bandpass filter, an adjustable amplification, envelope detection, and thevoltage level displaying. The ultrasonic signal conditioning circuit device employsSTM32F103VET6as its core processor on the basis of Cortex-M3. Its peripheralinterfaces include LCD interface, TF card memory interface, function key interface andserial communication interface. The reset circuit is designed in order to solve the abnormalworking of the device. The software programming parts exploit the IAR developmentenvironment and associated library module to develop many modules, such as data displaymodule, A/D converter module, function keys module, data storage module and serialcommunication module. And the function keys module is a key part of the program design,which coordinates the entire program running and gives a reasonable definition of thetimer interrupt and external interrupt priority. Its functions involve the changing of A/Dsampling frequency, the controlling of data storage and the switching of time domainwaveforms, histograms and frequency spectrum.The design establishes a histogram abnormal pattern mathematical model based onthe kernel density estimation method. The system gathers the abnormal operation data ofindustrial equipment on the basis of the existing conditions in the laboratory, andestablishes a database with the experimental data. Then, the system carries out the Matlabcalculation with the experimental data. It proves the validity of the validity of the mathematical model through comparing and analyzing both the experiment data and theactual industrial equipment abnormal conditions.