Research And Design On Ultrasonic Data Acquisition And Processing System

Nondestructive testing is indispensable in the development of modern industry. To some extent, nondestructive testing, which has been generally acknowledged worldwide, reflects a country's level of industrial development.Ultrasonic detecting which can detect flaws inside an object is widely used in the field of nondestructive testing. However, conventional ultrasonic flaw detector has difficulty recording data, and can not analyze data quantitative.According to features of CTS-22 ultrasonic flaw detector, we design an ultrasonic data acquisition and processing system which base on the idea of virtual instrument.This system research and design has two parts:data acquisition system design and data processing system design.The system can digitize ultrasonic data, and send the data to a computer where data can be displayed, analyzed and stored.Ultrasonic data acquisition system based on STC89C52 MCU is responsible for A/D conversion of ultrasonic data, data buffer and data transmission.After buffered by the hi-speed RAM, ultrasonic data are sent to the data processing system though the USB port.Ultrasonic data processing system which is developed by LabVIEW8.5 is responsible for receiving data from data acquisition system, converting data to the waveform,analyzing the waveform and data storage.In the aspect of USB communication, we adapt a simple and rapid method to develop the USB system.In the LabVIEW environment, we develop the USB application program by NI-VISA subprogram controls, which shorten the developing period greatly.Several tests proved that the system's attainable frequency is 20MHz, which can meet the needs of data acquisition.Data processing system can display, analyze and store the ultrasonic signal well.