Research Of Ultrasonic Testing System Based On ARM Controller

Ultrasonic testing is a very important method in Non-destructive Testing. It has been widely used to control the quality of on-line product and inspect equipments and some important components. The research of the digital ultrasonic testing device has become an inevitable trend in the world. In this thesis, based on microcontroller of ARM, the key techniques of the ultrasonic testing system are studied and developed for the detection of steel.The main work and achievements of the research are as follows:Design and implement the front breadboard of the ultrasonic detector system, which mainly includes the protection circuit, the high-frequency amplification circuit, the filter circuit and the detecting circuit. The circuit of the front breadboard is designed and the hardware is tested through experimental verification. Furthermore, the acquisition board is capable of providing the testing range of 500Hz～10MHz, the minimum signal of 0.01mv, and the control accuracy of 0.1db.Design and implement the high-speed acquisition circuit board and research the parameter of ultrasonic testing system. With the real-time and high-speed processing capability of ARM controller and the FPGA, the high-speed signal acquisition circuit board is designed. Reseach the full-wave signals acquisition, of which the highest acquisition rate can be 40 MHz.Design and implement the software of supersonic testing system, including the control of the emission, receiving, amplification, noise processing, data collection, display of echo graphics, test results storage and playback and output in the process of analog signal transmission. Through the software, the full wave signal at the sampling frequency of 40MHz can be displayed in the LCD.Implement full-wave algorithms of digital signal processing. Apply the Butterworth digit filter in the detection of full-wave, which can improve SNR of signal less than 10MHz.