Research Of Ultrasonic Testing System Based On Arm Control

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 inevitable trend in the world. In the thesis, based on microcontroller of ARM, the key techniques are studied and developed for the detection of steel in the ultrasonic testing system.The main work and achievements of the research are as follows:Based on the investigation on technical parameters of ultrasonic testing system, the front breadboard of the ultrasonic detector system is designed and implemented, mainly including the protection circuit, the high-frequency amplification circuit, the filter circuit and the detection-circuit. The circuit 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 0.01 mv, and the control accuracy of 0.1 db.Based on researching the parameter of ultrasonic testing system, the high-speed acquisition circuit board is designed and implemented. With the real-time and high-speed processing capability of ARM controller and the FPGA, the high-speed signal acquisition circuit board is designed. The full-wave signals can be obtained on the basis of full-wave signals, and the highest collection rate can reach 40 MHz. Besides, the high-voltage drive circuit, including the Emission-circuit, is devised to supply drive capability for portable detectors.The software of supersonic testing system is designed and implemented, including 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 detection signal in the sampling frequency of 10 and 20MHz and the full wave signal in the sampling frequency of 40MHz are showed.Researching on full-wave algorithms of digital signal processing and using digital signal processing technology, digital filtering algorithm is studied for the storage-echo-signal.The Butterworth digit filter is proposed and applied in the detection of full-wave. The experimental results certify that it is available and rational.