Design Of Real-time Digital Ultrasonic Flaw Detection System Based On DSP And FPGA

Ultrasonic flaw detection is one of the most widely used non-destructive detection methods in industry.It can accurately detect the internal defects of metal and non-metallic substances.The ultrasonic flaw detection system has adjustable parameter excitation,efficient echo signal pre-processing capability and real-time performance,which is of great significance to the efficient application of ultrasonic flaw detection technology.At present,there is no ultrasonic flaw detection equipment with the capability of real-time echo signal preprocessing and the function of transmitting pulse parameters adjustable.In order to make up for this deficiency,this paper designs a real-time digital ultrasonic flaw detection system based on DSP and FPGA.Firstly,the hardware circuit of ultrasonic flaw detection system is designed to solve the defects of single excitation pulse adjustable parameter and poor real-time performance in traditional ultrasonic flaw detection system.According to functional requirements of ultrasonic flaw detection system on the hardware circuit module partition,and the detailed design which has the function of pulse adjustable ultrasonic transmitting circuit,with programmable gain and multiple sampling rate regulating function of echo receiving module circuit,which has the function of high speed data transmission and echo signal processing real-time communication processing module circuit,determines the ultrasonic flaw detecting system hardware circuit and software interface.Secondly,the software program of ultrasonic flaw detection system is designed to solve the problems of hardware circuit parameter adjustment,communication and echo signal preprocessing.According to the requirements of the system hardware circuit to realize the function of the detailed design the excitation pulse parameters regulating function of ultrasonic transmitting module control logic,gain and control function of the sampling frequency echo receiving module acquisition control logic,high-speed communication and digital filter function of DSP software program,with functions of high speed data transmission of FPGA and DSP communication logic and USB2.0 communication program,and then developed to waveform shows that interact with the system control function of upper machine software.Finally,the design and production system printed circuit board,complete the development of ultrasonic flaw detection system.The performance of the regulation function of the system excitation pulse is tested by the oscilloscope,and the performance of the regulation function of gain and sampling frequency is tested by the upper computer interaction software.The experimental platform was built to conduct ultrasonic flaw detection experiments on simulated defective specimens.The upper interactive software was used to collect and display ultrasonic echo signals containing defect information,and the experimental process and analysis were completed.