FPGA-based 3D Ultrasonic Imaging Detection System

With the gradual maturity of ultrasonic testing theory and the extensive accumulation of practice and the rapid development of electronic technology and computer technology,ultrasonic testing system is developing towards the direction of digitization,automation and intelligence.Considering the current high price and low openness of related products at home and abroad,which bring many limitations and inconvenience to the researchers.Therefore,this project independently disigns a perfectly functional ultrasonic detection system based on depth investigation of the domestic and foreign market.In this paper,the following functional modules are designed according to the modular design method: high-efficiency flyback switching power supply,which can realize open-loop and closed-loop continuous output high-voltage adjustable;highperformance multi-channel pulse transmission module,pulse width,pulse frequency,pulse number and the repetition frequency of the pulse emission can be adjusted to adapt to different piezoelectric sensors and different detection tasks.The working mode supports reflective and transmissive types,which can be flexibly adapted to different detection scenarios.With high voltage protection module,which can realize high voltage and low voltage's isolation.The ultrasonic receiving circuit has a total of 8 channels and can work independently at the same time;The gain range includes optional LNA gain settings,attenuator gain settings,PGA gain settings,and ADC digital gain settings,which can achieve signal amplification up to 60 d B;support highpass filtering and low-pass filtering;sampling frequency up to 65MHz;support data Real-time upload via USB;simultaneous control of multiple motion mechanisms,realtime control of the running direction and speed of 3 motion mechanisms at the same time.In terms of hardware circuit design of the instrument,the transmitter circuit,receiver circuit,motion control circuit,and central control circuit were designed.The logic design of the FPGA uses the Verilog HDL hardware description language,and is divided into a global reset module,A / D module,cache module,and SPI protocol module according to the modular idea.The software uses Lab VIEW programming to realize human-computer interaction,and it can send ultrasonic detection parameters and motion mechanism control parameters in real time.The performance test results of the instrument show that the modules of the ultrasonic circuit have basically achieved the technical indicators and can be applied to non-destructive testing,providing a technical basis for ultrasonic phased array testing,further expanding the digital processing functions of echo signals,and realizing the imaging of ultrasonic testing,Automation and intelligence have laid a good foundation,with a wide range of application prospects and development space.