Design Of Ultrasonic Phased Array Real-time Total Focusing System Based On FPGA

With the development of society and the needs of industrial production,ultrasonic non-destructive testing equipment is widely used in industrial pipelines,railways,aerospace and other fields.An total focusing method(TFM)based on ultrasonic phased array detection has higher focusing accuracy and stronger defect characterization ability than traditional phased array,and is called "Golden Rule".However,this method needs full matrix capture(FMC)first and then processes the data,which requires a large amount of data and calculation.It's difficult to achieve real-time imaging and meet the needs of industrial field applications with this method.Therefore,there is a need to carry out research on real-time TFM.Based on the parallel characteristics of the hardware platform and the total focusing indexing algorithm,this paper focuses on the related research on realizing real-time total focusing imaging with the hardware acceleration platform,and designs an ultrasound phased array real-time total focusing system based on the X86+FPGA architecture.Based on the principle and parallel characteristics of the TFM,the thesis uses the data index method to achieve total focusing imaging.This paper analyzes the design requirements of the system,combined with the parallelism of FPGA operation,puts forward the hardware architecture of X86+FPGA as the overall design of the ultrasonic phased array real-time total focusing system.The paper discusses in detail the design of the digital circuit schematic diagram in the hardware circuit of the phased array real-time total focusing system with the X86 module as the core board and the backplane FPGA chip as the calculation core,including the backplane DDR3 memory circuit design,QSPI flash circuit design,AD9681 data acquisition circuit design,USB interface Circuit design,LCD display circuit design,and power system circuit design.We built a phased array real-time total focusing system experimental circuit board.The main calculation of the system is implemented in FPGA.The overall performance and operation efficiency of the system are only related to FPGA.The paper gives a detailed design description of the main state machine program in FPGA,including the working principle and configuration method of high-speed acquisition chip AD9681,the design principle of high-speed data transmission XDMA module and AXI bus,the design principle of high-speed data processing index superposition algorithm and quadrature phase detection algorithm.And then we captured the internal signal of the chip through the logic analysis function of the software Vivado,tested and analyzed the waveform data,and verified the correctness of the program function.In order to verify the working performance of the designed phased array real-time total focusing system,this paper integrates the designed system with an ultrasonic probe,inspects the scratch test block,and compares the test results with the conventional ultrasonic phased array inspection results.The results show that the designed phased array real-time total focusing system has better detection capabilities and defect characterization capabilities than conventional ultrasonic phased arrays.And the imaging time of the algorithm accelerated by hardware is about 8.52ms,which can meet the needs of industrial real-time imaging,and the functions and performance have reached the expected goals.