The System Of Axle End’s Image Acquisiton And Processing Based On Nios Ⅱ

The axle, which connects the wheels of the train, plays an important role on the safety operation of the train. Once the power axle went wrong, train would derail and even the whole train directly would fly out of orbit with a serious accident. Therefore, in order to guarantee the safety of train operation and people’s property and life, the train axle must be inspected regularly. At present, detecting and recording of axle is entirely artificial record, which is time-consuming, but also trouble.With the appearance of a large number of low-power, low-cost and high performance embedded processor of RISC, the image processing changes from the traditional PC to system on chip. With the feature of axle end’s number and the trend of the image processing, the embedded system based on NIOS II has been designed, acquisition and processing of the axle end image.First of all, the article has presented the overall research scheme of the embedded system on chip on NIOS II, and built the foundation of SOPC system. The basic components contain of NIOS II CPU, EPCS, RAM, PIO, DMA, JTAG UART and SRAM IP.Secondly, this article has designed the Image Control module and the DCFIFO module. The Image Control module contains of a dcclk_transition module, Camera Control module and Sobel Processor module, completing the conversion of the different clock domains, control of the image sensor, acquisition, gray and Sobel edge extraction of the end image; The DCFIFO module completed the control of asynchronous FIFO, caching the image data cross different clock domains.Finally, the article has completed the main NIOS II program, bringing about image data’s ping-pong operation with two DMAs, which improved the data transmission rate and the efficiency of the CPU. Programming the MFC and dong the experiments, the system reached the expected requirements.