The Design Of Tank Truck Loading Devices Positioning System

Nowadays, most petroleum enterprises in our country ship the petroleum by railway transport. Because of the capacity restriction of the fuel truck, plentiful coaches will be used for the transportation with complex loading process.Traditionally, operating personnel are required to fix the position manually of the loading equipment (usually is large crane tube) when filling every time. It is with great labor intensity and the personnel will feel fatigued easily, which may cause accident. Besides, the low speed of the manual butt joint is with little effectiveness. Therefore, it is necessary to apply an automatic filling position system to improve the filling effectiveness and decrease the working intensity. The popular resolution at present is to send the video capture information obtained by the camera to the computer to conduct. However, the computer is with large volume and poor stability because that it is not designed for industrial environment. It cannot adjust to the severe environment of the filling site. Thus, in this paper, a real-time conducting method is applied with the combination of real-time visual capture and high-performance digital processing unit, which improve the accuracy and stability of filling greatly.The innovation of the paper is to fix the position of the opening of the fuel truck by CCD camera. IEEE1394 universal serial bus is utilized as the transmission bus of the image. With the combination of programmable logic device (FPGA) and digital signal processor (DSP), build a high-performance disposing entirety to handle the image instead of the traditional method that the computer serves as the image processor. It is with low cost and consumption. Because of the application of purpose-made component, it is more stable compared with the traditional computer. This has great significance to the practical work and production.The paper first introduces the working principle of loading equipment of fuel truck and researches on the theory and development tendency of image position technology. According to the practical work environment, put forward the design plan of positional system of loading equipment of fuel truck. In terms of the design plan, provide specific design of the hardware and software. In the hardware aspect, use the CCD camera to finish the image capture, and then the data collected will be transmitted to FPGA through IEEE1394 butt joint to control the system. Finally the image collected will be conducted by DSP. In the software aspect, firstly provide corresponding software design according to the hardware design of the whole system. Then, in terms of the image character of the opening, provide specific achieving algorithm. For the algorithm, first is filtering the digital image of the opening with the neighborhood averaging method. This is to remove the image noise. Then finish the image binaryzation with big law method and confirm the edge of the opening. After that, confirm the centre of the circle according to the principle that on the circle, the cross point of the perpendicular bisectors of any two unparallel lines is the center of the circle. Finally, manage to fix the position of the loading equipment with PID algorithm according to the coordinate of the center of the circle.