Research On Key Methods And Techniques Of Real - Time Embedded Fuel Injection Detection Device

Real-time embedded system connects terminal embedded devices through the network, including data acquisition, industrial controller, PLC, sensor and so on that implement network control of production process, industrial equipment, intelligent detection and so on. Calculating element between the nodes on the premise of limited resources continuingly interact with physical objects. Parallelism of physical object, time of equipment action, time of network delay increase the stability of system and complexity of performance design with features to real-time, robust, autonomy, efficiency, and high performance. Acquisition device of fuel quantity is a typical real-time embedded system, mainly used in gas station network. Current acquisition method and device mainly use electric capacity type liquid level meter or ultrasonic liquid level meter to test the fuel quantity in the oil tank, used the different amount obtained before and after refueling to upload the Internet. These devices can meet the basic requirement for application of the real-time embedded fuel quantity acquisition device, but they only go for large vehicle’s tank of specification shape, going with low-security, great data error, and low-security of data. Therefore, to design vehicular real-time embedded acquisition device and method of fuel quantity for miniature vehicle’s normative tank, and to improve accuracy of acquisition data in premise of keeping safe of acquisition device and acquisition data are key problems for research and development of a real-time embedded device of fuel quantity acquisition.In this paper according to the above problems, on the detection method to use flow meters to directly measure the fuel quantity, the detection device is to design two kinds of information acquisition device for fuel tanks of different specifications improving the safety of detection, reducing measure error, having anti-theft tamper-proof function. On the basis, to design and to implement vehicle control processing terminal based on ARM11, to design the improved MD5 algorithm according to the project requirements, to research the security of data transmission, and to improve the anti-attacking of the testing data, the main research work in this paper focuses on the following aspects.1. Detection method. Based on the least square method used for estimating meter coefficient values, the algorithm was designed for a fuel tank with oil filler pipe, and the simulated experiment results showed that the algorithm has high accuracy of measurement and realized the adaptive dynamic instrument of coefficient value change. Based on reducing the measuring error of the jacketed ultrasonic flow meter with metal acoustic velocities instead of liquid acoustic velocity, the algorithm was designed for a fuel tank without oil filler pipe, and the simulated experiment results showed that the algorithm has significantly reduced the measuring error. Based on sound wave transmission path adaptive dynamic correction, the algorithm was designed for pipe sections of ultrasonic flow meter, and was proved that it improved the accuracy of measurement by theory.2. In the design of detection device, the design analyzed the working principle and the advantages and disadvantages of existing fluid testing instrument, selected turbine flow meter and ultrasonic flow meter as core instruments of information detection of fuel quantity. It designed an outside device structure of turbine fuel quantity information acquisition for a fuel tank with oil filler pipe, designed the equipment hardware based on the actual demands, and gave a brief description about the required hardware. It developed software on the basis of the hardware design, and gave the detailed process of the fuel quantity measurement. It designed a fuel quantity information acquisition device for a fuel tank without oil filler pipe, realized full package based on the mechanism of drain-pipe gravity flow and pressure flow, and the design of device structure had considered the safety and security design.3. In the method of vehicular real-time embedded control data processing, the method designed the improved MD5 algorithm that protects data from being tampered, verified the MD5 algorithm of collision, and solved the data transmission security problems.4. In the design of vehicular real-time embedded control processing terminal, the design delivered vehicular processing terminal based on ARM11 development board and Android platform, realizing the acquisition, processing, transformation, and encryption of GPS data and fuel quantity data.