The Research And Design Of Full-vehicle Dynamic Weighing Instrument Based On The BP Algorithm

At present, there are many problems which exist in the use of axle load type dynamic weighing system. Such as the low efficiency in traffic, the low weighing precision, the system can’t weight effectively ultra long, ultra width, and special vehicles, the toll station often appear congestion, quarrels phenomenon. Therefore, the vehicle type dynamic weighing system are gradually recognized by user because its high precision and high efficiency. The vehicle dynamic weighing system combined its technology with the vehicle type static weighing platform, the system not only improve the weighing accuracy,but also can effectively prevent vehicles irregularities evading tax.Weighing instrument is the core module of the weighing system, its function and performance directly affect the weighing precision and the work efficiency of weighing system. According to the technical requirements of vehicle dynamic weighing system, the paper put forward the scheme of dynamic weighing instrument, the scheme divided into three parts hardware design, software design and weighing algorithm design. The main contents of this paper are as follows:First, the paper introduces the research background and significance of the dynamic weighing system and instrument. According to the research status and the development of related fields at home and abroad, the design scheme of system and instrument was put forward. At the same time, the structure of the arrangement is introduced in this paper.Second, it introduces the composition of vehicle dynamic weighing system structure, and describes the system components working principle and the system working mode in detail.Third, according to the requirements of the technical scheme of vehicle dynamic weighing system, instrument hardware circuit was modular designed. According to the principle of the sensor parallel circuit, sensor pre-processing circuit was designed.Fourth, vehicle dynamic weighing instrument software was designed based on multithreading modular programming technology in the WinCE which embedded operating system. Instrument screen program was designed in the view of the MCGS configuration software. The process of modules program design and main code were described in detailFifth, according to the characteristics of the vehicle type dynamic weighing signal, the weighing signal processing which combinig the improve algorithm of Sub-band reconstruction with BP neural network algorithm. Matlab simulation model is established.Sixth, the vehicle type dynamic vehicle weighing data was simulated, and instrumentation was used in the actual project. Through on-site application, the weighing accuracy and feasibility of the instrument were verified.Seventh, it summarizes the design work, and is looking forward to the future weighing system and instrument development.The innovation of this design are as follows:First, weighing load device adopts multiple mesa, long scale body structure design. The system is a dynamic vehicle weighing and has the characteristics of continuous uninterrupted weighing more than one car. It aslo have the advantages of high traffic efficiency and high precision weighing.Second, the instrument hardware use EPC- 8000 industrial control board as the core of modular circuit design, The software is designed based on multithreading modular programming technology in the WinCE which embedded operating system. The instrument have the characteristics of speed processing, high efficiency and good redundancy.Third, the weighing signal is filter preprocessed using the improved algorithm SUB-band reconstruction, and then process again using BP algorithm which combines models, speed and acceleration of the weighing signals.It is not only ensure a stable and reliable operation of the system, but also improve the weighing accuracy.The subject of the designed instrument has been run more than two months of highway toll station, the weighing system is stable and reliable, and overall system performance has improved so much than the axle weighing system. Application of the design algorithm weighed signal processing, vehicle weighing error control in less than 1% meeting the national standard“JJG 907-2006 dynamic vehicle test procedures”set forth in claim 1 level scale error.