The Research Of Weight-in-Monitor (WIM) On Highway In High Speed

As an equipment of over-load inspect and vehicle's weight measure, the use of highway Weight-In-Monitor(WIM) system is not only propitious to know the types of the vehicle on the road, the chart of vehicle's shaft's loading, the degree of over loading and analyze the damage of overloading to the road for the traffic department but also propitious to make manage measures and principles as well as to be the efficient technical measurement for the road department who would charge according to the weight. So far, because of the vibration of the vehicles with high speed etc., the veracity, portability, low cost can hardly be improved in the system of WIM. To be satisfied the command of high precision,low cost and portable WIM system recently, at the basis of hydraulic weighting, it improves the weighting and anechoic calculating way by analyzing the closely related to prior knowledge. Firstly, after totally analyzing of the pressure which the vehicles get on the movement, the vehicle weighting calculating method was designed;By taking wavelet transform, the shaft weight signals was disposed by frequency. At the base of the closely related to prior knowledge, by the least square method simulating the main noise weight of the shaft weight signals so as to eliminate the noise, at last, by simulating to prove the efficiency of the method. Additional to that, the vehicles' speed were calculated by the method of autocorrelation analyzing, the method of displacement-integral to eliminate the period vibration was also tried. Beside to that, the particular design of the WIM system's hardware circuit and software structure were given. Because the signal of input channel was weak in the system, the signal of input channel circuit principle of hardware system and the layout of the PCB were expounded in details. In the course of design the embedded system software, the flow of process and the timing date sampling were introduced and analyzed as well.