Research On Geomagnetic Induction Vehicle Detection Method

Now days,the traffic conditions are become more and more complicated.In order to achieve the traffic signal is controlled in real time and the traffic information interacted,we must detect the vehicle.Vehicle detection technology is the basis of traffic signal control system and traffic information system.It is an important factor to determine whether the system operate in real time and efficient.As a new detection technology,geomagnetic induction vehicle detection has attracted more and more attention with its unique advantages.Compared with other detectors,geomagnetic vehicle detector has several advantages can be listed as follows: less space,installation easy,restricted small-relatively by the environment,reliable.So it is of great value and development potentials.This article has developed a device for detecting the change of earth’s magnetic field.The device translate from the geomagnetic perturbation which caused by the pass car into alternating voltage signal.Then,the Traffic Detection and vehicle type recognition would be studied by this vehicle geomagnetic data.the vehicle through the top of the device is caused by the geomagnetic disturbances are transformed into the change of voltage signal and based on these vehicles geomagnetic information were on the method of traffic flow detection and vehicle recognition.The main research results are as follows:(1)According to the basic principle of geomagnetic vehicle detection,we design a geomagnetic vehicle detection system based on the integrated module of HMC5983.This system can collect the Earth’s magnetic field accurately and gain some breakthrough in data sampling rate.It realizes maximum 220 Hz sampling rate.(2)Analysis the elements of geomagnetic signal,we put forward the prevent pulse jamming average filtering algorithm to filter the geomagnetic signal and the state machine detection algorithm is used in Traffic Detection by the waveform characteristics of signal.In the road environment test,this system’s accuracy which detects vehicles can reach98.6%.It can meet the requirement of collect traffic volume data in Traffic Signal ControlSystem or Traffic Information System.(3)We study the feasibility of vehicle classification by geomagnetic perturbations that caused by the collect data which come from the various types of vehicle.On the basis of many kinds of methods’ advantages and disadvantages,we use the method of Support Vector Machine Decision Binary Tree(BTSVM)to research the vehicle classification and improve the BTSVM.Finally,we check the method has a good effect in the speed and accuracy by the experiment data,and attain expectant efficacy.