Design And Development Of The Test Device Of The Ground Sensing Coil Based On Current Signal

In order to ensure the traffic safety on the road during driving motor vehicle safety,the traffic department takes the measure that the speed of the vehicle is limited by the intelligent speed measuring system.The intelligent speed measuring system include: video capture system,velometer,and other components of the server.The most widely used is the ground sensing coil.According to the verification regulation of automatic monitoring system for motor vehicle,the method of scence test or analog signal test is used to test the detector of the ground sensing coil.This paper designed a kind of current signal of ground sense coil velocimeter prover,the simulation method of current signal is as follows:The working principle of current signal simulation speed test method is to use our own interference of the coil.And interfere with the coil on the internal coil,verification equipment provides a current signal of the coil.According to electromagnetic field theory,the interference of coil produces a new magnetic field,the new magnetic field will change to coil magnetic field,the feeling of ground sense coil velocimeter detect ground sense coil magnetic field changes,which will make the changes as the vehicle passes through the ground sense coil signal and the corresponding processing measure vehicle speed.By comparing with these standard devices widely used in the market,the ground sense coil velocimeter verification can realize the ground sense coil speedometer calibration.In this paper,the design and development of the ground sensing coil measuring instrument of the innovation is as follows:(1)The electric current signal provided by the verification device is to be changed,and can simulate different types of vehicles.(2)The ground sensing coil speed measuring instrument can work in wireless mode,improving the verification efficiency and guarantee the safety of the staff.This paper is designed based on current signal ground sense coil speedometer calibration device,including hardware design and software design.Hardware design includes the current signal module,man-machine interactive display module,power supply voltage,current signal output module module,a microprocessor module and ZigBee controller module;Software design includes a source program written,burn,simulation,and cooperate with the hardware circuit implementation of prover joint debugging.After prover production has completed,we have selected the different manufacturer production of ground sense coil speedometer calibration to have tests,and gave the verification certificate.