Vehicle detection sensor

Abstract

The invention discloses a vehicle detection sensor which comprises a magnetic field detection device for detecting with a fixed frequency, establishing and recording a magnetic field value in a staticstate to record as an initial magnetic field value, and capturing the time when magnetic field starts to change and recording the time as the initial change time; an ultrasonic positioning device forcarrying out positioning judgment according to the fixed frequency, determining and providing the information whether there is a vehicle on the current parking space to correct the parking space output state information; and a doppler radar detection device for activating a doppler radar detection device when the magnetic field change is detected. The magnetic field detection device and the doppler radar detection device jointly complete data recording, and the parking space occupation information is finally given by combining the positioning judgment of the ultrasonic positioning device. According to the vehicle detection sensor, the doppler radar detection device and the ultrasonic positioning device overcome the defects of a magnetic field detection device in dynamic detection and static monitoring respectively.

Description

technical field [0001] The invention belongs to the field of parking space detection, and more specifically relates to a vehicle detection sensor. Background technique [0002] For vehicle detection sensors that rely on geomagnetic detection technology, it is by detecting the variation of the earth's magnetic field on the parking space to determine whether the parking space is occupied. When a vehicle is parked in a parking space, it will interfere with the earth's magnetic field, which will cause a change in the amount of the earth's magnetic field on the parking space; the geomagnetic sensor judges that there is a vehicle occupying the parking space by sensing, detecting and quantifying this change; this type of sensor exists Two use problems make it impossible to accurately judge the occupancy of parking spaces in actual use, which affects the actual use effect. [0003] One is the magnetic field interference problem of adjacent parking spaces. Due to the different magn...

AI Technical Summary

Problems solved by technology

This directly affects the accuracy of the parking lot information

According to the case experience, the parking space detector based on pure geomagnetic detection technology has an accuracy rate of about 90% of the parking space information; this obviously cannot meet customer needs;

[0004] Second, the initial state cannot be automatically judged

The magnetic field detector can only judge the dynamic information of the vehicle through the disturbance law of the vehicle magnetic field. Its initial static magnetic state must be manually set periodically to ensure its normal operation, resulting in a large manual maintenance cost

Once the initial state is wrong, the sensor will always output the information of the parking space with a car, or the anti-logic information, which will also affect the accuracy of the parking space information

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