Magnetic Gradiometer for Car Detection and Speed Measurements

Goal of this diploma thesis was to design and manufacture magnetic gradiometer for car detection. Gradiometer would be designed with emphasis on lowest achievable noise level for possibility of large detection distance. Reduction of cost would be also on mind to be able to compete other commercial solutions as well as reducing power consumption and reduction of size. Another part of this thesis is focused to verify usability of magnetic sensors for correlation method of speed measurement. This method needs different sensor placement and different parameters of them are necessary. So complete different both hardware and firmware is developed for this purpose. Development of both sensor types has been fund by Technology Agency of the Czech Republic, grant No. TE02000202, Advanced sensors.

Keywords: Magnetometer, gradiometer, DRV425, HMC1021, AFF755, STM32, correlation, speed-measurement, FFT, RS485, AMR, fluxgate, MCU, microprocessor

Development version of the detector
During the development…
Another approach…
Semi-final prototype…
LabView in use…
Field of 3D magnetic sensors for mapping of the car’s magnetic signature…
Change in total field…
Camera vs. magnetic detector data comparison