Fachhochschule Lausitz, Senftenberg Systems Engineering MASTER THESIS SAMPATH KUMAR UPPU

1. Fachhochschule Lausitz, Senftenberg Systems Engineering MASTER THESIS SAMPATH KUMAR UPPU (Matriculation Nr.212835) Supervisors: FH Lausitz/ SE

2. Contents • Introduction • Problem definition • Importance of this thesis work • Measurement of Earth’s field by using fluxgate sensor • Theoretical explanation • Advantages of fluxgate sensor • Experimental Set-up and measurement procedure • Measurement results • Comparison of vehicle signatures and equipotential lines • Interpretations of the results • Discussions • Conclusion • Future prospects FH Lausitz/ SE

3. Problem Definition: • With the increase of traffic on the roads the current traffic detection systems(Inductive loops) which are placed just below the earth‘s surface are not reliable. • Finding the appropriate vehicle recognition system. Aim of the Project: • The fluxgate sensor implementation in traffic detection system. • Finding the the appropriate sensor location and its direction of placement. FH Lausitz/ SE

4. The earth’s magnetic field vector FH Lausitz/ SE

5. Ferrous object disturbance in uniform field: Vehicle disturbance in Earth‘s field: FH Lausitz/ SE

6. Comparison of different magnetic elements with their operational range: FH Lausitz/ SE

7. Comparison of low field magnetic sensors with the same resolution: FH Lausitz/ SE

8. Comparison of different magnetic sensors: FH Lausitz/ SE

9. Working Principle of Fluxgate Sensor: FH Lausitz/ SE

10. Layout Diagram of FGS1/COB07: FH Lausitz/ SE

11. Characteristics: • Two sensor axes are arranged in orthogonal directions. • The differential arrangement of fluxgate system filters out the even harmonics from the output signal. • With the differential arrangement the sensitivity will be twice as that of the single axis fluxgate sensor. • The output voltage is linear. • Low drift in sensitivity. • The excitation current required by ferromagnetic core to drive into saturationregion is 30-35mA. FH Lausitz/ SE

12. Advantages: • The sensor is not affected by weather conditions such as rain, fog, snow, wind etc., and dirt. • There is no problem to detect the vehicle even when the vehicle is projected into adjacent lane. • This sensor needs very low maintenance. • With this sensor both moving and standing vehicles can be detected. FH Lausitz/ SE

13. Experimental Set-up: FH Lausitz/ SE

14. FH Lausitz/ SE

15. Measurement Procedure: 300 250 200 150 100 50 0 50 100 150 200 250 300 350 40 60 80 100 120 FH Lausitz/ SE

16. Offset measurement: FH Lausitz/ SE

17. Measurement Results FH Lausitz/ SE

18. Measurement Results FH Lausitz/ SE

19. Measurement Results FH Lausitz/ SE

20. Comparison of magnitude field strength with respect to distance: FH Lausitz/ SE

21. Magnitude variation for different depths: Z-40cm depth Z-80cm depth FH Lausitz/ SE

22. Magnitude variation for different depths: Z-120cm depth • The sensors in the middle(16cm, -16cm) are showing more deviation and which are away from the center are showing less deviation of the field. • This effect is beneficial when a sensor has to detect vehicles in a single lane of traffic with other lanes present. FH Lausitz/ SE

23. Comparison of sensor signatures for different depths: FH Lausitz/ SE

24. Comparison of sensor signatures for different depths: FH Lausitz/ SE

25. Comparison of sensor signatures for different depths: FH Lausitz/ SE

26. Comparison of sensor signatures for different depths: FH Lausitz/ SE

27. Comparison of magnetic fields for a depth of 120cm: FH Lausitz/ SE

28. Comparison of magnetic fields for a depth of 120cm: FH Lausitz/ SE

29. Comparison of magnetic fields for a depth of 120cm: FH Lausitz/ SE

30. Comparison of magnetic fields for a depth of 120cm: FH Lausitz/ SE

31. Equipotential lines: Figure 21 Figure 22 Analysis of Equipotential lines: • Vehicle presence: Figure 24 FH Lausitz/ SE

32. Signal distortion due to the 50Hz power line cycle • Magnetic noise(Barkhausen noise). • Resistance noise(long cable): Calculated by Nyquist. • The measurements are taken by passing the car in steps of 20cm over the sensors. The position accuracy is ±1cm. • The Passat may not be driven exactly in the middle of the ramp. The variation is ±2.5cm. • Forward and Backward measurements. Accuracy limitations in measurements: FH Lausitz/ SE

33. Interpretations of the results: Overlapping of Passat on the signature: FH Lausitz/ SE

34. Vehicle Direction: FH Lausitz/ SE

35. Vehicle Detection: • Positioning the sensor: FH Lausitz/ SE

36. Figure28 Advantage of taking Bz for Vehicle Detection: B-Magnitude=√ (B2x+B2y+B2z) • To get the third-axis field the sensor is to be rotated by 90°. FH Lausitz/ SE

37. Sensors are to be placed symmetrically. • The waveforms at the outputs of the sensors are identical. • Vehicle’s velocity: • Vehicle length calculation: • Velocity and the magnitude variation • Vehicle classification: Discussions: • Velocitymeasurement: FH Lausitz/ SE

38. Some applications of vehicle presence in daily life: • Car Wash Entry/Exit • Drive-through System • Loading Dock • Gate closing • Traffic Detection • Intelligent parking Lots • Toll Ways FH Lausitz/ SE

39. Conclusion: • Achieved results: • Analysis of Bx, By, Bz, B-magnitude. • Drawing Equipotential lines. • Sensor which is very close: Earth’s field+ Remanence. • Appropriate depth for the proper signature of the vehicle is 100cm or 120cm. • Analysis of equipotential lines: • z-axis field is suitable for the vehicle detection. FH Lausitz/ SE

40. Correlation to Demands of Detection System • Noise correlation technique: • Extract the actual signal from the embedding • Differential arrangement of fluxgate system: • Twice the sensitivity • Power line cycle filter: • Noise is reduced • Signal to noise ratio is improved • With this method of measurement: • Vehicle signature is much accurate FH Lausitz/ SE

41. Future Prospects: • Finding length of the vehicle. • Classification of vehicles. • In this project the magnetic field in x, y, z directions are measured and from those B-magnitude is calculated. • Analyzing the Earth’s magnetic field vector () : Bx, By and Bz • Comparing the results with different vehicles. FH Lausitz/ SE

42. THANK YOU FOR YOUR ATTENTION FH Lausitz/ SE