Multi-sensor anticipatory object detection system

• US 5,872,536 A
• Filed: 02/19/1997
• Issued: 02/16/1999
• Est. Priority Date: 02/19/1997
• Status: Expired due to Term

• Current Assignee: Hittite Microwave, LLC (Analog Devices, Inc.)
• Original Assignee: Hittite Microwave Corporation (Analog Devices, Inc.)
• Inventors: Lyons, Christopher T., Taskin, Ismail
• Primary Examiner(s): Sotomayor, John B.
• Application Number:
  US08/808,939
• Time in Patent Office: 727 Days
• Field of Search: 342/70, 342/71, 342/72, 342/106, 342/107, 342/193
• US Class Current: 342/70
• CPC Class Codes: B60R 21/013 including means for detecting collisions, impending collisions or roll-over
• CPC Class Codes: B60R 21/01332 by frequency or waveform analysis
• CPC Class Codes: B60R 21/0134 responsive to imminent contact with an obstacle , e.g. using radar systems
• CPC Class Codes: G01S 13/42 Simultaneous measurement of distance and other co-ordinates indirect measurement G01S13/46
• CPC Class Codes: G01S 13/582 adapted for simultaneous range and velocity measurements
• CPC Class Codes: G01S 13/584 adapted for simultaneous range and velocity measurements
• CPC Class Codes: G01S 13/72 for two-dimensional tracking, e.g. combination of angle and range tracking, track-while-scan radar
• CPC Class Codes: G01S 13/87 Combinations of radar systems, e.g. primary radar and secondary radar
• CPC Class Codes: G01S 13/931 of land vehicles
• CPC Class Codes: G01S 2013/93271 in the front of the vehicles
• CPC Class Codes: G01S 2013/93275 in the bumper area

Abstract

A multi-sensor anticipatory object detection system for detecting the instantaneous range, relative velocity, collision angle and point of impact of a colliding object includes a plurality of transducer devices angle a fixed distance in which each said transducer device transmits a modulated carrier signal and receives the reflected modulated carrier signal from an object; a detection device for detecting a plurality of Doppler shifted harmonic components from each said reflected signal; a range determining device, responsive to the amplitudes of said harmonic components, for determining the instantaneous range of said object from each said transducer device; a velocity measurement device, responsive to the frequency of said harmonic components, for determining the relative instantaneous velocity of said object; and an impact decision device, responsive to said range determining device and the velocity measurement device, for determining where, if at all, impact with the object will occur and the angle of the impact prior to impact with the object.

Claims

1. A multi-sensor anticipatory object detection system for detecting the instantaneous range, relative velocity, collision angle and point of impact of a colliding object comprising:

a plurality of transducer devices spaced a fixed distance in which each said transducer device transmits a modulated carrier signal and receives the reflected modulated carrier signal from an object;

a detection device for detecting a plurality of Doppler shifted harmonic components from each said reflected signal;

a range determining device, responsive to the amplitudes of said harmonic components, for determining the instantaneous range of said object from each said transducer device;

a velocity measurement device, responsive to the frequency of said harmonic components, for determining the relative instantaneous velocity of said object; and

an impact decision device, responsive to said range determining device and said velocity measurement device, for determining where, if at all, impact on the vehicle with said object will occur and the angle of said impact prior to impact with said object.

2. The multi-sensor anticipatory object detecting system of claim 1 in which said plurality of transducer devices includes at least a first transducer device for receiving a first reflected modulated carrier signal having a first modulation signal and a second transducer device for receiving a second reflected modulated carrier signal having a second modulation signal.

3. The multi-sensor anticipatory object detection system of claim 2 in which said velocity measurement device includes:

a first velocity measurement circuit, responsive to the frequency of said first modulation signal for determining a first relative velocity between said object and said first transducer device; and

a second velocity measurement circuit, responsive to the frequency of said second modulation signal, for determining a second relative velocity between said object and said second transducer device.

4. The multi-sensor anticipatory object detection system of claim 3 in which said first velocity measurement circuit includes a first comparator device, responsive to one of said plurality of harmonic components of said first modulation signal, for providing a first Doppler pulse each time the amplitude of said harmonic component exceeds a predetermined level for monitoring said first relative velocity between said object and said first transducer device.

5. The multi-sensor anticipatory object detection system of claim 4 in which said second velocity measurement circuit includes a second comparator device, responsive to one of said plurality of harmonic components of said second modulation signal, for providing a second Doppler pulse each time the amplitude of said harmonic component exceeds a predetermined level for monitoring said second relative velocity between said object and said second transducer device.

6. The multi-sensor anticipatory object detection system of claim 5 in which said range determining device includes first detection means, responsive to the amplitudes of the harmonic components of said first modulation signal, for detecting the occurrence of a first predetermined relationship between said harmonic components to determine a first range of said object from said first transducer device.

7. The multi-sensor anticipatory object detection system of claim 6 in which said range determining device further includes second detection means, responsive to the amplitudes of the harmonic components of said second modulation signal, for detecting the occurrence of a second predetermined relationship between said harmonic components to determine a second range of said object from said second transducer.

8. The multi-sensor anticipatory object detection system of claim 7 in which said impact decision device includes counting means, responsive to said occurrence of said first predetermined relationship, for counting said first Doppler pulses until said occurrence of said second predetermined relationship for indicating a third range of said object from said first transducer device.

9. The multi-sensor anticipatory object detection system of claim 8 in which said impact decision device further includes a calculation device, said calculation device including first calculation means, responsive to said second range, said third range and said fixed distance, for determining the angle between said automobile and the heading of said object to said first transducer device.

10. The multi-sensor anticipatory object detection system of claim 9 in which said calculation device further includes second calculation means, responsive to said first calculation means, for determining the angle between the heading of said object to said second transducer device and said heading to said first transducer device.

11. The multi-sensor anticipatory object detection system of claim 10 in which said calculation device further includes third calculation means, responsive to said first relative velocity, said second relative velocity, said first calculation means and said second calculation means, for determining the velocity of said object relative to said automobile, said velocity including a normal component and a tangential component.

12. The multi-sensor anticipatory object detection system of claim 11 in which said calculation device further includes fourth calculation means, responsive to said third calculation means, for determining said angle of impact.

13. The multi-sensor anticipatory object detection system of claim 12 in which said calculation device further includes fifth calculation means, responsive to said third range, said first calculation means, said angle of impact and said fixed distance, for determining said point of impact.

14. The multi-sensor anticipatory object detection system of claim 7 in which said impact decision device includes a calculation device, responsive to said occurrence of said first predetermined relationship and said occurrence of said second predetermined relationship for determining the point of impact of said object.

15. The multi-sensor anticipatory object detection system of claim 14 in which said calculation device includes means, responsive to said first relative velocity and said second relative velocity, for determining the normal component of said relative instantaneous velocity of said object.

16. The multi-sensor anticipatory object detection system of claim 15 in which said calculation device further includes means, responsive to said normal component, for determining the angle of said impact.

17. The multi-sensor anticipatory object detection system of claim 16 in which said calculation device further includes impact means, responsive to said angle of impact, for determining the point of said impact of said object.

18. The multi-sensor anticipatory object detection system of claim 17 in which said impact means includes a lookup table for outputting the location of said point of impact in response to said angle of impact.

19. The multi-sensor anticipatory object detection system of claim 18 in which said first detection means includes means for detecting whether the amplitude of one of said harmonic components of said first modulation signal exceeds a predetermined threshold value and said second detection means includes means for detecting whether the amplitude of one of said harmonic components of said second modulation signal exceeds said predetermined value.

20. The multi-sensor anticipatory object detection system of claim 19 in which said first detection means further includes means for detecting when the difference in amplitude between said one of said harmonic components relative to the amplitude of another of said harmonic components of said first modulation signal exceeds a second threshold value and said second detection means further includes means for detecting when the difference in amplitude between said one of said harmonic components relative to the amplitude of another of said harmonic components of said second modulation signal exceeds said second threshold value.

21. The multi-sensor anticipatory object detection system of claim 20 in which said first predetermined relationship occurs when said one of said harmonic components equals said another of said harmonic components of said first modulation signal and said second predetermined relationship occurs when said one of said harmonic components equals said another of said harmonic components of said second modulation signal.

22. The multi-sensor anticipatory object detection system of claim 21 in which said first detection means further includes means for detecting the difference in amplitude between said one of said harmonic components and yet another of said harmonic components of said first modulation signal and said second detection means further includes means for detecting the difference in amplitude between said one of said harmonic components and yet another of said harmonic components, of said second modulation signal.

23. The multi-sensor anticipatory object detection system of claim 22 in which said first detection means includes means, responsive to one of said harmonic components of said first modulation signal, for determining the time to the occurrence of a third predetermined relationship between the amplitudes of at least two of said harmonic components of said first modulation signal.

24. The multi-sensor anticipatory object detection system of claim 23 in which said second detection means includes means, responsive to one of said harmonic components of said second modulation signal, for determining the time to the occurrence of a fourth predetermined relationship between the amplitudes of at least two of said harmonic components of said second modulation signal.

25. The multi-sensor anticipatory object detection system of claim 24 in which said impact decision device further includes means, responsive the occurrence of said third predetermined relationship and said fourth predetermined relationship, for determining that impact with said object will occur and the time of impact prior to impact with said object.

26. The multi-sensor anticipatory object detection system of claim 25 in which said one of said harmonic components of said first modulation signal is the second harmonic component and said one of said harmonic components of said second modulation signal is the second harmonic component.

27. The multi-sensor anticipatory object detection system of claim 26 in which said another of said harmonics component of said first modulation signal is the first harmonic component and said another of said harmonic components of said second modulation signal is the first harmonic component.

28. The multi-sensor anticipatory object detection system of claim 27 in which said yet another of said harmonic components of said first modulation signal is the DC component and said yet another of said harmonic components of said second modulation signal is the DC component.

29. The multi-sensor anticipatory object detection system of claim 5 in which said first velocity measurement circuit further includes:

a first counting circuit, responsive to said first Doppler pulse, for accumulating a number of clock pulses for a period of time defined by said first Doppler pulse; and

a first velocity calculation device, responsive to said first counting circuit, for determining said first relative velocity of said object.

30. The multi-sensor anticipatory object detection system of claim 29 in which said second velocity measurement circuit further includes:

a second counting circuit, responsive to said second Doppler pulse, for accumulating a number of clock pulses for a period of time defined by said second Doppler pulse; and

a second velocity calculation device, responsive to said second counting circuit, for determining said second relative velocity of said object.

31. The multi-sensor anticipatory object detection system of claim 30 in which said range determining device further includes a counter device, responsive to said first counting circuit, for counting said first Doppler pulse for a predetermined period of time after said occurrence of said first predetermined relationship for indicating the instantaneous distance between said first transducer device and said object.

32. The multi-sensor anticipatory object detection system of claim 31 in which said range determining device further includes a counter device, responsive to said second counting circuit, for counting said second Doppler pulse for a predetermined period of time after said occurrence of said second predetermined relationship for indicating the instantaneous distance between said second transducer device and said object.

33. The multi-sensor anticipatory object detection system of claim 1 in which each said transducer device includes a voltage controlled oscillator for producing a carrier signal, a modulation circuit for generating a modulation signal and mixing means for mixing said carrier signal and said modulation signal to provide said modulated carrier signal.

34. The multi-sensor anticipatory object detection system of claim 33 in which said carrier signal has a bandwidth of 100 MHz.

35. The multi-sensor anticipatory object detection system of claim 34 in which said detection device includes a plurality of channels, each said channel extracting one of a plurality of harmonic components from each said modulation signal.

36. The multi-sensor anticipatory object detection system of claim 35 in which each of said plurality of channels includes a pulse shaping circuit.

37. The multi-sensor anticipatory object detection system of claim 36 in which each of said plurality of channels includes an amplifier circuit for varying the amplitude of the harmonic components thereby adjusting the relationship between the harmonic components relative to each other for each said modulation signal.

38. The multi-sensor anticipatory object detection system of claim 37 in which said pulse shaping circuit includes means for rectifying each said harmonic component.

39. The multi-sensor anticipatory object detection system of claim 35 in which at least one of said plurality of channels extracts the Doppler of the DC component of each said modulation signal.

40. The multi-sensor anticipatory object detection system of claim 35 in which at least one of said plurality of channels extracts the Doppler of the first harmonic component of each said modulation signal.

41. The multi-sensor anticipatory object detection system of claim 35 in which at least one of said plurality of channels extracts the Doppler of the second harmonic component of each said modulation signal.