Vehicle occupant proximity sensor

• US 20030122554A1
• Filed: 02/18/2003
• Published: 07/03/2003
• Est. Priority Date: 09/29/2000
• Status: Active Grant

• Current Assignee: Appy Risk Technologies Limited (Trak Global Group Ltd.)
• Original Assignee: Fakhreddine Karray, Otman Adam Basir, Vladimir Filippov
• Inventors: Karray, Fakhreddine, Filippov, Vladimir, Basir, Otman Adam
• Granted Patent: US 6,693,442 B2
• Time in Patent Office: Days
• US Class Current: 324/662
• CPC Class Codes: B60R 21/01532 using electric or capacitive field sensors
• CPC Class Codes: B60R 21/01538 for image processing, e.g. cameras or sensor arrays

Abstract

A vehicle occupant proximity sensor includes a transmitting electrode in a vehicle seat and an array of receiving electrodes mounted in a vehicle headliner above the vehicle seat. The sensor determines the capacitance at each of the receiving electrodes, which varies based upon the proximity of the occupant to each receiving electrode, thus producing an array of proximity information indicating in two dimensions the position of the occupant.

Claims

1. A method for activating a vehicle occupant safety system including the steps of:

a. Determining a position of a head of the occupant relative to the safety system; and

b. Determining whether to activate the vehicle occupant safety system based upon said step a.

2. The method of claim 1 wherein said step a. further includes the step of measuring capacitance of the head.

3. The method of claim 2 wherein said step a. further includes the step of measuring capacitance at each of a plurality of points to determine the position of the head in said step a.

4. The method of claim 1 wherein said step a. further includes the step of receiving an electromagnetic signal at a plurality of points in a headliner of a vehicle.

5. The method of claim 1 further including the step of:

c. determining the position of the head in said step a. for each of a plurality of sequential times;

d. analyzing the position of the head over time based upon said step c.; and

e. performing said step b. based upon said step d. over time.

6. A method for activating a vehicle occupant safety system including the steps of:

a. Measuring capacitance at each of a plurality of points in a vehicle passenger compartment having an occupant safety system;

b. Determining a position of an occupant relative to the safety system based upon said step a; and

c. Determining whether to activate the vehicle occupant safety system based upon said step a.

7. The method of claim 6 wherein said step a. further includes the step of transmitting an electromagnetic signal from a vehicle seat in the vehicle passenger compartment.

8. The method of claim 7 wherein said step a. further includes the step of measuring capacitance based upon the electromagnetic signal received at the plurality of points.

9. The method of claim 6 wherein said step a. further includes the step of measuring capacitance at an array of the plurality of points.

10. The method of claim 9 wherein said step a. further includes the step of comparing the capacitance measured at each of the plurality of points with each other.

11. The method of claim 10 wherein the plurality of points are adjacent a headliner in the vehicle passenger compartment.

12. The method of claim 11 wherein said step a. further includes the step of:

d) monitoring a change in capacitance over time at the plurality of points; and

e) in said step c), determining whether to activate the vehicle occupant safety system based upon said step d).

13. A method for activating a vehicle occupant safety system including the steps of:

a. Sensing a proximity of an occupant from each of a plurality of points in a vehicle passenger compartment having an occupant safety system; and

b. Determining a position of an occupant relative to the safety system based upon said step a.

14. The method of claim 13 further including the step of:

c. determining whether to activate the vehicle occupant safety system based upon said step a.

15. The method of claim 14 further including the step of:

d. determining a position of a seat in the vehicle passenger compartment; and

e. determining whether to activate the vehicle occupant safety system in said step c. based upon said step d.

16. The method of claim 13 wherein the plurality of points are an array of said plurality of points.

17. The method of claim 13 further including the step of comparing each of the plurality of points to determine position in said step b.

18. The method of claim 13 further including the step of analyzing the array of said plurality of points as an image.

19. A vehicle passenger compartment proximity sensing system comprising:

A capacitive sensor array measuring capacitance at a plurality of points in a passenger compartment; and

A controller determining a position of an occupant based upon the capacitance measured at the plurality of points.

20. The vehicle passenger compartment proximity sensing system of claim 19 further comprising:

A first electrode generating an electromagnetic signal;

Said capacitive sensor array comprising a plurality of second electrodes receiving the electromagnetic signal; and

the controller determining capacitance at each of the second electrodes to determine the position of the occupant in the vehicle passenger compartment.

21. The vehicle passenger compartment proximity sensing system of claim 20 wherein the first electrode is mounted in a vehicle seat in the vehicle passenger compartment.

22. The vehicle passenger compartment proximity sensing system of claim 21 wherein the array of second electrodes is mounted adjacent a vehicle headliner in the vehicle passenger compartment.