Three dimensional occupant position sensor

• US 20030222440A1
• Filed: 06/03/2002
• Published: 12/04/2003
• Est. Priority Date: 06/03/2002
• Status: Active Grant

• Current Assignee: Appy Risk Technologies Limited (Trak Global Group Ltd.)
• Original Assignee: Intelligent Mechatronic Systems Inc. (Trak Global Group Ltd.)
• Inventors: Kotlyachkov, Michael, Karray, Fakhreddine, Filippov, Vladimir, Basir, Otman Adam
• Granted Patent: US 7,370,883 B2
• Time in Patent Office: Days
• US Class Current: 280/735
• CPC Class Codes: B60R 21/01532 using electric or capacitive field sensors
• CPC Class Codes: B60R 21/01534 using electromagneticwaves, e.g. infrared
• CPC Class Codes: B60R 21/01542 detecting passenger motion

Abstract

This invention describes a roof-mounted sensor consisting of two rows of intersecting electrodes that are placed across an area of the vehicle'"'"'s roof and a method to determine the position and motion of an occupant. This is accomplished by measuring physical values, which depend on the distance between the highest point of an occupant'"'"'s body to each electrode in the row. Analysis of said physical values is used to derive an occupant'"'"'s position relative to each row and the distance between the highest point of an occupant'"'"'s body and the vehicle'"'"'s roof. By analyzing the change in distances with respect to time, the occupant'"'"'s motion can be tracked.

Claims

1. ) A method for determining a position of a vehicle occupant including the steps of:

a. Measuring an electromagnetic field induced by an occupant at a plurality of points in a vehicle passenger compartment; and

b. Calculating a three-dimensional position of the occupant in the passenger compartment using signal distribution based upon said step a.

2. ) The method of claim 1 wherein said step b. further includes the step of using a signal distribution function to calculate the position.

3. ) The method of claim 1 wherein said step b. further includes the step of comparing the electromagnetic field induced at a first one of the plurality of points to the electromagnetic field induced at a second one of the plurality of points.

4. ) The method of claim 3 wherein said step a. further includes the step of transmitting an electromagnetic signal from a vehicle seat in the vehicle passenger compartment.

5. ) The method of claim 4 wherein the plurality of points are arranged substantially in a plane.

6. ) The method of claim 1 further including the steps of:

Storing a calibration signal; and

Determining the position of the occupant in said step b. based upon a comparison of the electromagnetic field measured in said step a. to said calibration signal.

7. ) A vehicle passenger compartment proximity sensing system comprising:

A plurality of sensors measuring capacitance at a plurality of points in a passenger compartment; and

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

8. ) The vehicle passenger compartment proximity sensing system of claim 7 further comprising:

a first electrode generating an electromagnetic signal;

said capacitive sensors comprising a plurality of second electrodes receiving the electromagnetic signal; and

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

9. ) The vehicle passenger compartment proximity sensing system of claim 8 wherein the first electrode is mounted in a vehicle seat in the vehicle passenger compartment.

10. ) The vehicle passenger compartment proximity sensing system of claim 9 wherein the plurality of second electrodes is mounted adjacent a vehicle headliner in the vehicle passenger compartment.

11. ) A computer readable medium containing a computer program which when executed by a computer performs the steps of:

a. Receiving a plurality of measurements of an electromagnetic field induced by an occupant at a plurality of points in a vehicle passenger compartment; and

b. Calculating a three-dimensional position of the occupant in the passenger compartment using signal distribution based upon said plurality of measurements.

12. ) The computer readable medium of claim 11 wherein said step b. further includes the step of using a signal distribution function to calculate the position.

13. ) The computer readable medium of claim 12 wherein said step b. further includes the step of comparing differences among the electromagnetic field induced at the plurality of points.

14. ) The computer readable medium of claim 13 wherein the plurality of points are assumed to be arranged substantially in a plane.

15. ) The computer readable medium of claim 11 further including the step of:

Determining the position of the occupant in said step b. based upon a comparison of the plurality of measurements to a calibration signal.