Airbag Deployment Control Using Seatbelt-Mounted Sensor

• US 20080042409A1
• Filed: 10/26/2007
• Published: 02/21/2008
• Est. Priority Date: 06/07/1995
• Status: Active Grant

• Current Assignee: American Vehicular Sciences LLC (Acacia Research Corporation)
• Original Assignee: Automotive Technologies International Incorporated
• Inventors: Breed, David
• Granted Patent: US 7,988,190 B2
• Time in Patent Office: Days
• US Class Current: 280/735
• CPC Class Codes: B60R 2021/01211 Expansion of air bags
• CPC Class Codes: B60R 2022/4808 Sensing means arrangements therefor
• CPC Class Codes: B60R 21/0134 responsive to imminent contact with an obstacle , e.g. using radar systems
• CPC Class Codes: B60R 21/01544 detecting seat belt parameters, e.g. length, tension or height-adjustment

Abstract

Method and system for controlling inflation of an airbag in a vehicle which protects an occupant from injury in a crash involving the vehicle includes sensing a crash involving the vehicle for which deployment of the airbag is desired, inflating the airbag to protect the occupant in the crash involving the vehicle upon sensing of the crash, incorporating an accelerometer in a seatbelt worn by the occupant, and adjusting the continued inflation of the airbag after contact of the airbag with the occupant based on the acceleration sensed by the accelerometer. The accelerometer may be arranged to determine movement or acceleration of the seatbelt which can be correlated to contact between the airbag and the seatbelt, i.e., based on changes in the measured acceleration of the seatbelt arising from contact of the airbag with the seatbelt.

Claims

1. A method for controlling inflation of an airbag in a vehicle which protects an occupant from injury in a crash involving the vehicle, comprising:

sensing a crash involving the vehicle for which deployment of the airbag is desired;

inflating the airbag to protect the occupant in the crash involving the vehicle upon sensing of the crash;

incorporating a sensor in a seatbelt worn by the occupant; and

adjusting the continued inflation of the airbag after contact of the airbag with the occupant based on data provided by the sensor.

2. The method of claim 1, wherein the sensor is an accelerometer arranged to measure acceleration of the seatbelt.

3. The method of claim 2, wherein the measured acceleration of the seatbelt correlates to acceleration of the occupant and contact between the airbag and the seatbelt is determined based on changes in the measured acceleration of the seatbelt arising from contact of the airbag with the seatbelt.

4. The method of claim 1, wherein the adjustment of the continued inflation of the airbag is control of outflow of inflation fluid from the airbag.

5. The method of claim 4, further comprising controlling the outflow of the inflation fluid to maintain the occupant'"'"'s chest acceleration below a threshold, the occupant chest acceleration corresponding to the deceleration of the airbag.

6. The method of claim 5, further comprising:

forecasting the severity of the crash; and

setting the threshold based on the forecast severity.

7. The method of claim 1, further comprising:

determining if the occupant is wearing a seatbelt; and

when the occupant is determined to be wearing a seatbelt, reducing outflow of inflation fluid from the airbag.

8. The method of claim 1, wherein the sensor is a pressure sensor.

9. A method for controlling inflation of an airbag in a vehicle which protects an occupant from injury in a crash involving the vehicle, comprising:

sensing a crash involving the vehicle for which deployment of the airbag is desired;

inflating the airbag to protect the occupant in the crash involving the vehicle upon sensing of the crash;

arranging a sensor in connection with the seatbelt to obtain information about a reaction of the seatbelt to contact with the airbag during inflation of the airbag; and

adjusting the continued inflation of the airbag after contact of the airbag with the seatbelt based on the information obtained by the sensor.

10. The method of claim 9, wherein the adjustment of the continued inflation of the airbag is control of outflow of inflation fluid from the airbag.

11. The method of claim 10, further comprising controlling the outflow of the inflation fluid to maintain the occupant'"'"'s chest acceleration below a threshold, the occupant chest acceleration corresponding to the deceleration of the airbag.

12. The method of claim 11, further comprising:

forecasting the severity of the crash; and

setting the threshold based on the forecast severity.

13. The method of claim 9, wherein the sensor is an accelerometer arranged to measure acceleration of the seatbelt.

14. The method of claim 13, wherein the measured acceleration of the seatbelt correlates to acceleration of the occupant and contact between the airbag and the seatbelt is determined based on changes in the measured acceleration of the seatbelt arising from contact of the airbag with the seatbelt.

15. The method of claim 9, further comprising:

determining if the occupant is wearing a seatbelt; and

when the occupant is determined to be wearing a seatbelt, reducing outflow of inflation fluid from the airbag.

16. A system for protecting an occupant from injury in a crash involving the vehicle, comprising:

an inflatable airbag arranged to inflate to protect the occupant from injury during the crash;

a crash sensor system arranged to sense a crash involving the vehicle for which inflation of said airbag is desired;

an airbag inflation system coupled to said crash sensor system and arranged to initiate inflation of said airbag to protect the occupant in the crash involving the vehicle upon sensing of the crash by said crash sensor system; and

a deployment control system arranged to adjust continued inflation of said airbag after contact of said inflating airbag with the occupant based on contact between said airbag and the occupant.

17. The system of claim 16, wherein said deployment control system includes a sensor arranged in connection with a seatbelt to obtain data relating to movement of said airbag which is analyzed to determine contact between said airbag and the seatbelt during inflation of said airbag.

18. The system of claim 17, wherein said sensor is an accelerometer arranged to measure acceleration of the seatbelt and senses contact between said airbag and the seatbelt based on changes in the measured acceleration of said seatbelt arising from contact of said airbag with the seatbelt.

19. The system of claim 17, wherein said sensor is a pressure sensor.