Fast sensing system and method for soil- and curb-tripped vehicle rollovers

• US 7,996,132 B2
• Filed: 11/06/2008
• Issued: 08/09/2011
• Est. Priority Date: 11/29/2007
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH, Robert Bosch LLC (Robert Bosch GmbH)
• Original Assignee: Robert Bosch GmbH
• Inventors: Park, Seo-Wook
• Primary Examiner(s): Ilan; Ruth
• Application Number:
  US12/265,896
• Publication Number:
  US 20090143944A1
• Time in Patent Office: 1,006 Days
• Field of Search: 701/45, 701/46, 180/282, 280/735
• US Class Current: 701/46
• CPC Class Codes: B60R 2021/0018 Roll-over
• CPC Class Codes: B60R 2021/01322 comprising variable thresholds, e.g. depending from other collision parameters
• CPC Class Codes: B60R 2021/01327 Angular velocity or angular acceleration
• CPC Class Codes: B60R 21/0132 responsive to vehicle motion parameters , e.g. to vehicle longitudinal or transversal deceleration or speed value
• CPC Class Codes: B60R 21/0133 by integrating the amplitude of the input signal
• CPC Class Codes: B60R 21/01336 using filtering

Abstract

A method and a system of controlling a restraint device in a vehicle during a crash. The method includes sensing a lateral acceleration without using other vehicle dynamic information. The method also includes integrating the sensed lateral acceleration to determine a change in (or delta of) lateral velocity, low-pass filtering the sensed lateral acceleration, and extrapolating the delta lateral velocity and the filtered acceleration to estimate a vehicle lateral velocity. The method also includes sensing a vertical acceleration, integrating the sensed vertical acceleration, combining the integrated vertical acceleration and the predicted vehicle lateral velocity to give an indication of how severely the vehicle laterally hits an obstacle, and generating a deployment signal to activate the restraint device.

Claims

1. A method of controlling a restraint device in a vehicle during a crash, the method comprising:

sensing a lateral acceleration, a vertical acceleration, and an angular rate of the vehicle;

filtering the lateral acceleration and the angular rate;

integrating the lateral acceleration to obtain a lateral velocity, the vertical acceleration to obtain a vertical velocity, and the angular rate to obtain an angle;

determining a combined velocity based on the lateral acceleration;

classifying the crash based on the combined velocity and the filtered lateral acceleration;

determining a critical lateral acceleration and a critical angular rate for the crash;

comparing the critical lateral acceleration with the filtered lateral acceleration, and the critical angular rate with the filtered angular rate; and

generating a deployment signal to activate the restraint device.

2. The method of claim 1, wherein classifying the crash includes classifying the crash as one of a soil-tripped crash and a curb-tripped crash.

3. The method of claim 2, wherein classifying the crash as one of a soil-tripped crash and a curb-tripped crash includes

comparing the filtered lateral acceleration with a threshold;

assigning the crash as one of a soil-tripped crash and a curb-tripped crash when the filtered lateral acceleration is above the threshold; and

assigning the crash as the other of a soil-tripped crash and a curb-tripped crash when the filtered lateral acceleration is below the threshold.

4. The method of claim 3, wherein the threshold comprises a straight-line threshold.

5. The method of claim 1, further comprising determining a sensitized critical angular rate based on the comparison between the filtered lateral acceleration and the critical lateral acceleration.

6. The method of claim 1, wherein determining the combined velocity comprises:

time-weighing the filtered lateral acceleration; and

summing the time-weighed filtered lateral acceleration, the lateral velocity, and the vertical velocity.

7. The method of claim 1, wherein the combined velocity is used to determine the critical lateral acceleration.

8. The method of claim 1, wherein the angle is used to determine the critical angular rate.

9. The method of claim 1, further comprising calculating a critical angular rate add-on value based on the comparison of the filtered lateral acceleration and the critical lateral acceleration.

10. A method of controlling a restraint device in a vehicle during a crash, the method comprising:

sensing a first acceleration of the vehicle, a second acceleration of the vehicle, and an angular rate of the vehicle;

estimating a first velocity from the first acceleration, a second velocity from the second acceleration, and a roll angle from the angular rate;

calculating a time-weighed acceleration based on the first acceleration;

calculating a combined velocity based on the time-weighed acceleration, the first velocity, and the second velocity;

classifying the crash based on the combined velocity and the first acceleration;

calculating at least one critical acceleration and at least one critical angular rate;

selecting one of the at least one critical accelerations and one of the at least one critical angular rates based on the classification of the crash;

comparing the selected critical acceleration to the first acceleration, and the selected critical angular rate to the angular rate; and

generating a deployment signal when the first acceleration is greater than or equal to the selected critical acceleration, and when the angular rate is greater than or equal to the selected critical angular rate.

11. The method of claim 10, wherein the crash is classified as one of a soil-tripped crash and a curb-tripped crash.

12. The method of claim 11, wherein classifying the crash into one of a soil-tripped crash and a curb-tripped crash comprises:

filtering the first acceleration;

comparing the filtered first acceleration with a threshold;

assigning the crash as one of a soil-tripped crash and a curb-tripped crash when the filtered first acceleration is above the threshold; and

assigning the crash as the other of a soil-tripped crash and a curb-tripped crash when the filtered first acceleration is below the threshold.

13. The method of claim 12, wherein the threshold comprises a straight-line threshold.

14. The method of claim 12, further comprising determining a sensitized critical angular rate based on the comparison between the filtered first acceleration and the selected critical acceleration.

15. The method of claim 12, wherein calculating the combined velocity includes summing the time-weighed acceleration, the first velocity, and the second velocity.

16. The method of claim 12, wherein the combined velocity is used to calculate the at least one critical acceleration.

17. The method of claim 10, wherein the roll angle is used to calculate the at least one critical angular rate.

18. The method of claim 10, further comprising calculating a critical angular rate add-on value based on the comparison of the selected critical acceleration and the first acceleration.

19. A control system for a restraint device in a vehicle, the system comprising:

a lateral acceleration sensor configured to sense a lateral acceleration of the vehicle;

a vertical acceleration sensor configured to sense a vertical acceleration of the vehicle;

an angular rate sensor configured to sense an angular rate of the vehicle;

a first filter configured to filter the lateral acceleration of the vehicle and a second filter configured to filter the angular rate of the vehicle;

a first summing module configured to obtain a lateral velocity, a second summing module configured to obtain a vertical velocity, and a third summing module configured to obtain a roll angle;

a combined velocity module configured to determine a combined velocity of the vehicle based on the lateral acceleration, the lateral velocity, and the vertical velocity;

a decision module configured to classify a crash based on the combined velocity and filtered lateral acceleration;

a critical lateral acceleration module configured to determine a critical lateral acceleration;

a critical angular rate module configured to determine a critical angular rate;

a first comparator configured to compare the critical lateral acceleration with the filtered lateral acceleration, and a second comparator configured to compare the critical angular rate with the filtered angular rate; and

a deployment signal generator configured to generate a deployment signal to activate the restraint device.

20. The system of claim 19, further comprising an add-on value module configured to calculate a critical angular rate add-on value based on the comparison of the critical lateral acceleration and the filtered lateral acceleration.