Vehicle rollover detection system

• US 20030182041A1
• Filed: 03/19/2003
• Published: 09/25/2003
• Est. Priority Date: 03/19/2002
• Status: Active Grant

• Current Assignee: TK Holdings Incorporated (Ningbo Junsheng Investment Group Co., Ltd.)
• Original Assignee: TK Holdings Incorporated (Ningbo Junsheng Investment Group Co., Ltd.)
• Inventors: Watson, W. Todd
• Granted Patent: US 7,057,503 B2
• Time in Patent Office: Days
• US Class Current: 701/45
• 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
• CPC Class Codes: B60W 30/04 related to roll-over prevention
• CPC Class Codes: G01S 17/88 Lidar systems specially adapted for specific applications

Abstract

A roll angular velocity sensor and a lateral velocity sensor are operatively coupled to a processor, which generates a signal for controlling a safety restraint system responsive to measures of roll angular velocity and lateral velocity. In one embodiment, the processor delays or inhibits the deployment of the safety restraint system responsive to a measure responsive to the measure of lateral velocity, either alone or in combination with a measure of longitudinal velocity. In another embodiment, a deployment threshold is responsive to the measure of lateral velocity. The lateral velocity may be measured by a lateral velocity sensor, or estimated responsive to measures of lateral acceleration, vehicle turn radius, and either longitudinal velocity or yaw angular velocity, wherein the turn radius is estimated from either a measure of steering angle, a measure of front tire angle, or measures of forward velocity from separate front wheel speed sensors.

Claims

1. A system for detecting a rollover condition of a vehicle, comprising:

a. a roll angular velocity sensor operatively coupled to the vehicle, wherein said roll angular velocity sensor is adapted to measure a roll rate of the vehicle about a roll axis, and said roll axis is substantially aligned with a longitudinal axis of the vehicle;

b. a lateral velocity sensor operatively coupled to the vehicle, wherein said lateral velocity sensor is responsive to a velocity of the vehicle in a direction that is substantially lateral to said vehicle, and said lateral velocity sensor is selected from an ultrasonic sensor, a microwave sensor, a radar sensor, and an optical velocity sensor; and

c. a processor operatively coupled to said roll angular velocity sensor and to said lateral velocity sensor, wherein said processor is adapted to generate a signal for controlling a safety restraint system, and said signal for controlling said safety restraint system is responsive to a signal from said roll angular velocity sensor and to a signal from said lateral velocity sensor.

2. A system for detecting a rollover condition of a vehicle as recited in claims 1, wherein said processor is adapted to determine a measure of roll angle by integrating said signal from said roll angular velocity sensor, and said signal for controlling said safety restraint system is further responsive to said measure of roll angle.

3. A system for detecting a rollover condition of a vehicle as recited in claims 1, further comprising a longitudinal velocity sensor operatively coupled to the vehicle, wherein said longitudinal velocity sensor is responsive to a velocity of the vehicle in a direction that is substantially along said longitudinal axis of the vehicle, and said signal for controlling said safety restraint system is further responsive to a signal from said longitudinal velocity sensor.

4. A system for detecting a rollover condition of a vehicle as recited in claims 1, further comprising an accelerometer operatively coupled to the vehicle, wherein said accelerometer is adapted to measure an acceleration of the vehicle substantially in said lateral direction, and:

said signal for controlling said safety restraint system is further responsive to a signal from said accelerometer.

5. A method of providing for detecting a rollover condition of a vehicle, comprising:

a. providing for acquiring a measure of roll angular velocity of the vehicle about a roll axis, wherein said roll axis is substantially aligned with a longitudinal axis of the vehicle;

b. providing for acquiring a measure of lateral velocity of the vehicle, wherein said measure of lateral velocity is directly representative of a lateral velocity of the vehicle; and

c. providing for generating a signal for controlling a safety restraint system, wherein said signal for controlling said safety restraint system is responsive to said measure of roll angular velocity and to said measure of lateral velocity.

6. A method of providing for detecting a rollover condition of a vehicle as recited in claim 5, wherein said signal for controlling said safety restraint system is responsive to a deployment threshold, and said deployment threshold is responsive to said measure of lateral velocity.

7. A method of providing for detecting a rollover condition of a vehicle as recited in claim 6, wherein said deployment threshold is shifted by an offset responsive to said measure of lateral velocity.

8. A method of providing for detecting a rollover condition of a vehicle as recited in claim 6, wherein said deployment threshold is scaled by a factor responsive to said measure of lateral velocity.

9. A method of providing for detecting a rollover condition of a vehicle as recited in claim 5, further comprising:

a. providing for comparing a third measure with a first threshold, wherein said third measure is responsive to said measure of lateral velocity; and

b. providing for delaying or inhibiting deployment of said safety restraint system if said third measure is less than said first threshold.

10. A method of providing for detecting a rollover condition of a vehicle as recited in claim 5, further comprising:

a. providing for acquiring a measure of longitudinal velocity of the vehicle;

b. providing for determining a measure of translational velocity of the vehicle, wherein said measure of translational velocity is responsive to said measure of longitudinal velocity and to said measure of lateral velocity;

c. providing for comparing a fourth measure with a second threshold, wherein said fourth measure is responsive to said measure of translational velocity; and

d. providing for inhibiting deployment of said safety restraint system if said fourth measure is less than said second threshold.

11. A method of providing for detecting a rollover condition of a vehicle as recited in claim 5, further comprising:

a. providing for determining or acquiring a measure of roll angle from said measure of roll angular velocity;

b. providing for determining a threshold function in a phase space of said measure of roll angular velocity and said measure of roll angle;

c. providing for modifying said threshold function responsive to said measure of lateral velocity; and

d. providing for comparing a measure in phase space with said threshold function, where said measure in phase space comprises a combination of said measure of roll angular velocity and said measure of roll angle, wherein said signal for controlling said safety restraint system is responsive to the operation of comparing said measure in phase space with said threshold function.

12. A method of providing for detecting a rollover condition of a vehicle as recited in claim 11, wherein said threshold function comprises either a function in phase space, a piecewise function in phase space, or a table lookup in phase space.

13. A method of providing for detecting a rollover condition of a vehicle as recited in claim 11, wherein the operation of modifying said threshold function comprises determining a roll angular velocity offset responsive to said measure of lateral velocity, and subtracting said roll angular velocity offset from said threshold function.

14. A method of providing for detecting a rollover condition of a vehicle as recited in claim 5, further comprising:

a. generating a fifth measure responsive to said measure of lateral velocity and to at least one of a measure selected from the group comprising said measure of roll angular velocity, a measure of roll angle of the vehicle, a measure of lateral acceleration of the vehicle, a measure of vertical acceleration of the vehicle, a measure of steering wheel angle of the vehicle, a measure of longitudinal speed of the vehicle, and a measure of yaw rate of the vehicle;

b. comparing said fifth measure with a third threshold; and

c. controlling said safety restraint system responsive to the operation of comparing said fifth measure with said third threshold.

15. A method of providing for detecting a rollover condition of a vehicle as recited in claim 14, wherein said fifth measure comprises a combination of a lateral translational kinetic energy measure and a measure responsive to said roll rate measure, wherein said lateral translational kinetic energy measure is responsive to said measure of lateral velocity, and said measure responsive to said roll rate measure is responsive to at least one of a rotational kinetic energy measure and a measure of roll angle, wherein said rotational kinetic energy measure is responsive to said measure of roll angular velocity, and said measure of roll angle is responsive to an integration of said measure of angular velocity.

16. A method of providing for detecting a rollover condition of a vehicle as recited in claim 5, wherein the operation of providing for generating said signal for controlling said safety restraint system comprises:

a. providing for acquiring a measure of lateral acceleration of the vehicle;

b. providing for determining a figure of merit responsive to said measure of lateral acceleration and said measure of roll angular velocity;

c. providing for determining a figure of merit threshold responsive to said measure of lateral velocity; and

d. providing for detecting the rollover condition by comparing said figure of merit with said figure of merit threshold.

17. A method of providing for detecting a rollover condition of a vehicle as recited in claim 16, wherein the operation of providing for determining a figure of merit threshold comprises multiplying a first figure of merit threshold by a threshold multiplier, and said threshold multiplier is responsive to said measure of lateral velocity.

18. A method of providing for detecting a rollover condition of a vehicle as recited in claim 16, wherein the operation of providing for determining a figure of merit threshold comprises adding an offset to a first figure of merit threshold, and said offset is responsive to said measure of lateral velocity

19. A method of providing for detecting a rollover condition of a vehicle, comprising:

a. providing for acquiring a measure of roll angular velocity of the vehicle about a roll axis, wherein said roll axis is substantially aligned with a longitudinal axis of the vehicle;

b. providing for acquiring a measure of lateral acceleration of the vehicle;

c. providing for acquiring at least one of a measure of longitudinal velocity of the vehicle and a measure of yaw angular velocity about a yaw axis;

d. providing for determining a measure of a turn radius of the vehicle;

e. providing for determining a measure of lateral velocity of the vehicle responsive to said measure of lateral acceleration, to said measure of said turn radius, and to at least one of said measure of longitudinal velocity and said measure of yaw angular velocity; and

f. providing for generating a signal for controlling said safety restraint system, wherein said signal for controlling said safety restraint system is responsive to said measure of roll angular velocity and to said measure of lateral velocity.

20. A method of providing for detecting a rollover condition of a vehicle as recited in claim 19, wherein the operation of determining a measure of turn radius comprises:

a. acquiring at least one of a measure of steering wheel angle, a measure of a front tire angle, and measures of forward velocity from separate front wheel speed sensors; and

b. determining said measure of turn radius responsive to said at least one of a measure of steering wheel angle, a measure of a front tire angle, and measures of forward velocity from separate front wheel speed sensors.

21. A method of providing for detecting a rollover condition of a vehicle as recited in claim 19, wherein the operation of providing for determining a measure of lateral velocity comprises integrating a fourth measure, wherein said fourth measure is responsive to a difference between said measure of lateral acceleration and a measure of centripetal acceleration, and said measure of centripetal acceleration is responsive to said turn radius, and to at least one of said measure of yaw angular velocity and said measure of longitudinal velocity.

22. A method of providing for detecting a rollover condition of a vehicle as recited in claim 21, further comprising limiting a magnitude of said measure of centripetal acceleration by a centripetal acceleration threshold.

23. A method of providing for detecting a rollover condition of a vehicle as recited in claim 21, wherein said measure of centripetal acceleration comprises a product of said measure of yaw angular velocity and said turn radius.

24. A method of providing for detecting a rollover condition of a vehicle as recited in claim 21, wherein said measure of centripetal acceleration comprises said measure of longitudinal velocity divided by said turn radius.

25. A method of providing for detecting a rollover condition of a vehicle as recited in claim 21, wherein the operation of providing for determining a measure of lateral velocity further comprises:

a. determining a measure of spin rate, wherein said measure of spin rate is responsive to said measure of yaw angular velocity, and to a fifth measure, wherein said fifth measure is responsive to said measure of longitudinal velocity, and to said turn radius;

b. integrating said measure of spin rate so as to generate a measure of spin angle;

c. generating a sixth measure by multiplying said measure of longitudinal velocity times said spin angle; and

d. generating a modified measure of lateral velocity by adding said sixth measure to said measure of lateral velocity.

26. A method of providing for detecting a rollover condition of a vehicle as recited in claim 25, further comprising limiting said fifth measure responsive to a centripetal acceleration threshold and to said measure of longitudinal velocity.