METHOD AND APPARATUS FOR DETECTING ROLLOVER OF AN AUTOMOTIVE VEHICLE BASED ON A LATERAL KINETIC ENERGY RATE THRESHOLD

• US 20060178808A1
• Filed: 02/08/2005
• Published: 08/10/2006
• Est. Priority Date: 02/08/2005
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Subbian, Thiag, Wu, Fubang, Chou, Cliff
• Granted Patent: US 7,702,440 B2
• Time in Patent Office: Days
• US Class Current: 701/124
• CPC Class Codes: B60T 2230/03 Overturn, rollover
• CPC Class Codes: G01M 1/122 Determining position of centre of gravity

Abstract

A rollover sensing system (12) that may be used in the determination of when to deploy restraints in the vehicle. The rollover sensing system (12) may include lateral acceleration sensors (32), a roll rate sensor (18), and a roll angle detector (20). A control circuit (16) determines a roll moment of inertia as a function of the lateral acceleration, a trip point length as a function of the lateral acceleration and a trip point angle as a function of the lateral acceleration. The control circuit (16) determines a rollover threshold in response to the roll rate signal, the roll angle signal, the trip point length, the roll moment of inertia, and the trip point length. The control circuit generates a control signal for the deployment circuit in response to the rollover threshold.

Claims

1. A rollover sensing system comprising:

a lateral acceleration sensor generating a lateral acceleration signal;

a roll rate sensor generating a roll rate signal;

a roll angle detector generating a roll angle signal; and

a control circuit coupled to the roll rate sensor and the lateral acceleration sensor, said control circuit determining a trip point length as a function of the lateral acceleration signal, said control circuit determining a rollover threshold in response to said roll rate signal, said roll angle signal, said trip point length and said roll moment of inertia, said control circuit generating a control signal in response to the threshold.

2. A system as recited in claim 1 wherein said control circuit determines a trip point angle as a function of the lateral acceleration, said control circuit determining a rollover threshold in response to said roll rate signal, said roll angle signal, said trip point length, and said trip point angle.

3. A system as recited in claim 1 wherein said control circuit determines a roll moment of inertia as a function of the lateral acceleration, said control circuit determining a rollover threshold in response to said roll rate signal, said roll angle signal, said roll moment of inertia, and said trip point length.

4. A system as recited in claim 1 wherein a control circuit determines a roll moment of inertia as a function of the lateral acceleration, a trip point length as a function of the lateral acceleration and a trip point angle as a function of the lateral acceleration, said control circuit determining a rollover threshold in response to said roll rate signal, said roll angle signal, said trip point length, said roll moment of inertia, and said trip point angle.

5. A system as recited in claim 1 wherein said roll angle and said roll rate are independently determined.

6. A system as recited in claim 1 wherein said roll angle and said roll rate are determined from the roll rate sensor signal.

7. An occupant restraint system comprising:

an occupant restraint;

a deployment circuit coupled to said occupant restraint;

a lateral acceleration sensor generating a lateral acceleration signal;

a roll rate sensor generating a roll rate signal;

a roll angle detector generating a roll angle signal; and

a control circuit coupled to the roll rate sensor and the lateral acceleration sensor, said control circuit determining a roll moment of inertia as a function of the lateral acceleration, a trip point length as a function of the lateral acceleration and a trip point angle as a function of the lateral acceleration, said control circuit determining a rollover threshold in response to said roll rate signal, said roll angle signal, said trip point length, said roll moment of inertia, and said trip point length, said control circuit generating a control signal for the deployment circuit in response to the threshold.

8. An occupant restraint system as recited in claim 7 wherein said roll angle and said roll rate are independently determined.

9. An occupant restraint system as recited in claim 7 wherein said roll angle and said roll rate are determined from the roll rate sensor signal.

10. An occupant restraint system as recited in claim 7 wherein said occupant restraint is selected from the group consisting of:

an inflatable curtain, side airbag, a driver side front airbag, a passenger side airbag, a retractor and a side airbag.

11. An occupant restraint system as recited in claim 7 wherein said predetermined rollover threshold is energy-based.

12. An occupant restraint system as recited in claim 7 wherein said rollover threshold is a time to fire.

13. An occupant restraint system as recited in claim 7 wherein said energy threshold is a function of a gap requirement.

14. A method of detecting rollover in a vehicle comprising:

determining a lateral acceleration of the vehicle;

determining a roll rate of the vehicle;

determining a roll angle of the vehicle;

determining a trip point length as a function of the lateral acceleration;

determining a rollover threshold in response to said roll rate signal, said roll angle signal, said trip point length and said roll moment of inertia; and

generating a control signal in response to the rollover threshold.

15. A method as recited in claim 14 further comprising determining a roll moment of inertia as a function of the lateral acceleration;

determining a trip point length as a function of the lateral acceleration;

wherein determining a rollover threshold comprises determining the rollover threshold in response to said roll rate signal, said roll angle signal, said trip point length, said roll moment of inertia, said control circuit.

16. A method as recited in claim 14 further comprising determining a trip point length as

a function of the lateral acceleration;

determining a trip point angle as a function of the lateral acceleration;

wherein determining a rollover threshold comprises determining the rollover threshold in response to said roll rate signal, said roll angle signal, said trip point length and said trip point angle.

17. A method as recited in claim 14 further comprising determining a roll moment of

inertia as a function of the lateral acceleration;

determining a trip point length as a function of the lateral acceleration;

determining a trip point angle as a function of the lateral acceleration;

wherein determining a rollover threshold comprises determining the rollover threshold in response to said roll rate signal, said roll angle signal, said trip point length, said roll moment of inertia, and said trip point angle.

18. A method of detecting rollover as recited in claim 14 wherein said rollover threshold is a function of gap.

19. A method of detecting rollover as recited in claim 18 wherein determining lateral acceleration comprises determining lateral acceleration from a side impact accelerometer.

20. A method of detecting rollover as recited in claim 18 wherein said roll angle and roll rate are independently determined.