SUSPENSION IRREGULARITY DETECTING SYSTEM

• US 20070067080A1
• Filed: 09/15/2006
• Published: 03/22/2007
• Est. Priority Date: 10/15/2004
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Messih, David, Lu, Jianbo, Chubb, Erik, Salib, Albert
• Granted Patent: US 7,729,829 B2
• Time in Patent Office: Days
• US Class Current: 701/37
• 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: B60T 2230/03 Overturn, rollover
• CPC Class Codes: B60T 2240/06 Wheel load; Wheel lift
• CPC Class Codes: B60T 8/172 Determining control parameters used in the regulation, e.g. by calculations involving measured or detected parameters B60T8/17551 takes precedence
• CPC Class Codes: B60W 10/18 including control of braking systems
• CPC Class Codes: B60W 10/20 including control of steering systems
• CPC Class Codes: B60W 10/22 including control of suspension systems
• CPC Class Codes: B60W 40/11 Pitch movement
• CPC Class Codes: B60W 40/112 Roll movement
• CPC Class Codes: B60W 40/114 Yaw movement

Abstract

A vehicle suspension system (19) includes a suspension (47). A lateral acceleration sensor (32) generates a lateral acceleration signal. A roll rate sensor (34) generates a roll rate signal. A controller (26) detects an irregularity in the suspension in response to the lateral acceleration signal and the roll rate signal. A method of detecting suspension irregularities in a vehicle (10) includes the generating of a lateral acceleration signal and a roll rate signal. Roll angle is determined in response to the lateral acceleration signal and roll rate signal. A roll gradient, a roll acceleration coefficient, and a roll damping parameter are determined in response to at least the roll angle. The roll gradient, the roll acceleration coefficient, and the roll damping parameter are compared to associated nominal values. A suspension irregularity is indicated in response to the comparison.

Claims

1. A vehicle suspension system comprising:

a suspension;

a lateral acceleration sensor generating a lateral acceleration signal;

a roll rate sensor generating a roll rate signal; and

a controller detecting at least one irregularity in said suspension in response to said lateral acceleration signal and said roll rate signal.

3. A system as in claim 1 wherein said controller in detecting at least one irregularity determines a roll gradient, a roll acceleration coefficient, and a roll damping parameter.

4. A system as in claim 1 wherein said controller in detecting at least one irregularity compares said roll gradient, said roll acceleration coefficient, and said roll damping parameter to nominal values associated therewith.

6. A system as in claim 1 wherein said controller adjusts brake pressure associated with at least one wheel of the vehicle in response to said at least one irregularity.

7. A system as in claim 1 wherein said controller adjusts steering angle of the vehicle in response to said at least one irregularity.

8. A system as in claim 1 wherein said controller adjusts engine power in response to said at least one irregularity.

9. A system as in claim 1 wherein said controller adjusts suspension system damping associated with at least one wheel of the vehicle in response to said at least one irregularity.

2. A system as in claim l wherein said controller in detecting at least one irregularity determines at least one parameter selected from a roll gradient, a roll acceleration coefficient, and a roll damping parameter.

5. A system as in claim I wherein said controller in detecting at least one irregularity detects irregular damping in said suspension.

10. A suspension system for a vehicle comprising:

a suspension;

a lateral acceleration sensor generating a lateral acceleration signal;

a roll rate sensor generating a roll rate signal;

an active system; and

a controller detecting at least one irregularity in said suspension in response to said lateral acceleration signal and said roll rate signal, said controller signaling said active system in response to said at least one irregularity.

11. A system as in claim 10 wherein said controller in detecting at least one irregularity detects a damping irregularity.

12. A system as in claim 10 wherein said controller in detecting a damping irregularity applies brake pressure to outside wheels of the vehicle.

13. A system as in claim 10 wherein said controller in detecting a damping irregularity increases damping for front and rear wheels of the vehicle.

14. A method of detecting suspension irregularities in a vehicle comprising:

generating a lateral acceleration signal;

generating a roll rate signal;

determining roll angle in response to said lateral acceleration signal and said roll rate signal;

determining a roll gradient, a roll acceleration coefficient, and a roll damping parameter in response to said roll angle;

comparing said roll gradient, said roll acceleration coefficient, and said roll damping parameter to associated nominal values; and

indicating at least one suspension irregularity in response to said comparison.

15. A method as in claim 14 further comprising performing a task via an active system to compensate for at least one suspension irregularity.

16. A method as in claim 14 wherein indicating said suspension irregularity a damping characteristic associated with at least one wheel of the vehicle is indicated.

17. A method as in claim 16 wherein said suspension irregularity is indicated to a vehicle operator.

18. A method as in claim 14 wherein determining said roll gradient, said roll acceleration coefficient, and said roll damping parameter comprises a least-squares method.

19. A method as in claim 14 wherein determining said roll gradient, said roll acceleration coefficient, and said roll damping parameter comprises a data averaging method.

20. A method as in claim 14 further comprising determining a cause of said at least one suspension irregularity.