Roll over stability control for an automotive vehicle having rear wheel steering

• US 20020082749A1
• Filed: 11/05/2001
• Published: 06/27/2002
• Est. Priority Date: 12/21/1999
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Meyers, Joseph Carr, Brown, Todd Allen
• Granted Patent: US 6,529,803 B2
• Time in Patent Office: Days
• US Class Current: 701/1
• CPC Class Codes: B60G 2400/0521 Roll rate
• CPC Class Codes: B60G 2400/0523 Yaw rate
• CPC Class Codes: B60G 2400/104 lateral or transversal with regard to vehicle
• CPC Class Codes: B60G 2400/204 Vehicle speed
• CPC Class Codes: B60G 2400/64 Wheel forces, e.g. on hub, spindle or bearing
• CPC Class Codes: B60G 2800/012 Rolling condition
• CPC Class Codes: B60G 2800/0124 Roll-over conditions
• CPC Class Codes: B60G 2800/215 by applying a braking action on each wheel individually
• CPC Class Codes: B60G 2800/922 EBV - Electronic brake force distribution
• CPC Class Codes: B60T 2230/03 Overturn, rollover
• CPC Class Codes: B60T 2250/06 Sensor zero-point adjustment; Offset compensation
• CPC Class Codes: B60T 7/12 for automatic initiation; for initiation not subject to will of driver or passenger limiting speed of vehicles other than rail vehicles B60K31/00
• 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: B60T 8/17554 specially adapted for enhancing stability around the vehicles longitudinal axle, i.e. roll-over prevention road vehicle drive control systems for roll-over prevention otherwise than by controlling a particular sub-unit B60W30/04
• CPC Class Codes: B60T 8/243 for roll-over protection
• CPC Class Codes: B60W 10/184 with wheel brakes
• CPC Class Codes: B60W 10/20 including control of steering systems
• CPC Class Codes: B60W 2520/18 Roll
• CPC Class Codes: B60W 2552/00 Input parameters relating to infrastructure
• CPC Class Codes: B60W 2556/50 of positioning data, e.g. GPS [Global Positioning System] data
• CPC Class Codes: B60W 2720/18 : Roll
• CPC Class Codes: B60W 30/04 : related to roll-over prevention

Abstract

A stability control system (24) for an automotive vehicle as includes a plurality of sensors (28-39) sensing the dynamic conditions of the vehicle and a controller controls a steering force to reduce a tire moment so the net moment of the vehicle is counter to the roll direction. The sensors may include a speed sensor (30), a lateral acceleration sensor (32), a roll rate sensor (34), a yaw rate sensor (20) and a longitudinal acceleration sensor (36). The controller (26) is coupled to the speed sensor (30), the lateral acceleration sensor (32), the roll rate sensor (34), the yaw rate sensor (28) and a longitudinal acceleration sensor (36). The controller (26) determines a roll angle estimate in response to lateral acceleration, longitudinal acceleration, roll rate, vehicle speed, and yaw rate. The controller (26) changes a tire force vector using by changing the direction and/or force of the steering actuator in response to the relative roll angle estimate.

Claims

1. A stability control system for an automotive vehicle having a front steering system and a rear steering system comprising:

a rear wheel steering actuator;

a rear wheel position sensor generating a rear wheel position signal;

a rollover sensor for producing a rollover signal in response to an impending rollover of the vehicle; and

a controller coupled to said rear wheel steering sensor, said rollover sensor, and

said rear wheel steering actuator, said controller generating a rear wheel steering actuator signal in response to said rollover signal, said rear wheel steering actuator signal controlling said rear steering actuator to prevent the vehicle from rolling over.

2. A stability control system as recited in claim 1 wherein said rollover sensor comprises one or more selected from the group of a lateral acceleration sensor;

a roll rate sensor; and

a load sensor.

3. A stability control system as recited in claim 2 further comprising a sensor selected from the group of a steering angle sensor, a speed sensor, a yaw rate sensor, a longitudinal acceleration sensor and a pitch rate sensor.

4. A stability control system as recited in claim 1 wherein said controller changes a tire force vector by changing a direction and rear steering force of said rear actuator.

5. A stability control system as recited in claim 1 wherein said rear wheel actuator comprises a right wheel actuator and a left wheel actuator.

6. A stability control system as recited in claim 1 wherein said controller changes a tire force vector by changing a direction and rear steering force of said rear actuator.

7. A stability control system as recited in claim 6 wherein said controller changes a tire force vector by changing a relative direction between said right rear actuator and said left rear actuator.

8. A stability control system as recited in claim 1 further comprising a plurality of brake actuators, said controller controlling said brake actuators in response to said rollover signal.

9. A stability control system as recited in claim 1 further comprising a front wheel steering actuator, said controller controlling said front wheel steering in response to said rollover signal.

10. A stability control system as recited in claim 9 further comprising a plurality of brake actuators, said controller controlling said brake actuators in response to said rollover signal.

15. A method as recited in claim 10 further comprising:

sensing the position of a front wheel steering actuator; and

generating the tire moment counter to the roll direction by controlling the front wheel steering actuator in response to said impending rollover and said position of the front wheel steering actuator.

16. A method as recited in claim 10 wherein the step of generating comprises controlling a brake.

11. A method of controlling roll stability of a vehicle rear wheel steering actuator comprising:

sensing the position of the rear wheel steering actuator;

sensing an impending rollover; and

generating a tire moment counter to a roll direction by controlling the rear wheel steering actuator in response to said impending rollover and said position of the rear wheel steering actuator.

12. A method as recited in claim 11 wherein said vehicle comprises a right rear actuator and a left rear actuator and said step of generating comprises generating a tire moment by changing a relative direction between said right rear actuator and said left rear actuator.

13. A method as recited in claim 11 wherein said step of sensing an impending rollover comprises at least one step selected from the group of:

determining a roll rate for the vehicle;

determining a lateral acceleration for the vehicle;

determining a relative load at one corner of the vehicle.

17. A method as recited in claim 14 wherein said vehicle comprises a right rear actuator and a left rear actuator and said step of generating comprises generating a tire moment by changing a relative direction between said right rear actuator and said left rear actuator.

18. A method as recited in claim 14 wherein said step of determining a roll angle estimate comprises at least one step selected from the group of:

determining a roll rate for the vehicle;

determining a lateral acceleration for the vehicle;

determining a relative load at one corner of the vehicle.

19. A method as recited in claim 14 wherein controlling comprises controlling the rear actuator and a front actuator to change the tire force vector in response to the relative roll angle estimate.

20. A method as recited in claim 14 wherein controlling comprises controlling the rear actuator, a front actuator and a brake actuator to change the tire force vector in response to the relative roll angle estimate.

21. A method as recited in claim 14 wherein controlling comprises controlling the rear actuator and a brake actuator to change the tire force vector in response to the relative roll angle estimate.

14. A method of controlling roll stability of a vehicle having a rear steering system comprising the steps of:

determining a roll angle estimate in response to a rollover sensor; and

controlling a rear steering actuator to change a tire force vector in response to the relative roll angle estimate.