ROLL STABILITY CONTROL AND ROLL-OVER MITIGATION BY STEERING ACTUATION

• US 20080109135A1
• Filed: 11/08/2007
• Published: 05/08/2008
• Est. Priority Date: 11/08/2006
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Jacobson, Bengt, Lemmen, Markus, Vliem, Edwin, Eidam, Dirk-Uwe, Wey, Torsten, Hulten, Johan
• Granted Patent: US 8,620,528 B2
• Time in Patent Office: Days
• US Class Current: 701/41
• 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: B62D 6/002 computing target steering angles for front or rear wheels B62D7/159 takes precedence
• CPC Class Codes: B62D 6/006 using a measured or estimated road friction coefficient

Abstract

The invention relates to a method for reducing a risk of or avoiding a roll-over event of a vehicle, having means of an electronic controllable steering system and an electronic control unit. The electronic control unit identifies the occurrence of the roll-over risk, such that control means generate a signal in order to steer the road wheels more into the direction in which the vehicle is tending to roll-over.

Claims

1. A method for reducing a risk of or avoiding a roll-over event of a vehicle, having an electronic controllable steering system and an electronic control unit, the method comprising the steps of:

the electronic control unit identifies the occurrence of the roll-over risk; and

the electronic control unit generates a signal for the electronic controllable steering system in order to steer the road wheels more into the direction in which the vehicle is tending to roll-over.

2. A method as claimed in claim 1 wherein, the control is split in a passive and an active control algorithm.

3. A method as claimed in claim 1 further comprising the electronic controllable steering system having a steering wheel velocity and torque assistance, wherein, the torque assist from the electronic controllable steering system is at least reduced to force the driver to keep the steering wheel velocity below a certain value.

4. A method as claimed in claim 1, wherein the control is executed by means of a continuously changing damping coefficient defining a delta steering torque.

5. A method as claimed in claim 4, further comprising a steering wheel angle and a steering wheel angle, wherein the steering velocity is limited, whereby the control offsets the steering wheel angle by the driver in case it exceeds a defined velocity at road wheels or steering wheels.

6. A method of claim 5, wherein the control determines an actual steering wheel velocity and the corresponding road wheel velocity generating the reduction of variable gear ratio or generating an delta road wheel angle or delta steering wheel angle.

7. A method of claim 1, wherein the control evaluates a desired steering angle by means of input variables of vehicle state.

8. A method of claim 1, wherein the control evaluates a delta assist torque which at least guides the driver to apply the correct steering angle.

9. A method of claim 1, wherein the control generates an additional difference steering angle to the driver'"'"'s steering angle in order to generate actively a corrective steering action.