Ride Performance Optimization In An Active Suspension System

• US 20130345933A1
• Filed: 06/25/2012
• Published: 12/26/2013
• Est. Priority Date: 06/25/2012
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Salib, Albert Chenouda, Russell, David Michael, Hoffmann, Uwe, Suermann, Marc, Norton, Russ Lee, Bulat, Benjamin, Suter, Greg Gregory
• Granted Patent: US 8,918,253 B2
• Time in Patent Office: Days
• US Class Current: 701/37
• CPC Class Codes: B60G 17/0165 to an external condition, e.g. rough road surface, side wind
• CPC Class Codes: B60G 17/018 characterised by the use of a specific signal treatment or control method
• CPC Class Codes: B60G 17/06 Characteristics of dampers , e.g. mechanical dampersB60G17/015 takes precedence
• CPC Class Codes: B60G 17/08 Characteristics of fluid dampers adjusting fluid dampers in general F16F9/44 - F16F9/53
• CPC Class Codes: B60G 2400/202 Piston speed; Relative velocity between vehicle body and wheel
• CPC Class Codes: B60G 2500/10 Damping action or damper
• CPC Class Codes: B60G 2600/02 Retarders, delaying means, dead zones, threshold values, cut-off frequency, timer interruption

Abstract

An active vehicle suspension system includes an active damping mechanism operatively coupled to a vehicle wheel and configured for controlling a damping force applied to the wheel responsive to a control signal. A controller is operatively coupled to the damping mechanism and configured for generating a control signal to the damping mechanism responsive to velocity of the wheel in a downward vertical direction.

Claims

1. An active vehicle suspension system comprising:

an active damping mechanism operatively coupled to a vehicle wheel and configured for controlling a damping force applied to the wheel responsive to a control signal; and

a controller operatively coupled to the damping mechanism and configured for generating a control signal to the damping mechanism responsive to a comparison of a velocity of the wheel in a downward vertical direction to a threshold velocity.

2. The system of claim 1

wherein the controller is configured to generate a control signal to increase a damping force applied to the wheel responsive to the velocity of the wheel exceeding the threshold velocity.

3. The system of claim 1 wherein the controller is configured to recalculate the velocity of the wheel responsive to the velocity of the wheel not exceeding the threshold velocity.

4. The system of claim 1 further comprising a timer element operatively coupled to the controller and configured to measure a time elapsed following an activation of the timer element, and wherein the controller is configured to activate the timer element prior to comparison of the velocity of the wheel to the threshold velocity.

8. The method of claim of 4 wherein the controller is configured to compare an elapsed time measured by the timer to a time threshold prior to comparison of the velocity of the wheel to the threshold velocity.

10. The system of claim 4 wherein the controller is configured to activate the timer element responsive to comparison of the velocity of the wheel to another threshold velocity.

5. A method for operating a vehicle active suspension system including a timer element operatively associated therewith, comprising the steps of:

determining a first instantaneous velocity of a vehicle wheel in a downward direction;

comparing the first instantaneous velocity to a first velocity threshold;

where the first instantaneous velocity is greater than the first velocity threshold, activating the timer element; and

controlling a damping level applied to the wheel, responsive to a comparison of a second instantaneous velocity of the wheel in a downward direction to a second velocity threshold, the comparison being performed prior to a first time threshold occurring after activation of the timer element.

6. The method of claim 5 wherein the step of controlling the damping level comprises the step of, where the velocity of the wheel does not exceed the second threshold velocity, recalculating the instantaneous velocity of the wheel.

7. The method of claim 5 wherein the step of controlling the damping level comprises the step of, where the velocity of the wheel exceeds the second threshold velocity, controlling a damping mechanism operatively coupled to the wheel to increase a damping force applied to the wheel.

9. In a vehicle active suspension system, a method for applying a damping force to a vehicle wheel moving in a downward vertical direction, comprising the steps of:

measuring a time during which the wheel moves in the direction;

measuring a velocity of the wheel in the direction;

comparing the time to a threshold;

where the time exceeds the threshold, decreasing the damping force to a predetermined value;

where the time does not exceed the threshold, comparing the velocity to another threshold; and

adjusting the damping force responsive to the comparison between the velocity and the other threshold.

11. The method of claim 9 wherein the step of controlling the damping force comprises the step of applying a maximum available damping force to the wheel when the velocity exceeds the other threshold.

12. The method of claim 11 further comprising the step of maintaining the maximum available damping force until after the time reaches a predetermined value.

13. The method of claim 11 wherein the step of controlling the damping force comprises the step of incrementally increasing the damping force when the velocity does not exceed the other threshold.