ACTIVE SUSPENSION AND ADAPTIVE DAMPING CONFIGURATION

• US 20100253018A1
• Filed: 04/03/2009
• Published: 10/07/2010
• Est. Priority Date: 04/03/2009
• Status: Active Grant

• Current Assignee: ArvinMeritor Technology LLC (Meritor, Inc. (Nevada))
• Original Assignee: ArvinMeritor Technology LLC (Meritor, Inc. (Nevada))
• Inventors: Peterson, John Ashley
• Granted Patent: US 8,172,237 B2
• Time in Patent Office: Days
• US Class Current: 280/5.504
• CPC Class Codes: B60G 17/0155 pneumatic unit
• CPC Class Codes: B60G 17/0485 the springs being pneumatic springs with a flexible wall, e.g. with levelling valves
• CPC Class Codes: B60G 17/0521 the spring having a flexible wall
• CPC Class Codes: B60G 17/08 Characteristics of fluid dampers adjusting fluid dampers in general F16F9/44 - F16F9/53
• CPC Class Codes: B60G 2202/15 Fluid spring
• CPC Class Codes: B60G 2202/152 Pneumatic spring
• CPC Class Codes: B60G 2202/24 Fluid damper
• CPC Class Codes: B60G 2202/314 The spring being a pneumatic spring
• CPC Class Codes: B60G 2202/412 Pneumatic actuator
• CPC Class Codes: B60G 2400/51 in suspension unit
• CPC Class Codes: B60G 2400/51222 Pneumatic
• CPC Class Codes: B60G 2500/22 Spring constant
• CPC Class Codes: B60G 2600/17 Proportional control, i.e. gain control
• CPC Class Codes: B60G 2600/182 Active control means
• CPC Class Codes: B60G 2600/1877 Adaptive Control
• CPC Class Codes: B60G 2600/70 Computer memory; Data storage, e.g. maps for adaptive control
• CPC Class Codes: B60G 2800/91 Suspension Control
• CPC Class Codes: B60G 2800/916 Body Vibration Control

Abstract

A vehicle suspension utilizes an active air suspension system in combination with an adaptive damping system to provide a desired ride and handling output. The active air suspension and adaptive damping system can operate independently of each other, or can work in conjunction with each other to provide the desired output.

Claims

1. A vehicle suspension comprising:

an active air suspension; and

an adaptive damping system that works in conjunction with said active air suspension to provide a desired vehicle ride and handling output.

2. The vehicle suspension according to claim 1 wherein said active air suspension includes at least one air spring assembly including a piston airbag and a primary air bag mounted around said piston airbag, said at least one air spring assembly having a spring characteristic, and wherein said adaptive damping system includes at least one damper associated with said at least one air spring assembly, said at least one damper having a damping characteristic.

3. The vehicle suspension according to claim 2 including a controller that generates electric control signals to actively vary at least one of said damping characteristic and said spring characteristic.

4. The vehicle suspension according to claim 3 wherein said damping characteristic comprises a damper coefficient and wherein said spring characteristic comprises a spring stiffness, and wherein said controller varies said damper coefficient by determining a force required to damp undesirable oscillations generated by variations in said spring stiffness.

5. The vehicle suspension according to claim 4 wherein said controller identifies undesirable oscillations by measuring and monitoring wheel and body oscillations and wherein said controller indirectly determines changing spring stiffnesses based on known pressures within said piston and primary air bags and a look-up table that links spring stiffnesses with pressure levels.

6. The vehicle suspension according to claim 3 wherein said damping characteristic comprises a damper coefficient and wherein said spring characteristic comprises a spring stiffness, and wherein said controller varies said spring stiffness to maintain a desired damper coefficient.

7. The vehicle suspension according to claim 3 wherein said active air suspension and said adaptive damping system operate independently of each other.

8. The vehicle suspension according to claim 7 wherein said controller issues one set of electric control signals to vary said spring characteristic and a separate set of electric control signals to vary said damping characteristic.

9. The vehicle suspension according to claim 3 wherein said controller generates a notification signal that is communicated to said adaptive damping system in response to a change in said spring characteristic, and wherein said adaptive damping system switches to a different predetermined gain schedule in response to said notification signal.

10. The vehicle suspension according to claim 3 wherein said at least one damper comprises an electrically controlled shock absorber.

11. The vehicle suspension according to claim 3 wherein said at least one damper is generally concentric with said at least one air spring assembly.

12. A method of controlling a vehicle suspension comprising the steps of:

(a) providing an active air suspension including at least one air spring assembly comprising a piston airbag and a primary air bag mounted around the piston airbag, the at least one air spring assembly having a spring characteristic;

(b) associating an adaptive damping system with the active air suspension, the adaptive damping system including at least one damper associated with the at least one air spring assembly and having a damping characteristic; and

(c) generating electric control signals to actively vary at least one of the damping characteristic and spring characteristic to provide a desired vehicle ride and handling output.

13. The method according to claim 12 wherein the damping characteristic comprises a damper coefficient and wherein the spring characteristic comprises a spring stiffness, and including varying the damper coefficient by determining a force required to damp undesirable oscillations generated by variations in the spring stiffness.

14. The method according to claim 12 including identifying undesirable oscillations by measuring and monitoring wheel and body oscillations and indirectly determining changing spring stiffnesses based on known pressures within the piston and primary air bags and a look-up table that links spring stiffnesses with pressure levels.

15. The method according to claim 12 wherein the damping characteristic comprises a damper coefficient and wherein the spring characteristic comprises a spring stiffness, and including varying the spring stiffness to maintain a desired damper coefficient.

16. The method according to claim 12 including operating the active air suspension and the adaptive damping system independently of each other.

17. The method according to claim 12 including generating a notification signal that is communicated to the adaptive damping system in response to a change in the spring characteristic, and including switching the adaptive damping system to a different predetermined gain schedule in response to the notification signal.