Active suspension system for a vehicle and method of operating the same

• US 8,185,269 B2
• Filed: 12/16/2008
• Issued: 05/22/2012
• Est. Priority Date: 12/16/2008
• Status: Expired due to Fees

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Li, Yunjun, Herrick, Timothy J., McMahon, Nancy, Opiteck, Steven A., Cui, John X., Majersik, Loren J., Wilmot, Nathan A.
• Primary Examiner(s): Ilan, Ruth
• Application Number:
  US12/335,946
• Publication Number:
  US 20100152969A1
• Time in Patent Office: 1,253 Days
• Field of Search: 701/37, 280/5.514, 280/5.517, 280/6.15, 280/6.157, 280/5.501
• 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 2400/80 Exterior conditions
• CPC Class Codes: B60G 2400/90 Other conditions or factors
• CPC Class Codes: B60G 2401/16 GPS track data
• CPC Class Codes: B60G 2401/21 Laser
• CPC Class Codes: B60G 2500/30 Height or ground clearance
• CPC Class Codes: G08G 1/096725 where the received information generates an automatic action on the vehicle control

Abstract

An active suspension system and method for controlling the height of a vehicle. In an exemplary embodiment, the active suspension system receives information from one or more input sources, including both internal and external vehicle inputs, and uses that information to actively control the vehicle height. By doing so, the active suspension system can reduce aerodynamic drag on the vehicle and improve the vehicle'"'"'s fuel economy, ride comfort, handling, and other aspects of operation. Some examples of external vehicle inputs that may be used include: short-range road and vehicle information, as well as long-range traffic, road and route information.

Claims

1. A method of controlling an active suspension system for a vehicle, comprising the steps of:

(a) receiving one or more external vehicle input(s);

(b) using the external vehicle input(s) to determine if cautionary conditions exist that make adjusting the active suspension system less than ideal and to determine a desired vehicle height that improves the fuel efficiency, ride comfort or ride handling of the vehicle; and

(c) adjusting the active suspension system from a current vehicle height to the desired vehicle height so that the fuel efficiency, ride comfort or ride handling of the vehicle is improved when there are no cautionary conditions.

2. The method of claim 1, wherein the external vehicle input(s) include at least one input selected from the group of short-range external vehicle inputs consisting of:

short-range road information, short-range vehicle information, and short-range traffic information.

3. The method of claim 1, wherein the external vehicle input(s) include at least one input selected from the group of long-range external vehicle inputs consisting of:

long-range traffic information, long-range road information, and long-range route information.

4. The method of claim 1, wherein step (a) further comprises receiving external vehicle input in the form of short-range road information that pertains to an upcoming road surface and is provided by a vehicle-mounted vision system.

5. The method of claim 1, wherein step (a) further comprises receiving external vehicle input in the form of short-range vehicle information that pertains to a nearby vehicle and is provided by a vehicle-mounted radar, laser, ladar, or ultrasonic sensor.

6. The method of claim 1, wherein step (a) further comprises receiving external vehicle input in the form of short-range traffic information that is provided by a traffic information broadcasting system and pertains to an upcoming stop sign, traffic light, or intersection.

7. The method of claim 1, wherein step (a) further comprises receiving external vehicle input in the form of long-range road information that is provided by a GPS-based navigation system and pertains to an upcoming exit ramp, stretch of road, or speed limit change.

8. The method of claim 1, wherein step (a) further comprises receiving external vehicle input in the form of long-range route information that is provided by a GPS-based navigation system and pertains to a destination or other aspect of a calculated navigational route.

9. The method of claim 1, further comprising the steps of:

evaluating one or more external vehicle input(s) that pertain to objects, conditions, surroundings or environments located outside of the vehicle in order to determine if cautionary conditions exist that make adjusting the active suspension system less than ideal; and

if such cautionary conditions exist then temporarily suspending the active suspension system.

10. The method of claim 1, wherein step (b) further comprises using the external vehicle input(s) to select from a lowered vehicle height for improved fuel efficiency, ride comfort or ride handling, a default vehicle height for typical driving conditions, or a raised vehicle height for certain off-road conditions.

11. The method of claim 1, wherein step (c) further comprises adjusting the active suspension system from the current vehicle height to the desired vehicle height by changing a level setting that reduces the aerodynamic drag on the vehicle so that the front of the vehicle is lower than the rear of the vehicle.

12. A method of controlling an active suspension system for a vehicle, comprising the steps of:

(a) receiving one or more external vehicle input(s) checking the state of a vehicle cruise control;

(b) using the external vehicle input(s) and the state of the vehicle cruise control to determine a desired vehicle height, if the vehicle cruise control is active then selecting a lowered vehicle height; and

(c) adjusting the active suspension system to the desired vehicle height, wherein steps (a) and (b) are performed before step (c).

13. An active suspension system for a vehicle, comprising:

a suspension control module electronically coupled to one or more internal vehicle input(s), one or more external vehicle input(s), and a vehicle cruise control;

an actuator controlled by the suspension control module; and

a sprung mass mechanically coupled to the actuator, wherein the suspension control module uses information from the internal and external vehicle input(s) to drive the actuator and control a vehicle height, and if the vehicle cruise control is active then the suspension control module sets the vehicle height to a lowered vehicle height.

14. An active suspension system for a vehicle, comprising:

a suspension control module electronically coupled to one or more internal vehicle input(s) and one or more external vehicle input(s);

an actuator controlled by the suspension control module; and

a sprung mass mechanically coupled to the actuator, wherein the suspension control module uses information from the internal and external vehicle input(s) to determine if cautionary conditions exist that make adjusting the active suspension system less than ideal and, when there are no cautionary conditions, to drive the actuator and change a vehicle height between a lowered vehicle height for improved fuel efficiency, ride comfort or ride handling, a default vehicle height for typical driving conditions, or a raised vehicle height for certain off-road conditions.

15. The active suspension system of claim 14, wherein the external vehicle input(s) include at least one input selected from the group of short-range external vehicle inputs consisting of:

short-range road information, short-range vehicle information, and short-range traffic information.

16. The active suspension system of claim 14, wherein the external vehicle input(s) include at least one input selected from the group of long-range external vehicle inputs consisting of:

long-range traffic information, long-range road information, and long-range route information.

17. The active suspension system of claim 14, wherein the suspension control module is coupled to a vehicle-mounted vision system and receives external vehicle input in the form of short-range road information pertaining to an upcoming road surface.

18. The active suspension system of claim 14, wherein the suspension control module is coupled to a vehicle-mounted radar, laser, ladar, or ultrasonic sensor and receives external vehicle input in the form of short-range vehicle information pertaining to a nearby vehicle.

19. The active suspension system of claim 14, wherein the suspension control module is coupled to a vehicle-mounted receiver and receives external vehicle input in the form of short-range traffic information that is provided by a traffic information broadcasting system and pertains to an upcoming stop sign, traffic light, or intersection.

20. The active suspension system of claim 14, wherein the suspension control module is coupled to a GPS-based navigation system and receives external vehicle input in the form of long-range road information that pertains to an upcoming exit ramp, stretch of road, or speed limit change.

21. The active suspension system of claim 14, wherein the suspension control module is coupled to a GPS-based navigation system and receives external vehicle input in the form of long-range route information that pertains to a destination or other aspect of a calculated navigational route.

22. The active suspension system of claim 14, wherein the system is a pneumatic suspension system and the actuator includes an air spring.