Variable camber suspension system

• US 20010035617A1
• Filed: 05/15/2001
• Published: 11/01/2001
• Est. Priority Date: 11/21/1996
• Status: Active Grant

• Current Assignee: Khalid M. Choudhery
• Original Assignee: Khalid M. Choudhery
• Inventors: Choudhery, Khalid M.
• Granted Patent: US 6,874,793 B2
• Time in Patent Office: Days
• US Class Current: 280/5.521
• CPC Class Codes: B60G 2200/464 Caster angle
• CPC Class Codes: B60G 3/26 Means for maintaining substantially-constant wheel camber during suspension movement ; Means for controlling the variation of the wheel position during suspension movement B60G3/202, B60G3/22, B60G7/003, B60G7/006 take precedence; means for adjusting camber, castor, or toe-in B62D17/00
• CPC Class Codes: B60G 7/006 Attaching arms to sprung or unsprung part of vehicle, characterised by comprising attachment means controlled by an external actuator, e.g. a fluid or electrical motor B62D7/146 takes precedence
• CPC Class Codes: B62D 17/00 Means on vehicles for adjusting camber, castor, or toe-in
• CPC Class Codes: B62D 9/02 combined with means for inwardly inclining vehicle body on bends

Abstract

A dynamically acting variable camber suspension system (50) having a sensor (56), a controller (58), and camber adjusters (60) associated with each wheel (54) which is employing the VCSS (50) in a vehicle (52). The VCSS (50) detects lateral force acting upon the vehicle (52) when it is turning with the sensor (56), calculates the appropriate dynamic response with the controller (58), and uses the camber adjusters (60) to set negative camber for outside wheels (54) and positive camber for inside wheels (54) in a manner such that road contact points (70) of the wheels (54) are spaced to balance normal forces and footprints (74, 76) of the wheels (54) are equalized to maximize frictional forces.

Claims

1. A suspension system for vehicles having at least one set of transversely opposed wheels, comprising:

sensor means for detecting lateral force acting upon the vehicle;

adjustment means for adjusting camber of each of the wheels; and

control means for receiving output from said sensor means, for suitably calculating from said output sets of appropriately negative cambers for outside instances of the wheels and positive cambers for inside instances of the wheels when the vehicle is turning, and for operating said adjustment means to dynamically adjust the wheels accordingly.

2. The suspension system of

claim 1

, wherein:

said sensor means includes a pendulum which is transversely but not longitudinally movable, to thereby detect the amount of lateral force acting upon the vehicle from the angle of suspension of said pendulum.

3. The suspension system of

claim 1

, wherein:

said sensor means is located proximate to the transverse center of gravity of the vehicle, to thereby accurately detect the amount of lateral force acting upon the vehicle as a whole.

4. The suspension system of

claim 1

, wherein:

said sensor means is a plurality of sensors located about the vehicle to sense a plurality of lateral forces acting upon the vehicle; and

said control means calculates respective cambers for each of the wheels based upon output from said plurality of sensors.

5. The suspension system of

claim 4

, wherein:

said plurality of sensors includes a sensor located proximate to the transverse center of gravity of the vehicle and sensors located at all of the wheels of the vehicle, to thereby accurately detect various lateral forces acting upon the vehicle.

6. The suspension system of

claim 1

, wherein:

said control means further collects statistical data regarding use of the suspension system, thereby permitting analysis of vehicle performance and driver habits.

7. The suspension system of

claim 6

, wherein:

said control means is constructed robustly and said statistical data is stored in a non-volatile manner so that it may be recovered and analyzed after the vehicle is crashed.

8. The suspension system of

claim 1

, further comprising:

alarm means;

wherein

said control means further operates said alarm means to warn occupants of the vehicle as turns approaching unsafe limits are attempted.

9. The suspension system of

claim 8

, wherein:

said alarm means includes at least one member of the set consisting of audible and visual enunciators.

10. The suspension system of

claim 1

, wherein:

every wheel of the vehicle has an associated said adjustment means, regardless of whether transversely opposed.

11. The suspension system of

claim 1

, wherein:

said adjustment means changes camber by pivoting the wheel about an upper located axis of rotation by displacing the wheel laterally at a lower point.

12. The suspension system of

claim 1

, further wherein:

said adjustment means includes an actuator which is a member of the set consisting of pneumatic cylinders, hydraulic cylinders, electric solenoids, electric linear armature actuators, and rotary motor driven actuators.

13. The suspension system of

claim 1

, wherein:

the wheels include tires having rounded outer profiles to permit greater range of camber adjustment by the suspension system while still maintaining roughly equivalent wheel footprints among the wheels in the transversely opposed sets, thereby permitting greater speed of the vehicle in turns.

14. A method for controlling a suspension system of a vehicle having at least one set of transversely opposed wheels when the vehicle is turning, the method comprising:

sensing lateral force acting upon the vehicle;

calculating negative cambers for outside instances of the wheels and positive cambers for inside instances of the wheels based upon said lateral force; and

operating adjustment means to dynamically adjust the wheels accordingly.

15. The method of

claim 14

, wherein:

said lateral force is sensed proximate to the transverse center of gravity of the vehicle, to thereby accurately detect the amount of lateral force acting upon the vehicle as a whole.

16. The method of

claim 14

, further comprising:

said step of sensing lateral force includes sensing at a plurality of locations about the vehicle a plurality of lateral forces acting upon the vehicle; and

said step of calculating includes calculation of respective cambers for each of the wheels based upon output from said plurality of lateral forces which are sensed.

17. The method of

claim 16

, further comprising/wherein:

said plurality of locations include a location proximate to the transverse center of gravity of the vehicle and locations at all of the wheels of the vehicle, to thereby accurately detect the various lateral forces in said plurality of lateral forces acting upon the vehicle.

18. The method of

claim 14

, further comprising:

collecting statistical data regarding use of the suspension system, thereby permitting analysis of vehicle performance and driver habits.

19. The method of

claim 18

, further comprising:

storing said statistical data in a non-volatile manner in a constructed robustly vessel, thereby permitting recovery and analysis after the vehicle is crashed.

20. The method of

claim 14

, further comprising:

analyzing said lateral force in view of limits of operation of the vehicle; and

warning occupants of the vehicle as turns approaching unsafe instances of said limits are approached.

21. The method of

claim 14

, wherein:

said step of calculating further calculates appropriate camber for every wheel of the vehicle; and

further comprising operating individual adjustment means at said every wheel, regardless of whether transversely opposed.

22. The method of

claim 14

, wherein:

said step of operating adjustment means includes pivoting the wheel about an upper located axis of rotation by displacing the wheel laterally at a lower point.

23. The method of

claim 14

, further comprising:

maintaining roughly equivalent wheel footprints among the wheels in the transversely opposed sets by using wheels having tires with rounded outer profiles, thereby permitting greater range of camber adjustment by the suspension system and thus greater speed of the vehicle in turns.