Method for operating a vehicle

• US 8,396,627 B2
• Filed: 05/29/2007
• Issued: 03/12/2013
• Est. Priority Date: 09/26/2006
• Status: Expired due to Fees

• Current Assignee: Continental Automotive GmbH (Continental AG)
• Original Assignee: Continental Automotive GmbH (Continental AG)
• Inventors: Jung, Andreas, Marstaller, Rainer, Mayer, Andreas
• Primary Examiner(s): Zanelli, Michael J.
• Application Number:
  US12/442,630
• Publication Number:
  US 20100036561A1
• Time in Patent Office: 2,114 Days
• Field of Search: None
• US Class Current: 701/37
• CPC Class Codes: B60G 17/0195 characterised by the regulation being combined with other vehicle control systems conjoint control of vehicle sub-units including control of suspension systems B60W10/22
• CPC Class Codes: B60G 2400/106 longitudinal with regard to vehicle, e.g. braking
• CPC Class Codes: B60G 2400/52 in tyre
• CPC Class Codes: B60G 2400/61 Load distribution
• CPC Class Codes: B60G 2400/63 Location of the center of gravity
• CPC Class Codes: B60G 2400/64 Wheel forces, e.g. on hub, spindle or bearing
• CPC Class Codes: B60G 2500/30 Height or ground clearance
• CPC Class Codes: B60G 2600/17 Proportional control, i.e. gain control
• 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 2800/22 Braking, stopping
• CPC Class Codes: B60G 2800/70 Estimating or calculating vehicle parameters or state variables
• CPC Class Codes: B60W 40/10 related to vehicle motion
• CPC Class Codes: B60W 40/13 Load or weight

Abstract

In a method for operating a vehicle with wheel suspensions which each have a characteristic curve, the characteristic curve generates a relation between the weight of the vehicle, applied to each wheel suspension, and the respective height of the vehicle at the wheel suspension point. At least two height sensors detect the height at the wheel suspensions, a reference height is associated with the height sensors and represents a pre-defined loading state of the vehicle. The method provides: detecting the height, determining the forces applied to the vehicle, determining the acceleration of the vehicle on the basis of the forces applied to the vehicle, determining an estimated value for the mass of the vehicle from the forces and the acceleration of the vehicle, and determining values representing the reference heights from at least the estimated value for the mass of the vehicle, the characteristic curves of the wheel suspensions, and the detected heights.

Claims

1. A method for operating a vehicle which comprises wheel suspensions and characteristic curves respectively associated therewith, each characteristic curves respectively generating a relation between the weight of the vehicle proportionally applied to a respective wheel suspension and a respective height of the vehicle at a wheel suspension point, and at least two height sensors for detecting heights at the wheel suspensions, the method comprising the steps of:

detecting the heights,

determining forces applied to the vehicle,

determining an acceleration of the vehicle due to the forces applied to the vehicle,

determining an estimated value of the mass of the vehicle from the determined forces applied to the vehicle and the determined acceleration of the vehicle, and

determining values which represent one or more reference heights from at least one determined estimated value of the mass of the vehicle, the characteristic curves of the wheel suspensions, and the detected heights, the one or more reference heights representing a pre-defined loading state of the vehicle.

2. The method according to claim 1, comprising the steps of:

detecting further heights, and

determining the mass of the vehicle, according to at least the values which represent the reference heights, the characteristic curves of the wheel suspensions and the further heights.

3. The method according to claim 1, comprising the step of averaging the values which represent the reference heights.

4. The method according to claim 1, wherein at least the drive force, the braking force, the drag or the rolling resistance of the vehicle are taken into account for determining the force applied to the vehicle.

5. The method according to claim 1, wherein longitudinal acceleration is detected as acceleration of the vehicle by means of a longitudinal acceleration sensor.

6. The method according to claim 1, wherein via at least one wheel velocity sensor a wheel velocity is detected, and the acceleration of the vehicle is determined from the time derivative of the detected wheel velocity.

7. The method according to claim 1, wherein the estimated value of the mass in pre-defined vehicle situations is detected.

8. The method according to claim 1, wherein an average estimated value of the mass is determined according to the estimated values of the mass.

9. The method according to claim 1, wherein (a) the determination of the estimated value of the mass of the vehicle from the forces applied to the vehicle and the acceleration of the vehicle, (b) the determination of the values which represent the reference heights and (c) the determination of the mass of the vehicle are carried out in a quasi parallel manner from the values which represent the reference heights, the detected heights, and the characteristic curves of the wheel suspensions.

10. The method according to claim 9, wherein as soon as the values which represent the reference heights have been determined, said values are used for determining the mass of the vehicle.

11. The method according to claim 9, wherein the values which represent the reference heights are only determined when the estimated value of the mass of the vehicle is in a pre-defined value range.

12. The method according to claim 9, wherein the values which represent the reference heights are only used for determining the mass of the vehicle after these values have been altered by a pre-defined value.

13. The method according to claim 1, wherein for determining the values which represent the reference heights, at least one Kalman filter is used in which already determined values together with values just detected are linked for determining new values.

14. The method according to claim 1, wherein the characteristic curves of the wheel suspensions are determined according to the differences in height and differences in mass of the vehicle.

15. The method according to claim 1, wherein braking systems or tire air pressures are set according to the determined mass of the vehicle.

16. A device for operating a vehicle comprising wheel suspensions and characteristic curves respectively associated therewith, each characteristic curves respectively generating a relation between the weight of the vehicle proportionally applied to a respective wheel suspension and a respective height of the vehicle at a wheel suspension point, and at least two height sensors for detecting heights at the wheel suspensions, the device being configured:

to detect the heights,

to determine forces applied to the vehicle,

to determine an acceleration of the vehicle due to the forces applied to the vehicle,

to determine an estimated value of the mass of the vehicle from the determined forces applied to the vehicle and the determined acceleration of the vehicle, and

to determine values which represent one or more reference heights from at least one determined estimated value of the mass of the vehicle, the characteristic curves of the wheel suspensions, and the detected heights, the one or more reference heights representing a pre-defined loading state of the vehicle.

17. The device according to claim 16, wherein the device is further configured to detect further heights, and determine the mass of the vehicle, according to at least the values which represent the reference heights, the characteristic curves of the wheel suspensions and the further heights.

18. The device according to claim 16, wherein the device is further configured to average the values which represent the reference heights.

19. The device according to claim 16, wherein the device is further configured to take into account at least the drive force, the braking force, the drag or the rolling resistance of the vehicle for determining the force applied to the vehicle.

20. The device according to claim 16, comprising a longitudinal acceleration sensor configured to detect longitudinal acceleration as acceleration of the vehicle.