Method and device for determining the geometric vehicle inclination of a motor vehicle

• US 7,194,341 B2
• Filed: 10/18/2002
• Issued: 03/20/2007
• Est. Priority Date: 11/06/2001
• Status: Active Grant

• Current Assignee: Volkswagen AG
• Original Assignee: Volkswagen AG
• Inventors: Altenkirch, Manfred
• Primary Examiner(s): Zanelli; Michael J.
• Application Number:
  US10/494,533
• Publication Number:
  US 20050085950A1
• Time in Patent Office: 1,614 Days
• Field of Search: None
• US Class Current: 701/1
• CPC Class Codes: B60G 17/01908 Acceleration or inclination sensors characterised by the use of gyroscopes B60G21/08
• 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 2400/0512 Pitch angle
• CPC Class Codes: B60G 2400/106 longitudinal with regard to vehicle, e.g. braking
• CPC Class Codes: B60G 2400/204 Vehicle speed
• CPC Class Codes: B60G 2400/60 Load
• CPC Class Codes: B60G 2600/14 Differentiating means, i.e. differential control
• CPC Class Codes: B60G 2800/014 Pitch; Nose dive
• CPC Class Codes: B60G 2800/0192 longitudinal with regard to vehicle
• CPC Class Codes: B60G 2800/18 Starting, accelerating
• CPC Class Codes: B60G 2800/702 Improving accuracy of a sensor signal
• CPC Class Codes: B60R 2021/01306 monitoring vehicle inclination
• CPC Class Codes: B60R 21/0132 responsive to vehicle motion parameters , e.g. to vehicle longitudinal or transversal deceleration or speed value
• CPC Class Codes: B60T 8/172 Determining control parameters used in the regulation, e.g. by calculations involving measured or detected parameters B60T8/17551 takes precedence
• CPC Class Codes: B60T 8/17551 determining control parameters related to vehicle stability used in the regulation, e.g. by calculations involving measured or detected parameters
• CPC Class Codes: B60T 8/1769 specially adapted for vehicles having more than one driven axle, e.g. four-wheel drive vehicles
• CPC Class Codes: B60W 2520/105 Longitudinal acceleration
• CPC Class Codes: B60W 2520/125 Lateral acceleration
• CPC Class Codes: B60W 2520/16 Pitch
• CPC Class Codes: B60W 2520/18 Roll
• CPC Class Codes: B60W 2552/15 : Road slope, i.e. the inclination of a road segment in the longitudinal direction
• CPC Class Codes: B60W 30/04 : related to roll-over prevention
• CPC Class Codes: G01C 9/06 : Electric or photoelectric indication or reading means

Abstract

A method is for determining a geometric vehicle inclination α of a motor vehicle, where an acceleration signal of at least one acceleration sensor is used and a speed gradient dv/dt is determined from a measured vehicle speed v, where a) in the case of a moving or standing vehicle, an acceleration value a_S is derived from a force acting on the acceleration sensor, b) a corrected acceleration value a_korr is determined as a function of the speed gradient dv/dt, and c) the current vehicle inclination α is directly deduced from the corrected acceleration value a_korr. In addition, a device for implementing a method to determine a geometric vehicle inclination α of a motor vehicle, the device includes a speed-measuring device and at least one acceleration sensor, a programmable and readable microcontroller being provided, with the aid of which the current vehicle inclination a may be calculated from the values of the speed-measuring device and the acceleration sensor at a vehicle speed v of the vehicle greater than or equal to zero, and directly transmitted to at least one control unit.

Claims

1. A method for determining a geometric vehicle inclination of a motor vehicle, comprising:

calculating a speed gradient from a measured vehicle speed;

deriving an acceleration value from a force acting on an acceleration sensor for one of (a) a traveling vehicle and (b) a standing vehicle, the acceleration sensor configured to generate an acceleration signal;

calculating a corrected acceleration value as a function of the speed gradient;

directly calculating a current vehicle inclination from the corrected acceleration value;

comparing the corrected acceleration value to a predetermined threshold acceleration value of the acceleration sensor; and

determining one of (a) an incline and (b) a decline as a function of a deviation direction.

2. The method according to claim 1, wherein the vehicle inclination is calculated in the vehicle inclination calculating step according to the equation:

3. The method according to claim 1, wherein the corrected acceleration value satisfies the relationship a_korr=a_s−

dv/dt;

wherein a_korr represents the corrected acceleration value, a_s represents the acceleration value, and dv/dt represents the speed gradient.

4. The method according to claim 1, further comprising determining a longitudinal inclination of the vehicle from an acceleration signal of a longitudinal-acceleration sensor.

5. The method according to claim 1, further comprising determining a transverse acceleration of the vehicle from an acceleration signal of a transverse-acceleration sensor and a centrifugal acceleration.

6. A device for determining a geometric vehicle inclination of a motor vehicle, comprising:

a speed-measurement device;

at least one acceleration sensor; and

a programmable and readable microcontroller configured to calculate a current vehicle inclination based on a corrected acceleration value determined from values of the speed-measurement device and the acceleration sensor at a vehicle speed of the vehicle greater than or equal to zero and configured to directly transmit the vehicle inclination to at least one control unit;

wherein the microcontroller is configured to compare the corrected acceleration value to a predetermined threshold acceleration value of the acceleration sensor and determine one of (a) an incline and (b) a decline as a function of a deviation direction.

7. The device according to claim 6, wherein the at least one control unit includes a transmission control unit configured to process signals output by the microcontroller.

8. The device according to claim 6, wherein the at least one control unit includes at least one of an engine control unit, an all-wheel-drive control unit, a brake control unit, an adaptive cruise-control unit, a vehicle-dynamics control unit and a drive-train control unit, the at least one of the engine control unit, the all-wheel-drive control unit, the brake control unit, the adaptive cruise-control unit, the vehicle-dynamics control unit and the drive-train control unit configured to process signals output by the microcontroller.

9. The device according to claim 6, further comprising an instrument display configured to display the vehicle inclination.

10. The device according to claim 6, further comprising an arrangement configured to activate a rollover warning device in response to a specifiable transverse inclination in accordance with the vehicle inclination determined by the microcontroller.

11. A device for determining a geometric vehicle inclination of a motor vehicle, comprising:

means for calculating a speed gradient from a measured vehicle speed;

means for deriving an acceleration value from a force acting on an acceleration sensor for one of (a) a traveling vehicle and (b) a standing vehicle, the acceleration sensor configured to generate an acceleration signal;

means for calculating a corrected acceleration value as a function of the speed gradient;

means for directly calculating a current vehicle inclination from the corrected acceleration value;

means for comparing the corrected acceleration value to a predetermined threshold acceleration value of the acceleration sensor; and

means for determining one of (a) an incline and (b) a decline as a function of a deviation direction.