Method for navigating a terrestrial vehicle

• US 6,349,260 B1
• Filed: 09/06/2000
• Issued: 02/19/2002
• Est. Priority Date: 09/21/1999
• Status: Expired due to Fees

• Current Assignee: Mannesmann VDO AG (Continental AG)
• Original Assignee: Mannesmann VDO AG (Continental AG)
• Inventors: de Jong, Cornelis Dick
• Primary Examiner(s): Beaulieu, Yonel
• Application Number:
  US09/655,953
• Time in Patent Office: 531 Days
• Field of Search: 701/200, 701/207, 701/213, 701/214, 701/216, 701/24, 701/23, 342/357.01, 342/357.05, 342/357.08
• US Class Current: 701/207
• CPC Class Codes: G01C 22/02 by conversion into electric waveforms and subsequent integration, e.g. using tachometer generator G01C22/002, G01C22/004, G01C22/006 take precedence
• CPC Class Codes: G01C 25/00 Manufacturing, calibrating, cleaning, or repairing instruments or devices referred to in the other groups of this subclass testing, calibrating or compensating compasses G01C17/38
• CPC Class Codes: G01S 19/52 Determining velocity

Abstract

A method for calibration of a path length variable being used for navigating a terrestrial vehicle. The path length variable is measured by determining the number of revolutions of a wheel. For calibration of this value, two speed values are ascertained. A first speed value is determined using the number of revolutions of the wheel and a second speed value is determined using at least one external position sensor. One of the speed values is classified in a plurality of classes, and a calibration value in a class is ascertained using the speed values from this class.

Claims

1. A method for calibration of a path length variable for use in navigating a terrestrial vehicle wherein the path length variable is measured by determining the number of revolutions of a wheel, comprising the steps of ascertaining a first speed value using the number of revolutions of the wheel, ascertaining a second speed value using at least one external position sensor, classifying one of the two speed values in one of a plurality of classes, each class of which comprises a predetermined speed range, and ascertaining a calibration value in a class by using the speed values from the class.

2. The method as claimed in claim 1, wherein ascertaining the second speed value further comprises using the Doppler effect.

3. The method as claimed in claim 1, wherein calibration is ongoing, at least in sections.

4. The method as claimed in claim 3, further comprising, at predetermined speeds, using a calibration value from a predetermined higher speed class to ascertain a distance, if this calibration value is present.

5. The method as claimed in claim 1, further comprising ascertaining each calibration value using a multiplicity of calibration operations.

6. The method as claimed in claim 5, further comprising determining the calibration value by filtering the results of the individual calibration operations.

7. The method as claimed in claim 4, further comprising ascertaining each calibration value using a multiplicity of calibration operations.

8. The method as claimed in claim 7, further comprising determining the calibration value by filtering the results of the individual calibration operations.

9. The method as claimed in claim 1, wherein calibration is not carried out if an acceleration value determined by using the external position sensor exceeds a predetermined acceleration value.

10. The method as claimed in claim 9, wherein the predetermined acceleration value is 1 m/s².

11. The method as claimed in claim 1, wherein calibration is not carried out if the speed ascertained by using the external position sensor is less than 5 m/s.

12. The method as claimed in claim 8, wherein calibration is not carried out if the speed ascertained by using the external position sensor is less than 5 m/s.

13. The method as claimed in claim 1, wherein the path length variable ascertained is a distance per pulse, the pulses being integrated until a new signal is available from the external position sensor.

14. The method as claimed in claim 8, wherein the path length variable ascertained is a distance per pulse, the pulses being integrated until a new signal is available from the external position sensor.