System for multiple navigation components

• US 20050256637A1
• Filed: 05/09/2005
• Published: 11/17/2005
• Est. Priority Date: 05/12/2004
• Status: Active Grant

• Current Assignee: Northrop Grumman Systems Corporation (Northrop Grumman Corporation)
• Original Assignee: Northrop Grumman Systems Corporation (Northrop Grumman Corporation)
• Inventors: Lipma, Maureen, Lipman, Jerome S., Tazartes, Daniel A., Volk, Charles H., Huddle, James R.
• Granted Patent: US 8,224,574 B2
• Time in Patent Office: Days
• US Class Current: 701/207
• CPC Class Codes: G01C 21/166 Mechanical, construction or arrangement details of inertial navigation systems
• CPC Class Codes: G01C 21/188 for accumulated errors, e.g. by coupling inertial systems with absolute positioning systems
• CPC Class Codes: G01C 25/005 initial alignment, calibration or starting-up of inertial devices

Abstract

An exemplary navigation system uses a master navigation component at a first location in a vehicle and a slave navigation component at a second location that is a variable displacement to the first location due to physical deformation of the vehicle. Static and dynamic location components provide static and dynamic information of the displacement between the first and second locations. An error estimator estimates errors in the navigational measurement data generated by the slave navigation component based on the navigational measurement data generated by the master navigation component and the displacement information provided by the static and dynamic location components. The master navigation component corrects the navigation measurement data of the slave navigation component based on the determined error and translates the corrected navigation measurement data of the slave navigation component into navigational measurement data in its coordinate system.

Claims

1. An apparatus, comprising:

a master navigation component that establishes a first coordinate system; and

one or more slave navigation components that determine navigation measurement data of the one or more slave navigation components each in their own secondary coordinate system;

wherein the one or more slave navigation components provide the navigation measurement data of the one or more slave components each in their own secondary coordinate system to the master navigation component;

wherein the master navigation component compares the navigation measurement data of the one or more slave components each in their own secondary coordinate system to navigation measurement data for the master navigation component in the first coordinate system;

wherein the master navigation component translates the navigation measurement data of the one or more slave navigation components in the second coordinate system into navigation measurement data of the one or more slave navigation components in the first coordinate system.

2. The apparatus of claim 1 wherein the master navigation component estimates errors in the navigation measurement data of the one or more slave navigation components.

3. The apparatus of claim 2 wherein the master navigation component estimates errors in the navigation measurement data of the one or more slave navigation components through employment of a Kalman filter.

4. The apparatus of claim 2 wherein the master navigation component corrects the navigation measurement data of the one or more slave navigation components each in their own secondary coordinate system based on the estimated errors.

5. The apparatus of claim 1 wherein the master navigation component is disposed at a first location in a vehicle and a first one of the slave navigation components is disposed at a second location in the vehicle, the first and second coordinate systems being associated with the first and second locations, respectively.

6. The apparatus of claim 5 further comprising a static location component coupled to the master navigation component wherein the static location component provides static information of the distance between the first and second locations, the master navigation component estimates the error in the navigation measurement data of the first slave navigation component at the second location based on the static distance information.

7. The apparatus of claim 6 further comprising a dynamic location component coupled to the master navigation component wherein the dynamic location component provides dynamic information of the displacement between the first and second locations, the displacement between the first slave navigation component and the master navigation component being variable due to physical deflection of the second location relative to the first location, the master navigation component estimating the error in the navigation measurement data of the first slave navigation component at the second location based on the dynamic displacement information.

8. The apparatus of claim 7 wherein the master navigation component corrects the navigation measurement data of the first slave navigation component based on the static distance and dynamic displacement information.

9. The apparatus of claim 8 wherein the master navigation component translates the navigation measurement data of the first slave navigation component in the second coordinate system into navigation measurement data in the first coordinate system based on the navigation measurement data corrected for static and dynamic displacement information.

10. The apparatus of claim 7 further comprising a summation element that receives inputs from the static location component and the dynamic location component, the summation element providing an output to the filter that provides estimates of error in the navigation measurement data of the second coordinate system relative to the first coordinate system.

11. The apparatus of claim 7 wherein the master and slave navigation components each includes a time synchronization component that encodes master and slave navigation measurement data with time information so that master and slave measurement data as of substantially the same time can be utilized in estimating the error in the navigation measurement data of the first slave navigation component at the second location based on the dynamic displacement information.

12. A navigation system comprising:

a master navigation component that generates navigation measurement data and establishes a first coordinate system at a first location in a vehicle;

a slave navigation component that generates navigation measurement data and establishes a second coordinate system in a second location in the vehicle where the displacement between the first and second locations is variable due to physical deformation of the vehicle;

a dynamic location component coupled to the master navigation component where the dynamic location component provides dynamic information of the displacement between the first and second locations;

the master navigation component including an error estimator that estimates errors in the navigation measurement data generated by the slave navigation component based on the navigation measurement data generated by the master navigation component and the dynamic displacement information provided by the dynamic location component;

the master navigation component correcting the navigation measurement data of the slave navigation component based on the error determined by the error estimator;

the master navigation component translating the corrected navigation measurement data of the slave navigation component into navigation measurement data in the first coordinate system.

13. The navigation system of claim 12 further comprising a static location component coupled to the master navigation component where the static location component provides static information of the distance between the first and second locations, the error estimator estimating errors in the navigational measurement data generated by the slave navigation component based on the static distance information provided by the static location component.

14. The navigation system of claim 13 further comprising a summation element that receives inputs from the static and dynamic location components, the summation element providing an output to the error estimator that estimates the errors based on the output provided from the summation element.

15. The navigation system of claim 14 further comprising a closed loop feedback circuit comprising the slave navigation component, the static and dynamic location elements, the summation element and the error estimator that minimizes the estimated error by updating the location of the slave navigational component relative to the location of the master navigation component.

16. The navigation system of claim 12 wherein the master and slave navigation components each includes a time synchronization component that encodes master and slave navigation measurement data with time information so that master and slave measurement data as of substantially the same time can be utilized by the error estimator in estimating the error in the navigation measurement data of the first slave navigation component at the second location based on the dynamic displacement information.

17. The navigation system of claim 12 wherein one or more additional slave navigation components generate navigation measurement at one or more additional locations in the vehicle where the displacement between the first and the additional locations is variable due to physical deformation of the vehicle.

18. The navigation system of claim 17 wherein a dynamic location component a dynamic location component provides dynamic information of the displacement between the first and the one or more additional locations.

19. The navigation system of claim 18 wherein the master navigation component includes an error estimator that estimates errors in the navigation measurement data generated by the one or more additional slave navigation components based on the navigation measurement data generated by the master navigation component and the dynamic displacement information provided by the dynamic location component.

20. The navigation system of claim 19 wherein the master navigation component corrects the navigation measurement data of the one or more additional slave navigation components based on the error determined by the error estimator.

21. The navigation system of claim 20 wherein the master navigation component translates the corrected navigation measurement data of the one or more additional slave navigation components into navigation measurement data in the first coordinate system.

22. A method for determining navigation information comprising the steps of:

generating master navigation measurement data with a first coordinate system at a first location in a vehicle;

generating slave navigation measurement data with a second coordinate system in a second location in the vehicle;

determining dynamic information of the displacement between the first and second locations;

estimating errors in the slave navigation measurement data based on the master navigation measurement data and the dynamic displacement information;

correcting the slave navigation measurement data based on the estimated error;

translating the corrected slave navigation measurement data into navigation measurement data in the first coordinate system.

23. The method of claim 22 further comprising generating static information of the distance between the first and second locations, the estimating error step estimating errors in the slave navigation measurement data based on the static and dynamic distance information.

24. The method of claim 23 further comprising the step of summing the static and dynamic location information, and generating an output based on the summation, the error estimation is based on the said output.

25. The method of claim 24 further comprising using a closed loop feedback system based on the slave navigation information, the static and dynamic location information, the summation output, and the estimated error information to update the location of the second location relative to the first location.

26. The method of claim 22 further comprising the step of encoding master and slave navigation measurement data with time information so that master and slave measurement data as of substantially the same time is used in estimating the error in the navigation measurement data of the first slave navigation component at the second location based on the dynamic displacement information.

27. A method for determining navigation information comprising the steps of:

generating master navigation measurement data with a first coordinate system at a first location in a vehicle;

generating one or more sets of slave navigation measurement data with a one or more additional coordinate systems in one or more additional locations in the vehicle;

determining dynamic information of the displacement between the first and the additional locations;

estimating errors in the slave navigation measurement data based on the master navigation measurement data and the dynamic displacement information;

correcting the slave navigation measurement data based on the estimated error;

translating the corrected slave navigation measurement data into navigation measurement data in the first coordinate system.

28. The method of claim 27 further comprising generating static information of the distance between the first and second locations, the estimating error step estimating errors in the slave navigation measurement data based on the static and dynamic distance information.

29. The method of claim 28 further comprising the step of summing the static and dynamic location information, and generating an output based on the summation, the error estimation is based on said output.

30. The method of claim 29 further comprising using a closed loop feedback system based on the slave navigation information, the static and dynamic location information, the summation output, and the estimated error information to update the location of the second location relative to the first location.

31. The method of claim 29 further comprising the step of encoding master and slave navigation measurement data with time information so that master and slave measurement data as of substantially the same time is used in estimating the error in the navigation measurement data of the first slave navigation component at the second location based on the dynamic displacement information.