Moving platform INS range corrector (MPIRC)

• US 9,423,509 B2
• Filed: 06/27/2011
• Issued: 08/23/2016
• Est. Priority Date: 06/25/2010
• Status: Active Grant

• Current Assignee: Trusted Positioning Inc. (TDK Corporation)
• Original Assignee: Trusted Positioning Inc. (TDK Corporation)
• Inventors: Georgy, Jacques, Syed, Zainab, Goodall, Chris, El-Sheimy, Naser, Noureldin, Aboelmagd
• Primary Examiner(s): SMITH, JELANI A
• Application Number:
  US13/806,686
• Publication Number:
  US 20130211713A1
• Time in Patent Office: 1,884 Days
• Field of Search: 701/1, 701/16, 701/301, 701/469, 701/470, 701/472, 701/500, 701/518, 702/92, 702/153
• US Class Current: 1/1
• CPC Class Codes: G01S 19/47 the supplementary measurement being an inertial measurement, e.g. tightly coupled inertial
• CPC Class Codes: G01S 19/49 whereby the further system is an inertial position system, e.g. loosely-coupled
• CPC Class Codes: G01S 19/51 Relative positioning
• CPC Class Codes: H04B 10/00 Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication

Abstract

A moving platform INS range corrector (“MPIRC”) module and its method of operation for providing navigation and positioning information. The module comprises: means, such as a receiver, for receiving a first set of absolute navigational information from an external source (such as satellites in case of GNSS); an inertial sensor unit for generating a second set of navigational information at the module; and a transceiver, for receiving and/or transmitting signals and estimating distance measurement from a known position and receiving position coordinates. The navigational information is used by a processor programmed with a core algorithm, to produce a navigation solution (which comprises position, velocity and attitude). The system has the following attributes: the solution is produced seamlessly, even if one source of navigational information is temporarily out of service; the accuracy of the solution is assisted by use of distance and position coordinate measurement from a known position.

Claims

1. A method for combining different forms of navigational information, or a subset thereof, for producing a navigation solution of a first module, wherein the first module is operative to combine different forms of navigational information or a subset thereof, and enabled to communicate to at least one second module operative to combine different forms of navigational information or a subset thereof, wherein the first module and the at least one second module are mobile and the at least one second module has a variable position with respect to the first module, the method comprising:

a) obtaining readings from a sensor assembly of self-contained sensors within the first module and from a sensor assembly of self-contained sensors within the at least one second module, wherein the readings relate to navigational information of the first and at least one second modules, respectively, and producing outputs indicative thereof;

b) obtaining absolute navigational information for at least one of the first module and the at least one second module from external sources, and producing an output indicative thereof;

c) receiving and/or transmitting signals used to estimate ranging information between the first module and the at least one second module, wherein the estimated ranging information comprises a distance between the first module and the at least one second module determined from a measured characteristic of the signals, receiving and/or transmitting a navigation state of at least one of the first module and the at least one second module, and producing aiding signals comprising the estimated ranging information and the navigation state; and

d) providing at least one processor for processing at least the sensor assembly readings of the first module and the aiding signals to produce a navigation solution relating to the first module, wherein the at least one processor is configured to utilize the aiding signals to enhance the navigation solution when absolute navigation information for the first module is limited, degraded or denied or when the first module does not have absolute navigation capability.

2. The method of claim 1, wherein the sensor assembly of the first module comprises accelerometer means for measuring module specific forces and obtain accelerations and gyroscope means for measuring turning rates.

3. The method of claim 2, wherein the sensor assembly of the first module comprises at least two accelerometers and one gyroscope.

4. The method of claim 2, wherein the sensor assembly of the first module comprises three accelerometers and three gyroscopes.

5. The method of claim 1, wherein the absolute navigational information is obtained by a receiver.

6. The method of claim 5, wherein the receiver is a GNSS receiver.

7. The method of claim 6, wherein the GNSS receiver is a Global Positioning System receiver.

8. The method of claim 1, wherein the first module is positioned on a first platform, and the at least one second module is positioned on at least one second platform.

9. The method of claim 1, wherein the transceiver is a wireless or wired transceiver.

10. The method of claim 9, wherein the wireless transceiver uses signals appropriate to the transmission medium.

11. The method of claim 1, wherein the at least one processor is programmed to use a state estimation technique.

12. The method of claim 11, wherein the state estimation technique is linear or non-linear.

13. The method of claim 12, wherein the state estimation technique is an Extended Kalman Filter.

14. The method of claim 1, wherein the navigation solution is determined via a loosely or a tightly coupled integration scheme.

15. The method of claim 8, wherein the first platform is physically linked to at least one second platform.

16. The method of claim 15, wherein the physical link between the first platform and the at least one second platform enables the use of kinetic constraints that can be used to enhance the navigation solution of the first module.

17. The method of claim 15, wherein the physical link is a rigid link.

18. The method of claim 15, wherein the physical link is a non-rigid or flexible link.

19. A first module for producing a navigation solution, operative to combine different forms of navigational information, or a subset thereof, and enabled to communicate with at least one second module operative to combine different forms navigational information including from a sensor assembly of self-contained sensors within the at least one second module, or a subset thereof, wherein the first module and the at least one second module are mobile and the at least one second module has a variable position with respect to the first module, the first module comprising:

a) an assembly of self-contained sensors, within the first module, capable of obtaining readings relating to the navigational information of the first module, and producing an output indicative thereof;

b) a transceiver for receiving and/or transmitting signals used to estimate ranging information between the first module and the at least one second module, wherein the estimated ranging information comprises a distance between the first module and the at least one second module determined from a measured characteristic of the signals, receiving and/or transmitting a navigation state of at least one of the first module and the at least one second module, and for producing aiding signals comprising the estimated ranging information and the navigation state; and

c) at least one processor coupled to receive at least the sensor assembly readings and the aiding information to produce a navigation solution relating to the first module, wherein the at least one processor is configured to utilize the aiding information to enhance the navigation solution of the first module when absolute navigational information for the first module is limited, degraded or denied or when the first module does not have absolute navigation capability.

20. The first module of claim 19, wherein the sensor assembly of the first module comprises accelerometer means for measuring module specific forces and obtain accelerations and gyroscope means for measuring turning rates.

21. The first module of claim 20, wherein the sensor assembly of the first module comprises at least two accelerometers and one gyroscope.

22. The first module of claim 20, wherein the sensor assembly of the first module comprises three accelerometers and three gyroscopes.

23. The first module of claim 19, further comprising a receiver for obtaining the absolute navigational information.

24. The first module of claim 23, wherein the receiver is a GNSS receiver.

25. The first module of claim 24, wherein the GNSS receiver is a Global Positioning System receiver.

26. The first module in claim 19, wherein the first module is positioned on a first platform and the at least one second module is positioned on at least one second platform.

27. The first module of claim 19, wherein the transceiver is a wireless or wired transceiver.

28. The first module of claim 27, wherein the wireless transceiver uses signals appropriate to the transmission medium.

29. The first module of claim 19, wherein the at least one processor is programmed to use a state estimation technique.

30. The first module of claim 29, wherein the state estimation technique is linear or non-linear.

31. The first module of claim 30, wherein the state estimation technique is an Extended Kalman Filter.

32. The first module of claim 19, wherein the navigation solution is determined via a loosely or a tightly coupled integration scheme.

33. The first module in claim 26, wherein the first platform is physically linked to at least one second platform.

34. The first module in claim 33, wherein the physical link between the first platform and the at least one second platform enables the use of kinetic constraints that can be used to enhance the navigation solution of the first module.

35. The first module in claim 33, wherein the physical link is a rigid link.

36. The first module in claim 33, wherein the physical link is a non-rigid or flexible link.

37. A system for combining different forms of navigational information, or a subset thereof, comprising:

a mobile first module having a sensor assembly of self-contained sensors capable of obtaining readings relating to navigational information of the first module and a transceiver, wherein the first module is operative to combine different forms of navigational Information or subset thereof;

a mobile second module having a sensor assembly of self-contained sensors capable of obtaining readings relating to navigational information of the second module and a transceiver, wherein the second module is operative to combine different forms of navigational information or subset thereof;

a source of absolute navigation information for at least one of the first module and the second module; and

at least one processor;

wherein the first module and the second module have variable positions with respect to each other;

wherein the transceiver of the first module and the transceiver of the second module receive and/or transmit signals used to estimate ranging information between the first module and the second module, the estimated ranging information comprising a distance between the first module and the at least one second module determined from a measured characteristic of the signals, and receive and/or transmit a navigation state of at least one of the first module and the second module, and produce aiding signals comprising the estimated ranging information and the navigation state; and

wherein the at least one processor is configured to process the aiding signals and readings from at least one of the sensor assemblies of the first module and the second module to produce a navigation solution relating to a corresponding module, wherein the at least one processor is configured to utilize the aiding signals to enhance the navigation solution when absolute navigation information for the corresponding module is limited, degraded or denied or when the corresponding module does not have absolute navigation capability.