System and method for calculating lever arm values photogrammetrically

• US 9,441,974 B2
• Filed: 03/15/2013
• Issued: 09/13/2016
• Est. Priority Date: 03/15/2013
• Status: Active Grant

• Current Assignee: Novatel Incorporated (Hexagon AB)
• Original Assignee: Novatel Incorporated (Hexagon AB)
• Inventors: Morin, Kristian, Dixon, Ryan
• Primary Examiner(s): Anyikire, Chikaodili E.
• Assistant Examiner(s): KALAPODAS, DRAMOS
• Application Number:
  US13/832,512
• Publication Number:
  US 20140267690A1
• Time in Patent Office: 1,278 Days
• US Class Current: 1/1
• CPC Class Codes: G01C 11/00 Photogrammetry or videogrammetry, e.g. stereogrammetry; Photographic surveying
• CPC Class Codes: G01C 11/06 by comparison of two or more pictures of the same area
• CPC Class Codes: G01C 21/1656 with passive imaging devices, e.g. cameras

Abstract

The inventive technique calculates lever arm values associated with a GNSS/INS system photogrammetrically. A calibrated camera on a device captures a plurality of images of the GNSS/INS system with the inclusion of a target, having known attributes and a plurality of control points. Thereafter, an application, executing on the device determines the lever arm values from the images of the GNSS/INS system utilizing the known attributes and the control points of the target. The INS may utilize the calculated lever arm values to combine information received from a GNSS receiver, of the GNSS/INS system, with information provided by sensors of the INS to compute updated positions, velocities, and/or orientations.

Claims

1. A system, comprising:

a calibrated camera configured to capture a plurality of images of a global navigation satellite system (GNSS)/inertial navigation system (INS) system, wherein each image includes a GNSS antenna of the GNSS/INS system, a reference point of the INS of the GNSS/INS system, and a target having known attributes and a plurality of control points; and

one or more processors configured to execute an application that provides instructions to determine lever arm values associated with the GNSS/INS system photogrammetrically based on the plurality of images of the GNSS/INS system and the known attributes and the plurality of control points of the target in the images.

2. The system of claim 1, wherein each image of the plurality of images is from a different vantage point of the GNSS/INS system.

3. The system of claim 1, the application is further configured to:

determine orientation information associated with each image of the GNSS/INS system utilizing the known attributes and the plurality of control points of the target;

determine a scale associated with each image utilizing the known attributes and the plurality of control points of the target, wherein the scale associated with each image is applied to each image;

determine x, y, and z coordinates of the GNSS antenna relative to the target and the reference point of the INS relative to the target utilizing the orientation information and the scale; and

determine the lever arm values based on the x, y, and z coordinates of the GNSS antenna and the reference point of the INS.

4. The system of claim 1, wherein the lever arm values are associated with a 3-dimensional vector between the reference point of the INS and the GNSS antenna.

5. The system of claim 1, wherein the instructions to determine the lever arm values include instructions to determine the lever arm values when the GNSS antenna is located on a roof of a vehicle and the INS is located inside the vehicle.

6. The system of claim 1, wherein the target is a pattern having at least three control points that define scale and orientation.

7. The system of claim 6, wherein the target is a checkerboard and the known attributes of the target are a size of the checkerboard and dimensions of each square on the checkerboard, and wherein the plurality of control points are points at which respective squares of the checkerboard intersect other squares on the checkerboard.

8. The system of claim 1, wherein the processor is further configured to:

transmit, over a network, the lever arm values to the GNSS/INS system, wherein the GNSS/INS system utilizes the lever arm values to combine information received from a GNSS receiver of the GNSS/INS system with the information provided by sensors of the INS to compute at least one of updated positions, updated velocities, and updated orientations.

9. The system of claim 1, wherein the reference point of the INS and the GNSS antenna are each marked with a marker.

10. A method, comprising:

receiving a plurality of images, captured by a calibrated camera, of a global navigation satellite system (GNSS)/inertial navigation system (INS) system, wherein each image includes a GNSS antenna of the GNSS/INS system, a reference point of the INS of the GNSS/INS system, and a target having known attributes and a plurality of control points; and

calculating, by a processor, the lever arm associated with the GNSS/INS system photogrammetrically based on the plurality of images of the GNSS/INS system and the known attributes and the plurality of control points of the target in the images.

11. The method of claim 10, wherein each of the plurality of images is from a different vantage point of the GNSS/INS system.

12. The method of claim 10, further comprising:

determining orientation information associated with each image of the GNSS/INS system utilizing the known attributes and the plurality of control points of the target;

determining a scale associated with each image utilizing the known attributes and the plurality of control points of the target, wherein the scale for each image is applied to each image;

determining x, y, and z coordinates of the GNSS antenna relative to the target and the reference point of the INS relative to the target utilizing the orientation information and the scale; and

determining the lever arm values based on the x, y, and z coordinates of the GNN antenna and the reference point of the INS.

13. The method of claim 10, wherein the lever arm values are associated with a 3-dimensional vector between the reference point of the INS and the GNSS antenna.

14. The method of claim 10, wherein the GNSS antenna is located on a roof of a vehicle and the INS is located inside the vehicle.

15. The method of claim 10, wherein the target is a pattern having at least three control points that define scale and orientation.

16. The method of claim 15, wherein the target is a checkerboard and the known attributes of the target are a size of the target and dimensions of each square on the checkerboard, and wherein the plurality of control points are points at which respective squares of the checkerboard intersect other squares on the checkerboard.

17. The method of claim 10, further comprising:

transmitting, over a network, the lever arm values to the GNSS/INS system, wherein the GNSS/INS system utilizes the lever arm values to combine information received from a GNSS receiver of the GNSS/INS system with the information provided by sensors of the INS to compute at least one of updated positions, updated velocities, and updated orientations.

18. The method of claim 10, further comprising:

utilizing a graphical user interface to mark, from within an application, the reference point of the INS and the GNSS antenna with an indicator; and

recognizing, by the application, the reference point of the INS and the GNSS antenna based on the indicators.

19. The method of claim 10, further comprising:

recognizing, by an application, the reference point of the INS and the GNSS antenna based on a marker physically placed on the reference point of the INS and the GNSS antenna.

20. The method of claim 10, wherein the INS is the target having the known attributes and the plurality of control points.

21. A system, comprising:

a calibrated camera configured to capture a plurality of images of a global navigation satellite system (GNSS)/inertial navigation system (INS) system, wherein each image includes a GNSS antenna of the GNSS/INS system, a reference point of the INS of the GNSS/INS system, and a target having known attributes and a plurality of control points; and

one or more processors configured to;

determine orientation information associated with each image of the GNSS/INS system utilizing the known attributes and the plurality of control points of the target,

determine a scale associated with each image utilizing the known attributes and the plurality of control points of the target, wherein the scale associated with each image is applied to each image, and

determine a 3-dimensional vector between the reference point of the INS and the GNSS antenna based on the x, y, and z coordinates of the GNSS antenna and the reference point of the INS.