PHOTOGRAMMETRIC NETWORKS FOR POSITIONAL ACCURACY

• US 20130128037A1
• Filed: 08/20/2012
• Published: 05/23/2013
• Est. Priority Date: 09/28/2007
• Status: Active Grant

• Current Assignee: Zoom Information Systems
• Original Assignee: Zoom Information Systems
• Inventors: Westrick, William A., Apter, Elena
• Granted Patent: US 8,817,093 B2
• Time in Patent Office: Days
• US Class Current: 348/140
• CPC Class Codes: G01C 11/02 Picture taking arrangements specially adapted for photogrammetry or photographic surveying, e.g. controlling overlapping of pictures
• CPC Class Codes: G01C 11/04 Interpretation of pictures
• CPC Class Codes: G01C 7/04 involving a vehicle which moves along the profile to be traced
• CPC Class Codes: G01S 19/47 the supplementary measurement being an inertial measurement, e.g. tightly coupled inertial
• CPC Class Codes: G06T 7/70 Determining position or orientation of objects or cameras camera calibration G06T7/80
• CPC Class Codes: G06T 7/73 using feature-based methods
• CPC Class Codes: H04N 7/18 Closed-circuit television [CCTV] systems, i.e. systems in which the video signal is not broadcast

Abstract

The present invention involves a surveying system and method which determines the position of an object point using two images. First, at least two reference points appearing on the two images are correlated. Then the position of the object point is determined based on the two images and the two reference points.

Claims

1. A method of surveying objects, the method comprising:

with a mobile survey system, collecting capture point data at at least two capture points corresponding to mobile survey system positions, the capture point data including three non-collinear reference points operable to orient the capture point data, the reference points corresponding to objects surveyed by the mobile survey system;

calculating the positions of the at least two capture points and the positions of the reference points relative to the position of the corresponding capture point;

correlating the reference points to identify correlated reference points;

weighing the positions of the correlated reference points based on error functions computed for each of the at least two capture points to determine correlation points; and

recalculating the positions of the at least two capture points so that the positions of the reference points match the correlation points.

2. A method as in claim 1, wherein collecting capture point data at the at least two capture points comprises collecting imagery data.

3. A method as in claim 2, wherein the mobile survey system includes two cameras operable to collect the imagery data.

4. A method as in claim 1, wherein calculating the positions of the at least two capture points comprises obtaining global positioning data with a global positioning system.

5. A method as in claim 4, wherein calculating the positions of the at least two capture points further comprises obtaining inertial navigation system data.

6. A method as in claim 1, further comprising creating a rigid mesh over a surveyed area based on the recalculated positions of the at least two capture points.

7. A method as in claim 6, further comprising pinning the rigid mesh to points with known low positional error.

8. A method as in claim 1, further comprising reducing a total survey error of a survey conducted over a surveyed area based on the recalculated positions of the at least two capture points.

9. A machine-readable product comprising instructions operable to cause a computing device to perform a method of surveying objects with a mobile survey system, the method comprising:

collecting capture point data at at least two capture points corresponding to mobile survey system positions, the capture point data including three non-collinear reference points operable to orient the capture point data, the reference points corresponding to objects surveyed by the mobile survey system;

calculating the positions of the at least two capture points and the positions of the reference points relative to the position of the corresponding capture point;

correlating the reference points to identify correlated reference points;

weighing the positions of the correlated reference points based on error functions computed for each of the at least two capture points to determine correlation points; and

recalculating the positions of the at least two capture points so that the positions of the reference points match the correlation points.

10. A machine-readable product as in claim 9, wherein collecting capture point data at the at least two capture points comprises collecting imagery data.

11. A machine-readable product as in claim 10, wherein the mobile survey system includes two cameras operable to collect the imagery data.

12. A machine-readable product as in claim 9, wherein calculating the positions of the at least two capture points comprises obtaining global positioning data with a global positioning system.

13. A machine-readable product as in claim 12, wherein calculating the positions of the at least two capture points further comprises obtaining inertial navigation system data.

14. A machine-readable product as in claim 9, further comprising creating a rigid mesh over a surveyed area based on the recalculated positions of the at least two capture points.

15. A machine-readable product as in claim 14, further comprising pinning the rigid mesh to points with known low positional error.

16. A machine-readable product as in claim 9, further comprising reducing a total survey error of a survey conducted over a surveyed area based on the recalculated positions of the at least two capture points.

17. A system for surveying objects, the system comprising:

a mobile survey system comprising sensory devices supported by the mobile survey system and configured to collect capture point data at at least two capture points corresponding to mobile survey system positions, the capture point data including three non-collinear reference points operable to orient the capture point data, the reference points corresponding to objects surveyed by the mobile survey system; and

a computing device communicatively coupled to the mobile survey system and configured to;

calculate the positions of the at least two capture points and the positions of the reference points relative to the position of the corresponding capture point;

correlate the reference points to identify correlated reference points;

weigh the positions of the correlated reference points based on error functions computed for each of the at least two capture points to determine correlation points; and

recalculate the positions of the at least two capture points so that the positions of the reference points match the correlation points.

18. A system as in claim 17, wherein the sensory devices comprise two cameras operable to collect imagery data.

19. A system as in claim 18, wherein the mobile survey system includes a global positioning system operable to calculate the positions of the at least two capture points.

20. A system as in claim 19, wherein the mobile survey system includes an inertial navigation system operable to calculate the positions of the at least two capture points.