Position measuring system, position measuring method and position measuring program

• US 20080075325A1
• Filed: 08/10/2007
• Published: 03/27/2008
• Est. Priority Date: 09/22/2006
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Topcon
• Original Assignee: Kabushiki Kaisha Topcon
• Inventors: Ito, Tadayuki, Otani, Hitoshi
• Granted Patent: US 8,218,131 B2
• Time in Patent Office: Days
• US Class Current: 382/106
• CPC Class Codes: G01C 15/002 Active optical surveying means optical plumbing G01C15/105

Abstract

A position measuring system, comprising a distance measuring unit for projecting and scanning a pulsed beam for measurement to a measurement area and for measuring a distance based on a reflected light of the pulsed beam for measurement and for obtaining a position data group in the measurement area, a digital image pickup unit for acquiring an image data by taking an image of the measurement area, a storage unit for storing at least two sets of the position data groups and the image data acquired from at least two directions by interrelating and associating the position data groups with the image data, and an arithmetic unit for synthesizing the at least two position data groups through matching of the two images based on the two stored image data.

Claims

1. A position measuring system, comprising a distance measuring unit for projecting and scanning a pulsed beam for measurement to a measurement area and for measuring a distance based on a reflected light of the pulsed beam for measurement and for obtaining a position data group in the measurement area, a digital image pickup unit for acquiring an image data by taking an image of the measurement area, a storage unit for storing at least two sets of the position data groups and the image data acquired from at least two directions by interrelating and associating the position data groups with the image data, and an arithmetic unit for synthesizing the at least two position data groups through matching of the two images based on the two stored image data.

2. A position measuring system according to claim 1, further comprising a sight, wherein said arithmetic unit sets up said measurement area by using said sight, wherein, in the case where the measurement area extends beyond a range of a single image pickup, said arithmetic unit calculates a dividing aspect, picks up divided images two or more times, synthesizes the divided images, and obtains an image of the measurement area.

3. A position measuring system according to claim 1, wherein said arithmetic unit prepares polygonal meshes from said position data group, and the polygonal meshes are interrelated and associated with the image data.

4. A position measuring system according to claim 1, wherein said arithmetic unit approximately sets up at least three points or more common to said two image data, and, after performing coordinate transformation on one of the images with reference to the three points or more, matching is performed on said two images, and coordinate transformation is further conducted by using the coordinates obtained by said image matching.

5. A position measuring system according to claim 1, wherein said arithmetic unit approximately sets up three points or more common to said two image data, sets up a template for an area as required including common points in one of the images, sets up a search area which is larger than said template in the other of the images so that the common points are included, and performs image matching by least squares matching method on the images of said template and the image of the search area.

6. A position measuring system according to claim 4, wherein said arithmetic unit sets up at least three points or more common to the position data groups when two or more position data groups are to be synthesized, performs coordinate transformation by using all of the position data groups with reference to said points, and adjusts the synthesis of total position data groups.

7. A position measuring method, comprising a first step of projecting and scanning a pulsed beam for measurement to a measurement area and obtaining a position data group in the measurement area by performing distance measurement based on a reflected light of the pulsed beam for measurement, a second step of taking an image of said measurement area and acquiring an image data, a third step of storing at least two sets of the position data groups and the image data acquired from at least two directions by interrelating and associating the position data groups with the image data, and a fourth step of synthesizing the two image data groups through matching of two images based on the stored two image data.

8. A position measuring method according to claim 7, wherein polygonal meshes are prepared from said position data group for the interrelating and the associating of the position data group with the image data, and the polygonal meshes are interrelated and associated with the image data.

9. A position measuring method according to claim 7, further comprising a step of approximately setting up at least three points or more common to the two image data, and, after performing coordinate transformation of one of the images with reference to the three points or more, performing the matching of the two images, and conducting coordinate transformation further by the coordinates obtained by the image matching.

10. A position measuring method according to claim 7, further comprising a step of approximately setting up three points or more common to the two image data for the matching, setting a template of an area as required including the common points in one of the images, setting up a search area larger than said template including the common points in the other of the images, and performing image matching by least squares matching method on the image of said template and on the image of said search area.

11. A position measuring method according to claim 9, wherein, in said coordinate transformation, when two or more position data groups are to be synthesized, at least three points or more common to the position data groups are set up, coordinate transformation is performed by using all of the position data groups with reference to said points, and synthesis of total position data groups is adjusted.

12. A position measuring program for executing a step of projecting and scanning a pulsed beam for measurement to a measurement area, a step of measuring a distance based on a reflected light of the pulsed beam for measurement, a step of obtaining position data group on the measurement area, a step of acquiring image data by taking an image of the measurement area, a step of storing at least two sets of said position data group and said image data acquired from at least two directions by interrelating and associating the position data group with the image data, and a step of synthesizing two position data groups through matching of two images based on two stored image data.

13. A position measuring program according to claim 12, wherein polygonal meshes are prepared from the position data group for the interrelating and the associating of the position data groups with the image data, and the polygonal meshes are interrelated and associated with the image data.

14. A position measuring program according to claim 12, wherein at least three points or more common to the two image data are approximately set up, and, after performing coordinate transformation on one of the images with reference to the three points or more, matching is performed on the two images, and coordinate transformation is further executed by the coordinates obtained by the image matching.

15. A position measuring program according to claim 12, wherein three points or more common to said two image data are approximately set up for the matching, a template of an area as required including the common points is set up in one of the images, a search area larger than said template including the common points is set up in the other of the images, and image matching by least squares matching method is performed on the image of said template and on the image of said search area.

16. A position measuring program according to claim 14, wherein at least three or more points common to the position data groups are set up in said coordinates transformation when two or more position data groups are to be synthesized, and coordinate transformation is performed by using all of the position data groups with reference to the points, and synthesis of total position data groups is adjusted.