Position measuring method and position measuring instrument

• US 8,224,030 B2
• Filed: 06/29/2010
• Issued: 07/17/2012
• Est. Priority Date: 07/17/2009
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Topcon
• Original Assignee: Kabushiki Kaisha Topcon
• Inventors: Otani, Hitoshi, Kumagai, Kaoru
• Primary Examiner(s): Wang, Claire X
• Application Number:
  US12/825,750
• Publication Number:
  US 20110158475A1
• Time in Patent Office: 749 Days
• Field of Search: 382/103, 382/284, 348/135, 701/523
• US Class Current: 382/103
• CPC Class Codes: G01C 11/30 by triangulation
• CPC Class Codes: G01C 21/005 with correlation of navigation data from several sources, e.g. map or contour matching G01C21/30 takes precedence

Abstract

The present invention provides a position measuring instrument, comprising a GPS position detecting device 7, an image pickup device 9 for continuously taking a digital image, a laser distance measuring device 8, and a measuring instrument main unit 2, wherein the GPS position detecting device measures positional data at a first point and a second point, the image pickup device continuously takes digital images on sceneries in surroundings during a process where the image pickup device moves from the first point, which is a known point, via the second point to a third point, which is an unknown point, the laser distance measuring device measures a distance to the object of image pickup in parallel to the image pickup by the image pickup device, and the measuring instrument main unit generates tracking point from the image obtained at the first point, sequentially identifies the tracking points from the tracing of points generated on the images to be acquired continuously, calculates three-dimensional positional data of the tracking points of the images acquired at the first point and the images acquired at the second point from the positional data at the first point and the second point, compares the result of calculation with the result of distance measurement by the laser distance measuring device, adopts the result of calculation within a predetermined limit of errors with respect to the measurement results as positional data of the tracking point, and calculates positional data of the third point from the positional data of the tracking point.

Claims

1. A position measuring method for measuring a moving image pickup position and for measuring an object of image pickup from the image pickup position, wherein a method of intersection and a method of resection are alternately and repeatedly carried out, said method of intersection is used to continuously take digital images, to generate tracking point in the image, to perform tracking on moving image and to measure coordinates of said tracking point from coordinates of the image pickup position used as a known point by calculation, said method of resection is used to measure the image pickup position after moving from coordinates of the tracking point obtained by calculation, comprising a step of measuring actually a distance to an object of image pickup by laser surveying in parallel to image pickup of the digital image, a step of comparing coordinates of said tracking point obtained by calculation with the distance obtained by actual measurement, and a step of acquiring a calculating coordinate as coordinate value of the tracking point in case said calculating coordinate obtained by calculation is within a predetermined limit of errors to the actually measured distance.

2. A position measuring method according to claim 1, further comprising a step of moving a plurality of points in up-to-bottom direction while performing laser surveying, and a step of setting a range of measurement for performing the tracking of the moving image.

3. A position measuring method according to claim 1, further comprising a step of including road surface or ground surface in a part of the moving image to be taken, a step of extracting the tracking point also from images of said road surface or said ground surface, and a step of continuing tracking of the moving image by the images of said road surface or said ground surface when the object of image pickup is not present.

4. A position measuring instrument, comprising a GPS position detecting device, an image pickup device for continuously taking a digital image, a laser distance measuring device, and a measuring instrument main unit, wherein said GPS position detecting device measures positional data at a first point and a second point, said image pickup device continuously takes digital images on sceneries in surroundings during a process where the image pickup device moves from the first point, which is a known point, via the second point to a third point, which is an unknown point, said laser distance measuring device measures a distance to the object of image pickup in parallel to the image pickup by said image pickup device, and said measuring instrument main unit generates tracking point from the image obtained at the first point, sequentially identifies said tracking points from the tracing of points generated on the images to be acquired continuously, calculates three-dimensional positional data of the tracking points of the images acquired at the first point and the images acquired at the second point from the positional data at the first point and the second point, compares the result of calculation with the result of distance measurement by said laser distance measuring device, adopts the result of calculation within a predetermined limit of errors with respect to said measurement results as positional data of said tracking point, and calculates positional data of said third point from the positional data of said tracking point.

5. A position measuring instrument according to claim 4, wherein said laser distance measuring device can perform measurements on a plurality of points in up-to-bottom direction at the same time or almost at the same time.

6. A position measuring instrument according to claim 4, wherein said laser distance measuring device projects a plurality of pulsed laser beams with aligned along a line in up-to-bottom direction with a predetermined distance between them, and distance measurement is performed for each laser beam and for each pulse of each laser beam.

7. A position measuring instrument according to claim 4, wherein said laser distance measuring device projects a single pulsed laser beam reciprocally in up-to-bottom direction for scanning, and measures distance for each pulse.

8. A position measuring instrument according to one of claims 5 to 7, wherein said measuring instrument main unit sets up a range of measurement based on the result of measurement by said laser distance measuring device and carries out tracking on the moving image and measurement on said range of measurement.