Surveying method

• US 9,109,890 B2
• Filed: 05/10/2011
• Issued: 08/18/2015
• Est. Priority Date: 05/10/2010
• Status: Active Grant

• Current Assignee: Leica Geosystems AG (Hexagon AB)
• Original Assignee: Leica Geosystems AG (Hexagon AB)
• Inventors: Metzler, Bernhard
• Primary Examiner(s): ELAHI, SHAN E
• Application Number:
  US13/639,772
• Publication Number:
  US 20130050474A1
• Time in Patent Office: 1,561 Days
• Field of Search: 348/135
• US Class Current: 1/1
• CPC Class Codes: G01C 1/04 combined with cameras
• CPC Class Codes: G01C 15/002 Active optical surveying means optical plumbing G01C15/105
• CPC Class Codes: G06V 20/653 by matching three-dimensional models, e.g. conformal mapping of Riemann surfaces

Abstract

A surveying method wherein an object belongs to a group of known types of objects, and determining an object representing point corresponding to the type of the object, including determining a series of points at an object by measuring distances and angles to the points in a defined angle area, analyzing the spatial distribution of the points and, based thereon, assigning relevant points to a first group of points, identifying the type of the object on the basis of the first group of points, capturing an image of the object, extracting a contour of the object from the image by use of an image processing method, fitting at least one space curve to the object on the basis of the first group of points and the extracted contour, and determining the coordinates of the object representing point from the fitted space curve.

Claims

1. A surveying method for measuring an object, wherein the object belongs to a group of known types of objects, and determining an object representing point corresponding to the type of the object, by a surveying instrument configured to measure distances and angles, and comprising a processor and a camera, the method comprising:

determining with the processor a series of points at the object by measuring distances and angles to the points in a defined angle area;

analyzing with the processor the spatial distribution of the points and, based thereon, identifying the type of the object and assigning relevant points lying on the object to a first group of points;

capturing an image of the object with the camera;

extracting a contour of the object from the image with the processor by use of an image processing method;

fitting with the processor at least one space curve to the object on the basis of the first group of points and the extracted contour; and

determining with the processor the coordinates of the object representing point from the fitted space curve,

wherein the series of points is split into at least a first group of relevant points presumably laying on the object and a second group of points by distances analysis and/or software algorithms executed by the processor, and at least one fitted line is calculated, which corresponds to the first group of points.

2. A surveying method according to claim 1, furthermore comprising the steps of:

aiming the surveying instrument at the object; and

automatically executing the surveying method.

3. A surveying method according to claim 1, wherein the series of points is split into at least a first group of relevant points presumably laying on the object and a second group of points laying in the background, by distances analysis and/or software algorithms with a Split-and-Marge and/or a Ransac method, and at least one fitted line is calculated, which corresponds to the first group of points.

4. A surveying method according to claim 1, wherein the series of points is split into at least a first group of relevant points and a second group of relevant points by distances analysis and/or software algorithms, in particular with a Split-and-Marge and/or a Ransac method, and at least two fitted line are calculated, the one fitted line corresponding to the first group of points and the second fitted line corresponding to the second group of points.

5. A surveying method according to claim 1, wherein a plane is defined by the extracted contour and a point at the surveying instrument, and an object representing point is determined as an intersection point between the plane and the fitted line.

6. A surveying method according to claim 1, wherein two planes are defined by the one point at the surveying instrument and the extracted contour.

7. A surveying method according to claim 1, wherein two planes are defined by the one point at the surveying instrument and the extracted contour, wherein the object is a mast and the contour comprises two straight lines, and an object representing point is determined corresponding to the space curve between the two planes.

8. A surveying method according to claim 1, wherein an object representing point is determined as an intersection point between at least one plane, said plane being defined by the extracted contour and the surveying instrument, and two fitted lines.

9. A surveying method according to claim 1, wherein a base point, given by a projection of the object representing point in a defined direction onto a ground surface is derived by image processing or is determined by using a vertical distance A, said vertical distance A being entered manually or being derived from an additional measurement on a perpendicular pole.

10. A surveying method according to claim 1, wherein a base point, given by a projection of the object representing point in a defined direction onto a ground surface vertically downwards is derived by edge detection or is determined by using a vertical distance A, said vertical distance A being entered manually or being derived from an additional measurement on a perpendicular pole.

11. A surveying method according to claim 1, wherein the series of points is projected onto a plane to determine whether the points are located on a plane object or on a cylindrical object or are not located on an object.

12. A surveying method according to claim 1, wherein object defining values are determined, in particular a radius of a cylindrical object is calculated.

13. A surveying method according to claim 12, wherein a radius of a cylindrical object is calculated with the processor.

14. A surveying method according to claim 1, wherein the surveying instrument is a total station or a total station comprising a remote control with a display.

15. A surveying method according to claim 1, wherein the coordinate data of the object representing point refer to a local coordinate system defined by the surveying instrument.

16. A surveying method according to claim 1, wherein the series of points comprises between 5 to 100 points.

17. A surveying instrument comprising a distance measuring unit, an angle determination unit, a camera and the processor for executing the surveying method corresponding to claim 1, wherein the surveying method is automatically executed.

18. A total station comprising a distance measuring unit, an angle determination unit, a camera and the processor for executing the surveying method corresponding to claim 1, wherein the surveying method is automatically executed.