Geodesic measuring device comprising a thermographic camera

Patent metadata

Field	Value
Publication number	US-9733081-B2
Application number	US-201213978737-A
Country	US
Kind code	B2
Filing date	Jan 10, 2012
Priority date	Jan 10, 2011
Publication date	Aug 15, 2017
Grant date	Aug 15, 2017

Abstract

Method for determining, with geodesic precision, the position of a target point on a target object by using a geodesic measuring device, said method comprising a sighting device which comprises at least one objective unit that defines an optical line of sight, an electronic distance measuring unit, and a thermal imaging camera for recording a thermal image in the direction of the optical line of sight. An angle measuring function is provided for recording the line of sight alignment, and a control unit is provided for controlling the angle measuring function, the thermal imaging camera. In a thermal imaging mode when a measurement procedure is triggered, position data of the sighted target point which are determined in said measurement procedure are linked to temperature information which is read out from the thermal image for the target point at which the line of sight is aimed.

First claim

What is claimed is:

1. A method for determining the coordinates and temperature information of a target point on a target object using a geodesic measuring device being a total station or a theodolite, the geodesic measuring device comprising:
a base;
a sighting device rotationally coupled with the base, wherein the sighting device is pivotable on a first axis and a second axis relative to the base of the geodesic measuring device in order to change the alignment thereof and the sighting device includes:
an objective unit that defines an optical aiming axis;
an electronic laser distance measuring unit configured for providing a distance measuring functionality for determining distances with respect to the target point; and
a thermal imaging camera for acquiring a thermal image in the direction of the optical aiming axis;

an angle measuring functionality for acquiring the alignment of the aiming axis; and
a control unit for controlling the angle measuring functionality and the thermal imaging camera, the method comprising:
acquiring a thermal image;
obtaining temperature information from the thermal image automatically using image processing;
deriving coordinates with respect to the target point on the target object from the angle measuring functionality and distance measuring functionality; and
determining distances and angles of positions within the thermal image from the thermal image and the coordinates, wherein at least some of the positions within the thermal image are of the sighted target point, wherein distances and temperature information are linked to one another in pairs in such a way that they can be called up in a manner associated with one another,
wherein coordinates of the sighted target point are stored in a manner correlated with the temperature information,
wherein positions of the temperature information on the thermal image correspond to coordinates of the sighted target point defined by the alignment of the optical aiming axis.

2. The method as claimed in claim 1 , wherein a target point on the target object acquired in the thermal image is measured on the basis of a temperature measurement criterion predefined depending on the temperature information which can be read out from the thermal image, wherein the optical aiming axis of the measuring device is aligned with the target point, wherein the position data of the target point are stored in a manner correlated with the temperature information.

3. The method as claimed in claim 2 , wherein in order to define the temperature measurement criterion, the temperature information in the thermal image is converted into areas each representing a temperature range, wherein the areas are delimited with respect to one another by isotherms, and/or a center of a temperature range is determined.

4. The method as claimed in claim 2 , wherein in order to define the temperature measurement criterion, the temperature information in the thermal image is converted into areas each representing a temperature range, wherein the areas are delimited with respect to one another by isotherms, and/or an area centroid is determined.

5. The method as claimed in claim 2 , wherein measurement is effected along a path representing predetermined temperature information or a defined temperature profile.

6. The method as claimed in claim 5 , wherein measurement is effected automatically with a predetermined point-to-point resolution and/or with a predetermined temporal separation of individual measurements.

7. The method as claimed in claim 5 , wherein the measurement is effected along a path representing predetermined temperature information or a defined temperature profile along the isotherms, and/or constantly with respect to a point of the predetermined temperature information with respect to the center of the temperature range.

8. The method as claimed in claim 2 , wherein a reference beam is guided along a reference path, wherein, during the guidance of the reference beam, at least one part of the reference path is perceptible on the object as a reference line visually and/or by means of a detector and the reference beam is guided on the basis of the temperature measurement criterion along the isotherms.

9. The method as claimed in claim 1 , wherein:
the temperature information and a corresponding daylight image are represented independently of one another and/or in a manner at least partly superimposed on an output unit;
and/or acquired data and/or information are/is communicated to a controller, wherein the acquired data and/or temperature information are/is represented at the controller.

10. The method as claimed in claim 1 , wherein coordinates with respect to the target point on the target object are determined and extracted and the coordinates are transmitted into a computer unit, wherein measurements of distances and angles in the acquired thermal image are carried out on the basis of the coordinates.

11. The method as claimed in claim 1 , wherein coordinates with respect to the target point on the target object are determined and extracted and the coordinates are transmitted into a CAD system, wherein measurements of distances and angles in the acquired thermal image can be carried out on the basis of the coordinates.

12. The method as claimed in claim 1 , wherein the sighting device includes a telescopic sight and the control unit controls the alignment of the sighting unit.

13. The method as claimed in claim 1 , wherein a target point on the target object acquired in the thermal image is measured automatically on the basis of a temperature measurement criterion predefined depending on the temperature information which can be read out from the thermal image, wherein the optical aiming axis of the measuring device is aligned with the target point.

14. A geodesic measuring device for determining position data and temperature information of a target point on a target object, the geodesic measuring device being a total station or a theodolite comprising:
a base;
a sighting device rotationally coupled with the base, wherein the sighting device is pivotable on a first axis and a second axis relative to the base of the geodesic measuring device in order to change the alignment thereof and this sighting device includes:
an objective unit that defines an optical aiming axis;
an electronic laser distance measuring unit configured for providing a distance measuring functionality for determining distances with respect to the target point; and
a thermal imaging camera for acquiring a thermal image in the direction of the optical aiming axis; and
an angle measuring functionality for acquiring the alignment of the aiming axis; and

a control unit for controlling the angle measuring functionality and the thermal imaging camera,
wherein in the context of a thermal image measurement mode under the control of the control unit, as a result of the initiation of a measurement process, position data of the sighted target point which are determined, together with temperature information read out from the thermal image for the target point sighted using the aiming axis, are linked to one another in pairs in such a way that they can be called up in a manner associated with one another,
wherein the position data of the sighted target point are stored in a manner correlated with the temperature information,
wherein the temperature information is read from the thermal image automatically using image processing, and
wherein a distance measurement is effected with the laser distance measuring unit along a path representing temperature boundaries determined by the thermal imaging camera or a d

Assignees

• Zimmermann Jan
• Kotzur Norbert
• Möller Bernd
• Sieber Stefan
• Legrand Vincent
• Leica Geosystems Ag

Inventors

• Zimmermann Jan
• Kotzur Norbert
• Möller Bernd
• Sieber Stefan
• Legrand Vincent

Classifications

• G01C15/06

  Surveyors' staffs; Movable markers · CPC title

• G01C7/00

  Tracing profiles (by photogrammetry or videogrammetry G01C11/00) · CPC title

• G01C1/04 Primary

  combined with cameras · CPC title

• G01C15/00 Primary

  Surveying instruments or accessories not provided for in groups G01C1/00 - G01C13/00 · CPC title