Surveying system

Patent metadata

Field	Value
Publication number	US-10655962-B2
Application number	US-201615373226-A
Country	US
Kind code	B2
Filing date	Dec 8, 2016
Priority date	May 5, 2014
Publication date	May 19, 2020
Grant date	May 19, 2020

Abstract

A system is disclosed that comprises a camera module and a control and evaluation unit. The camera module is designed to be attached to the surveying pole and comprises at least one camera for capturing images. The control and evaluation unit has stored a program with program code so as to control and execute a functionality in which a series of images of the surrounding is captured with the at least one camera; a SLAM-evaluation with a defined algorithm using the series of images is performed, wherein a reference point field is built up and poses for the captured images are determined; and, based on the determined poses, a point cloud comprising 3D-positions of points of the surrounding can be computed by forward intersection using the series of images, particularly by using dense matching algorithm.

First claim

The invention claimed is:

1. A surveying subsystem adapted to be used as part of a surveying system that is adapted to determine positions of a position measuring resource that is mounted on a surveying pole and includes a GNSS-antenna or a retro-reflector, wherein said surveying pole is hand-carried, the surveying subsystem comprising:
a camera module configured to be attached to the surveying pole and having a camera and an optical element, the optical element being configured such that the camera has an angle of view of 360° in an azimuthal direction; and
a control and evaluation unit having stored thereon a program with program code that, when executed, controls and executes a spatial representation generation functionality in which, when moving along a path through a surrounding:
a first series of panoramic images of the surrounding is captured with the camera, the first series comprising an amount of panoramic images captured with different poses of the camera, the poses representing respective positions and orientations of the camera,
a SLAM-evaluation with a defined algorithm using the series of panoramic images is performed, wherein a plurality of respectively corresponding image points are identified in each of several sub-groups of panoramic images of the series of panoramic images and, based on resection and forward intersection using the plurality of respectively corresponding image points,
a reference point field is built up comprising a plurality of reference points of the surrounding, wherein coordinates of the reference points are derived, and
the poses for the panoramic images are determined,

wherein a position and orientation of at least one of the surveying subsystem or the camera in six degrees of freedom are derived based on one or more of the determined poses and based on a multitude of determined positions of the position measuring resource.

2. The surveying subsystem according to claim 1 , wherein:
the control and evaluation unit is configured so that the spatial representation generation functionality is controlled and executed in such a way, that the reference point field forms a sparse point cloud that serves for determination of the poses of the camera/s and thus expressly for localisation purposes and,
based on the determined poses, a dense point cloud that includes 3D-positions of points of the surrounding is computed by forward intersection using the images of the first series of images and images of a second series of images.

3. The surveying subsystem according to claim 2 , wherein,
the control and evaluation unit is configured so that the spatial representation generation functionality is controlled and executed in such a way, that:
determined positions of the position measuring resource for points that have been adopted on the path are received by the control and evaluation unit from the surveying system; and
the dense point cloud is scaled, and particularly geo-referenced, with help of the received determined positions.

4. The surveying subsystem according to claim 2 , wherein,
the control and evaluation unit is configured so that the spatial representation generation functionality is controlled and executed in such a way, that a graphical reproduction is generated for the dense point cloud, the graphical reproduction being displayable by display means of the surveying system.

5. The surveying subsystem according to any claim 1 , wherein,
the position measuring resource comprises a GNSS-antenna or a retro-reflector.

6. The surveying subsystem according to any one of claim 1 , wherein,
orientations of at least one camera in six degrees of freedom are derived based on:
one or more of the determined poses; and
data from an inertial measuring unit of the camera module.

7. A surveying system comprising:
a hand-carried surveying pole,
a position measuring resource being mounted on the surveying pole, wherein positions of the position measuring resource are determinable by the surveying system, and
a surveying subsystem according to claim 1 .

8. The surveying system according to claim 7 , wherein,
the position measuring resource comprises a GNSS-antenna or a retro-reflector.

9. The surveying subsystem according to claim 1 , wherein, the optical element comprises a mirroring surface in form of a cone, a sphere or a curvature.

10. The surveying subsystem according to claim 1 , wherein, the camera and the optical element are arranged and designed so that a surrounding to be captured is projected onto a sensor of the camera so that an image of the surrounding is provided with substantially identically sized pieces of the image covering substantially identically sized parts of the surrounding, thus providing for an image representing the captured surrounding in homogenous reproduction.

11. A surveying subsystem adapted to be used as part of a surveying system that is adapted to determine positions of a position measuring resource that is mounted on a surveying pole and includes a GNSS-antenna or a retro-reflector, wherein said surveying pole is hand-carried, the surveying subsystem comprising:
a camera module configured to be attached to the surveying pole and having a camera and an optical element, the optical element being configured such that the camera has an angle of view of 360° in an azimuthal direction; and
a control and evaluation unit having stored thereon a program with program code that, when executed, controls and executes a spatial representation generation functionality in which, when moving along a path through a surrounding:
a first series of panoramic images of the surrounding is captured with the camera, the first series comprising an amount of panoramic images captured with different poses of the camera, the poses representing respective positions and orientations of the camera,
a SLAM-evaluation with a defined algorithm using the series of panoramic images is performed, wherein a plurality of respectively corresponding image points are identified in each of several sub-groups of panoramic images of the series of panoramic images and, based on resection and forward intersection using the plurality of respectively corresponding image points,
a reference point field is built up comprising a plurality of reference points of the surrounding, wherein coordinates of the reference points are derived, and

the poses for the panoramic images are determined,
wherein a position and orientation of at least one of the surveying subsystem or the camera in six degrees of freedom are derived based on one or more of the determined poses and based on a traveling history for the moved path.

12. The surveying subsystem according to claim 11 , wherein, the optical element comprises a mirroring surface in form of a cone, a sphere or a curvature.

13. The surveying subsystem according to claim 11 , wherein, the camera and the optical element are arranged and designed so that a surrounding to be captured is projected onto a sensor of the camera so that an image of the surrounding is provided with substantially identically sized pieces of the image covering substantially identically sized parts of the surrounding, thus providing for an image representing the captured surrounding in homogenous reproduction.

14. The surveying subsystem according to claim 11 , wherein:
the control and evaluation unit is configured so that the spatial representation generation functionality is controlled and executed in such a way, that the reference point field forms a sparse point cloud that serves for determination of the poses of the camera/s and thus expressly for localisation purposes and,
base

Assignees

• Hexagon Technology Ct Gmbh

Inventors

• Siercks Knut
• Metzler Bernhard
• Van Der Zwan Elmar Vincent
• Fidler Thomas
• Parys Roman
• Velizhev Alexander
• Scheja Jochen

Classifications

• G01C11/04 Primary

  Interpretation of pictures · CPC title

• G06T7/0004

  Industrial image inspection · CPC title

• G06T7/97

  Determining parameters from multiple pictures (depth or shape recovery from multiple images G06T7/55; stereo camera calibration G06T7/85) · CPC title

• G01C15/006 Primary

  Detectors therefor · CPC title

• G01C15/002 Primary

  Active optical surveying means (optical plumbing G01C15/105) · CPC title