Surveying device comprising height measuring system and method for measuring a height

Patent metadata

Field	Value
Publication number	US-10890446-B2
Application number	US-201715640132-A
Country	US
Kind code	B2
Filing date	Jun 30, 2017
Priority date	Jun 30, 2016
Publication date	Jan 12, 2021
Grant date	Jan 12, 2021

Abstract

A surveying device for determining the position of a target, comprising a means for orienting a target axis of the surveying device towards the target point, an angle-measuring functionality for the highly precise detection of the orientation of the target axis, and evaluation means for data storage, a height measuring system for determining a height of the surveying device above the ground by means of triangulation, wherein the height measuring system comprises at least one laser plummet for emitting a laser beam along a standing axis of the surveying device onto a ground point, and a detection unit comprising a line sensor for detecting a diffuse backscattering of the laser beam, and wherein the height measuring system for determining a height of the surveying device above the ground point is designed based on a position of the diffuse backscattering on the line sensor.

First claim

What is claimed is:

1. A surveying device for determining the position of a target point, the surveying device comprising:
a means for orienting a target axis of the surveying device towards the target point;
an angle-measuring functionality for the highly precise detection of the orientation of the target axis;
an evaluation means for data storage; and
a height measuring system for determining a height of the surveying device above the ground by means of triangulation, wherein the height measuring system comprises:
a laser plummet for emitting a laser beam along a standing axis of the surveying device onto a ground point, and
a detection unit comprising a line sensor for detecting a diffuse backscattering of the laser beam,

wherein the height measuring system is designed for determining a height of the surveying device above the ground point based on a position of the diffuse backscattering on the line sensor, and
wherein the height measuring system comprises a line laser unit for projecting a linear laser marking onto the ground, and
the detection unit comprises a linear viewing field for detecting the diffuse backscattering of the laser beam, and the line sensor is designed for at least partially detecting the linear laser marking,
wherein the height measuring system is designed for deriving an intensity profile based on the detected linear laser marking on the ground and, based thereon, detecting a size, a relative position, or a type of a standardized ground target located on the ground.

2. The surveying device according to claim 1 , wherein the surveying device is a geodetic surveying device, a theodolite, a total station, or a laser scanner, comprising:
a base;
a support which is rotatable relative to the base about a standing axis; and
a targeting device which is swivels relative to the support about a transverse axis and comprises an objective unit defining an optical target axis.

3. The surveying device according to claim 1 , wherein the detection unit and the laser plummet are situated with respect to each other in such a way that the height measuring system meets the Scheimpflug condition.

4. The surveying device according to claim 1 , wherein the line sensor and the line laser unit are situated on the surveying device in such a way that they can be jointly rotated through at least 1800 about the standing axis, wherein within the scope of a functionality for determining a distance or a three-dimensional offset of an origin of a local coordinate system of the surveying device from a standardized ground target located on the ground, and wherein: the line laser unit is designed for projecting a linear laser marking onto the ground, the line sensor is designed for detecting the diffuse backscattering of the linear laser marking with a high measuring frequency from a plurality of different positions, and the height measuring system is designed for deriving a plurality of intensity profiles based on the detected diffuse backscatterings of the linear laser marking and of deriving a position of the ground target based on the plurality of intensity profiles.

5. A surveying device according to claim 1 , further comprising: a camera which is designed for detecting:
a standardized ground target by means of image recognition, or
a known supplementary ground target located on the ground by means of image recognition,
and which is assigning the detection to a data record stored in a memory, which includes at least data regarding the spatial extension of the standardized ground target or the supplementary ground target, and wherein the height measuring system is designed for taking the corresponding data record into account in the determination of the height.

6. A surveying device according to claim 1 , further comprising an electronic display-control unit for controlling the surveying device and for processing, displaying, and storing measurement data, wherein the display-control unit is situated on the support, and the detection unit is situated in an optically stable manner on the display-control unit.

7. The surveying device according to claim 1 , wherein the height measuring system is designed for carrying out a height measurement functionality, wherein:
the laser plummet emits a laser beam along the standing axis onto the ground point, and
the line sensor detects the diffuse backscattering of the laser beam from a plurality of different positions, and
the height of the surveying device above the ground is determined based on the positions of the diffuse backscattering on the line sensor in the plurality of different positions.

8. The surveying device according to claim 1 , wherein:
the detection unit comprises a slit diaphragm or a filter; or
the line sensor comprises a plurality of photosensitive elements arranged in a single row.

9. A method for measuring a height of a surveying device designed for determining the position of a target point above the ground by means of triangulation, the method comprising:
positioning a line sensor on the surveying device at a known distance from a standing axis of the surveying device;
emitting a laser beam along the standing axis onto a ground point;
detecting a diffuse backscattering of the laser beam from the ground point by means of a line sensor; and
determining the height based on a position of the diffuse backscattering on the line sensor and based on the known distance, wherein the method further comprises
projection of a linear laser marking onto the ground, with a height measuring system of a surveying device comprising a line laser unit, wherein the diffuse backscattering of the laser beam is detected by a detection unit of the height measuring system, and wherein the line sensor is designed for at least partially detecting the linear laser marking, whereby the height measuring system is designed for deriving an intensity profile based on the detected linear laser marking on the ground and, based thereon, detecting a size, a relative position, or a type of a standardized ground target located on the ground.

10. The method according to claim 9 , further comprising:
providing data records of known ground targets or supplementary ground targets, wherein the data records at least comprise data regarding a spatial extension of the particular ground target or supplementary ground target;
detecting a ground image by means of a camera; and
detecting known ground targets or supplementary ground targets in the ground image by means of image recognition,
wherein the corresponding data record is taken into account in the determination of the height.

11. The method according to claim 9 , wherein the detection of the diffuse backscattering of the laser beam takes place by the line sensor from a plurality of different positions of the line sensor, and the height is determined based on the positions of the diffuse backscattering on the line sensor in the plurality of different positions.

12. The method according to claim 9 , wherein a part of the surveying device comprising the line sensor and a line laser unit is rotated through at least 180° about the standing axis in order to determine a distance of an origin of a local coordinate system of the surveying device to a standardized ground target located on the ground, wherein:
the line laser unit projects a linear laser marking onto the ground,
the line sensor detects the diffuse backscattering of the linear laser marking with high measuring frequency from a plurality of different positions,
a plurality of intensity profiles is derived based on the detected diffuse backscatterings of the linear laser marking,
a position of the ground target is derived

Assignees

• Leica Geosystems Ag

Inventors

• Bernhard Heinz
• Hinderling Jürg
• Traber Alice

Classifications

• G01C15/105

  Optical plumbing · CPC title

• G01C15/002

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

• G01B11/002

  for measuring two or more coordinates · CPC title

• G01C5/00 Primary

  Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels (G01C3/20, G01C3/30 take precedence) · CPC title