Surveying system and auxiliary measuring instrument

Patent metadata

Field	Value
Publication number	US-12025467-B2
Application number	US-202117526989-A
Country	US
Kind code	B2
Filing date	Nov 15, 2021
Priority date	Oct 31, 2018
Publication date	Jul 2, 2024
Grant date	Jul 2, 2024

Abstract

A calibrating method and system for an auxiliary measuring instrument which is designed to form together with a ground-based, stationary, surveying device having range-and-direction measuring functionality, a total station, a system for surveying and/or staking out object points. The auxiliary measuring instrument including a body which has a code for determining the orientation by using a pivoting movement of the body about a resting contact end of the auxiliary measuring instrument.

First claim

What is claimed is:

1. A calibrating method for an auxiliary measuring instrument which is designed to form together with a ground-based, stationary, surveying device having range-and-direction measuring functionality, a total station, a system for surveying and/or staking out object points,
the auxiliary measuring instrument having an elongate main body designed for manual handling, so that an object point can be contacted by a user with a contact end of the auxiliary measuring instrument,
the auxiliary measuring instrument having a body, in particular a sphere, at a further end of the main body at a fixed distance from the contact end, in particular with the centre of the body arranged on the longitudinal axis of the main body,
the body having on its surface an optical 2D code, which is designed in such a way that an orientation, a position, of the body, and consequently of the auxiliary measuring instrument, can be determined by image processing of a camera image of at least part of the 2D code on the basis of stored decoding information,
the method comprising:
contacting an object point with the contact end,
pivoting the auxiliary measuring instrument about the resting contact end, resulting in a movement of the body which, because of the resting contact end and the fixed distance from the contact end, is subject to such a defined constraint,
during which, optical capturing by means of camera images of at least part of the body, and consequently of the 2D code, so that various pivoting locations of the body are captured,
image-processing evaluation of the captured 2D code in at least some of the camera images in which at least two of the various pivoting locations of the body are depicted, for ascertaining the respective orientation of the body on the basis of the 2D code,
determining at least two vectors, associated with the at least two pivoting locations, from a reference point, in particular a midpoint, of the body to the contact end on the basis of the said constraint of the body movement from the respective ascertained orientation of the body,
calibrating the stored decoding information on the basis of the at least two vectors.

2. The method according to claim 1 , wherein the decoding information comprises rotation matrices in relation to at least two turning angles, in particular pitching and rolling angles.

3. The method according to claim 1 , wherein deviations of code markings from a desired or ideal position on the body and/or of at least one dimension of the auxiliary measuring instrument, in particular its length, from a desired or ideal dimension are compensated by the calibration.

4. The method according to claim 1 , wherein the 2D code is designed in such a way that an orientation and range of the body, and based on this the location of the auxiliary measuring instrument, can be completely determined by image evaluation of a camera image of the 2D code and on the basis of the stored decoding information.

5. The method according to claim 1 , wherein the auxiliary measuring instrument has a position and/or orientation sensor, and, as part of the method, a calibration of the position and/or orientation sensor takes place on the basis of the constraint by using the captured 2D code.

6. The method according to claim 1 , wherein at least in relation to one of the various pivoting locations, a range from the auxiliary measuring instrument, in particular directly from the body, that is linked or can be linked with the location of a camera capturing the camera images is measured and used in the calibration.

7. The method according to claim 1 , wherein the length of the auxiliary measuring instrument is corrected or determined on the basis of at least some of the camera images recorded during the pivoting movement, in particular as the distance from a reference point, in particular the midpoint of the body, of the auxiliary measuring instrument to the contact end.

8. A ground-based surveying system for surveying and/or staking out object points, with a stationary surveying device having range-and-direction measuring functionality, a total station, and an auxiliary measuring instrument,
the system comprising a camera,
the auxiliary measuring instrument comprising:
an elongate main body, designed for manual handling, so that an object point can be contacted by a user with a contact end of the auxiliary measuring instrument,
at a further end of the main body, at a fixed distance from the contact end, a body, a sphere with the centre of the body arranged on the longitudinal axis of the main body, and the body having on its surface an optical 2D code, which is designed in such a way that an orientation and also a position, of the body, and consequently of the auxiliary measuring instrument, can be determined by image processing of a camera image of at least part of the 2D code on the basis of stored decoding information, and
the surveying system having calibrating functionality, when performing which:
camera images in which at least two different pivoting locations of the body are captured are recorded by the camera, the locations being provided by pivoting the auxiliary measuring instrument about the resting contact end, resulting in a movement of the body which, because of the resting contact end and the fixed distance from the contact end, is subject to such a defined constraint, and
by means of image processing, the 2D code captured in the camera images is evaluated for ascertaining the respective orientation of the body on the basis of the 2D code,
on the basis of the said constraint of the body movement, at least two vectors,
associated with the at least two pivoting locations, from a reference point which is a midpoint, of the body to the contact end are determined from the respective ascertained orientation,
a calibration of the stored decoding information takes place on the basis of the at least two vectors.

9. The surveying system according to claim 8 , wherein the surveying system has automatic state monitoring, which, dependent on the state of the surveying system, suggests a performance of the calibrating functionality to a user.

10. The surveying system according to claim 8 , wherein as part of the calibrating functionality, any deformation of the auxiliary measuring instrument of its longitudinal axis, is established, quantified and/or compensated.

11. The surveying system according to claim 8 , wherein the length of the auxiliary measuring instrument is variable in a defined way:
by the main body having a holder for receiving pole-shaped extension pieces, and/or
by the main body being telescopically designed, so that its length is variable steplessly,
and, when performing the calibrating functionality, the current length of the auxiliary measuring instrument is verified or ascertained.

12. The surveying system according to claim 8 , wherein the surveying device has a drive for automatically changing a target direction and target-tracking functionality, so that, as part of the calibrating functionality, the target direction automatically follows the moving body.

13. The surveying system according to claim 8 , wherein the surveying system is designed in such a way that, as part of the calibrating functionality, an instruction with respect to pivoting the auxiliary measuring instrument for generating the various pivoting locations of the body is displayed to a user on a display with regard to optimum arrangement of the pivoting locations.

14. The surveying system according to claim 8 , wherein as part of the calibrating functionality, an automatic ending of the capturing of pivoting locations of the

Assignees

• Leica Geosystems Ag

Inventors

• MüLLER JOSEF
• Scheja Jochen
• Faix Oliver
• Bösch Thomas
• Iseli Claudio

Classifications

• G01C15/06

  Surveyors' staffs; Movable markers · CPC title

• G06T7/70

  Determining position or orientation of objects or cameras (camera calibration G06T7/80) · CPC title

• G06T7/80

  Analysis of captured images to determine intrinsic or extrinsic camera parameters, i.e. camera calibration · CPC title

• G01C15/002

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

• G01C25/00 Primary

  Manufacturing, calibrating, cleaning, or repairing instruments or devices referred to in the other groups of this subclass (testing, calibrating or compensating compasses G01C17/38) · CPC title