Laser scanner

Patent metadata

Field	Value
Publication number	US-12339368-B2
Application number	US-202318201670-A
Country	US
Kind code	B2
Filing date	May 24, 2023
Priority date	Nov 10, 2016
Publication date	Jun 24, 2025
Grant date	Jun 24, 2025

Abstract

A laser scanner and a system with a laser scanner for measuring an environment. The laser scanner includes an optical distance measuring device, a support, a beam steering unit rotatably fixed to the support which rotates around a beam axis of rotation. The beam steering unit includes a mirrored surface which deflects radiation used in the optical distance measurement and an angle encoder for recording angle data. The optical distance measurement is performed by a progressive rotation of the beam steering unit about the beam axis of rotation and the continuous emission of a distance measurement radiation, the emission being made through an outlet area arranged in the direction of the mirrored surface on the support, the receiving optics for receiving radiation are arranged on the support, and wherein the outlet area has a lateral offset with respect to the optical axis of the receiving optics.

First claim

The invention claimed is:

1. A laser scanner for optical measurement of an environment, comprising
an optical distance measuring device for detecting distance measurement data, having
a transmitter unit for emitting a distance measurement radiation and
a receiver unit for receiving returning parts of the distance measurement radiation,

a support,
a beam steering unit for the distance measurement radiation, which is rotationally fixed to the support about a beam axis of rotation, in particular a fast axis of rotation, and
an angle encoder for recording angle data with respect to a rotation of the beam steering unit about the beam axis of rotation,
characterized in that
the beam steering unit is connected to a shaft mounted in the support along the beam axis of rotation, in particular wherein the shaft penetrates into the beam steering unit with a defined penetration depth or is designed integrally with the beam steering unit,
a bell-shaped element is arranged on the shaft, in particular wherein the bell-shaped element is arranged in a fixed position on the shaft or is formed integrally with the shaft, wherein the bell-shaped element defines a bell-shaped body and a bell-shaped back,
passive magnetic elements of a drive are arranged in the bell-shaped body for rotating the shaft,
active drive elements of the drive are arranged anchored in the support for generating an electromagnetic interaction with the passive magnetic elements, in particular electrical coil elements, wherein the active drive elements at least partially protrude into the bell-shaped body, and
by means of a radial interaction between the active drive elements and the passive magnetic elements the shaft and therefore the beam steering unit undergo a defined rotational motion around the beam axis of rotation.

2. The laser scanner as claimed in claim 1 , wherein the active drive elements are fully recessed into the bell-shaped body.

3. The laser scanner as claimed in claim 1 , wherein at least one rim of the bearing for mounting the shaft in the support protrudes into the bell-shaped body.

4. The laser scanner as claimed in claim 3 , wherein the rim of the bearing protruding into the bell-shaped body is designed as a roller bearing rim and roller bodies of the roller bearing rim protrude at least partially into the bell-shaped body.

5. The laser scanner as claimed in claim 1 , wherein at least one rim of the bearing for mounting the shaft in the support protrudes into the beam steering unit, in particular wherein the rim protruding into the beam steering unit is designed as a roller bearing rim and roller bodies of the roller bearing rim protrude at least partially into the beam steering unit.

6. The laser scanner as claimed in claim 1 , wherein the shaft comprises only a single effective stabilization region axially along the beam axis of rotation, which is used to stabilize the shaft against a tilting of the shaft relative to the support, wherein the beam steering unit, the bell-shaped element and the shaft are designed and arranged with respect to each other in such a way that their common center of gravity axially along the beam axis of rotation is located in the stabilization region, in particular wherein the stabilization is achieved exclusively by a bearing which substantially axially-symmetrically surrounds the center of gravity for mounting the shaft in the support.

7. The laser scanner as claimed in claim 1 , wherein on the back of the bell-shaped element a coding element for the angle encoder is arranged, in particular wherein the coding element is designed integrally with the bell-shaped element.

8. The laser scanner as claimed in claim 1 , wherein at least one of the following connections is made exclusively by means of a bonding and/or compression
a connection of the shaft to the stabilization element,
a connection of the shaft to the bell-shaped element,
a connection of the passive magnetic element to the bell-shaped element, and
a connection of the coding element to the bell-shaped element.

9. The laser scanner as claimed in claim 1 , wherein the laser scanner is configured such that the distance measurement data and the angle data, hereafter designated as measurement data, are recorded as part of a measurement process, which comprises a scanning sensing by means of the distance measuring device with
a defined continuous rotation of the beam steering unit about the beam axis of rotation, and
a continuous emission of the distance measurement radiation and a continuous reception of returning parts of the distance measurement radiation.

10. The laser scanner according to claim 9 , wherein
the support is fixed on a base of the laser scanner in a manner rotationally about a support axis of rotation, in particular a slow axis of rotation,
the laser scanner comprises a further angle encoder for recording further angle data with respect to a rotation of the support about the support axis of rotation, and
the laser scanner is configured such that the scanning sensing of the measurement process further comprises a defined continuous rotation of the support about the support axis of rotation, and that the further angle data, forming part the measurement data, is also recorded in the course of the measurement process.

11. The laser scanner according to claim 10 , wherein during the measurement process the beam steering unit rotates about the beam axis of rotation with a rotation speed of at least 50 Hz, in particular of at least 100 Hz, and/or
during the measurement process the base rotates about the support axis of rotation with a rotation speed of at least 0.01 Hz, in particular of at least 0.02 Hz.

12. The laser scanner as claimed in claim 1 , wherein the beam steering unit is axially mounted in the support along the beam axis of rotation via the shaft, wherein
the beam steering unit comprises a mirrored surface for a deflection of the distance measurement radiation, in particular a plane mirrored surface which is tilted by 45° with respect to the beam axis of rotation, or a tilted parabolic mirrored surface,
the shaft has a penetration region at one end,
the beam steering unit has an enclosure region for enclosing the penetration region of the shaft during a coupling of the beam steering unit to the shaft,
the enclosure region has a shape which is suitable for enclosing the shaft over a length of the penetration region during the coupling in such a way that in the coupled condition a gap with a defined width exists between the shaft and the enclosure region of the beam steering unit,
the enclosure region comprises a stabilization element that can be pressed in the gap for tolerance compensation and for the stable connection of the beam steering unit to the shaft,
in an uncoupled condition the stabilization element has a thickness which is greater than the width of the gap, and
the beam steering unit, in particular the enclosure region, the shaft and the stabilization element are designed in such a way and interact in such a way that during the coupling of the beam steering unit to the shaft the stabilization element arranged between the enclosure region and the shaft is pressed into the gap, and in the coupled condition is present in the gap in such a deformed state, in particular wherein at least a portion of the stabilization element is plastically deformed, that defined residual elastic forces radially to the beam axis of rotation act on the beam steering unit and the shaft, that
the beam steering unit and the shaft are stabilized in relation to each other in the axial direction with respect to the beam axis of rotation,
the beam steering unit is stabilized against a ti

Assignees

• Leica Geosystems Ag

Inventors

• Mark Simon
• Bereuter Klaus
• Müller Benjamin
• Steffen Roman
• Böckem Burkhard
• Dold Jürgen
• Scheja Jochen
• Heinzle Lukas
• Dumoulin Charles Leopold Elisabeth

Classifications

• G01S7/4814

  of transmitters alone · CPC title

• G01S7/4811

  common to transmitter and receiver · CPC title

• G01B11/024

  by means of diode-array scanning · CPC title

• G06T2207/10028

  Range image; Depth image; 3D point clouds · CPC title

• G06T11/00

  Two-dimensional [2D] image generation · CPC title