Measuring system and measuring method

Patent metadata

Field	Value
Publication number	US-10648792-B2
Application number	US-201715713787-A
Country	US
Kind code	B2
Filing date	Sep 25, 2017
Priority date	Sep 30, 2016
Publication date	May 12, 2020
Grant date	May 12, 2020

Abstract

A measuring system having a measuring tool which includes a probe body and an optical marker, a camera for recording image data of the measuring tool, and an evaluation and control unit which is configured to evaluate the image data recorded by the camera and use the data to determine spatial position coordinates of the optical marker. The evaluation and control unit is also configured to calculate the deformation of the measuring tool due to external mechanical loading acting on the measuring tool, and to determine spatial position coordinates of the probe body based on the spatial position coordinates of the optical marker and the calculated deformation.

First claim

What is claimed is:

1. Measuring system comprising:
a measuring tool that comprises a probe body and an optical marker;
a camera for recording image data of the measuring tool; and
an evaluation and control unit that is configured to evaluate the image data captured by the camera and to determine spatial position coordinates of the optical marker based on the image data,
wherein:
the evaluation and control unit is configured to calculate a deformation of the measuring tool due to external mechanical loading acting on the measuring tool, and to determine spatial position coordinates of the probe body based on the spatial position coordinates of the optical marker and the calculated deformation,
the evaluation and control unit is configured to calculate the deformation of the measuring tool based on a mechanical substitute model, in which the measuring tool is modelled as a mechanical system that comprises at least two rigid bodies and a first elastic node that connects the two rigid bodies to one another,
the deformation is modelled in the mechanical substitute model as a translation and/or rotation of the two rigid bodies in relation to one another and is calculated using the following equation:
{right arrow over (u)}=N*{right arrow over (b)},
where {right arrow over (u)} is a deformation vector which describes the deformation of the measuring tool in vector notation,
where {right arrow over (b)} describes the external mechanical loading in vector notation,
where N is a compliance matrix that describes compliance properties of the first elastic node as a result of the external mechanical loading, and

the spatial position coordinates of the probe body are calculated uisng the following equation:

p
→

=

p
→

s

+

M
s

*

(

p

N
⁢

⁢
1

→

+

f
⁡

(

u
→

,

t

N
⁢

⁢
1

→

)

)

with
⁢

⁢

u
→

=

(

v

0
⁢

⁢
x

v

0
⁢

⁢
y

v

0
⁢

⁢
z

δ
rx

δ
ry

δ
rz

)

,

⁢
where

f
⁡

(

u
→

,

t

N
⁢

⁢
1

→

)

=

R
z

⁡

(

δ
rz

)

*

R
y

⁡

(

δ

Assignees

• Zeiss Carl Industrielle Messtechnik Gmbh

Inventors

• Held Tobias

Classifications

• G06T2207/30204

  Marker · CPC title

• G01B5/008 Primary

  using coordinate measuring machines · CPC title

• G06T7/73

  using feature-based methods · CPC title

• G01B11/002

  for measuring two or more coordinates · CPC title

• G01B11/007 Primary

  feeler heads therefor · CPC title