Atracsys fusionTrack 500, Руководство пользователя

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User manual
Version: v4.5.2
Markers have to meet the IEC60601-1 requirement regard-
ing ‘Protection against excessive temperatures and other
hazards’.
The integrator should use redundant fiducials (i.e. four or
more fiducials instead of only three) and require the recon-
structed marker to use all of them.
The battery must be removed from the marker after use,
in order to prevent damage to the marker which may be
caused by battery leakage.
7.7 Marker geometry files
In order to be able to track a new passive custom marker , a new marker geometry file must be registered
with a name geometryxxx.ini, where xxx is (usually) the marker ID. A number higher than 100 must be used
for the ID, because smaller numbers are reserved for built-in markers . Active markers on the other side
carries their geometries with them. The fusionTrack retrieves the geometries directly after pairing.
The geometry of a marker consists of the position of each fiducial composing the marker . The SDK uses
ini files [2], supporting the basic features. The file contains the following information:
- A
[geometry]
section, containing:
– a
count
key which indicates the number of fiducials (at least 3, at most 6) composing the marker ;
– an
id
key, indicating the unique id of the geometry;
- A
[fiducialX]
section for each fiducial, where
X
goes from 0 to n
−
1 , n being the number of
fiducials composing the marker (described by the
count
key). Each
[fiducialX]
section contains
the coordinates of the fiducial (in mm, no requirement on the origin) as follows:
– an
x
key indicating the x coordinate of the position of the fiducial;
– a
y
key indicating the
y
coordinate of the position of the fiducial;
– a
z
key indicating the z coordinate of the position of the fiducial.
A user-defined file may contain comments (indicated by a ‘
;
’ as first character) or additional sections,
key-values pairs. The SDK will simply not take the additional data into account.
The used coordinate system is a Cartesian right-handed coordinate system, which origin is reported
as the marker position. All distances and positions are expressed in millimetres. In Listing 7.2 is given an
example of a geometry file for a marker with 4 fiducials , which id is 998.
1
; Example of geometry file
2
[geometry]
3
count=4
4
id=998
5
[fiducial0]
6
x=-11.819
7
y=10.993
8
z=-0.006
Atracsys / 2020-06-17 / 16:48:00
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