System information

Glossary-24 Vicon MX Hardware System Reference
pose to enable the Vicon system to
determine the location of key markers on
the subject. This type of trial is required
to optimize an autolabel process in Vicon
application software. Also see Neutral
pose, Motorcycle pose, T-pose and
Dynamic trial.
Step length A temporal parameter
used in gait analysis for the distance
along the line of progression from foot
contact by one foot to foot contact by the
other foot. Also see Foot contact and Gait
analysis.
Step time A temporal parameter used
in gait analysis for the period of time, or
the percentage of the gait cycle, from
foot off to foot contact by the same foot.
Also see Foot contact, Foot off, and Gait
analysis.
Step width A temporal parameter used
in gait analysis for the distance between
the specified foot marker and the
corresponding marker on the opposite
foot when a foot contact event occurs
along the line of progression. Also see
Foot contact and Gait analysis.
Stick A visual aid to illustrate the
connection between reconstructed
marker positions or between virtual
points in a kinematic model for a subject
whose motion is being captured or
analyzed in a Vicon system. This can be
visualized as an element of the 3D
representation of the subject. Also see
Kinematic model, Marker, and Subject.
Stride length A temporal parameter
used in gait analysis for the distance
along the line of progression from one
foot contact to the next foot contact by
the same foot. Also see Foot contact, Gait
analysis, and Stride time.
Stride time A temporal parameter used
in gait analysis for the period of time, or
the percentage of the gait cycle, from
foot off to foot contact by the same foot,
that is, the time taken for the foot to do a
full gait cycle. Also see Foot contact, Foot
off, and Gait analysis.
Strobe unit A specialized piece of
illumination equipment attached to the
front of a Vicon camera. The strobe unit
generates a bright flash of light, which
illuminates the retroreflective markers
attached to the subject or object whose
motion is being captured or analyzed in a
Vicon system. The strobe unit’s flash
coincides with the time the camera’s
shutter (if present) is open. Strobe units
can be fitted with Visible Red (VR), Near
Infrared (NIR), or Infrared (IR) Light
Emitting Diodes (LEDs).
Subject 1) The target of a trial, usually
a multi-segment being such as a person
or an animal wearing Vicon markers,
whose motion is being captured or
analyzed by a Vicon system. Also see
Trial, Capture volume, and Object.
2) The 3D representation of the person,
animal, or object whose motion is being
captured or analyzed in a Vicon system.
This is a visualization of the calibrated
Vicon Skeleton (.vsk) file for a specific
subject. Individual elements of the
subject can be visualized in 3D: Bones,
Segment Axes, Marker, Stick, Bounding
box, and Parameter links.
3) A node in the hierarchy of a database
based on the generic Eclipse Node
Initialization (.eni) template file. This
equates to the Patient node in the Clinical
template and the Capture Day node in
the Animation template. Also see Eclipse
database and .eni file.
4) A collection of files named after the
trial subject. Also see .sp file, .mkr file,
and .vsk file.
Subject calibration The process by
which the Vicon application software
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