System information

Vicon MX Hardware System Reference Glossary-25
creates or modifies a kinematic model for
a specific subject.
During this processing, the Vicon
application software compares the
physical segments, joints, and markers
on the trial subject to either a) the
definition of segments, joints, and
markers in the generic model for the
subject type described in the associated
Vicon Skeleton Template (.vst) file in
Vicon iQ or b) marker locations in a
previously manually labeled trial for that
subject in Workstation.
The results of subject calibration are
stored in a subject-specific Vicon
Skeleton (.vsk) file, which is used to
automatically track and label segments
and marker trajectories for the subject in
in the 3D Workspace. Also see Autolabel
calibration, Kinematic model, Marker,
Segment, Trajectory, .vsk file, and .vst
file.
SV Cam A small format, wide-angle
lens CMOS digital sensor camera used in
a Vicon V-series system. This type of
camera is the same specification as a
VCam camera, but with a reduced strobe
size. Also see CMOS and VCam.
Synchronization The process by which
a signal change common to all camera
view and analog signals is used to match
them in time. This causes analog and/or
video data from different sources to
match exactly. Also see Analog,
Datastation, and MX Control.
System calibration See Camera
calibration.
.system file An XML file with extension
.system, which contains configuration
settings for Vicon system hardware
managed by Nexus application software.
This file is created in the System browser
pane in Nexus. Also see Nexus.
T
T-pose A form of the neutral pose used
when capturing a static trial in
Workstation or starting a RoM trial in
Vicon iQ and Nexus application software.
In this pose, the subject stands in the
basic neutral pose and raises the arms
out straight to the sides with palms facing
down (in a position in the shape of a T).
This type of static trial may be required
for the autolabel or the subject calibration
process. Also see Autolabel calibration,
Neutral pose, Motorcycle pose, RoM trial,
Static trial, and Subject calibration.
Tail An inaccurate reconstruction for a
marker trajectory that occurs
immediately before and after gaps. Tails
can occur when a marker is partially
occluded (or blocked) from the camera’s
view during motion capture, thus
resulting in unreliable data for that
marker during that period of time. Tails
can be eliminated using editing tools in
Vicon application software. Also see Gap.
Tarsus See RealTime Engine (RTE).
Threshold grid In Vicon MX, a grid
superimposed over the image displayed
in a camera view pane in which raw, 2D
camera data can be manually marked to
be used for processing or to be discarded.
This enables grayscale blobs generated
from unwanted light sources such as
stray reflections from other objects or
surfaces in the capture volume and
opposing strobe units to be ignored. You
can have Vicon application software
automatically create threshold grids, or
you can create them yourself. The
equivalent functionality for Vicon V-series
systems is provided by camera masks.
Also see Camera mask, Capture volume,
Grayscale blob, and .vtt file.
Tilt The rotation of a stationary camera
in a vertical plane about a horizontal axis
MXhardware_Reference.book Page 25 Thursday, September 7, 2006 11:36 AM