System information

Vicon MX Hardware System Reference Glossary-13
desired result, commonly the position of
the end element (or effector) in an
articulated structures. Examples are the
positioning of legs by moving the feet, or
of arms by moving the hands. This is an
inverse problem without a unique
solution. Also see Forward dynamics
(kinetics), Forward kinematics, Inverse
dynamics (kinetics), Kinematics, and
Segment.
Iris The device inside the camera lens
that controls the aperture size. Also see
Aperture.
K
Kinematic fitting The process by
which Vicon application software
positions the segments in the kinematic
model so that segments on the model fit
to the labeled trajectories. Also see
3D Workspace, Kinematic model,
Segment, Trajectory, and .vsk file.
Kinematic model A mathematical
description of a moving object. Kinematic
models for subjects or objects whose
motion is being captured or analyzed in a
Vicon system are contained in Vicon
Skeleton Template (.vst) and Vicon
Skeleton (.vsk) files. A representation of
the kinematic model for a subject can be
displayed in the 3D Workspace. Also see
Kinematics, Kinematic fitting, .vsk file,
and .vst file.
Kinematics The study of motion
without reference to its cause or its mass.
Vicon application software is concerned
with angular and linear displacements,
velocity, and acceleration. Also see
Forward kinematics and Inverse
kinematics.
Kinetics The study of the changes in
motion as a result of external factors,
including internal forces (muscle activity,
ligaments or friction in muscles and
joints) and external forces (ground or
external loads). Vicon application
software is concerned with kinetic forces,
moments (torque), and power. Also see
Force, Forward dynamics (kinetics),
Inverse dynamics (kinetics), and
Moment.
L
L-frame A type of static calibration
object. Also referred to as an ergo
calibration frame. Also see Static
calibration object and Ergo calibration
frame.
Label A name by which a point or the
trajectory of a marker is identified in
Vicon application software. The labels to
be used to identify the reconstructed
3D markers are defined in kinematic
model (.vst or .vsk file) for the subject or
in the associated marker (.mkr) file. Also
see Marker, .mkr file, Trajectory, .vsk
file, and .vst file.
LAN Local Area Network. A short-
distance data communications network—
typically within a single building or group
of buildings—used to connect computers
in order to share data and peripheral
devices (such as printers, CD-ROM
drives, and modems). Each device on a
LAN is known as a node; nodes are
connected by cables through which
messages are transmitted. Also see
Ethernet network.
LEMO® connector An electronic
connector for attaching electro-optic
devices. Connects with a push-pull self-
latching mechanism. Also see BNC
connector.
Limp index A temporal parameter used
in gait analysis for the total support
(single + double) for the current foot
divided by the total support for the
opposite foot. For a symmetric walk, the
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