Art ARTTRACK Installation Manual page 24

3 Introduction to tracking
Note: In pure optical tracking systems tracking is only possible as long as
objects or individuals to be tracked are equipped with single markers or targets
the target is not occluded by any other objects in the cameras' line of sight, which
could even be the object itself
the target is positioned inside the tracking range of the cameras
at least four markers of a target are visible to at least two cameras (this step enables
tracking).
Figure 3.1: Concept of optical tracking (stereo vision)
The SMARTTRACK2/3/M
signed to be used in small volumes. Please refer to 4.3.1 on page 31 for
more information on the tracking volume of the
Marker types Passive markers are covered with retro reflective material - they act as
light reflectors. Active light emitters (i.e. based on infrared LEDs) are called active mark-
ers (see chapter 5.7 on page 75).
Hybrid tracking In addition to tracking by a pure optical system it is possible to uti-
lize data from inertial measurement units (IMU). These devices usually consist of several
components such as gyroscopes, accelerometers and magnetometers. The underlying
principle is the combination of solid-state microelectromechanical systems with integrated
circuits and analog or digital outputs to achieve 6DOF rotational information.
Some of the most important advantages of hybrid tracking are:
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have a limited field-of-view and range! It is de-
SMARTTRACK2/3/M .