Development of an Augmented Reality system using ARToolKit

Development of an Augmented Reality system using ARToolKit and user invisible markers
beneath it. Two types of lenses are available; volumetric and flat lenses. Fundamental
tasks that can be carried out using either of those lenses are magnification, information
filtering and object selection and manipulation. In Figure 2.14 and Figure 2.15 are
shown the application of volumetric and flat lenses for magnifying a certain area within
an AR environment. Figure 2.13 shows the initial virtual scene.
Figure 2.13 A virtual scene Figure 2.14 Volumetric lens Figure 2.15 Flat lens application
application
2.2.2.4 Hand-held video projectors
In [Ras03] is described an AR system that uses hand-held projectors for the
augmentation of objects. Object recognition is done through fiducials that are attached
to objects of interest. They do not only provide object identity, but are also used to
determine the position and orientation of the camera. Since the system is fully calibrated
this information can be related to the position and orientation of the projector. In this
way content can be overlaid on an object as required. Figure 2.16 shows the use of a
hand-held video projector for guiding a user through an environment containing storage
bins.
2.2.3 Spatial displays
Figure 2.16 AR using a hand-held video
projector
The two before described main categories of display devices take a body-attached
approach. Also the possibility exists to detach technology from the user, and have most
of it integrated in the environment. This is the way spatial displays try to offer
possibilities for AR. The augmentation of the environment can be done in three ways;
using video see-through, optical see-through or direct augmentation. Depending on
which is used a different kind of spatial display is created.
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