Web-based Learning Solutions for Communities of Practice

Visualising the Invisible in Science Centres and Science Museums
Figure 3. The general architecture of the CONNECT system.
as distributor of information giving access to large
databases, organizer of suitable didactical activities
such as conventional or virtual exhibit visits
or/and participation to live scientific experiments.
Additionally it interconnects all the members of
the network, by allowing for ubiquitous access to
educational and scientific resources to students,
teachers and users in general from all around
Europe.
The Virtual Science Thematic Park provides
support for single and multi-user (for groups as
large as a school classroom) and it includes two
major components (a) the mobile AR system
which the visitor used during his/her real visit to
a museum/science park and (b) the CONNECT
platform which facilitated the virtual visits of a
remote classroom to a museum/science park.
The Mobile AR System
The mobile AR system (figure 4) was designed to
provide 3D graphics superimposed on the user’s
field of vision together with other multimedia
information. Thus, it allowed to “extend” a real
exhibit with virtual objects. This is regarded as
a particularly powerful tool for visualizing complex
concepts in physics that are fundamental
yet imperceptible (such as electric or magnetic
fields, forces, etc). Furthermore, it allowed for
remote classes to interact, either on-line or offline,
with a visit to a science museum/park. The
mobile AR system consisted of several hardware
devices, including: a wearable processing unit
(heart of the system), personal display units (optical
see-through glasses) to project/embed virtual
3-D objects onto the real exhibit environment,
tracking sensors to determine the visitors’ exact
location and orientation (six degrees of freedom),
video cameras for recording the students’ learning
activities and the exhibit augmentation, human
interface devices (microphone and headphones
for real-time interaction with the exhibit and the
remote classroom) and the transmission module
to the mainframe computer in order to stream the
augmented view to the CONNECT platform.
Furthermore, the mobile AR system was supported
by a multiplicity of software tools, such as
recognition (tracing and identification) of individu-
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