New Augmented Reality Applications - Teaching through Multi-User Virtual Environments - page 370

AR has been around for more than a decade.
However, only a few systems have been applied
to education. Project MagicBook was presented at
the SIGGRAPH conference in 2000 (Billinghurst,
Kato, & Poupyrev, 2001). A MagicBook includes
text and images like any other book. But it also
uses special markers that can be viewed with an
HMD that superimposes 3D animated scenes on
the topic's pages. This interesting approach is
considered to be the first application of AR to
education. It was followed by the implementation
of ARToolkit , an open-source AR library widely
used for writing AR applications.
Project MARIE was presented in 2002 (Liaro-
kapis et al., 2002). It supports multiple students
interacting with various virtual objects. It also
provides a framework for writing AR-based
educational applications. For example, it has been
used to browse Web3D worlds for engineering
education (Liarokapis et al., 2004).
Researchers at the Technical University of
Vienna started working on AR-based education
with the StudierStube project. More recently,
they built another system called Construct3D
(Kaufmann, Schmalstieg, & Wagner, 2000).
Construct3D has been successfully applied to
geometry and mathematics teaching (Kaufmann
& Schmalstieg, 2002).
All of the above applications are based on
AR technology that is either too expensive or too
complex for every-day use. With the advent of
ARToolkit and Personal Data Assistants (PDAs)
AR systems became smaller and less expensive.
Such systems are not immersive, but they are
better suited for education applications where
the students may be young and a bit careless.
The “Education Arcade” group of MIT has col-
laborated with the Boston Museum of Sciences
to develop the project “Mystery at the Museum”
(Klopfer et al., 2005). In the project a child and
an adult are paired up. They are given a PDA
with a camera and then they are asked to solve an
enigma by looking for clues in the Museum. The
clues are markers and the enigma is related to a

relevant historic event. The children involved in
the project enjoyed the experience and learned a
lot of history. Our idea is somehow similar.

Ambiguity and 3D Perception

Not every student has the same 3D spatial percep-
tion. Some students have difficulties envisioning
3D objects drawn or displayed in 2D. This is rel-
evant in Chemistry where students must analyze
3D structures in order to devise correct answers
to the class problems.
2D produces optical illusions that usually stem
from the ambiguities of 2D rendering. Some ex-
amples of these illusions are the Necker cube, the
Schroder stairs, or some of M.C. Escher drawings.
Figure 3 shows the Necker cube and Schroder's
stair ambiguities. The Necker cube drawing is
ambiguous because the image does not tell which
face of the cube is in the back and which in the
front, producing two different interpretations of
the drawing. In the Schroder stairs, the illusion
of a change of perspective shows up when the
drawing is rotated 90º clockwise or when the head
is turned to the left. Finally, M.C. Escher became
famous for his representations of paradoxes and
ambiguities. For example, in his “Waterfall”
lithography of 1961 the water is always flowing
thanks to an optical illusion.

AUgmeNTeD ReALITY AND
INORgANIC CHemISTRY
eDUCATION

Brief Description of the
Classes Where AR is Used

We use AR to help teach three different classes
related to Inorganic Chemistry: Material Sciences,
Ceramic Inorganic Chemistry and Advanced
Chemistry Laboratory. The classes belong to the
Chemistry program of the Universitat Jaume I of
Castellón in Spain.