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this work is based on the navigation approach and
resulting software from the work by (Heiniz et al.,
2012). We extend and simplify the existing approach
for graph creation. Sequential views from the initial
implementation are extended by the wizard metaphor
(Tidwell, 2010). This technique guides users through
the creation of the graph by locking the user into a
sequence of several well-defined views. Therefore,
graph creation is done step-by-step in a logical order.
This way we are able to lower user’s cognition load
and avoid misleading handling of the tool.
Furthermore, an additional view is introduced
which is based on the floor plan of the building. This
view adapts well to the touch interface of the applica-
tion and allows a more natural handling of the graph.
During the editing, users have an overview over the
created graph and may update and delete data ele-
ments more easily. In case of missing floor plan for a
building, the proposed procedure switches into a de-
fault setting, where the user places elements of the
building graph on a white canvas. This option allows
a touch-based visual handling in a symbolic space.
Additionally, the application for indoor navigation
introduced in (Heiniz et al., 2012) is extended with
the presented approach. Users often want a more con-
ventional overview of the route while navigating with
the application. Therefore, they are able to switch
from the initial step-by-step view to an overview of
the building to observe the passed steps and the route
ahead. This way we introduce an additional view that
supports users which experience difficulties with pure
sequential instructions. Using this enhancement, we
were able to combine the advantages of landmark-
based indoor navigation (e.g., best-effort positioning
and navigation approach based on human cognition)
and the more common information from a building
floor plan.
3 RELATED WORK
The following approaches base on the idea of support-
ing positioning through the data structure. Thus, the
system is more independent from the existing techni-
cal infrastructure in the building.
Landmark-based indoor navigation (Heiniz et al.,
2012) does not rely on additional sensors in the build-
ing or the navigation device to lead the user to his des-
tination point in a building. This approach includes
the user into the navigation task by letting him sub-
consciously collect visual impressions about his sur-
roundings. The user has to perceive his surroundings
and compare certain areas of the building to presented
depictions in the application. He then actively in-
forms the system about his position in the building by
selecting certain areas from a list of preselected posi-
tions. Using physical constrains of the building and
the human power of observation, it was possible to
design a reliable navigation system. Landmark-based
indoor navigation serves as the starting point to this
work.
The navigation approach presented by (Chowaw-
Liebman et al., 2010) provides an advanced data
model for buildings. Users follow generated textual
instructions and thus are guided through the graph
structure of the data model. The position of the user is
monitoredvia the devicewhispering approach (Krem-
pels et al., 2011) during the navigation.
(Baras et al., 2010) presented an approach that
leads users through a building without any hardware-
based positioning. In this work, a model of the tar-
get building provides the route based on area iden-
tifiers such as room names or special locations. Ob-
jects which base on these identifiers are logically con-
nected. Users are following the sequence of locations
and reach their destination. However, the presented
system provides very sparse information which lacks
details. Furthermore, all information is presented as
text, therefore, users need to be familiar with the
building to follow the route.
Another approach working with imprecise posi-
tioning was introduced by (Jensen et al., 2009). The
presented system encloses areas to logical objects
which are connected in a building graph. Human
movement is tracked by a technique based on RFID
signal recognition. Even though this positioning ap-
proach shares the drawbacks of all hardware-based
positioning solutions, the graph on its own provides
strong constrains for possible actions within the build-
ing and thus the introduced navigation approach is
still reliable. A proper building structure enables
flawless navigation for this approach.
Apparently, it is possible to navigate a person
through a building without precise hardware-based
positioning. A proper underlying data structure is cru-
cial to achieve a reliable indoor navigation approach.
However, most of the introduced approaches still use
floor plans to depict user location even though this po-
sition lacks precise coordinates. We will use this find-
ing to evaluate human mapping of points on a map to
areas in the building.
Usability aspects play an important role for de-
sign of the building graph construction tool. We re-
course to a certain set of design principles and de-
sign patterns to create an accessible and user-friendly
experience. To optimize the existing graph creation
views, we adapted design patterns from (Shneider-
man, 2003). Additionally, we implemented the wiz-
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