Automotive User Interfaces and Interactive Vehicular Applications

visibility of available information channels. The Target
button toggles a ‘target marker’ on the map which is used
to specify a location for which nearby items are displayed.
The marker can be moved anywhere on the map, allowing
the user to re-query previews. The Marker/Link buttons
allow the user to choose between the three information link
modes – Google style markers, coloured markers and
transparent arrows - that associate the preview with
locations on the map.
IN-CAR FIELD STUDY
The aim of the study was to evaluate the use of the
SafeTRIP Info Explorer in a naturalistic context in
performing information search efficiently and effectively –
with a view to assist the driver in finding certain services.
The participants would meet two experimenters in the car
park. The car was equipped with an in-car navigation
application that was used to simply display the map and
current location during the study.
One experimenter was the driver and the other acted as the
passenger in the back seat. All three car occupants created
a ‘virtual friendship’ on a road trip. The experimenter
drove the car around the city for two hours. The
participant was encouraged to think-aloud throughout the
session focusing on discussions about the information
exploration and UI. The session ended with a brief
questionnaire.
Figure 6 - Participant using Tablet in the Car
16 participants (11 males and 5 females) aged between 19
and 46 were recruited through adverts on notice boards
and mailing lists. Half of the participants owned a touchenabled
smartphone, the other half had tried one. Four of
the participants owned a tablet device, and all but one
participant had tried one before.
PRELIMINARY RESULTS AND DISCUSSION
12 participants used the map in the application to locate
themselves, find location of places, estimate travel
distances and assist the driver in terms of navigation. The
rest focused on the information itself, leaving navigation
entirely to the driver.
All participants familiarized themselves very quickly with
the information layout and tools – commenting that the
preview items and the links to the map supported quick
comparison of results, allowing them to make a selection –
this was in spite of the layout being very different to a
traditional search listing that they are familiar with. In
addition, all participants reported that the linking strategy
of coloured marker and transparent link was better
compared to traditional Google-type markers.
During the trial, some participants experienced issues with
the positioning as the tablet used the inbuilt GPS sensor. It
would be preferable for the application to use the car’s
positioning system which seem to work better under
similar conditions. The next version of SafeTRIP Info
Explorer will use this approach.
Structured information with short phrases (used for petrol
station channel) as rich description was preferred over text
description (used in hotel channel) – even if the later had
more useful information. The majority of participants
reported discomfort when reading text for a long time in
the moving vehicle.
CONCLUSION
Smartphones have already invaded the vehicle; it is only a
matter of time before tablets do. However, tablets are much
more versatile and can bring a number of benefits to the
occupants. As shown by this study, application developers
targeting these devices should account for their potential
in-car use. The UI design and interaction paradigms
should lend themselves well to in-vehicle usage – such as
the FMI approach for searching, exploring and
visualization rich data, the Target for redirecting searches
and linking strategies to minimize cognitive load to
associate rich previews with map locations. The
application itself should allow for personalization (e.g.
choice of map provider) and be able to interact with other
in-car systems (e.g. for positioning and communication) as
well as other applications (e.g. pushing a new destination
to the in-car navigation application from the tablet).
ACKNOWLEDGMENTS
The authors of this paper would like to thank the partners
within the SafeTRIP consortium. They are in particular
thankful to the FP7 and the European Commission for
funding the SafeTRIP project.
REFERENCES
1. Beeharee, A.K., Laqua, S., and Sasse, M.A. (2011)
Navigating Haystacks at 70mph: Intelligent Search for
Intelligent In-Car Services. In Multimodal Interfaces
forAutomotive Applications workshop at Intelligent
User Interfaces(IUI) 2011.
2. Beeharee, A.K., Niemann, B., Titomanlio, S. & Grau
Panea, G. (2011) SafeTRIP – A Green Architecture for
an Open ITS. ITS Europe Congress Lyon 2011.
3. Laqua, S. and Brna, P. (2005) The Focus-Metaphor
Approach: A Novel Concept for the Design of Adaptive
and User-Centric Interfaces. In Proc. Interact 2005,
Springer (2005), 295-308.