Http:// 1 A Framework for Mobile, Context-Aware Trails-based Applications: Experiences with an Applications-led Approach Cormac Driver

http://www.dsg.cs.tcd.ie1

A Framework for Mobile, Context-Aware Trails-based Applications: Experiences with an Applications-led

Approach

Cormac Driver Eamonn Linehan Siobhán Clarke

What makes for good applications-led research in ubiquitous computing?Workshop 1, Pervasive 2005

May 11th 2005


Overview

• Hermes Project & Trails Metaphor

• Framework Development

• The ‘Oisín goes to Trinity’ Application

• Issues, Experiences and Suggested Remedies


Hermes Project• Project Goal

To design and implement a software framework to facilitate developers in building mobile, context-aware applications.

• Why are we doing this?

Common application development issues recur over separate application development efforts:

– Context acquisition and understanding– Context-based application adaptation– Intermittent network connectivity– Intuitively representating the user’s environment– Impact on social environment

• Privacy, perceptual pervasive observation, HCI, CSCW– Device characteristics

• Form factor, capabilities• Devices users interact with, embedded devices

• Trails Metaphor

We consider trails applications to be archetypal ubiquitous computing applications.


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Framework Development• Framework Development Methodology

We are building a set of mobile, context-aware trails-based applications, extracting the commonality and packaging it in a generic manner in a software framework.

Using the ‘3 Examples’ approach proposed by Roberts and Johnson [1].

Diverse set of trails-based applications being considered:– Courier Support System– Campus Guide– Treasure Hunt Game– Basic Route Planner– Hill Walking Assistant


• The First Protoype

‘Oisín goes to Trinity’ is a mobile, context-aware trails-based application that allows users to follow trails around the Trinity College Dublin campus.

Runs on a Sharp Zaurus PDA and was built using J2ME.

It is the first application in a series being developed in order to build the Hermes framework.

Application 1: ‘Oisín goes to Trinity’


‘Oisín goes to Trinity’

Issues, Experiences &

Suggested Remedies


Issue #1: Lack of Interdisciplinary Expertise

• Lack of Psychology Expertise

Questionnaire designed by computer scientists.

e.g., “What do you think the Oisín application should not allow you to do?”

• Lack of Graphical User Interface Expertise

Prevented the collection of data on application features we are interested in.

e.g., dynamic trail reconfiguration not observed by users.


Remedy #1: Collaboration with experts

• Cooperation with Experts in Psychometrics

Development of a standardised questionnaire for measuring user-perceived quality of mobile context-aware applications.

• Collaboration with Graphical User Interface Experts

Ease of use of the application’s interface can colour the results of questionnaires as described by Klein [2].

Experts in the field of human-computer interaction should be consulted.

e.g., we conducted a user interface review.


Issue #2: Social Computing• Hardware Form Factor

Oisín goes to Trinity runs on a sharp Zaurus PDA which has a GPS device connected via cable.

• Social Acceptance of the Devices

Unwanted attention can be attracted from passers-by.


Remedy #2: Social Computing• Hardware Form Factor & Social Acceptance

Factors identified by MIT Media Lab [3] have an impact on social computing:

– Familiarity

– Appeal

– Disruption

– Pervasiveness

Future applications to be designed for mobile phones.


Issue #3: Implementation• Location System

Limited resolution and unpredictable error of our chosen location system – GPS.

• Mobile Device Limitations

Execution of reconfiguration algorithms on resource constrained mobile devices was inefficient due to the approach taken.

e.g., a brute force approach took approximately 30 seconds to evaluate a 5 activity trail.


Remedy #3: Implementation• Simulated Test Environment

Increased control over available context. Enables repeatable experiments.

Immersive 3D games engines being used to simulate the physical environment e.g., TATUS[4].

• Smarter Dynamic Reconfiguration

Evaluation of search space.

Delegation to more powerful devices.


Issues #4: Application Scenario• Application Scenario Choice

Original decision to implement a student support system was motivated by access to a group of test subjects – M.Sc. students on their first day.

Delays in acquiring equipment caused this deadline to be missed.

The new application scenario appears not to motivate users as much as we would like – there is nothing at stake.


Remedy #4: Application Scenario• Considering Evaluation during Design

Properties of the application itself influence user motivation [2].

Opportunities for creating engaging applications exist in the computer gaming field as described by Johnson [5].

We are considering whether or not to tell people they will have to answer questions when getting them to use the application i.e., just let them play the game, same approach as taken by Bellotti [6].

Next prototype application is a mobile, context-aware riddle game. Taking findings to date into account during design phase.


References1. Roberts, D. at al. “Evolving Frameworks: A Pattern Language for

Developing Object-Oriented Frameworks”. Pattern Languages of Program Design 3, 1997.

2. Klein, J. et al. "This Computer Responds to User Frustration: Theory, Design, and Results". Interacting with Computers, Volume 14, Issue 2, Elsevier, 2002.

3. Marti, S. "How does the user interface design of mobile devices influence the social impact of mobile communication?" MIT Media Lab, February, 2002.

4. O’Neill, E. et al. "A Testbed for Evaluating Human Interaction with Ubiquitous Computing Environments". In Proceedings of Tridentcom 2005.

5. Johnson, C. "Taking Fun Seriously: Using Cognitive Models to Reason about Interaction with Computer Games". Personal Technologies, Vol. 3, No. 3, 1999.

6. Bellotti, F. et al. “User testing a hypermedia tour guide”. Pervasive Computing, IEEE Apr-Jun 2002 Volume: 1, Issue: 2, pp. 33- 41

Documents

Http:// 1 A Framework for Mobile, Context-Aware Trails-based Applications: Experiences with an Applications-led Approach Cormac Driver