Interaction aspects of wearable computing for human communication

DOCTORA L T H E S I S

Luleå University of Technology

Department of Computer Science and Electrical Engineering Media Technology Research Group

2006:60|: 02-5|: - -- 06 ⁄60 -- 

Interaction Aspects of Wearable Computing for

Human Communication

Mikael Drugge

of Wearable Computing for Human Communication

Mikael Drugge

Media Technology Research Group

Department of Computer Science and Electrical Engineering Luleå University of Technology

SE–971 87 Luleå Sweden

December 2006

Supervisor

Ph.D. Peter Parnes, Luleå University of Technology

Abstract

This thesis presents the use of wearable computers for aiding human communication over a distance, focusing on interaction aspects that need to be resolved in order to realize this goal.

As wearable computers by definition are highly mobile, always on, and always accessible, the ability to communicate becomes independent of place, time and situation. This also imposes new requirements on the user interface of the wearable computer, calling for natural and unobtrusive interaction with the user.

One of the key challenges in wearable computing today is to streamline the user’s inter- action, so that it is tailored for the situation at hand. A user interface that takes too much effort to use, interrupts or requires more than a minimum of attention, will inevitably ham- per the user’s ability to perform tasks in real life. At the same time, human communication involves both effort, interruptions and paying attention, so the key is to find a balance where wearable computers can aid human communication without being intrusive. To design user interfaces supporting this, we need to know what roles different aspects of interaction have in the field of wearable computing. In this thesis, the use of wearable computing for aiding human communication is explored around three aspects of interaction.

The first aspect deals with how information can be conveyed by the wearable computer user, allowing a user to retrieve advice and guidance from experts, and remote persons to share experiences over a distance. The thesis presents findings of using wearable computing for sharing knowledge and experience, both for informal exchange among work colleagues, as well as enabling more efficient communication among health-care personnel. The second aspect is based on findings from these trials and concerns how the wearable computer inter- acts with the user. As the user performs tasks in the real world, it is important to determine how different methods of notifying the user affects her attention and performance, in order to design interfaces that are efficient yet pleasant to use. The thesis presents user studies examin- ing the impact of different methods of interruption, and provides guidelines for how to make notifications less intrusive. The third and final aspect considers how the user’s physical inter- action with the wearable computer can be improved. The thesis presents rapid prototyping of systems employing user centric design. Furthermore, a framework for ubiquitous multimedia communication is presented, enabling wearable computers to be dynamically configurable and utilize resources in the environment to supplement the user’s equipment.

All in all, the thesis presents how wearable communications systems can be developed and deployed, how their human-computer interaction should be designed for unobtrusive operation, and how they can come to practical use in real world situations.

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Contents

Abstract iii

Preface xi

Publications xiii

Acknowledgments xv

1 Thesis Introduction 1

1.1 Introduction . . . . 3

1.2 Thesis Organization . . . . 3

1.3 Background and Motivation . . . . 4

1.3.1 Wearable Computing . . . . 4

1.3.2 Ubiquitous and Pervasive Computing . . . . 6

1.3.3 Video Conferencing and E-meetings . . . . 7

1.3.4 Mobile E-meetings . . . . 8

1.3.5 Motivation of Thesis . . . . 11

1.4 Research Questions . . . . 11

1.5 Scope and Delimitation of the Thesis . . . . 14

1.6 Research Methodology . . . . 14

1.7 Summary of Included Publications . . . . 16

1.8 Wearable Computing for Human Communication . . . . 18

1.8.1 Mobile E-Meetings through Wearable Computing . . . . 19

1.8.2 Managing Interruptions and Notifications . . . . 22

1.8.3 Prototyping and Deploying Mobile E-Meeting Systems . . . . 24

1.9 Discussion . . . . 28

1.9.1 Future Research Directions . . . . 31

v

1.9.2 Conclusions . . . . 31

1.10 Personal Contribution . . . . 32

2 Sharing Experience and Knowledge with Wearable Computers 35 2.1 Introduction . . . . 37

2.1.1 Environment for Testing . . . . 38

2.2 Related Work . . . . 38

2.3 The Mobile User . . . . 38

2.3.1 Hardware Equipment . . . . 39

2.3.2 Software Solution . . . . 40

2.4 Beyond Communication . . . . 41

2.4.1 Becoming a Knowledgeable User . . . . 41

2.4.2 Involving External People in Meetings . . . . 42

2.4.3 When Wearable Computer Users Meet . . . . 43

2.5 Evaluation . . . . 44

2.5.1 The Importance of Text . . . . 44

2.5.2 Camera and Video . . . . 46

2.5.3 Microphone and Audio . . . . 46

2.5.4 Transmission of Knowledge . . . . 46

2.6 Conclusions . . . . 47

2.6.1 Future Work . . . . 47

2.7 Acknowledgements . . . . 47

3 Experiences of Using Wearable Computers for Ambient Telepres- ence and Remote Interaction 49 3.1 Introduction . . . . 51

3.1.1 Related Work . . . . 52

3.2 Everyday Telepresence . . . . 54

3.3 Wearable Computers . . . . 56

3.4 Experiences of Telepresence . . . . 58

3.4.1 User Interface Problems . . . . 59

3.4.2 Choice of Media for Communicating . . . . 61

3.5 Evaluation . . . . 62

3.5.1 Time for Setup and Use . . . . 62

3.5.2 Different Levels of Immersion . . . . 63

3.5.3 Appearance and Aesthetics . . . . 66

3.5.4 Remote Interactions made Possible . . . . 68

3.5.5 Summary . . . . 68

3.6 Conclusions . . . . 69

3.6.1 Future Work . . . . 69

3.7 Acknowledgments . . . . 70

4 Methods for Interrupting a Wearable Computer User 71 4.1 Introduction . . . . 73

4.1.1 Related Work . . . . 74

4.2 Experiment . . . . 75

4.2.1 Real World Task . . . . 75

4.2.2 Interruption Task . . . . 76

4.2.3 Combining the Tasks . . . . 76

4.2.4 Treatments . . . . 77

4.3 User Study . . . . 79

4.3.1 Test Session . . . . 79

4.3.2 Apparatus . . . . 80

4.4 Results . . . . 82

4.4.1 Comparison with Base Cases . . . . 83

4.4.2 Pairwise Comparison of Treatments . . . . 84

4.4.3 Comparison with Original Study . . . . 85

4.4.4 Subjective Comments . . . . 85

4.5 Conclusions . . . . 86

4.5.1 Future Work . . . . 86

4.6 Acknowledgments . . . . 86

5 Using the "HotWire" to Study Interruptions in Wearable Com- puting Primary Tasks 87 5.1 Introduction . . . . 89

5.1.1 Motivation . . . . 89

5.1.2 Outline . . . . 90

5.2 Related Work . . . . 90

5.3 Experiment . . . . 91

5.3.1 Primary Task . . . . 91

5.3.2 Interruption Task . . . . 92

5.3.3 Methods for Handling Interruptions . . . . 92

5.4 User Study . . . . 93

5.4.1 Apparatus . . . . 94

5.5 Results . . . . 96

5.5.1 Time . . . . 98

5.5.2 Contacts . . . . 99

5.5.3 Error rate . . . 101

5.5.4 Average age . . . 101

5.6 Evaluating the apparatus . . . 101

5.7 Conclusions . . . 102

5.7.1 Future Work . . . 103

5.8 Acknowledgments . . . 103

6 Wearable Systems in Nursing Home Care: Prototyping Experi- ence 105 6.1 Introduction . . . 107

6.2 Scoping the Project . . . 108

6.3 Paper Prototyping . . . 109

6.3.1 Paper, Pen, and Plastic . . . 109

6.3.2 Paper Prototyping Benefits . . . 110

6.4 Moving to Multimodal Devices . . . 111

6.4.1 Wearable Prototype . . . 111

6.4.2 Communication Application . . . 111

6.4.3 Wizard of Oz Testing . . . 112

6.4.4 Feedback From the Nurses . . . 113

6.5 Final Remarks . . . 114

6.6 Acknowledgments . . . 115

7 Enabling Multimedia Communication using a Dynamic Wearable Computer in Ubiquitous Environments 117 7.1 Introduction . . . 120

7.2 Background and Related Work . . . 121

7.3 The Ubiquitous Communication Management Framework . . . 122

7.3.1 Information Repositories . . . 124

7.3.2 Personal Communication Management Agent . . . 127

7.3.3 Remote Control User Interface . . . 128

7.3.4 Mobility Manager . . . 129

7.4 Evaluation . . . 131

7.4.1 Framework Implementation . . . 132

7.4.2 Message Complexity . . . 135

7.4.3 Bandwith Overhead . . . 136

7.4.4 Time Complexity . . . 137

7.4.5 Proof of Concept . . . 138

7.4.6 Scenario . . . 138

7.4.7 Prototype Implementation . . . 139

7.4.8 Hardware used in the Scenario . . . 140

7.4.9 Evaluation by End Users . . . 141

7.5 Discussion . . . 143

7.6 Acknowledgements . . . 145

Bibliography 147

Preface

The work presented in this thesis has been conducted at Luleå University of Technology (LTU) between the years 2002 and 2006. I started in a project called RadioSphere with the Centre for Distance-spanning Technology (CDT), where the ultimate goal was to proliferate the mobile Internet by providing ubiquitous network access to mobile computers. Among the work needed to help this vision come true, was research in human-computer interaction for highly mobile and portable devices. This brought me in contact with the field of wearable computing, where I together with my colleague Marcus Nilsson became the local pioneers in exploring this research topic at our university.

Much of my early work was to build a foundation of knowledge on how wearable com- puters could be used, creating prototypes which would provide first hand experience in order to provide the essential know-how about wearable computing. As my research group had a long history of research in multimedia communication and online e-meetings between people, my research soon followed along with the goal of enabling and facilitating such e-meetings through wearable computing. This resulted in a number of publications where the concept of using wearable computers for mobile e-meetings was explored.

Realizing that wearable computing was in fact a very broad and highly interdisciplinary field of research, containing topics ranging from software to hardware and human-computer interaction, crossing over into fields such as psychology and ergonomics and even fashion design, I tried to focus my work more on the human-computer interaction aspect. The reason for this choice being that one of the major problems I found when using our wearable com- puters in real-life settings, was that the user interface was highly difficult to get right for a computer supposed to be used in mobile and physically challenging environments, and this was detrimental for the entire concept of mobile e-meetings. One of the inherent properties of a meeting in the real world is that the persons involved interact and interrupt each other, and when meetings are mediated through a computer this happens even more frequently as social cues are lost in the process. Therefore, I did an experiment aimed at finding out how to manage interruptions properly. Because of the depth of this research question, this would turn out to lead to a series of experiments and publications that would continue throughout the years.

After my licentiate thesis in late 2004, I got involved in projects run by the Centre for Distance-spanning Healthcare (CDH). Noticing the need for better communication and the ability to bridge distances between medical workers in the rural parts of northern Sweden, such as enabling a nurse to remotely communicate with a doctor when examining a patient,

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my research became focused on providing mobile e-meetings for such purposes. Because of the precarious situation of deploying novel computing solutions for people who normally deal with humans rather than computers, my research still maintained the ever important goal of making interaction easy and disruption free. Having access to a nursing home in which prototypes could be deployed and experiments conducted, this led to a number of field tests with proof of concept solutions.

In the following autumn and winter of 2005, I was given the opportunity to stay as an

exchange student at the Technologie-Zentrum Informatik (TZI) at the University of Bremen in

Germany. Me being the only researcher in wearable computing back home at LTU, working

together with the many members of the TZI wearable computing research group proved to be

a highly educational and valuable time. Besides gaining new insights in research and research

methodologies related to wearable computing, we also initiated a collaboration around my

interruption studies as interaction was a common research question of ours.

Publications

This doctoral thesis consists of an introduction and six papers. The introductory chapter pro- vides a discussion of all papers and their relationship with each other, together with ideas for future work in the area of research. All papers except one have been published at international peer reviewed conferences, journals, and workshops. I am the main author of four papers and co-author of two papers.

Paper 1 Marcus Nilsson, Mikael Drugge, and Peter Parnes,

“Sharing Experience and Knowledge with Wearable Computers”, In Proceedings of Pervasive 2004 Workshop on Memory and Sharing of Experiences, Vienna, Austria, April 2004.

Paper 2 Mikael Drugge, Marcus Nilsson, Roland Parviainen, and Peter Parnes,

“Experiences of Using Wearable Computers for Ambient Telepresence and Re- mote Interaction”, In Proceedings of the 2004 ACM SIGMM Workshop on Effective Telepresence, New York, USA, October 2004.

Paper 3 Mikael Drugge, Marcus Nilsson, Urban Liljedahl, Kåre Synnes, and Peter Parnes,

“Methods for Interrupting a Wearable Computer User”, In Proceedings of the 8th IEEE International Symposium on Wearable Computers (ISWC’04), Washington DC, USA, November 2004.

Paper 4 Mikael Drugge, Hendrik Witt, Peter Parnes, and Kåre Synnes,

“Using the "HotWire" to Study Interruptions in Wearable Computing Primary Tasks”, In Proceedings of the 10th IEEE International Symposium on Wearable Com- puters (ISWC’06), Montreux, Switzerland, October 2006.

Paper 5 Mikael Drugge, Josef Hallberg, Peter Parnes, and Kåre Synnes,

“Wearable Systems in Nursing Home Care: Prototyping Experience”, In IEEE Pervasive Computing, vol. 5, no. 1, pages 86–91, January–March 2006.

Paper 6 Johan Kristiansson, Mikael Drugge, Josef Hallberg, Peter Parnes, and Kåre Synnes,

“Enabling Multimedia Communication using a Dynamic Wearable Computer in Ubiquitous Environments”, Under review.

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The following publications were intentionally left out from the thesis, either because results have been superseded or made redundant by more recent findings included herein, or because their focus does not lie entirely within the scope of the thesis.

• Hendrik Witt and Mikael Drugge,

“HotWire: An Apparatus for Simulating Primary Tasks in Wearable Comput- ing”, In ACM International Conference on Human Factors in Computing Systems (CHI’06), extended abstracts, Montréal, Canada, April 2006.

• Mikael Drugge, Josef Hallberg, Kåre Synnes, and Peter Parnes,

“Relieving the Medical Workers’ Daily Work Through Wearable and Pervasive Computing”, In 11th International Conference on Concurrent Enterprising (ICE 2005), Munich, Germany, June 2005.

• Marcus Nilsson, Mikael Drugge, Urban Liljedahl, Kåre Synnes, and Peter Parnes,

“A Study on Users’ Preference on Interruption When Using Wearable Computers and Head Mounted Displays”, In Proceedings of the 3rd IEEE International Confer- ence on Pervasive Computing and Communications (PerCom’05), Kauai, USA, March 2005.

• Mikael Drugge, Marcus Nilsson, Kåre Synnes, and Peter Parnes,

“Eventcasting with a Wearable Computer”, In Proceedings of the 4th International

Workshop on Smart Appliances and Wearable Computing (IWSAWC’04), Tokyo, Japan,

March 2004.

Acknowledgments

First, I would like to thank my supervisor Dr. Peter Parnes for all your guidance, support and encouragement to always strive for excellence. I would also like to thank my secondary advisor Dr. Kåre Synnes for your valuable comments, discussions and advice given. A posthumous thanks goes to the late Dr. Dick Schefström for his grand visions that served as inspiration when I first started working here.

Most of my research has been funded by projects run by CDH and CDT, by the VIN- NOVA RadioSphere project, and by the VITAL project supported by the Objective 1 Norra Norrland EU structural fund programme. Further funding has been received by the European Commission through the IST Project wearIT@work (No. IP 004216-2004).

A big thanks goes to all my colleagues in the Media Technology research group and at LTU and CDH/CDT. In particular, I would like to express my gratitude to my fellow graduate students Josef Hallberg, Johan Kristiansson, Marcus Nilsson, Roland Parviainen, Jeremiah Scholl, and Sara Svensson, with whom I’ve spent the most time with over the years. Thank you all for making this a great place to work and conduct research in, and for countless discussions concerning all aspects of life inside and outside the world of research. Without your wits, wisdom and friendship, it would never have been as rewarding to work here.

I would also like to thank the people at TZI at the University of Bremen for welcoming me as a guest researcher. Being involved in your wearable computing research group provided me with valuable insights in the field and research in general. My stay at TZI also led to subsequent collaboration with Hendrik Witt who shared similar research interests, and with whom I had several interesting discussions and experiments conducted with.

Furthermore, some people have always helped reminding me that there is a life outside of research. This includes the fellow buyû in my training group, there can be few better companions than you when venturing the way of the warrior.

A very special thanks goes to the precious persons who are known as friends, I won’t mention any names but I am quite certain you know who you are.

Finally, I would like to thank my parents and sister for always supporting me in whatever endeavour I have undertaken.

Luleå, November 2006 Mikael Drugge

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Thesis Introduction

1

1.1 Introduction

Throughout history, communication has constituted a major part of the evolution of mankind.

Advances in technology have eased how communication can be conveyed, ranging from the use of primitive writing tools for clay and stone, to pens and pencils for writing on paper.

The invention of the printing press and photography enabled an easier way to disseminate information, while telegraphs and telephones, and, in the recent decades, computer networks, made it easier to communicate over a distance. The Internet of today allows audio, video, commentary and illustrations to be shared in real-time, with little or no regard to the physical distance between people. At the same time, the emergence of wireless networks has en- abled communication regardless of the physical location of people, allowing communication through mobile phones, laptops, and handheld computers. The next step in making people more mobile and free from constraints, is the concept of wearable computing — providing unobtrusive assistance and service by bringing the computer so close to the user that it is no longer noticeable. How the user interacts with the wearable computer, or any technology, is essential for how well it can be used for communicating with other people. The less focus that needs to be given to the underlying technology the better, as it allows a person to pay more attention to the contents of the communication. That is, after all, what remains important regardless of any changes in technology.

This doctoral thesis presents research on how to enable mobile e-meetings through wear- able computing, with focus on making the user’s interaction streamlined and unobtrusive.

The overall vision is to have a wearable computing platform that enables its user to com- municate with remote people on demand, while at the same time not being in the way nor impeding the user. As wearable computing is a highly multidisciplinary research topic, the goal of the thesis is not to provide a complete system in terms of software and hardware as a functional product, but rather to point out and provide solutions to the design issues related to human-computer interaction. These issues include the use of computer supported collabo- rative work applications in mobile settings, the importance of designing interaction properly so as not to distract or interrupt users, and the question of how to prototype user interfaces and make them easy to deploy.

1.2 Thesis Organization

The thesis consists of seven parts. This introduction belongs to the first part, while the re- maining six parts each contain a paper that has either been previously published or is currently submitted for review at the time of writing. The published papers are reproduced in original form and have not been modified since the time of publication, with the following exceptions.

• The formatting of the papers has been unified so that they all share a common style and appearance.

• Figures have been resized and repositioned so as to fit aesthetically in the common

layout used.

• Figures, tables and sections have been renumbered to fit into the numbering scheme used throughout the thesis.

• Bibliographical entries and citations have been renumbered, and all references have been moved into a common bibliography at the end of the thesis.

• Editorial changes of grammar and spelling have been done to correct a few minor and obvious errors.

The remainder of this chapter contains background information about wearable comput- ing and e-meetings, as well as a discussion on how these two areas can be combined. Here, the motivation for the research presented in this thesis is also explained. After that, a number of relevant research questions are presented, followed by a discussion of the research method- ology used to address them. Then follows a brief introduction to the papers included in this thesis, and a discussion on how the research questions have been addressed and answered.

Finally, this chapter is concluded by pointing out potential future research directions in this field.

1.3 Background and Motivation

In this section, background information regarding the concepts of wearable computing and mobile e-meetings will be presented. The concepts will be explained separately and put in relation to other areas of research, such as ubiquitous and pervasive computing, as well as traditional video conferencing and online e-meetings. This is followed by a discussion on how the concepts are combined in this thesis, and the motivation for the work and research contained herein.

1.3.1 Wearable Computing

Wearable computing is a paradigm which has evolved in line with three different factors;

reduced size of computers, increased mobility of people, and additional personalization of

devices. Ever since the advent of computers, the trend has been to fit more computing power

into less space. The size of computers have gone from occupying entire rooms, to slightly

smaller mainframe computers, and further on to personal computers stationed at the user’s

desktop. As people are mobile and need access to their computers from other locations than

their desktop, this has proliferated the idea of mobile computing through laptops and hand-

held computers. Designed to be lightweight and small in size, they are easy for the user to

bring along to other places, while still providing the user with a personal and consistent work-

ing environment and user interface regardless of where the user is located. This leads to the

idea of personalization of devices. The desire for personalization has become very apparent

e.g. in mobile phones, which today are highly customizable and can be tailored to the user’s

desires. Albeit this customization still mainly applies to the superficial level, e.g. changing

ring tones and background images, it still points out the desire for people to have their own

device adapted to suit themselves. A related example of this is the Personal Digital Assistant

(PDA) which in addition to providing basic computing tools, also serves as a general calendar and organizer for its user over the entire day. In a sense, a PDA becomes more involved in the user’s personal life, serving as an assistant for the user’s everyday tasks in the real world.

All of these factors combined lead naturally to the paradigm of wearable computing. A wearable computer is a lightweight computer meant to be worn by the user, providing access to computational power from any place and at any time. With more and more functionality being added to mobile phones and handheld computers, it can be difficult to discern what separates a wearable computer from a non-wearable computer, and depending on the defi- nition used the line that separates the two fields is not always very clear. In this thesis, the definition will therefore be that the key element that makes a computer wearable, is how the user’s interaction with it is managed.

In terms of interaction, there are several differences between wearable and non-wearable computers. The list below summarizes the most important ones to give the reader an idea of what kind of interaction is required in wearable computing.

• Mobility: The first difference is that the user uses a wearable computer in a highly mobile setting, e.g. while standing up or walking around, as opposed to sitting down in front of a desktop computer. This alone calls for new kinds of interaction devices, as neither the traditional mouse and keyboard used with a desktop computer are suitable in a more mobile setting.

• Assistance: The second difference is that a wearable computer is aimed more at as- sisting the user with a real world task, rather than the user using it to perform some dedicated task in the virtual world inside the computer. PDAs and mobile phones come closer to a wearable computer in this sense, although they mostly require the user’s con- stant attention when being used. Whether controlled via a stylus pen, touch-sensitive display, or miniature keyboard, all of these interaction methods require the user to fo- cus on the computer rather than the real world while performing the task. Also, the task itself is often related to the device itself, rather than to the task currently performed in the real world.

• Unobtrusiveness: The third and final difference is that a wearable computer should be unobtrusive to use. The user’s physical interaction with it should not impose excessive attention demands, nor should it restrict or encumber the user’s interaction capabilities with the real world. Furthermore, wearable computers are typically dedicated to a sin- gle task, to avoid overwhelming the user with distracting information and nuisances. In comparison, ordinary desktop computers typically present the user with numerous has- sles that impede the user’s performance; ranging from mundane dialog boxes blocking all interaction until they are responded to, to incoming mails or chat messages that in- terrupt and cause the user to perform numerous mental context switches. The severity of all these problems becomes magnified when a wearable computer is used to assist its user in a real world task, and thus calls for more suitable user interfaces being em- ployed.

Wearable computers thus differentiate themselves on many aspects from traditional desk-

top computers, and define themselves primarily based on how the user uses and interacts with

the computer. This paradigm shift of what a computer is and what it can be used for, can also be seen in two neighbouring areas of research, both of which will be briefly introduced in the next section.

1.3.2 Ubiquitous and Pervasive Computing

The terms ubiquitous computing and pervasive computing denote areas of research which are closely related, both to each other and to the field of wearable computing. The idea of bringing computational power away from the desktop and out into the real world is paramount in all three research areas, and the difference is mainly the goals and means by which this can be achieved. The two terms ubiquitous and pervasive are sometimes used interchangeably, but there are some inherent differences in their meaning which should be clarified.

Ubiquitous computing refers to the vision introduced by Mark Weiser in his seminal article [82], where he states that “The most profound technologies are those that disappear.

They weave themselves into the fabric of everyday life until they are indistinguishable from it.” Thus, ubiquitous computing is the idea of having access to computers everywhere — not necessarily as distinct or dedicated machines per se, but rather embedded in everyday objects and accessible throughout a person’s physical environment. Examples of this include the ParcTab [81] ubiquitously available computers for the office, and the MediaCup [23] that augments an ordinary coffee mug with sensors providing context awareness.

Pervasive computing is similar to ubiquitous computing, but refers to the vision of making the computers integrated into the environment and their usage completely transparent for the user. Whereas in ubiquitous computing a user would still interact directly with certain every- day objects containing embedded computers, pervasive computing would have those objects disappear and become invisible, so that the user does not even know they are there. Examples of this include e.g. radio frequency identification (RFID) technology and applications [54], as well as more concrete applications like the ActiveBadge [80] location system.

Wearable computing thus falls within the realm of pervasive computing, as the idea is to have the computer disappear and assist the user while not being noticed. In practice at the time of writing, most wearable computers only partially belong to this realm, as further research is still needed to make them less obtrusive and the interaction more streamlined.

In certain application domains, the use of a wearable computer requires infrastructure

or services provided by ubiquitous or pervasive computing. For example, indoor positioning

systems serve as a prime example of a pervasive computing service that a wearable computing

application may utilize. Another example is the use of ubiquitous computing to extend the

capabilities of a wearable computer, e.g. to be able to delegate computations to more powerful

devices, or utilize terminals and input/output devices in the surrounding environment for

easier interaction. In other scenarios, a pervasive computing system relies on each user having

a wearable computer, e.g. for the purpose of storing private data and avoid security concerns

by the user. All in all, these three areas of research co-exist and all have certain benefits and

drawbacks compared to each other, and as discussed in [68] the best choice is sometimes to

combine them.

1.3.3 Video Conferencing and E-meetings

Video conferencing is the idea of enabling people to meet over a distance. This can be achieved by conveying media such as audio and video from one place to another, so that the people involved get an experience of them being together even though physically separated.

Early video conferencing facilities were taken in use by certain companies and institutions, where dedicated hardware and communication channels were used to connect meeting rooms at different locations with each other. This enabled group meetings of a larger scale, but still required a lot of investments in expensive infrastructure to enable this. These problems became easier to overcome as the Internet started to permeate society, and Internet Protocol (IP) based communication channels could be used more easily to convey the video and audio data. With increased capabilities of personal computers in terms of graphics and sound, and enough computational power to process multimedia content in real time, it was finally possible to achieve video conferencing through ordinary computers. This helped leverage the concept of video conferencing to include other purposes than formal meetings, enabling people to meet informally in groups and communicate in shorter or longer sessions from the comfort of their own desktop.

The term e-meeting denotes such an online group conferencing session which can include video, audio and chat among other media. Rather than requiring a dedicated meeting room equipped with expensive video conferencing hardware, e-meetings can take place from the user’s desktop computer and be used for either formal or informal communication. In the recent years e-meetings have become more commonplace and available to the populace, with programs such as Skype ¹ , ICQ ² , and MSN Messenger ³ being widely used for both leisure and work related communication.

Within the Media Technology research group at Luleå University of Technology, there is a long history of conducting research in collaborative work applications for enabling e- meetings. Early research concerned the development of the mStar [58] architecture, which was used to explore real-time communication between distributed clients and participants.

The research in mStar later resulted in a spin-off company called Marratech AB being formed, which sells, develops, and distributes the commercial Marratech e-meeting software derived from this research.

Marratech can be used in several application domains, ranging from general computer supported collaborative work to distance learning. Within our research group, Marratech is used for holding formal e-meetings as an alternative and complement to physical meetings, but also as a way of providing all members with a continuous sense of presence of each other throughout the day. This latter case is known as the e-corridor — a virtual office landscape in which the group members can interact, communicate, and keep in touch with each other. The e-corridor offers the social benefits of an office landscape, while still allowing each person to decide for themselves to what degree they wish to partake.

Figure 1.1 shows an illustration of what a user’s desktop can look like when using Mar- ratech. To the right, the top window shows continuously updated video thumbnails of all

1

http://www.skype.com/

2

http://www.icq.com/

3

http://messenger.msn.com/

Figure 1.1: A snapshot of the e-corridor as it looks on a user’s desktop.

participants, while the bottom window shows the person currently in focus, e.g. a person who is currently speaking or which the user is otherwise communicating with. The large window to the left shows the shared whiteboard which can be edited by any participant, and which is commonly used to manage planning or illustrate various ideas or concepts during discussions and meetings.

1.3.4 Mobile E-meetings

A mobile e-meeting is an extension of the concept of an ordinary e-meeting, in which one or

more users are being mobile when participating in the meeting. In this thesis, the structure

of mobile e-meetings follow the idea of having a single mobile user of a wearable computer

performing certain tasks “out in the field”, while having one or more users or experts seated at

their desktops participating in the same e-meeting session as the mobile user. Figure 1.2 pro-

vides an illustration of this. The idea is that the mobile user will be able to receive advice and

guidance originating from the experts through the wearable computer, while simultaneously

conveying video, audio, and possibly other media back to the experts so they can follow

the progress of the task being performed. In this thesis, this concept has been dubbed the

knowledgeable user, denoting that the mobile user can perform the tasks with the combined

knowledge of the experts at hand.

Network

Remote experts Wearable computer user

Figure 1.2: The structure of the mobile e-meetings addressed in this thesis.

To exemplify some typical situations in which the knowledgeable user concept is appli- cable, three scenarios are given below. All of these are based on discussions with industrial project partners and people working in the respective professions, and are as such based on real needs identified in the real world. The first example represents a typical “field worker and remote expert” scenario in general. The second example represents a more specialized scenario that is of more critical nature, both in terms of time but also in terms of the safety and security of users. The third and final example represents a less critical but more social scenario, where an e-meeting is used to give workers more time and reduce their workload.

Scenario 1: Electricians working at remote installations. An electrician working with repairing remote installations in rural areas, may sometimes face problems if the installation site is of a highly specialized or unknown nature that the person has not encountered before.

As such, it may be the case that only certain expert electricians with more experience know how to perform the necessary repairs. Because of the rural areas and long distances involved in commuting back and forth, it would be beneficial if the electrician that is already at the site can still perform the repair, instead of spending costly time on transporting an expert to and from the site to aid or replace the electrician. In this situation, a mobile e-meeting becomes a useful way for the expert to convey his knowledge to the electrician, guiding him or her on how to perform the repair properly. Thus, the electrician contacts the main office to get in touch with an expert, and starts an e-meeting with that person. As the electrician will likely need to use both hands and work with small components, it is vital that the e-meeting is unobtrusive for that person, and that video can be continuously conveyed to the expert when guiding the person. The use of wearable computing in this situation, helps making the process of conveying information back and forth less obtrusive and more natural for the electrician.

Through the use of a head-mounted camera, the expert can follow the work through the electrician’s eyes, so to speak, while a head-mounted display can provide the electrician with illustrations and annotated blueprints. Thereby, the electrician can now perform the repair properly thanks to the guidance provided.

Scenario 2: Firefighters in need of remote guidance. Firefighters working with fire extin-

guishing at an emergency scene, often face highly critical situations in terms of time and the

security and safety of people involved. When working at extinguishing fire inside a building, its structure and architectural layout is often unknown at first, forcing the firefighters to build a mental model of it while performing the operation. With heavy smoke and prevailing dark- ness, physical maps and similar material for assistance often becomes impossible to use for the firefighters. This can however be accomplished through the use of wearable computing, and in particular through head-mounted displays mounted inside the firefighters protective helmet and face mask [5]. With such equipment available, the firefighters are able to look at maps over the building presented before their eyes, as well as be notified about important status information regarding their self contained breathing apparatus. In addition, guidance can then also be provided by fire engineers and experts outside the building, who may have a better overview of the scene and can annotate maps and help the firefighters navigate inside the building.

Scenario 3: Medical workers performing routine examinations. Medical workers and nurses often perform a multitude of routine examinations of patients in their daily work.

Some of these examinations are trivial, while others call for the specific competence of a certain profession or individual, such as a physiotherapist, a chiropractor, a medical doctor, or a fellow medical worker with previous experience of that particular patient. In an ideal world, there would be enough resources available in terms of time and money to allow these experts to visit the patient in person, but in practice that is not always the case — causing problems such as stress and discomfort for medical workers and patients alike. Rather than not having access to the expert at all, a compromise would be to make use of that person’s expertise and knowledge even though not physically being there in person. With medical workers equipped with unobtrusive wearable computers, they would be able to contact an available expert on demand through an e-meeting session, in order to let him or her guide the examination remotely over a distance. A specific example of such a situation is a patient with a sore arm that is in the process of healing. Here, a remote physiotherapist can guide a nurse in instructing the patient on how to move the arm, while watching how the patient manages it and thereby make a remote diagnosis of the healing process. Employing wearable computing in situations like these [14], is motivated by the need for medical workers to interact naturally with the patient, rather than focusing on a separate stand-alone computer to facilitate the e-meeting.

Conclusions from the scenarios. What the three scenarios above point out, is the impor-

tance of the role that interaction plays between a user and a wearable computer. In the electri-

cian’s scenario, the field worker should be allowed to interact with the technology in a natural

and intuitive fashion, so that he or she can concentrate fully on performing the necessary re-

pair. In the firefighting scenario, the wearable computer should not cause additional stress

when it notifies the user, e.g. when remote personnel provide advice or guidance in time

critical situations. In the health-care scenario, the wearable computer must be unobtrusive

enough so as not to disrupt the meeting with a patient, yet still allow for communication and

advice regarding medical information being passed back and forth.

1.3.5 Motivation of Thesis

The main motivation for this thesis is to enable mobile e-meetings through wearable comput- ing, with focus on making the user’s interaction as streamlined and unobtrusive as possible.

This concerns both the interaction between regular e-meeting participants and the user of the wearable computer, as well as the user’s interaction with the wearable computer itself. Both of these concerns affect how the user is able to interact with the world surrounding her. As a mobile e-meeting is intended to help the user in performing tasks in the real world, these concerns therefore needs to be addressed.

One of the main problems we have experienced in mobile e-meetings is that they can become too immersive for the user of a wearable computer, thereby distancing the user from the interactions in the real world. At the same time, this immersion serves to offer a rich experience of being in contact with remote participants; the user can sense them as being there, assisting and communicating with them in the virtual world. The key to efficient com- munication, in both the real and virtual world, is to find a proper balance between these two aspects. To succeed in that, the interaction between the user and the wearable computer itself needs to be highly streamlined, natural, and intuitive. In certain application domains, such as those involving many other people in the real world which the user needs to interact with, this becomes even more important.

The primary application domain of choice for the latter part of the thesis has been that of institutionalized health-care, particularly that taking place in nursing homes where nurses attend mainly elderly patients. The rationale for this choice is twofold. First of all, with an elderly generation growing in size, health-care is an important area for research in order to deal with a larger number of elderly in the coming future. Second of all, nursing homes offer a confined and relatively isolated setting in which research can be conducted under more controlled forms. At the same time, they are not as constrained by the very stringent safety and security concerns of e.g. hospitals and emergency clinics, but allows new technologies to be tested and studied in real life scenarios while still maintaining the safety of all people involved. Thus, nursing homes can be highly suitable for conducting applied research in, with real end users and patients ensuring that the research is properly directed at real world problems, while at the same time having the potential for deploying prototypes bringing immediate benefits for the people working there. Furthermore, as the end users in a nursing home tend to demand that their computer systems are easy and unobtrusive to operate, any results and solutions deemed suitable here can be expected to be just as applicable in other, more general, application domains.

1.4 Research Questions

The objective of this thesis is to make mobile e-meetings through wearable computing easier

for the user. To achieve this, some of the problems that appear in this context need to be

investigated further, so that they can be mitigated or solved once a real system for such e-

meetings is to be deployed and taken in use. Primarily, these problems relate to human-

computer interaction issues that occur in the interaction between the user and the wearable

computer. These can be further divided into three specific problem statements. The first deals with how information can be conveyed by the wearable computer user, allowing a user to retrieve advice and guidance from experts, and remote persons to share experiences over a distance. The second concerns how the wearable computer directly interacts with the user, as it is important to determine how different methods of notifying the user affects her attention and performance, in order to design interfaces that are efficient yet pleasant to use. The third considers how the user’s physical interaction with the wearable computer can be improved, by prototyping entire communications systems for use and deployment in real world situations.

These three general statements can in turn be classified into more specific research questions, which will be described and discussed further in this section.

1. By what means can communication take place in mobile e-meetings through wear- able computing, and what media are relevant to focus on for this purpose? Mobile e-meetings meant to be participated in by a user of a wearable computer can differ vastly from traditional non-mobile e-meetings. This affects what media are useful and needed by the mobile user. The use of video in e-meetings is typically used to provide all participants with a sense of awareness of each other, whereas for the wearable computer user this aware- ness can be undesirable as the user may need to focus on the real world around her. The use of audio differs in a similar manner; because the mobile user is in a more dynamic and less controlled environment, the audio channel may not always be the most appropriate means to convey information. For example, chat or whiteboard drawings, may be better suited to convey an idea instead of using voice communication that requires a person’s direct and continuous attention. In order to be able to construct mobile e-meeting systems, the use of different media needs to be explored further to determine their relevance and usefulness for wearable computing scenarios.

2. How can mobile e-meetings be seamlessly used and employed in real life scenarios?

In the kind of mobile e-meetings focused on in this thesis there are two sides; the mobile user of the wearable computer, and the remaining stationary participants. This research question concerns the stationary participants’ experience of the e-meeting. Can and will those par- ticipants find the e-meeting useful or not, and what aspects of the mobile user’s interaction must be improved to provide an experience that is good enough? Furthermore, seamlessness from the stationary participants’ side is important to provide a good experience for them, so that they can enter the e-meeting session and still grasp the situation and task at hand. Thus, this is one question that needs to be addressed when creating a wearable system for mobile e-meetings.

3. Given a number of methods to interrupt a user, how should these be used so as not to

increase the user’s cognitive workload more than needed? A driving idea of wearable

computing is that the computer should assist its user in performing real world tasks. By

definition, the concept of wearable computing therefore expects the user to primarily focus

on the real world, rather than on the computer itself which is often the case in traditional

desktop computing. Thus, in mobile e-meetings, the idea is for advice and support to reach

the user of the wearable computer in an unobtrusive manner, so that the user is not interrupted

more than necessary. This is important as scenarios encountered in the real world can be of critical nature, where the user may be in a difficult situation while still requiring support through the wearable computer. In such situations, the proper handling of interruption can be vital for the safety and security of the user, and also to provide the user with an efficient and streamlined interaction with the wearable computer in general.

4. How can a typical wearable computing scenario from real life be modeled as an ex- perimental setup, in order to evaluate wearable user interfaces in a reliable and valid manner? With the goal of designing streamlined and unobtrusive user interfaces for wear- able computers, it becomes important to have suitable means for assessing the effect that the interface will have on its user. In the real world, there are a number of nuisance factors that cannot be accommodated for, leading to the risk of experiments becoming unreliable if they are performed solely in that domain. For this reason, it is important to find an apparatus that allows an arbitrary user interface to be evaluated in a reliable and reproducible manner, while retaining the properties of a typical wearable computing scenario to make the experiment valid.

5. What methodologies are useful when prototyping easy to interact with wearable computing e-meeting systems and engaging end users in the process? In order for the user’s interaction with the wearable computer to become unobtrusive and accepted, great care needs to be taken to the end users’ work situation and their idea of what constitutes proper design. Involving the end users in the design process is one way to ensure that the resulting wearable computing system will be useful, as they are the ones with the expertise to decide what features are needed and what should and should not be part of the solution.

This question involves both the physical appearance of the wearable computer, as well as the functionality and interaction means provided in terms of hardware and software.

6. What functionality is needed to allow users to automatically combine and switch

between resources available in the wearable computer and in the surrounding environ-

ment? Just as there is no single program that fits all purposes on a desktop computer, there

is no single wearable computing design that fits all purposes in real life. This can be the case

even for smaller and more constrained application domains, where there is still a need to dy-

namically tailor the wearable computer for the task at hand. With a wearable computer meant

to be deployed and used in a real world scenario, the ability for the end users themselves to

perform this tailoring becomes critical for the long term acceptance of such a system. This

question concerns how a wearable computer can be dynamically configured, by combining

and switching between resources useful for an e-meeting. Such resources can include, for ex-

ample, head-mounted displays, external displays, television sets, and on-body or stationary

office cameras and microphones. Allowing the user to automatically combine these resources

on demand, would mean that she can decide what resources and means for interaction that

are needed for the task at hand, and subsequently perform the task easier without being ham-

pered by needless equipment or missing vital functionality. Naturally, this calls for an easy

way for the end users to perform this configuration, without delving into technical details and

interfacing problems.

1.5 Scope and Delimitation of the Thesis

It should be acknowledged that creating a mobile e-meeting system that suits all kinds of application domains is not feasible within the scope of this thesis. Each application domain contains unique situations, and the needs in each situation can vary depending on the context of the user. The application domain for this thesis has therefore primarily been constrained to that of institutionalized health-care, where nurses, doctors, and medical workers need to keep in contact with each other. Even with this constraint applied, the situations encountered within health-care can be very heterogeneous. The thesis addresses a subset of the situations which occur commonly, in order to provide a solution that in further research can be adapted to handle other kinds of situations as well.

Human-computer interaction is an interdisciplinary research topic, and even when applied in the more narrow field of wearable computing, it still covers a large number of aspects that can and need to be dealt with. In this thesis, emphasis has been given to how the wearable computer can notify and interrupt its user in an unobtrusive manner, as this becomes relevant e.g. in the case of presenting information for the user in an e-meeting. Furthermore, emphasis has also been given to the way the user interacts with the wearable computer, both in terms of hardware and input/output devices on the computer or in the surrounding environment.

Certain assumptions have further been made regarding the network over which an e- meeting session is conveyed. It is assumed that in the situations where mobile e-meetings will be employed, there is access to a suitable IP based network, e.g. typically via an IEEE 802.11b wireless network, to which the wearable computer can be connected for receiving and transmitting media streams. This is a realistic assumption, as the health-care facilities and scenarios which this thesis has focused on have all had such wireless networks available for use. In the future, it is also expected that more and more facilities will be equipped with wireless networks, further enabling mobile e-meetings in such locations. It should be pointed out that the thesis will not focus on research issues in computer networking, nor in the issues of encoding multimedia data to be sent over wireless networks.

During the development of the prototypes, ergonomic constraints and physiological con- siderations of the wearable computers have been addressed to the extent permitted by the available budget and equipment available. That is, prototypes have been built so as to become usable for proof of concept tests and shorter user studies, and in certain cases also for longer term studies covering several weeks. However, for wearable computers to be deployed for actual use as functional products, ergonomic constraints must be further taken into account to make them easy to wear, as well as ensuring long term stability of operation and durability of the hardware used. The publications contained in this thesis discusses a number of these issues encountered in real world tests, to serve as initial guidelines for further development of such products.

1.6 Research Methodology

The research presented in this thesis has been conducted with the ambition to solve actual

problems found in the real world. This has been accomplished by working in research projects

with representatives from industry as well as academia, where the former part often has the goal of seeing a return on investment and create products based on the research results. In turn, this has called for a research methodology that is both applied and practical in nature, resulting in prototypes and artifacts which can be taken in use in real life and demonstrate the solutions proposed. Though the prototypes by themselves may not always yield scientific results suitable for publication, they can still be used to facilitate research being conducted through the use and deployment of them.

A problem of applied research conducted in the real world, with real users and real prob- lems, is that experiments can become dependent on the specific prototypes used and thereby make the results difficult to generalize and reproduce. On the other hand, experiments con- ducted in the real world has a benefit that is often missed in more controlled laboratory stud- ies, namely that the experiment becomes exploratory in nature, and while conducting the experiment new factors are often revealed that were not conceived of before. Research based on prototypes can mean that the development will require large amounts of time and effort, with little or no scientific data resulting from such work. However, once having a prototype available, new findings can often be made which would otherwise have been neglected or not uncovered by other means.

Within this thesis, the Marratech e-meeting system has been extensively used as a basis for the prototypes used. As Marratech is the result of early research in my research group, access to its source code has been granted so that necessary modifications and further de- velopment has been possible. This has had the advantage of prototyping wearable platforms using software that is stable and sold as a commercial product, thereby avoiding many of the bugs and minor nuisances which can otherwise distract a user. In order to keep the research independent from the actual software, care has been taken not to investigate the Marratech application per se, but rather what can be achieved by the use of such software. In all pro- totypes, it would therefore have been possible to utilize other software, either free and open source programs such as Vic/Vat [49], or another commercial product.

Within experimental sciences, the terms validity and reliability are often used when dis- cussing the usefulness and trustworthiness of the research and its results. Validity means that the experiment measures what is intended to be measured, while reliability means that the results gained from the experiment will remain consistent over repeated measurements.

In practice, it can be very difficult to make experiments conducted outside of a laboratory setting valid and reliable. As the real world outside a laboratory is dynamic and changing, and contains a vast number of nuisance factors that cannot be accommodated for, validity can be hard to ensure because it is not known what factors contribute to the result. Due of this, the results may also become unreliable as the uncontrolled factors cause different results for repeated experiments.

As the validity and reliability of experiments conducted in a real world setting can be

hard to ensure, simulations are often used to assure that all factors can be controlled for,

while allowing an easy way to reproduce and repeat experiments with consistent results. A

simulator facilitates an experiment being set up in a highly controlled environment, with all

or most factors accommodated for before, during, and after the simulation. The advantage

of simulations are clear in some disciplines, such as computer networking and algorithm

theory, as experiments as well as resulting prototypes and products will mainly run inside

a similarly controlled environment where nuisance factors are not really an issue. For the field of wearable computing, the use of simulations other than for very specific aspects is difficult. Wearable computers are by definition meant to be used by people in an immense number of different real world scenarios. The wearable computer hardware used, the means provided for interaction, and the support it provides to the user, are all factors which can be varied ad infinitum. Being a relatively young research discipline at the time of writing, the characteristics of these factors are not well known, thereby making proper simulators for wearable computers and their use a grand challenge.

The research and results presented in this thesis are based primarily on real world studies and laboratory experiments, and to a lesser degree on simulations for certain aspects of what has been studied. Initially, the research was exploratory in nature by taking prototypes into the real world to see how they could be used, as well as determine what problems were the most relevant to solve within the area of interaction with wearable computers. Because of the novelty of using wearable computers for human communication, this step was necessary in order to create a foundation of knowledge regarding this topic. Later on, laboratory studies were used to examine how different methods for interrupting the user affected that person’s performance. At first, these were highly controlled and simplified to ensure a high validity of the experiment’s results, for example by studying subsets of a wearable computer such as the head-mounted display — the primary visual means for interacting with it. The first experiments also partially used simulations to represent the primary physical task performed by the wearable computer user, in order to ensure that all factors could be accommodated for in the given experiment. Later on, these experiments resulted in an evaluation apparatus that represents a physical primary task, allowing laboratory experiments more realistically simulating real world use of a wearable computer, while maintaining a high level of validity and reliability.

1.7 Summary of Included Publications

In this section, each publication included in the thesis will be briefly presented. The papers in parts 2 and 3 present early findings related to the field of human communication through wearable computing, presenting an overview of what can be done with such technology, as well as problems that need to be addressed such as creating unobtrusive user interfaces. The papers in parts 4 and 5 present user studies aimed at finding out proper ways to interrupt and notify the user of a wearable computer, while also presenting an evaluation apparatus derived for evaluating wearable user interfaces. The papers in parts 6 and 7 present prototyping of wearable computing e-meeting systems for use in the real world, and a software framework that allows for extending the input and output capabilities of a wearable computer into a ubiquitous computing environment. A schematic overview of the topics covered by the papers is shown in figure 1.3. Following, each paper will be described in further detail with the research problems focused on in this thesis highlighted.

Paper 1: Sharing Experience and Knowledge with Wearable Computers. The first pa-

per addresses the use of a wearable computer for sharing experiences and conveying knowl-

Figure 1.3: Overview of the topics covered by the papers.

edge between people, introducing the concept of the Knowledgeable User. Emphasis is laid on how the user of a wearable computer can represent the combined knowledge of a group by acting as a mediator of the bits of information that each member contributes with. Real life studies at different events, fairs, and exhibitions have been performed to explore and evaluate a prototype communication system enabling this.

Paper 2: Experiences of Using Wearable Computers for Ambient Telepresence and Re-

mote Interaction. The second paper continues the exploration of communication based on

the telepresence aspect of wearable computing. Focus is laid on how to enable remote partic-

ipants to virtually accompany a person equipped with a wearable computer, allowing them to

experience a remote location and gain knowledge from other people being there. In contrast

to the first paper dealing with information originating from a remote group, this paper exam-

ines the issue from the opposite perspective — information being conveyed to the group. The

current wearable computer is evaluated in terms of advantages and drawbacks, with their re-

sulting effects brought forward and described together with recommendations for improving

the platform’s usability.

Paper 3: Methods for Interrupting a Wearable Computer User. The third paper presents a user study of different methods for interrupting the user of a wearable computer, as this was found to be a problematic issue in the studies and field trials discussed in the first two papers.

Knowledge of what ways there are to notify users without increasing their cognitive work- load is important, and this becomes especially evident in communication systems such as the aforementioned wearable platform. The results from the study suggest suitable methods by which to interrupt the user, which can thereby help make a wearable computer less obtrusive and more natural to use.

Paper 4: Using the "HotWire" to Study Interruptions in Wearable Computing Pri- mary Tasks. The fourth paper presents a follow-up user study regarding the appropriate management of interruptions. The experiment from the third paper is extended and brought into a typical wearable computing scenario involving a physical primary task. The results both confirm and complement earlier findings, highlighting the relevant issues to consider when designing user interfaces for wearable computers. Furthermore, an evaluation appara- tus dubbed the HotWire is introduced, which can simulate typical wearable computing sce- narios in laboratory experiments, embodying the characteristics of wearable computers being used in mobile, physical, and practical tasks demanding the user’s attention.

Paper 5: Wearable Systems in Nursing Home Care: Prototyping Experience. The fifth paper presents the prototyping of a wearable computing system for providing communication among nurses in a nursing home. The nurses’ needs are uncovered through an ethnographical study, revealing that improved communication among personnel and remote medical workers is highly desirable. This is followed by participatory design events in which a wearable system is prototyped in terms of functionality and interaction. Paper prototyping as well as Wizard of Oz prototyping are employed to involve the end users in the design process.

Paper 6: Enabling Multimedia Communication using a Dynamic Wearable Computer in Ubiquitous Environments. The sixth paper presents an underlying framework for en- abling ubiquitous multimedia communication. This complements the design and prototyping discussed in the fifth paper, as the framework allows for further customization by the end user also during run-time. The driving concept of the framework is that of the Dynamic Wearable Computer, where the user only needs to wear the interaction devices needed for the task at hand, and is able to utilize external media resources found in the environment to extend the wearable computer’s capabilities.

1.8 Wearable Computing for Human Communication

In this section, the topic of wearable computing for human communication will be presented

in further detail. With basis in the papers summarized in the previous section, three different

aspects will be discussed. These include the aspect of how mobile e-meetings can be con-

ducted through wearable computing, how interruptions and notifications should be managed