Paper on the Move

 

Paper has many potential advantages in mobile applications and new technologies for digital paper offer the possibility of interweaving the paper and digital worlds. As a demonstrator project, we are developing a mobile tourist information system for this year’s Edinburgh festivals based around an interactive paper map and event brochure and an audio channel.

Despite the emergence of digital technologies for capturing, managing, retrieving and processing information, paper persists as a fundamental resource for many human activities. It has therefore continued to be of great interest to the computer-supported cooperative work (CSCW) and human-computer interaction (HCI) communities. They are interested in studying both the properties of paper and how we use it, with a view to better understanding why it remains as a truly ubiquitous information medium. On the one hand, they want to use the results of their investigations to influence the design of digital technologies, with the ultimate aim of being able to replace paper. On the other hand, some researchers argue for the retention of paper and instead strive for means to interweave paper and digital media, enabling users to freely move back and forth between the printed and digital worlds.

Here we focus on the potential use of digital paper in mobile environments. As a particular application domain, we consider tourism which has been the subject of many projects in ubiquitous and mobile computing. Typically, PDAs are used to provide tourists with, possibly personalised and context-dependent, digital maps and guides. Although many digital forms of tourist information are available nowadays, studies have shown that they are rarely used during visits, where paper continues to prevail in the form of maps and guidebooks. We will describe how technologies for digital paper could be used to support tourists and outline a demonstrator project for the Edinburgh festivals that is currently under development.

Digital Paper

While several projects in the past have sought to bridge the paper and digital divide, recent technological developments make this a realistic option and a number of commercial products are now available using Anoto technology. The technology is based on an almost invisible pattern of infrared-absorbing dots printed on paper and special digital pens which have a camera situated alongside the writing stylus. The pattern of dots encodes x-y positions in a vast virtual document address space. Camera images are recorded and processed in real time to give up to 100 x-y positions per second and enable a good representation of handwriting to be captured. Several pages of handwriting can be stored in the pen before being transmitted to a PC. Commercial products based on this technology include Nokia’s Digital Pen, Logitech’s io Personal Digital Pen and Sony Ericsson’s Chatpen. As a first business solution, Hewlett-Packard has recently released a forms automation system aimed at large enterprises such as insurance companies.

Currently, the focus of commercial products is on information capture for enhanced writing. A number of research products have also investigated technologies for enhanced reading based on some means of creating links to digital materials within printed documents. Many systems use printed visible marks on paper such as standard barcodes or specially printed patterns. While visible encodings have the advantage of making links obvious to users, they can also be extremely disruptive to reading, especially if many links are present.

We participated in the European project Paper++, where an alternative solution for enhanced reading was investigated based on the use of conductive inks to print an almost invisible encoding of position information within a paper page. A pen-like reader was developed that could read the information by measuring inductivity. In contrast to the relatively expensive Anoto-based technologies, the Paper++ technologies could lead to very low cost solutions almost at the level of disposable technologies that could be widely deployed in schools, homes etc.

Our role within the Paper++ project was to develop an open hypermedia system, iServer, based on a generic link framework that allows any form of media to be integrated through a plug-in mechanism. So far plug-ins for digital paper, XHTML documents and video have been developed. These allow not only entire resources to be linked, but also elements within resources as specified through appropriate selector mechanisms. In the case of digital paper, selectors are defined as areas within physical document pages. Links are bi-directional, can have multiple anchors and/or multiple targets and can be nested. The nesting of links is handled through a layering mechanism that relates areas to one of possibly many virtual pages associated with a single physical page. Layers can be activated and ordered dynamically and this, together with user access control, determines the link activated in any context.

We are now investigating the use of digital pens both as a writing device and an interaction device, thereby combining the approaches of enhanced writing and enhanced reading. Since iServer is independent of any specific technology for digital paper, we are able to use Anoto technologies both for the capture of handwriting and the activation of links within a page. However, it is important to stress that in order to do this, we use pens specially modified by Anoto rather than an off-the-shelf product. As an example application area, we are currently developing systems to support tourists on city visits.

Tourists on the Move

Tourism is a domain with considerable potential for the use of mobile technologies and a number of projects have developed PDA-based tourist guides. However, commercially available digital guides have had little success to date and paper maps and guides continue to be considered essential tourist accessories.

A major occupation of tourists is the planning of their activities, both before and during the visit. During the actual visit, tourists will refer to maps and guidebooks to locate themselves, plan activities and find out more about a particular place of interest. Tourist plans are often not too detailed or specific and they may adapt to changes in the weather or the discovery of special events or places of interest along the way. Tourists generally travel in groups and a major part of the enjoyment is discussing what to do and when to do it.

Maps and guidebooks are used in combination and frequent use is made of pointing to relate items in the map and guidebook to each other and also to the environment. Often tourists will work together with the map to try and establish their location, specific landmarks or the direction in which they should travel. To do this, the map may be rotated to align it with the physical environment. Maps are also used as a general reference to the city in terms of the areas within the city and their spatial relationships. Annotations of maps and guidebooks may also play an important role. Routes or places of interest may be marked on a map. Entries in a guidebook may be highlighted or annotated and markers placed in pages.

Although we have only sketched a few aspects of a tourist’s use of maps and guidebooks, there are already a number of factors that are important in considering the design of a mobile tourist information system. Any mobile devices must be light and easy to place in pockets etc. and also low in terms of power consumption. Tourists spend a lot of time combining and comparing information and it is therefore important that they can easily switch back and forth between options and display related information such as map locations and descriptions simultaneously. Since collaboration is central, even if only asking someone for directions, simultaneous viewing of displays should be possible. The small screen sizes and display technologies of current mobile digital devices such as PDAs fail to satisfy all of these requirements.

Paper as a medium has many advantages over digital media in terms of how people can work with it, both individually and in groups. It is light, portable, cheap, robust and power-free. It can be folded, cut and torn. It is much more convenient to scan through a book by rapidly flicking through pages than to browse a digital document. It can easily be annotated in various ways. Paper also supports forms of collaboration and interaction difficult to mimic in the digital world.

While there are many advantages to working with paper, clearly there are also advantages offered by digital media in terms of the storage, management, processing, retrieval and distribution of information. For this reason, we are now investigating means of integrating paper and digital media in an attempt to gain the best of both worlds in mobile environments.

Globis @ Edinburgh Festival

As a demonstrator application in the Paper++ project, we developed an interactive paper map of Zurich with a number of virtual layers to give information at different levels of granularity e.g. the whole city, an area, a street or a specific location. We are currently developing another demonstrator that pushes our research further in terms of integrating various technologies previously developed in the group, testing them in a real-world situation and establishing requirements for a future more advanced information infrastructure for mobile environments.

The situation we have chosen is that of tourists visiting the many festivals held each year in Edinburgh during August. Alongside the famous military tattoo, there is a major international arts festival, a book festival, a film festival, various music festivals and, last but not least, the Fringe Festival with contemporary dance, theatre, music and comedy, that together offer over thirty thousand individual events.

The EdFest system that we are developing not only provides access to information about venues and events, but also allows tourists to enter and share reviews of events and information about restaurants and bars discovered during their visit. Tourists will be provided with a specially designed digitally augmented map and brochure, a digital pen, an earpiece that serves as an audio channel and a wearable computer. As we want to investigate paper-based interaction with information systems, we have explicitly chosen not to provide a digital screen or PDA, although a visual desktop browser interface is provided for possible pre- or post-visit searches. Spaces are provided within the brochure for writing comments about events and restaurants and the location of restaurants can be indicated on the map.

This year, our prototype is based on a client-server architecture and the integration of existing components for digital paper, context-awareness and web publishing. The server basically consists of two of our components, OMSwe and iServer. OMS Web Elements (OMSwe) is an object-oriented database management system empowered to support web publishing. It uses an advanced versioning mechanism to match variants of objects to the context of a request, enabling us to adapt all aspects of information delivery – content, structure and layout – through a single mechanism. In our EdFest prototype, OMSwe is used to provide voice content to a tourist’s earpiece using VoiceXML, a mark-up language for speech-based data. The second component on the server-side is iServer, our cross-media link server developed in the Paper++ project. The iServer also supports dynamic authoring, enabling tourists on the move to annotate their specially designed maps and brochures and share this information with other users through the central server.

Commercially available digital pens based on Anoto technology are designed to work in batch mode. A user fills out a form or writes some pages of text and the actions are stored in the pen. The data will be transferred to a computer when the pen is placed in its cradle or, in the case of pens with wireless connection capabilities, when a special command button printed on the page is selected. We required synchronous communication and hence a pen capable of sending events continuously. Through the support of engineers at Anoto we have been able to get pens originally manufactured by Nokia modified to behave as required.

At the moment, communication is realised using the mobile phone network. Finding your way, knowing where you are and meeting up with friends are all important to the tourist’s experience. Thus, we have included a GPS service in our client device that can determine the position of the tourist and, with the help of the server, allows him to find his way.

New technologies always pose new challenges to their users and through the application of well known principles from cognitive psychology and the area of human-computer interaction, we have tried to design a guide book that is both useable and useful. Evaluating these efforts and learning more about paper-based interaction are also valuable results we hope to gain from the real users at the Edinburgh festival.

Based on our experiences at this year’s Edinburgh festival, we aim to extend the system for next year. Instead of a central server, we aim to move to a peer-to-peer architecture that provides tourists with opportunistic information sharing based on proximity.