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Tabletops: Interactive Horizontal Displays for Ubiquitous Computing Christian Müller-Tomfelde, CSIRO ICT Centre, Australia Morten Fjeld, t2i Lab, Chalmers University of Technology, Sweden
The hype cycle points to widespread adoption of tabletop systems within the next decade.
ables are part of our everyday lives. We use them at home and at work, to play and to eat, and for collaboration. Given the ubiquity of one of the world’s oldest forms of furniture, researchers have long envisioned integrating computers into tabletops. After nearly two decades of R&D and product design, interactive horizontal display technology ha s fina lly reached a high level of maturity. Tabletop systems embody the “boards” of Mark Weiser’s vision of three types of ubiquitous computing devices (“The Computer for the 21st Century,” Scientific American, Feb. 1991, pp. 94-104). Weiser foresaw the emergence of wearable centimetersize “tabs,” handheld decimeter-size “pads,” and meter-size interactive display devices. As Figure 1 shows, tabletops enrich the ubicomp setting by providing an unconstrained display orientation, allowing the placement of physical objects on them, and offering a group interface with egalitarian access. In these systems, the computer as we know it disappears. Although there is a vibrant, wellestablished research community
and several off-the-shelf products are available, tabletop systems remain a niche market. This isn’t unusual; new information and communication technologies often face long adoption periods. To determine when adoption of horizontal displays might accelerate, and what they might look like, we used the hype cycle to analyze the evolution of tabletop technologies and outline potential trends. The advent of Microsoft Surface 2.0, which closely integrates display pixels and multitouch sensors, points to future systems being much thinner—perhaps as thin as a tablecloth.
THE TABLETOP PHENOMENON Based on previous research, we considered the tabletop phenomenon from three different perspectives: research, technologies, and products (“A Short History of Tabletop Research,” Technologies and Products,” Tabletops—Horizontal Interactive Displays, C. Müller-Tomfelde, ed., Springer, 2010, pp. 1-24). These categories encompass computer science, software and hardware engineering, human-computer interaction (HCI),
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and computer-supported cooperative work (CSCW). As for research, we recently counted Google Scholar hits for query terms such as “tabletop” or “horizontal display” to identify the 10 most cited publications on tabletop systems. Some of these works address collaboration scenarios, while others focus on technological aspects. With respect to technologies, we identified major subcomponents of tabletop systems—for example, touch and display technology. Tabletop products have been around since the mid-1990s. Some have been the result of joint efforts between research labs and industrial partners. Others were funded by national government agencies to facilitate technology transfer from the lab to the marketplace. In recent years, several off-the-shelf tabletop solutions have become available. There are various ways to analyze a technology’s evolution from early experimental development to market sustainability. For instance, the performance S-curve models a technology’s performance over time, while the adoption curve shows when d i f ferent ma rket
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TABLETOP HYPE CYCLE
segments adopt new technology—for example, by dividing customers into early and late adopters. The hype cycle visually illustrates the relative maturity of technologies within a certain domain (J. Fenn and M. Raskino, Mastering the Hype Cycle: How to Choose the Right Innovation and the Right Time, Harvard Business Press, 2008). While the cycle reflects objective figures such as performance values or market penetration data, it also accounts for people’s attitudes toward technologies and assumes that excessive enthusiasm, or hype, precedes technological maturity. Researchers originally conceived the hype cycle to provide a snapshot of a specific technology domain to guide investment: it plots the technology’s visibility and expectations against its relative maturity. We used the hype cycle to combine multiple perspectives on tabletop technology into one overview of the tabletop phenomenon and possible future trends.
The ideal hype cycle is divided into five phases: 1. The appearance of a new technology triggers rising expectations; researchers and journalists investigate the technology and explain its potential. 2. Visibility and expectations peak, and the technology becomes overrated due to excessive enthusiasm. 3. Failures and high prices in the market lead to disillusionment, and expectations enter a trough. 4. Consolidated technologies are better understood, and expectations start increasing again. 5. Mainstream productivity reaches a plateau. Figure 2 maps selected tabletop research, technologies, and products on a time line against visibility and expectations on a typical hype cycle. The figure shows the technology
Visibility and expectations
Research Research and technology Technology Products
Peak of inflated expectations
Tabletop augmented reality DigitalDesk
Slope of enlightenment
Plateau of productivity
Smart board plasma BUILD-IT
metaDESK VisionMaker 2000
Microsoft Surface Circle Twelve MultiTouch Cell Smart Table
Trough of disillusionment
First Tabletop Workshop
trigger, peak of inflated expectations, and trough of disillusionment, while the slope of enlightenment and plateau of productivity can be expected in the near future. Researchers introduced lab tabletop prototypes including ClearBoard, Active Desk, DigitalDesk, and Bricks in the early to mid-1990s. Government-funded research activities led to
reacTable* Low-cost multitouch FTIR
CSCW Conference Session: Tabletop design
ClearBoard Active Desk
Figure 1. Tabletop systems enrich the ubiquitous computing setting by providing an unconstrained display orientation, allowing the placement of physical objects on them, and offering a group interface with egalitarian access.
Multitouch OLED Microsoft Surface 2.0
Figure 2. The hype cycle of tabletop research, technologies, and products over three decades.
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Figure 3. Important research prototypes and commercial tabletop systems of the last 20 years. From left to right, top row: ClearBoard, 1992 (photo courtesy of NTT Human Interface Laboratories); Active Desk, 1992 (photo courtesy of Bill Buxton), metaDESK, 1997 (photo courtesy of Tangible Media Group, MIT Media Lab); middle row: BUILD-IT, 1998 (photo courtesy of Peter Troxler); InteracTable, 1999 (photo courtesy of Fraunhofer-IPSI/GMD-IPSI); DiamondTouch, 2001 (photo courtesy of Circle Twelve Inc.); bottom row: SmartSkin, 2002 (photo courtesy of Jun Rekimoto); Microsoft Surface, 2007 (photo courtesy of Microsoft); Smart Table, 2008 (photo copyright SMART Technologies. All rights reserved).
commercial offerings such as VisionMaker that further fueled research efforts like metaDESK. In the late 1990s, researchers explored new technologies such as augmented surfaces, smart board plasma displays, and augmented realit y. Protot ype collaborative design and planning systems, such as InteracTable, were commercialized in 2001. Meanwhile, the development of multitouch and multiuser technologies such as DiamondTouch and SmartSkin in the early 2000s boosted interest in tabletop systems. The 2004 CSCW conference (www. acm.org/conferences/cscw2004) fea-
tured several papers on tabletop research as well as a session on tabletop design. A year later, important publications on tabletop tangibility, the reacTable* system, and low-cost, multitouch FTIR (frustrated total internal reflection) technology led to extensive media coverage. In 2006, the international research community initiated the Workshop on Horizontal Interactive Human-Computer Systems (“Tabletop”), which in 2009 became what is now the Conference on Interactive Tabletops and Surfaces (ITS; http:// its2011.jp and http://its2012conf.org). In 2007, Microsoft launched Surface, followed by Circle Twelve’s
DT107 (the commercial version of DiamondTouch), MultiTouch Cell, and the Smart Table in 2008. These products were more mature than peak prototypes and all featured multitouch technologies. However, their high costs dampened public enthusiasm and disillusioned some tech analysts. Corresponding with the trough of the hype cycle, 2011 saw the introduction of simple multitouch overlays to existing tabletop displays.
TABLETOP EVOLUTION It’s not surprising that tabletop evolution, visually chronicled in Figure 3, has taken more than a
decade. Technology product innovation is “low-amplitude and takes place over a long period,” argues Microsoft researcher Bill Buxton, who cites as an example the mouse’s 30-year-long history (“The Long Nose of Innovation,” Bloomberg Businessweek, 2 Jan. 2008; www.businessweek. com /innovate/content /ja n2008/ id2008012_297369.htm). This view echoes a 2003 report by the National Research Council’s Computer Science and Telecommunications Board, Innovation in Information Technology, which describes a “long, unpredictable incubation period between initial exploration and commercial deployment” (www.nap.edu/openbook. php?isbn=0309089808). Dating the start of the tabletop phenomenon to the early 1990s, we can expect a mainstream tabletop market to emerge around 2020.
Hype cycle phases Government funding and industry cooperation were key to the development of tabletop systems during the technology trigger phase. However, these products were highly customized and too expensive for wide-scale adoption. The tabletop peak period was characterized by extended research and publication activities, as well as highly visible media presentations of, for example, multitouch technologies. In the postpeak period, off-theshelf solutions became available and the performance of secondgeneration products improved. Costs, however, for wide-scale deployment remained prohibitive. T he cl i m b up t he slop e of enlightenment from the trough of disillusionment began with the launch of new technologies such as Surface 2.0 that closely integrate display pixels and multitouch sensors and could allow very small form factors. The hype that tabletops initially generated corresponded with a
change in envisioned applications. Most prepeak scenarios involved their use in office environments, especially in support of small group collaborations. Postpeak scenarios, however, have focused on the education, hospitality, entertainment, performing arts, and consumer electronics domains.
Paradigm shifts The hype cycle also reveals three major paradigm shifts: • 1998—from lab protot ypes to rea l-world collaborative applications • 2001—from single-touch to multitouch and tangibility • 2009—from projection to direct display technology Early 1990s research focused on laboratory prototypes. By the end of the same decade, novel approaches emphasized group work in office environments. BUILD-IT (M. Fjeld, M. Bischel, and M. Rauterberg, “BUILD-IT: An Intuitive Design Tool Based on Direct Object Manipulation,” Gesture and Sign Language in HumanComputer Interaction, LNAI 1371, Springer, 1998, pp. 297-308) and InteracTable, created in 1999 as part of the i-LAND project (www. ipsi.fraunhofer.de/ambiente/english/ projekte/projekte/ineractable.html), represent this transition in research. The first touch-based devices connected to computer systems essentia lly replaced mousebased input. Reliable multitouch technologies entered the field in 2001 with Mitsubishi’s DiamondTouch (now DT107; www.circlet welve. com), a device that “allows multiple, simultaneous users to interact in an intuitive fashion.” The tangibility aspect of tabletops systems also became a popular research topic at that time. A crucial factor in tabletop system construction is the display, which has led technology development. Data projectors were widely used in
interactive tabletops beginning in the 1990s. By the end of the decade, large-size plasma display panels became commercially available, enabling tabletop systems without the bulkiness of rear projection. Recent systems such as FlatFrog (http://flatfrog.com), Displax (www. displax.com), and Microsoft Surface 2.0 combine large-size LCDs (diagonal > 40 inches) with multitouch sensor technology. This development is paving the way to slimmer form factors, and might culminate in the “interactive tablecloth.”
he hype cycle points to increa sing adopt ion of tabletop systems within the next decade. Ultimately, affordable and reliable products that complement the networked lifestyle of future consumers will appear on the market. In the meantime, emerging technologies could accelerate current trends, including integration of organic light-emitting displays (OLEDs) with multitouch technology and a new unobtrusive way to detect and distinguish input from users concurrently to better support group collaboration. Christian Müller-Tomfelde is a research scientist and project leader at the ICT Centre of the Commonwealth Scientific and Industrial Research Organisation (CSIRO) in Sydney, Australia. Contact him at christian. [email protected]
Morten Fjeld is a researcher in the Department of Applied Information Technology at Chalmers University of Technology and runs the TableTop Interaction Laboratory (www.t2i.se) in Gothenburg, Sweden. Contact him at [email protected]
Editor: Albrecht Schmidt, University of Stuttgart, Germany; [email protected]
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