Presently, most AR research is concerned with live video imagery and it’s processing, which allows the addition of live-rendered 3D digital images. This new augmented reality is viewable through a suitably equipped device, which incorporates a camera, a screen and a CPU capable of running specially developed software. This software is written by specialist software programmers, with knowledge of optics, 3D-image rendering, screen design and human interfaces. The work is time consuming and difficult, but since there is little competition in this field, the rare breakthroughs that do occur are as a result of capital investment: something not willingly given to developers of such a nascent technology.
What is exciting about AR research is that once the work is done, its potential is immediately seen, since in essence it is a very simple concept. All that is required from the user is their AR device and a real world target. The target is an object in the real world environment that the software is trained to identify. Typically, these are specially designed black and white cards known as markers:
An AR marker, this one relates to a 3D model of Doctor Who's Tardis in Gameware's HARVEE kit
These assist the recognition software in judging viewing altitude, distance and angle. Upon identification of a marker, the software will project or superimpose a virtual object or graphical overlay above the target, which becomes viewable on the screen of the AR device. As the device moves, the digital object orients in relation to the target in real-time:
Augmented Reality in action, multiple markers in use on the HARVEE system on a Nokia N73
The goal of some AR research is to free devices from markers, to teach AR devices to make judgements about spatial movements without fixed reference points. This is the cutting edge of AR research: markerless tracking. Most contemporary research, however, uses either marker-based or GPS information to process an environment.
Marker-based tracking is suited to local AR on a small scale, such as the Invisible Train Project (Wagner et al., 2005) in which players collaboratively keep virtual trains from colliding on a real world toy train track, making changes using their touch-screen handheld computers:
The Invisible Train Project (Wagner et al., 2005)
GPS tracking is best applied to large scale AR projects, such as ARQuake (Thomas et al, 2000), which exploits a scale virtual model of the University of Adelaide and a modified Quake engine to place on-campus players into a ‘first-person-shooter’. This application employs use of a headset, wearable computer, and a digital compass, which offer the effect that enemies appear to walk the corridors and ‘hide’ around corners. Players shoot with a motion-sensing arcade gun, but the overall effect is quite crude:
ARQuake (Thomas et al, 2000)
More data input would make the game run smoother and would provide a more immersive player experience. The best applications of AR will exploit multiple data inputs, so that large-scale applications might have the precision of marker-based applications whilst remaining location-aware.
Readers of this blog will be aware that AR’s flexibility as a platform lends applicability to a huge range of fields:
- Current academic work uses AR to treat neurological conditions: AR-enabled projections have successfully cured cockroach phobia in some patients (Botella et al., 2005);
- There are a wide range of civic and architectural uses: Roberts et al. (2002) have developed AR software that enables engineers to observe the locations of underground pipes and wires in situ, without the need schematics
- AR offers a potentially rich resource to the tourism industry: the Virtuoso project (Wagner et al., 2005) is a handheld computer program that guides visitors around an AR enabled gallery, providing additional aural and visual information suited to each artefact;
The first commercial work in the AR space was far more playful, however: AR development in media presentations for television has led to such primetime projects as Time Commanders (Lion TV for BBC2, 2003-2005) in which contestants oversee an AR-enabled battlefield, and strategise to defeat the opposing army, and FightBox (Bomb Productions for BBC2, 2003) in which players build avatars to compete in an AR ‘beat-em-up’ that is filmed in front of a live audience; T-Immersion (2003- ) produce interactive visual installations for theme parks and trade expositions; other work is much more simple, in one case the BBC commissioned an AR remote-control virtual Dalek meant for mobile phones, due for free download from BBC Online:
A Dalek, screenshot taken from HARVEE's development platform (work in progress)
The next entry in this series is a case study in AR development. If you haven’t already done so, please follow me on Twitter or grab an 
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Summary So Far
In summary, Mobile AR has many paths leading to it. It is this convergence of various paths that makes a true historical appraisal of this technology difficult to achieve. However, I have highlighted facets of its contributing technologies that assist in the developing picture of the implications that Mobile AR has in store. A hybridisation of a number of different technologies, Mobile AR embodies the most gainful properties of its three core technologies: This analyst sees Mobile AR as a logical progression from VR, but recognises its ideological rather than technological founding. The hardware basis of Mobile AR stems from current mobile telephony trends that exploit the growing capabilities of Smartphone devices. The VR philosophy and the mobile technology are fused through the Internet, the means for enabling context-based, live-updating content, and housing databases of developer-built and user-generated digital objects and elements, whilst connecting users across the world.
I have shown that where the interest in VR technologies dwindled due to its limited real-world applicability, Mobile Internet also lacks in comparison to Mobile AR and its massive scope for intuitive, immersive and realistic interpretations of digital information. Wearable AR computing shares VR’s weaknesses, despite keeping the user firmly grounded in physical reality. Mobile AR offers a solution that places the power of these complex systems into a mobile telephone: the ubiquitous technology of our generation. This new platform solves several problems at once, most importantly for AR developers and interested Blue-chip parties, market readiness. Developing for Mobile AR is simply the commercially sensible thing to do, since the related industries are already making the changes required for its mass-distribution.
Like most nascent technologies, AR’s success depends on its commercial viability and financial investment, thus most sensible commercial developers of AR technologies are working on projects for the entertainment and advertising industries, where their efforts can be rewarded quickly. These small-scale projects are often simple in concept, easily grasped and thus not easily forgotten. I claim here that the first Mobile AR releases will generate early interest in the technology and entertainment markets, with the effect that press reportage and word-of-mouth behaviour assist Mobile AR’s uptake. I must be careful with my claims here however, since there is no empirical evidence to suggest that this will occur for Mobile AR. Looking at the emergence of previous technologies, however, the Internet and mobile telephony grew rapidly and to massive commercial success thanks to some strong business models and advancements in their own supporting technologies. It is strongly hoped by developers like Gameware and T-Immersion that Mobile AR can enjoy this same rapid lift-off. Both technologies gained prominence once visible in the markets thanks to a market segment called early adopters. This important group gathers their information from specialist magazine sources and word of mouth. Mobile AR developers would do well to recognise the power of this group, perhaps by offering shareware versions of their AR software that encourage a form of viral transmission that exploit text messaging.
Gameware have an interesting technique for the dissemination of their HARVEE software. They share a business interest with a Bluetooth technology firm, which has donated a prototype product the Bluetooth Push Box, which scans for local mobile devices and automatically sends files to users in acceptance. Gameware’s Push Box sends their latest demo to all visitors to their Cambridge office. This same technology could be placed in public places or commercial spaces to offer localised AR advertising, interactive tourist information, or 3D restaurant menus, perhaps.
Gameware, through its Nokia projects and HARVEE development program is well placed to gain exposure on the back of a market which is set to explode as mobile offerings become commercially viable, ‘social’, powerful, multipurpose and newsworthy. Projects like HARVEE are especially interesting in terms of their wide applicability and mass-market appeal. It is its potential as a revolutionary new medium that inspires this very series.