Visual programming of intelligent agents for virtual archaeology

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<ul><li><p>7/28/2019 Visual programming of intelligent agents for virtual archaeology</p><p> 1/4</p><p>Visual programming of intelligent agents for virtualarchaeology</p><p>Undisclosed</p><p>Abstract Historians and archaeologists have used virtual worldsin their research to provide them with a laboratory to testhypothesis based on excavation data, site pictures, historicdocuments and images, and similar elements. Known as virtualarchaeology, this new set of methods to visualise historic sites hasso far focused on depicting the architecture and artefacts foundon the sites. More recently, however, historians andarchaeologists have employed virtual worlds to also study socialinteraction in those sites, thus increasing the level of immersionfor researchers, students, and visitors, but also presenting newchallenges: simulation of behaviour and social interaction</p><p>commonly uses intelligent agents, an area extensively researched,but which requires relatively advanced programming skills whichmight not be universally available to historians and archeologists.Work done for this thesis will attempt to provide them withsimple, visual tools to allow researchers to describe profiles andrules enabling the simulation of social interaction inside heritagesites recreated in virtual worlds using Second Life/OpenSimulator technology.</p><p>Keywords: Virtual archaeology; Second Life; OpenSimulator;visual programming; intelligent agents</p><p>I. INTRODUCTION</p><p>Virtual archaeology is a field of research that employs</p><p>techniques and methods used by historians and archaeologists,using computer-generated models, to visualise culturalartefacts and heritage sites [1]. These days, most of thosemodels are done in 3D and have become increasingly popularas the cost of sufficiently powerful hardware to render 3Dsynthetic environments dropped to affordable levels.</p><p>Historically, this area of computer science focused mostlyon the technology to render 3D artefacts and heritage sites[2].Research focused on realism and immersive interfaces, usuallyusing haptic devices, and the goal was to provide an experienceof the past that was as realist as possible. This captured theattention of the movie and games software industry which wereinterested in the degree of realistic detail provided by thetechnology employed on the models. On the educational side,</p><p>most of the installations were made in museums or similarenvironments, where whole rooms could be dedicated to therequired machinery providing the illusion of walking acrossheritage sites; more light-weight solutions, using portablehelmets and augmented reality glasses, started to appear onsome historical sites, providing additional information tovisitors.</p><p>However, Frisher reports that the focus of those initialattempts was on the spectacularity of the technology, and noton its historical accuracy. Frequently, historians andarcheologists were not part of the research teams, which</p><p>included mostly computer experts, software engineers, and 3Dmodellers. Several decisions were made during the creation ofthe models that were poorly documented (or not at all) and thecriteria were mostly favouring an interesting, quasi-cinematographic experience, regardless of the actual level ofhistorical accuracy of the models. Additionally, the costs were</p><p>prohibitive for most installations, mostly due to the hardwarerequirements, many of which were still experimental</p><p>prototypes, custom-built for a specific type of experience, andnot easily available.</p><p>This lead historians and archaeologists, recognising theimmense potential of 3D computer models for their research, tostart proposing research methodologies focused on thehistorian/archaeologist (one of those methodologies is detailedin the London Charter [3], but others exist). These documentsspecified guidelines for adding documented justifications of allmodelling decisions made during a virtual archaeology project,described metadata types to identify the 3D objects used in the</p><p>project, and suggested methods to keep track of successiverevisions and versions of the project. The adoption of such amethod would allow researchers to validate models as to theirhistoric accuracy, by allowing further researchers to build theirown models based on the documentation provided, andeventually confirm or reject the model independently.</p><p>Thus, current research in virtual archaeology tends to havehistorians and/or archaeologists as project leaders, withtechnically qualified researchers contributing to the projectdevelopment under their guidance. This lead to historicallymore correct models, which, however, might be visually lessattractive.</p><p>The new model is not free of problems. On one hand,historians might not be technologically proficient enough tounderstand how to use and employ appropriate computerhardware and software to model the heritage site [4] or havedifficulties in conveying what they wish to create to thetechnical team, overestimating the capabilities of current-generation hardware and software. Research teams and</p><p>technical teams might be separated, working in isolation ofeach other, and only with difficulty manage to complete aproject that is fulfilling to both and is also historicallyvalidated. Fortunately, such examples abound (Rome Reborn isa typical example of a successful project [5]).</p><p>Since many of those projects might not be so visuallyappealing as the first-generation projects, the movie and gameindustry have been more reluctant to adopt them, preferringinstead to continue to use historically inaccurate models, sincethey have a different audience in mind entertainment andnot necessarily education. This raises the question of how to</p></li><li><p>7/28/2019 Visual programming of intelligent agents for virtual archaeology</p><p> 2/4</p><p>distribute the results of a virtual archaeology project once all3D models have been created; very often, the costs ofdistribution have to be included in the project as well.</p><p>II. VIRTUAL WORLDS</p><p>A. Solving distribution problems, but raising new ones</p><p>Virtual worlds are synthetic computer-generated 3Denvironments used simultaneously by thousands or evenhundreds of thousands of users, each of which represented bytheir avatar, and who can interact, in real time, with thesimulated environment. These allow for the same model to beinstantly visualised by several users sharing the same virtualspace, and are thus appropriate both for entertainment andeducational purposes (e.g. a guided tour to Ancient Rome,which can be visited alone or in a group with or without aguide [6]).</p><p>Among all virtual worlds, Second Life, and its opensource counterpart, OpenSimulator, has gained popularityamong the research community. Second Life has around twentymillion users registered with their avatars, and all the displayedcontent is created by its users. 3D content is created and</p><p>visualised in real-time; no special external software is required,since the open source Second Life Viewer includes all buildingand programming tools to create content, which appearsimmediately for all users in the same scene, without requiringrendering. Content is created collaboratively: several users canwork on the same models at the same time, and each will seeimmediately the results of adding further content. Theunderlying system will provide object persistence by storingcontent on the so-called grid servers, which are hosted by thecompany Linden Lab in the case of the Second Life Grid acollection of several servers running a single, visuallycontiguous virtual world. While creating appealing contentrequires some skill and talent, the creation tools were designedwith amateurs in mind. All this has contributed to itswidespread use as a residential entertainment platform, a</p><p>business tool, an education platform, and as a research andsimulation platform for many different areas; virtualarchaeology neatly fitted in the kind of possible uses forSecond Life.</p><p>When working on a virtual archaeology project, teams canlog in from geographically distinct areas but workcollaboratively on the same virtual site; due to the nature ofimmediate visualisation of the created content, historians canuse Second Life as a research lab: modelling heritage sites</p><p>based on researched documentation and images and deployinga possible virtual reconstruction of the site. Researchers canimmediately validate their assumptions visually and proceed tocorrect them. Changing models or moving it to different places</p><p>is very easy to accomplish even for an unskilled user; bycollaborating with skilled 3D modellers, historians can, in thevirtual world environment, using communication tools likeVoice over IP (VoIP) or simple text chat, instruct technicians to</p><p>position content accurately. This interactive mode of closecollaboration allows several hypothesis about the layout of theheritage site to be quickly evaluated and approve or rejectthem. Simultaneously, while the site is being reconstructed, thearea can be opened to visitors; thus, it is possible todynamically adapt and change the whole site, or start with anarea but expand it gradually, while the site is being activelyvisited. Virtual worlds like Second Life neatly exploit this</p><p>facility to distribute content to a relatively large audience veryeasily; unlike other platforms, it eliminates long preparation</p><p>phases before modelling begins, followed by content actuallygetting modelled using specialised and expensive 3D tools likeMaya, 3DS, Blender, or others; 3D models get rendered (whichusually takes a lot of time); digital video footage is capturedand then edited; and finally, the resulting images are published,</p><p>burned to DVDs, or sent to websites for streaming. Anycorrections required under a more traditional approach take alot of time until a new version is produced and distributed tothe end users. By contrast, using virtual world technologies,heritage sites are immediately available once modelling isfinished, and they can be changed dynamically in real time andadjusted instantly without any further delays.</p><p>Morgan [4] explains how this process even allowshistorians to forfeit the use of specialised 3D modellers;historians and archaeologists might be able to acquire therequired skills to do the modelling themselves. While theresults might not be as visually appealing as the ones produced</p><p>by talented professionals, they will be historically correct, andthe elimination of a further layer of communication with non-historians might lead to faster results.</p><p>B. Virtual archaeology is not only about architecture</p><p>Nevertheless, traditional methods of creating virtualarchaeology projects that lead to video documentaries have oneimportant feature: they show humans (in this case, humanactors) interacting within the environment of a heritage site.Archaeology is not only about architecture and art, but alsoabout the people who populated the site; from an educational</p><p>perspective, it is important to contextualise the architecture andart and show how it has been used by its past inhabitants.</p><p>In virtual worlds, to convey the human dimension, onevalid approach is to hire actors, who, through their avatars, willdemonstrate human interaction within the virtualreconstruction. The problem in this case is that virtual worlds</p><p>are visited 24 hours a day, 7 days a week; staffing a virtualreconstruction full time, around the clock, is often way beyondthe resources of most virtual archaeology projects. A tradeoff isto announce specific events on certain dates, and expectvisitors only to arrive at the specified hour. This, however, willexclude many potential world-wide users who might beinterested in the project but live in timezones that disallowthem to participate at the appointed hours; by contrast, a gameor a video can be played at a convenient hour for all interested</p><p>parties, and repeated as often as the viewer wants.</p><p>A possible solution is to model the behaviour of inhabitantsof the heritage site using intelligent agents.</p><p>III. INTELLIGENT AGENTS IN VIRTUAL ARCHAEOLOGY</p><p>The immediate advantage of using intelligent agents invirtual archaeology projects is that they are always available.They also permit the researchers to model behaviour easily andfit it better to the environment, or even apply the sameapproach to architecture and formulate what-if scenariosabout the use of certain spaces by human inhabitants. Unlike avideo documentary, which usually just presents one possibleway of human interaction with the heritage site, virtual worldsusing intelligent agents to model human behaviour can show awhole range of different behaviours, and allow researchers to</p></li><li><p>7/28/2019 Visual programming of intelligent agents for virtual archaeology</p><p> 3/4</p><p>evaluate them, picking the ones that better reflect the findingsfrom researched data.</p><p>Intelligent agents are also very-well documented and havemany implemented solutions (e.g. Bogdanovych [7]). The</p><p>problem is that they require programming, a skill that mightnot be available to many historians or archaeologists. In thiscase, a common method is to use programming by imitation,where human operators teach intelligent agents by</p><p>demonstrating what they should accomplish (e.g. walk across astreet, carry this object, sit here, turn around, and so forth); thistechnique was employed by Goertzel et al. in Second Life [8].The problem is that simulating human behaviour by carefully</p><p>programming each intelligent agent by imitation takes a lot oftime and can be tedious.</p><p>IV. SCOPE OF THE DOCTORAL THESIS</p><p>To summarise the above issues, a virtual archaeologyproject with scientific accuracy requires having an historian orarchaeologist as a project leader. Better projects will not onlyinclude artefacts and architecture, but propose models ofhuman behaviour interacting with the heritage site; these willalso increase the immersive nature of the project for potential</p><p>visitors or students.The problem is that historians and archaeologists might not</p><p>be technically qualified to do complex programming ofintelligent agents; while some forms of programming byimitation exist, they can be slow, painful, and tedious.Historians can already validate architectural models in alaboratory setting, but the question remains open on how tovalidate models of human behaviour and interaction in thosevery same heritage sites.</p><p>Thus, ultimately, the issue is how to allow historians todevelop those models without requiring them to learn</p><p>programming languages and acquire proficiency in those. Apossible solution might involve developing a new set of simple</p><p>visual tools; but those might be either too simple and notpowerful to replicate the desired behaviour models, or,conversely, they might make the task overwhelmingly difficultfor historians.</p><p>V. PRACTICAL CASES</p><p>In my work at the company Beta Technologies, whichdevelops content and applications for the virtual world ofSecond Life (or on OpenSimulator-based virtual worlds,which, for all purposes, work similarly), I have participated inthree virtual archaeology projects, all of them involving notonly the 3D modelling of a reconstruction of a historical site,</p><p>but a...</p></li></ul>

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