CHAR: An Online Collection and Database of Augmented Reality Apps in Museums and Cultural Heritage Sites
Liron Efrat, University of Toronto, Canada
AbstractThis paper presents the CHAR collection which groups over 100 cultural heritage AR apps and related materials, including apps for museums, art projects, activism, and AR apps for archeological and heritage sites. In this collection, I identify twelve categories of AR application in cultural heritage settings and I use them to classify the projects. In CHAR, entries documenting AR projects can be browsed individually and in groups based on their AR category. These AR categories are indicative of twelve different ways to (re)construct the user experience of cultural heritage content and sites, and they contribute to the field by providing an overarching, medium-specific framework for both the analysis and production of AR apps in cultural settings. After presenting the database and its main functions, this paper will outline two sets of six AR categories and will present key examples from CHAR. The first set includes projects that use AR to expand visitors' interpretation of heritage or museum sites as geographical or architectural locations, and the second set includes projects that use AR to animate and diversify the interpretations of history and heritage. While most researchers have considered AR as a spatial technology, the categories in CHAR demonstrate that AR is both a spatial and a temporal medium. This observation illustrates additional aspects of the perceptual paradigm promoted by cultural heritage AR and, more specifically, it shows how cultural heritage AR can (1) reject the perception of time as a linear chronology, and (2) decentralize the production and interpretations of history and heritage. Accordingly, CHAR becomes a research tool that emphasizes the added value of using AR in the context of cultural heritage. This tool aims to assist scholars, museum professionals, educators, and AR designers and practitioners in the process of analyzing apps and developing new and impactful projects.
Keywords: Augmented Reality, Digital Cultural Heritage, Museum apps, AR apps, Online Databases
CHAR: An Online Collection and Database of Augmented Reality Apps in Museums and Cultural Heritage Sites
Liron Efrat, University of Toronto
“All reality is mixed reality”, Mark Hansen declares in the opening of Bodies in Code (Hansen, 2006). Although this statement may have infinite meanings, Hansen’s interpretation is quite specific: reality is formed through the mixing of bodies with existing technologies. As a result, Hansen explains, our situation is configured by available technologies, their applications, and the ways we employ both. In the vein of Hansen’s technologically-driven phenomenological approach, I examine the user experience of digital cultural heritage apps in light of one of the most influential technological advancements in the past two decades: Augmented Reality (AR). In this paper I introduce CHAR, an online collection of AR apps I developed, which functions as a research tool that focuses on the (re)production of cultural heritage narratives through AR. This tool demonstrates how the visitor experience in cultural heritage sites can be reshaped using different AR applications that practice and constitute different perspectives of historical time, linearity, and narratives.
Frequently associated with the Pokémon GO craze in 2016 and defined as a layering of dynamic digital data over physical space (Azuma, 1997; Milgram, 1994), Augmented Reality (AR) has become a common form of cultural production. Over the past decade AR apps for museums, archives, and cultural heritage sites have become popular among visitors and institutions alike. However, while such a mode of cultural production makes a significant impact on our engagement with cultural heritage and narratives, these AR projects are usually discussed either in isolation or as a part of a larger consideration of the contemporary culture of digital heritage. Although both forms of discourse certainly contribute to our understanding of the social function of such mediated experiences of heritage, CHAR offers another perspective. In this collection, I adopt a comparative and relational approach by gathering AR cultural heritage apps and grouping them into twelve application categories.
Augmented Reality can facilitate different relationships between digital data and material environments, providing rich insights in cultural heritage and museum settings. While still in development, the CHAR collection will ultimately group over 100 cultural heritage AR apps and related materials, including apps for museums, art projects, activism, and AR apps for archeological and heritage sites. In this collection, I identify twelve categories of AR application in cultural heritage settings and I use them to classify the projects. In CHAR, entries documenting AR projects can be browsed individually and in groups based on their AR category. These AR categories are indicative of twelve different ways to (re)construct the user experience of cultural heritage content and sites, and they contribute to the field by providing an overarching, medium-specific framework for both the analysis and production of AR apps in cultural settings.
After presenting the database and its main functions, this paper will discuss the CHAR metadata and inclusion criteria. I will then continue by discussing the methodology and research approaches for the collection’s development, and will outline the two sets of six AR categories and include key examples from CHAR. The first set includes projects that use AR to expand visitors’ interpretation of heritage or museum sites as geographical or architectural locations, and the second set includes projects that use AR to animate and diversify the interpretations of history and heritage. This tool, partly funded by the Ontario Tech University and the Decimal Lab, aims to assist scholars, museum professionals, educators, and AR designers and practitioners in the process of analyzing apps and developing new and impactful projects.
Functionality and Internal Logic of CHAR
The CHAR (Cultural Heritage Augmented Reality) apps collection is housed and is accessible through the Decimal Lab’s archival Platform, Fabric of Digital Life (https://fabricofdigitallife.com/). Created by Andrew Illadis and Isabel Pedersen, Fabric is an online database with a declared goal of capturing “how metadata taxonomies in embodied computing databases indicate context (e.g. a marketing context or an ethical context) and describe ways to track the evolution of the embodied computing industry over time through digital media archiving” (Iliadis and Pedersen 2018; Illadis and Pedersen, 2017). CHAR can be accessed under the browsed collection option, or through the side-bar at the right of the landing page [Figure 1].
As of this writing, CHAR contains 60 main entries and approximately 40 supplementary objects. The main entries in the collection include documentation and metadata of existing and past AR projects in cultural settings. This documentation consists of videos, images, or screen grabs from the apps, which represent the functionality of the User Experience (UX) interface and the mode of interaction facilitated by the app. The supplementary objects include documentation of responses to main entries’ subjects, such as press releases, media coverage, or blog entries. The Sanhedrin Trail app is an example of a main entry in CHAR; the app accompanies the 70km, recently excavated trail, which connects several archeological sites of Jewish settlements from the 2nd Century B.C.E. at the Galil area in Northern Israel. Through the app’s interface, hikers gain access to digital models of archeological reconstructions of the sites and learn about the natural environment of the area. In another example, Ghosts of the Horseshoe app exposes the hidden history of the University of South Carolina, unveiling the slave labor that was employed to build the university campus. Users of Ghosts can listen to recorded testimonials and gain access to many archival materials documenting the campus’ construction while navigating the site. Both of these entries include internal links to supplementary, affiliated entries under the “related object” field.
The Keywords used in the collection serve three roles: technological keywords indicate the type of systems and devices employed by the app, and general keywords are used to connect CHAR’s entries with other objects indexed on Fabric. However, while the main entries in CHAR can be filtered and grouped according to Fabric’s list of keywords, this collection also features a new set of twelve keywords that describe the twelve AR application categories the collection illustrates. These categories appear as clickable keywords in the collection’s description, as well as in each individual entry. When clicking on a category keyword, all the entries belonging to this category will appear, simultaneously demonstrating a connection between separate AR projects and the diversity of practices under a specific type. A more detailed description of CHAR’s categories is provided below.
CHAR’s Category Sets
The entries in CHAR are classified according to twelve original AR application categories that are divided into two sets. The first set includes projects that use AR to expand visitors’ interpretation of heritage or museum sites as geographical or architectural locations. Categories of the first set are Opening Space; Deconstructing Spaces; Controlled Space; Display Objects; Locational Convergence; Compositional Convergence. The second set includes projects that use AR to animate and diversify the interpretations of historical time and heritage. Categories of the second set are Historical Annotation; Revival of Past; Repressed Past; Counterfactual Histories; Future Potentialities; Historical Modelling and Reconstruction. The AR category for each project is briefly explained under the project’s description and would also appear as a keyword; full descriptions and an explanation about the development of these categories have been published elsewhere (Efrat, 2021).
Both category sets are conceived in order to map the different relationships between the material environments and the virtual content AR interfaces facilitate. Accordingly, these categories are indicative of twelve different ways to remodel and retell cultural narratives, and to reshape visitors’ knowledge and experiences through AR. While the first set maps relationships related to the meanings of space and place, the second set maps relationships related to our interpretations and experiences of time and history. An example from the first set is the Stedelijk Museum’s 2010-2013 ARtours project. This three-stage project was conceived and executed by the Dutch museum in order to maintain access and engagement with the institution and its collections while being closed over three years of renovations (Schavemaker, 2011). Allowing users to self-borrow digital replicas of artworks and to engage with art and heritage on diverse public sites, ARtours was, in fact, a way to reconceptualize the museum as an institution that is independent of both its geographical location and its building walls. As Stedelijk’s display left the museum’s gallery halls and expanded into the city, both the museum and its content became imbued with additional cultural meanings. Because the digital content in ARtours aims to diversify the traditional meanings associated with places and heritage objects, this project demonstrates the AR category of Opening Space. In this category, digital content is integrated with actual environments to democratize locations from familiar meanings. Using AR in this way, places are becoming generally open to being inscribed with new perspectives and interpretations.
Examples from the second set include the previously mentioned apps The Sanhedrin Trail and Ghosts of the Horseshoe. Visualizing models of the archeological sites from the 2nd Century B.C.E. in-situ, the digital content in The Sanhedrin Trail describes a virtual past and embeds it within the present experience of heritage in real-time. Therefore, The Sanhedrin Trail app demonstrates the AR category of Historical Modelling and Reconstruction. In this category, digital visualizations of an assumed past are imposed onto a relevant physical location, such as an archeological site. The virtual content in this case does not directly represent indexical archival materials, such as documents or photos, but rather it is a result of processing research materials and thus it reflects an educated assumption about the past in-situ [Figure 2]. In Ghosts of the Horseshoe, the app visualizes a counter-dominant, black narrative whose traces have been almost completely erased from material space. Uncovering suppressed cultural knowledge, the digital content in this case has the potential to completely transform our sense of place and to provide a more holistic understanding of historical causality and the formation of public arenas. Portraying content that has been actively removed from sight and attention, Ghosts of the Horseshoe AR app demands that we make history more inclusive as it demonstrates the AR category of Repressed Past. In this category, digital content is used to enliven and geo-locate actual, repressed narratives. The goal here is to include new narratives as a valid form of heritage and thus to imagine another, virtual but possible, future [Figure 3].
Figure 2: The Sanhedrin Trail Entry, Screen-grab from CHAR
The category sets therefore provide an insight into the added value and the potential usability of AR in cultural heritage settings. Designing and interacting with AR projects, we may want to consider not only how the technology reshapes the ways we interpret material environments and tangible heritage, but also how AR can employ different historical timeframes. AR can thus elucidate the manner in which histories are perceived and can be expanded and multiplied to establish a renewed present experience in a given setting. What AR projects like Ghosts of the Horseshoe ultimately represent is the idea that history should not be conceptualized as one, cohesive and linear development; through AR, many historical narratives can be illustrated, and history itself can be visualized as a multiplicity of voices and stories that validate alternative and intangible heritage by affiliating them with relevant places.
Such multiplicity of historical narratives and timeframes is also reflected in other categories mapped by CHAR, such as Counterfactual Histories. In this category, projects like Mapping Ararat (2014) [Figure 4] are developed to visualize scenarios that were possible but did not actualize, thus posing the question of alternative pasts and futures. Mapping Ararat digitally actualizes an early plan for a prospective Jewish state in New York, which was initiated and patronized by Mordechai Noah in the early nineteenth century (Kaplan, 2013; Kaplan and Shiff, 2016). In the Mapping Ararat app, visitors to Grand Island, NY, are invited to explore the never realized Ararat community, imagining how such a Jewish colony would look had it been developed. The tour contains 24 digital monuments and structures accompanied by audio tracks describing the settings. In this case, the virtual content is geo-located in a site-specific manner to represent events that did not happen, but could have happened. As a result, these projects raise questions of “what if” and trigger visitors’ imagination to contemplate the idea of multiple histories, as well as the formation of their own historical moment.
This is the place to mention that the CHAR categories also expand how AR technologies are normally perceived: while most researchers have considered AR as a primarily spatial technology (Farman, 2014; Cooley, 2017), the categories sets and the examples included in the collection demonstrate that AR is both a spatial and a temporal medium. Understanding digital and spatial technologies as time-based media is supported by the views of scholars such as Nanna Verhoeff (2012) and Paul Virilio (1991) and understanding AR apps this way illustrates additional aspects of the AR perceptual paradigms that can be promoted by cultural heritage AR and utilized by institutions in museum apps. More specifically, the CHAR categories show how cultural heritage AR can (1) reject the perception of history as a single-narrative, linear development, and (2) be employed to decentralize the production and interpretations of history and heritage. Accordingly, CHAR illustrates the potential of AR apps to become inclusive and participatory tools for the production of heritage, and it can also serve as a research tool for institutions and AR practitioners exploring the field.
A Relational and Comparative Approach to Cultural Heritage AR
The projects included in CHAR are grouped based on what I describe as retroactive User Experience (UX) research. This is an analysis of projects and a conceptualization of user engagements conducted post-production, with the purpose of understanding the learning opportunities and the modes of user-environment interactions facilitated by certain app types. In this method, I consider the nature of the information provided (actual, fabricated, etc.), how it is visualized (indexical materials, maps, digital reconstructions, etc.), and what variety of participants actions are enabled. I also consider the extent to which participants’ engagement is pre-scripted and, more importantly, how the information provided by the app relates to its own hosting environment. To create CHAR, I relied on these individual projects’ analyses to further study these variables in a comparative manner. Comparing different projects, I was able to identify common forms of AR application as well as to point towards emerging and innovative modes of AR employment. The category sets in CHAR are therefore the outcome of this mode of comparative research and, correspondingly, they also function as the first overarching framework for the analysis of AR in the context of cultural heritage. The CHAR categories also aim to turn such post-production analysis into useful guidelines that institutions can consider and utilize in the pre-production stages of AR content.
Beyond this, the CHAR categories also build on the recognition that AR is a relational medium. That is, AR’s functionality – as well as its social meanings – are established as a result of relationships between multiple factors, including (but not limited to) digital content, material environments, individual participants, and commissioning bodies. Recalling the examples cited above, it is clear that in every one of its iterations AR always presents us with a set, a mix of elements that are combined through the AR interface. AR mixes the digital data-space with physical environments, combines histories and futures with the present, and infuses participants’ sense of embodied proprioception with dynamic digital output. Correspondingly, the CHAR project focuses less on the reshaping of the material and corporeal domain, or on the autonomy and agency of what is sometimes called “new-media objects” (Manovich, 2001). Instead, it concentrates on the modes of relationships between the two, and on the perceptions and experiences of heritage and heritage sites that these relationships may produce.
My approach to the classification presented at CHAR may also resemble what Museum Studies scholar Ross Parry calls “mediatization” (Parry, 2018). A relatively recent approach to media studies, mediatization seeks to reconcile two other, more traditional approaches to the study of media and tech: media effects (which explores specific media content) and medium theory (which explores the ways in which media interferes with human perception). Mediatization considers both contents analysis and medium engagements as it investigates how given forms of specific media-use emerge, proliferate, and influence socio-cultural relations. Examining the relationships that AR facilitates between its multiple participating factors, as well as the relationships between specific AR content and our perceptions of places and histories, CHAR identifies some of the main areas and strategies through which AR intervenes and reshapes the visitor experience by employing specific AR content. Accordingly, I am also able to reinforce Parry’s observation that “the core of mediatization is found in its social and cultural transformation, not in the technology itself” (Parry, 2018). This, naturally, also requires that we think of technologies in ideological and discursive terms, as they promote cultural concepts and function as agents of social patterns. This view may also accentuate the potential of cultural heritage AR to act as an intersection of multiple perspectives which, as a result, also portrays these apps as tools for social change and as means to reshape, expand, and shed new light on cultural knowledge.
As mentioned earlier, the material indexed in CHAR includes two cases: main entries that document AR projects, and supplementary entries that capture additional material created in response to such projects. While the main entries are the core of CHAR, the supplementary objects make these entries more robust by providing additional context, technological details, and analyses that could not otherwise be indexed. Capturing the responses to cultural heritage AR projects can also help institutions in the process of evaluating and learning from existing examples; thus it can also catalyze creative and innovative employments of AR.
The main entries include diverse metadata fields that aim to describe the apps from both technical and functional perspectives, as well as to provide some context for the projects’ development. In addition to the more traditional information fields such as creators or date, three metadata fields in CHAR are of note: Technology Keywords, Augments, and Description.
The Technology Keywords field indicates the type of tech tools and systems used in every app’s development. It captures the diversity of tech solutions and provides a glimpse into how different tech tools can or have been combined to create different AR apps. Some keywords in the Technology Keywords field, such as GPS or Marker-Based, also testify to the functionality of the app and help to explain what kind of visitor experience is produced.
The Augments field describes what are the human activities, concepts, or senses that are being targeted by the AR app. Thus, it aims to further illustrate the type of user experience facilitated by individual projects. For example, the input in the Augments field for The Sanhedrin Trail entry is Excavating, Discovering, Hiking, Walking, Remembering, and Seeing. The Augments field input for Ghosts of the Horseshoe is Acknowledging, Exposing, Accepting, Connecting, Navigating, and Seeing. Following the formula of CHAR’s housing archival platform Fabric of Digital Life, the Augment field keywords always appear in present progressive verb form. Because these are generic verbs, they also extend beyond the context of the specific entry to elucidate some of the possible modes of the AR HCI interactions.
The Description field in CHAR is composed of three sections: a general description of the AR project, a brief description of the AR application category to which the project belongs, and a Read More section. The first two sections of the description work together to demonstrate how individual AR projects can be seen as a part of larger cultural production trends. Clicking on the category name in a description of a specific entry will show all the entries that have been indexed under that category [Figure 5]. The Read More section of the description includes information and links to supplementary entries which document responses to AR projects. Often, this section also includes a short bibliography of scholarly items, or additional links to primary materials such as authors’ websites. The items cited under the Read More section aim to function as a starting point for conducting further research on individual projects. In many cases, these items will provide information that is not included in CHAR, such as success measures, cultural impact, copyrighted videos and photos, or authors’ reflections and interviews.
Collection Impact and Significance
The CHAR collection, and the typology it outlines and demonstrates, achieve several goals. First, the collection offers an overview of how AR technologies are being used in cultural contexts. It does so by presenting 60 examples showing how AR can construct diverse visitor and user experiences to cultural institutions, heritage objects, and collective narratives. Second, the category sets in CHAR provide an overarching analytical and research framework for AR projects, which can also function as practical guidelines for the development of AR content by cultural institutions and heritage sites. Third, these categories illuminate AR’s potential for reconceptualizing places and histories and, accordingly, it can raise the awareness of both cultural heritage AR designers and commissioning bodies about the diversity of discourses and ideologies that may be promoted by this tool. In other words, since the comparative approach practiced by CHAR presents alternative frameworks for the production of heritage, this typology allows us to engage more creatively and critically with the technology, as well as with the materials presented to us or created by us.
While the categories presented in CHAR are supported by thorough theoretical and UX research I have conducted elsewhere (Efrat, 2020; Efrat and Casimiro, 2021), the format of an online, public collection makes these categories accessible and handy. By including diverse metadata fields and a brief bibliography in each entry, I aspire to turn the engagement with CHAR into a gateway through which further research about the opportunities embedded in digital cultural heritage can be conducted. I also envision that the AR typology may inspire designers and cultural institutions to combine different application categories, and thus to expand and further develop the current use of the technology in museums and other cultural heritage settings.
In this context, it is also worth mentioning that cultural heritage AR projects suffer from a similar problem to that of digital artworks (Grau et.al., 2019): since both the software tools and hardware employed are multiple and develop rapidly, it is challenging to find the appropriate methods and avenues for gathering and documenting such projects. And yet, without proper documentation of the diverse forms of cultural heritage apps and digital museum programming, it becomes challenging to reflect on and effectively utilize the added value of digital technologies. Otherwise put, under these circumstances, learning from others’ experiences may become a complicated and time-consuming task.
CHAR seeks to address this need by collecting, grouping, and displaying connections between separate projects that would perhaps otherwise disappear. Simultaneously mapping and documenting existing modes of museum AR apps, CHAR aims to simplify the exploration process and to encourage the production of innovative and effective application modes. Furthermore: by being included under the umbrella of the Fabric archival platform, CHAR also works to connect cultural heritage AR projects with broader cultural production trends. Although the category keywords are unique to CHAR, this database still shares many keywords with other collections in the Fabric ecosystem which link cultural heritage AR projects with other AR and Extended-Reality (XR) apps. These connections operate to portray a broader picture of the socio-cultural utilization of AR, which may contribute to or trigger new modes of cultural heritage projects.
CHAR was supported by the Decimal Lab and by Dr. Isabel Pedersen, the Director of Digital Life Institute at the Ontario Tech University, who provided insight and expertise that greatly assisted this project. The author also thanks the Department of Art History and the Department of Visual Studies at the University of Toronto for their support, and the collection’s archivist Sharon Caldwell, whose dedication and attention to detail notably improved CHAR.
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