Maxime Leblanc McGill University Bursting the Bubble Theodora Vardouli McGill University

VR Head-Mounted Displays and the Limits of Limitless Worlds

1 ABSTRACT The “bubble" is an oft-used keyword in discussions about (VR) and Virtual 1 Illustration of the HTC Vive Base Environments (VE). Apart from pointing to the growing, yet precarious, rise of these Station's invisible light beam: the Base Station identifies the exact domains in technology markets, the “bubble" is also a prolific metaphor for spatial, expe- location of the Head-Mounted riential, and technical aspects of virtual worlds. Combining material from architectural Display and controllers in a room using infrared light and history and history of computing, this paper situates and critically activates two threads laser emission of the “bubble" metaphor: the bubble as a closed, autonomous system severed from its surroundings, and the bubble as an ubiquitous, limitless environment. Through historical episodes from the development of Head Mounted Displays (HMDs), the paper positions current VR HDMs into a genealogy of miniaturization of actual architectural “bubbles”— from military simulation domes to wearable “micro-environments”—and examines the techniques that support the illusion of these closed, autonomous worlds as limitless and ubiquitous. The paper concludes with the description of a critical design project that exposes the limits of VR's limitless worlds and the role of context (physical, architectural) in both making and breaking the VR bubble.

310 INTRODUCTION Virtual Reality (VR) is a combination of sensors, actua- tors, displays, and computer graphics technologies that co-produce a versimilar artificial environment. In this environment, the users interact with a computer simula- tion through devices mounted on their bodies. One of the earliest mentions of the term “virtual reality” in a comput- er-related context is attributed to American computer scientist and visual artist Jaron Lanier, who in a 1988 inter- view published by the Whole Earth Review defined VR as: "a technology that uses computerized clothing to synthesize shared reality [...] [and which] recreates our relationship with the physical world in a new plane, no more, no less" (Heilbrun 1989). During his work at VPL Research, Lanier was a part of the core team who developed the "Virtual Programming Language" that led to wearable sensing and actuating products intended for consumer use, such as the EyePhone and the Data Suit (Burdea and Coiffet 2003). Currently, some three decades later, bodysuits that enhance virtual experiences with full-body simu- lated sensations are mobilizing research efforts in the VR industry. However, commercial VR hardware is conspicu- ously cephalocentric—placed on and revolving around the head. Head-Mounted Displays (HDMs) are trademarks of a common picture associated with current VR: the wearer, as if blindfolded, stops seeing the "real" world around them and is transported into their individual, virtual, immersive 2 “bubble.” From the outside, the bubble seems impermeable, closed, and inaccessible. From the inside, the bubble feels 2 Exploded diagram of the hard- limitless, expansive, ubiquitous. ware components that compose HTC Vive's Head-Mounted Display HDMs protocol the relationship between these two condi- tions: the hermetic and the ubiquitous. These protocols 3 Henry McCollum’s Stereoscopic are both technical and cultural. In other words, the tech- Television Apparatus (1945) nical configuration of HDMs—the ways in which they link the outside and the inside—can be placed in productive dialogue with particular architectural imaginations of 3 the environment as a “bubble” around an individual, as well as with the specific applications for which HDMs creatively subverts, the dependencies of VR's seemingly were initially developed. limitless worlds on physical, architectural contexts.

In this paper, we compile episodes from the development SIMULATION, OR HOW TO WEAR A DOME of HDMs in the context of military simulations, computer Although electronic HDMs are an essential component of graphics research, and postwar experimental architecture. current VR technologies, wearable devices for interacting These episodes open a reading of HDMs as miniaturized with simulated environments predated the coining of the architectural “bubbles,” from military simulation domes to term "Virtual Reality." In 1945, American inventor Henry J. wearable “micro-environments.” We discuss the cultural De N. McCollum was granted a patent for his Stereoscopic imaginations and technical infrastructures that support Television Apparatus (Figure 3), which he described as “a the understanding of VR as a closed, autonomous world new and improved television apparatus whereby a plurality and, in turn, cast this closed world as limitless and ubiq- of people can simultaneously and with equal facility view an uitous. Building on this critical analysis, we conclude with object which has been transmitted by stereoscopic tele- the framing of a critical design project that highlights, and vision” (McCollum 1945). This apparatus was designed to

311 an actual experience realistically” (Heilig 1962). This simu- lator provided one to four people the illusion of reality using 3D motion pictures that included stereo sound, vibrating seats, and tactile and olfactory feedback though puffs of fragranced air to create a convincing virtual illusion. Training as a philosopher and later as a cinematographer in Italy, Morton understood the importance of his invention for military applications. In his patent description, he stated: “there are increasing demands [...] for ways and means to teach and train individuals without actually subjecting the individuals to possible hazards of particular situations. For example, the armed services must instruct men in 4 the operation and maintenance of extremely complicated and potentially dangerous equipment, and it is desirable to educate the men with the least possible danger to their lives and to possible damage to costly equipment” (Heilig 1962). Indeed, military involvement in the development of HDM-supported simulations as a way to train soldiers led to crucial funding opportunities for researchers, scientists, and engineers. Based on his first invention, Heilig went on to patent other sensory-based cinematic inventions including a more portable version of his Simulator which 5 6 he called the Experience Theatre in 1969.

4 Morton Heilig’s Stereoscopic-television apparatus A seminal project combining computer graphics with for individual use (1957) portable displays came from computer scientist Ivan 5 Heilig’s Sensorama Simulator (1962) Sutherland, alongside his student Bob Sproull. Sutherland 6 Heilig’s Experience Theatre (1969) is mostly well-known for SKETCHPAD, the first interactive computer graphics systems that he developed at MIT in input aerial television signals, split them, and re-transmit the early 1960s. In 1965, having moved to the University them via cathode ray tubes attached to each eye piece. of Utah, Sutherland developed a concept for what he called Earlier stereoscopic devices can be traced back to the the Ultimate Display. This was imagined as a display in 1830s with Charles Wheatstone and David Brewster, who which “a computer would generate graphics of objects that presented similar inventions at the Crystal Palace exhibi- would behave exactly as their real-world counterparts,” tion (Stafford et al. 2001). This apparatus paved the path and the goal was to create simulations with complete towards binocular virtual simulations. Analog stereoscopic sensory responses as a way to enable intuitive and devices provided important contributions to concepts accurate human-machine interaction (Rash et al. 2009). of visual simulation and are at the heart of their digital Three years later, in partnership with Harvard University, counterparts. MIT’s Lincoln Laboratory, and the Defense Advanced Research Projects Agency (DARPA), Sutherland and Sproull By 1957, filmmaker Morton Heilig patented an invention developed the Sword of Damocles. This project, commonly almost identical to McCollum's that delivered TV signals featured in lineages of VR, was in fact an to a binocular head-mounted display. He called this the headset which would display objects/lines in perspec- Stereoscopic-television Apparatus for Individual Use tive according to the user’s head position through space (Figures 4, 5, 6) (Heilig 1957). Building off this inven- (Sutherland 1968). tion, Morton then patented a landmark contribution for HDM-related research: a virtual simulator. The Sensorama Around the same time as Sutherland’s experiments with Simulator (1962) is what is often considered the first DARPA, VR technology made its way to the U.S. Air Force for instance of VR. The intention wasn’t simply to feed televi- simulation purposes. Thomas A. Furness III, founder of the sion signals but, rather, to simulate realistic virtual worlds. Human Interface Technology Lab, designed and built visual According to the patent description this machine would display systems for the cockpits of fighter aircrafts known “stimulate the senses of an individual to simulate as the Super Cockpit, which he spent decades researching

312 Bursting the Bubble Leblanc, Vardouli 7 Dome Trainers imple- mented in the early 1940s

8 TNO ’s Stinger Trainer (1733-1734)

7 8 and perfecting (Steinicke 2016). Furness described this and would oftentimes require repairs to the exterior enve- system as being “based upon several technologies which lope and internal mechanical projection system. A need allow virtual visual, auditory, and tactile worlds to be arose to create lower-cost simulators. Dutch company TNO created for the operator along with an interactive control Physics and Electronics Laboratory, among other research medium which uses eye, head and hand positions and units working on VR technology at that time, developed the speech as control inputs” (Furness 1986). Essentially, Stinger Trainer for ground military troops. As a cost-saving the Super Cockpit was a wearable simulation device that alternative to the construction of these large domes, and recreated flight tests in an immersive way. The system in order to maintain accurate and efficient training envi- would project information such as computer-generated roments, military entities looked toward portable displays 3D maps, forward-looking infrared and radar imagery, such as HDMs, where trainees wore VR headsets and were and avionics data (Encyclopedia Britannica 2018). In other equipped with a stinger mock-up that acted as a joystick words, pilots would fly through data. (Figure 8). Cooperation, an essential part of military prac- tice, required the addition of digital avatars in the VR world Among the many recognized uses for VR technology in the to accurately simulate the presence and position of another way of medical and military training, perhaps the most trainee. TNO’s Stinger Trainer offers one of the clearest notable example was the Stinger trainer developed in the motives for military involvement in VR technology, allowing early-to-mid 1990s. Stingers are Man-Portable Air-Defense military entities to replace and miniaturize massive training Systems (MANPADS) that target low-flying aircraft through bubbles into a more portable head-mounted equivalent: the heat-seeking rockets (Jense & Kuijper 1993). These physical space simulated virtually. MANPADS are complex to operate and require a team of two well-trained soldiers to use. Previously, Stinger training Although the stinger training spaces were physical domes, was performed in large, 20-meter diameter domes with they provided trainees with a metaphorical bubble world in 360-degree projections (Figure 7). Stinger trainees, up to which they could immerse themselves. This bubble-world three at a time, would then cooperate and fire simulated was not only hermetically separated from its exterior rockets at the moving targets on the walls (Jense & Kuijper through the physical surface of the spherical dome, but 1993). In 1941, the film company Technicolor along with also it was a closed world in a conceptual sense. All events inventor Henry Stephens, filed a patent for an anti-air- were computed in advance as part of the simulation and craft Dome Teacher -- a cinematographic apparatus that all actions by the trainees resided within an anticipated projected films of flying aircrafts onto curved surfaces. space of possibilities. Historian of computing Paul Edwards has compellingly juxtaposed closed worlds (autonomous The demand for this technology became widespread, and systems with specific rules that generate and can describe the Royal Air Force built 43 domes across the UK, only six all events in the system) with open worlds characterized of which survive today. Stephens’ invention was ultimately by unpredictability and emergence. He has convincingly implemented in over three hundred locations worldwide connected the military lineages of cybernetics and artificial including Australia, Egypt, India, and Canada (Langham intelligence with a closed world understanding of politics Dome Museum 2019). These domes were costly to make and human subjects. The figure of the dome, as a military

313 of simulation, this section places them in a genealogy of stimulation—arguably a driving force behind the entertain- ment industry’s relentless quest to create hyper-realistic multi-sensory experiences. Looking at HDMs in the context of art and architecture experiments reactivates poten- tially subversive and performative possibilities for current applications of VR, all the while making more palpable the architectural implications of the “immersive bubble.”

In 1969, Coop-Himmelb(l)au proposed the White Suit project (Figure 9). This included an HDM and a bodysuit. Two films were screened in parallel on the HDM: a pornographic film and the sequence of a car accident. Each film was accom- panied with olfactory and tactile feedback. The erotic film presented the wearer with a sweet-smelling perfume and a gentle mechanical caress on the torso, while the acci- dent circulated fresh blood through plastic piping giving off a strong iron smell and the haptic suit would ‘crush’ the user’s kidneys (Coop Himmelblau et al. 2010). Other proj- ects such as The Soul Flipper and Rehab had a similar goal: to create wearable micro-architectures that would exter- nalize the otherwise internal emotions of human beings. The 9 architecture of the body no longer obeyed typical semiotic functionalism.

Although a computer simulation was not used to change a user’s perception, helmets distorted reality to create new spaces. Haus-Rucker-Co's Flyhead (Environment Transformer) helmet (Figures 10, 11) consisted of two translucent hemispherical plastic bulbs which “changed sensory impressions for a limited time in a visual and acoustic way." The project was described as drawing the

10 11 "processes of seeing and hearing [...] out of their habitual 9 Coop Himmelb(l)au’s The White Suit (1969) apathy, separated into their individual functions and 10/11 Haus-Rucker-Co’s Flyhead (Environment Transformer) Helmet (1968) put[ting] together again as special experiences” (Haus- Rucker-Co cited in Ortner-Ortner 2018). Haus-Rucker-Co’s work shows the growing interest in perception modification and simulation during the 60s. Flyhead is a strong example simulation screen, is therefore a productive critical device of how HMDs are reconstructing our understanding of for thinking about the closed world aspects of the immer- what constitutes a physical environment. sive VR bubble. Architectural experiments with bubble-looking HDMs STIMULATION, cannot be severed from Coop- Himmelb(l)au or Haus- OR ARCHITECTURES OF BUBBLES Rucker-Co's work with bubble architecture: pneumatic As Lydia Kallipoliti has most recently demonstrated structures that enveloped the body and cultivated narra- (2018), architects and artists in the postwar period tives of ethereality and change, of potentiality and . took on closed worlds—autonomous artificial environ- Envelopes and volumes move, and the architecture ments— as a site of architectural imagination. HMDs becomes buoyant like air. Pneumatic constructions without were a particularly provocative sub-genre of these exper- supports allow volume transformations by using air as a imentations, with Austrian architects Coop-Himmelb(l) new ‘building material’. Coop Himmelb(l)au, for example, au and Haus-Rucker-Co being notable interlocutors. If believed that the forms generated by the air, working in military applications make us think of HDMs in the context conjunction with projections of color, sounds, and smells,

314 Bursting the Bubble Leblanc, Vardouli influenced the quality of the perception of spaces (Coop Himmelblau et al. 2010).

Bubbles were also exercises in scale. The bubble as a form has the unique ability to enclose the largest volume of air for the smallest surface area (Hutchings, Morgan, Ritore, & Ros 2002). The British architectural group Archigram framed the imagination of bubble architectures as individual micro-environments that could be combined to produce conditions for sociality. Released as part of their printed issues, Archigram's Suitaloon (Figure 12) was described as a suit that provides “all the necessary services" (Cook et al. 1999). The description of Suitaloon reads: “each suit has a plug serving a similar function to the key to your front door. You can plug into your friend and you will both be in one envelope, or you can plug into any envelope, stepping out of your suit which is left clipped on to the outside ready to step into when you leave. The plug 12 also serves as a means of connecting envelopes together to form larger spaces” (Cook et al. 1999).

ENVIRONMENT BUBBLES AND ENVIRONMENTS OF BUBBLES This idea of plugging into someone else’s bubble in order to establish connections can be observed in modern-day virtual reality systems. One can plug in their VR headset (portal to the virtual environment modeled according to the user’s specifications) into their computer and gain access to multiplayer virtual worlds. Applications like VRChat and BigScreen allow multiple users to join in private servers and talk, interact, and even watch movies in a simulated cinema.

13 14 The imagination of micro-bubbles has been predominantly centered on the human head: receiver and processor 12 Archigram’s Suitaloon Comfort For Two (1972) of all senses. In the late 1960s, Austrian media artist 13/14 Walter Pichler’s Protoypes (1967) Walter Pichler produced his famous prototypes of the TV Helmet/Portable Living Room (1967) and Small Room (1967). "Environmental helmets” of this sort were further closed environment that becomes a new expansive and developed by Haus-Rucker-Co and Coop-Himmelb(l)au ubiquitous reality. and Ugo La Pietra (Rouillard 2013). Pichler experimented with these ideas in the works of his Prototypes exhibition This image is not far from contemporary common concep- of 1967, which he co-curated with architect Hans Hollein tions of VR: closed immersive bubbles separated from (Branscome 2015). This move took the idea of minimum the “real” physical space. However, this conception is not dwelling (the smallest space suitable for a human inhabi- entirely accurate. VR takes place: it is constructed through, tant) predominant in architectural conversations since the and can be broken by, physical space. “Real” places interwar period, and further miniaturized it in a wearable make, and can burst, the bubble. Current generation VR device (Figure 13). This miniaturization made the minimum systems, such as the HTC Vive, use optical tracking to dwelling infinitely expansive. The photograph of the wearer enable room-scale geo-localization of a user within space. of one of Pichler’s elaborate prototypes sitting in a derelict External sensors sweep the room with pulsating lasers, room (Figure 14) is telling: One is somewhere, but is really and, through careful calibration between the timing of each elsewhere. The wearer enters a separate, autonomous, pulse and sweep, the system uses simple trigonometry to

315 15 Frames from an experiment performed by the authors which captured views from the HTC Vive’s displays, the anti-collision system (Chaperone), SteamVR, OpenVR and an external depth camera. A basic 30-second simulation was performed in the default SteamVR home and the data was compared with positional data from a real-world 2m x 2m space. The goal was to understand how and what VR sees. find the location of the HMD to within a fraction of a milli- critique the closed world attitude toward VR, we have meter. Given the intrinsic functionality of optical tracking initiated a critical design project that translates virtual systems, the environment in which a user appreciates a obstacles into architectures in the physical world—making simulation becomes an important factor in the functionality the virtual environment become part of the physical of the system. The physical boundary that contains environment. This aligns with a set of approaches that are VR technology is just as much a part of the process of referred to as Augmented Virtuality or . The world-making as the hardware itself. VR simulations particular focus and contribution of this project is placing happen within physical space through a user’s movement Augmented Virtuality approaches in critical dialogue with and interaction. the lineages that we followed in this paper.

Previous iterations of VR tracking included magnetic, The genealogies we have traced here place the VR bubble acoustic, and even mechanical systems; however, these —as it is constructed through HDMs—in architecture: in methods were quickly discontinued due to various ineffi- architectural discourses of micro-bubbles, in architec- ciencies and vulnerabilities. The choice to operate using tural types of simulation domes, and in architectural optical tracking makes specific kinds of spaces more metaphors of closed worlds. We also placed the VR bubble conducive to VR than others: large, dark, and unobstructed more literally in the architectures of the rooms in which the rooms of approximately five meters by five meters. Sunlight, wearer puts on their HDM and navigates the which has the possibility of interfering with optical infrared (Figure 15). systems, therefore, becomes undesirable. Any physical object present in a room becomes a potential obstacle The critical VR project that comes as future work from this which might occlude the laser's path between an external paper uses Augmented Virtuality to make palpable some of sensor and a HMD. the observations that we have made about the relationship of the VR bubble with architecture, physically and discur- CONCLUSION sively. The implementation that we have initiated focuses To prevent the bubble from bursting, VR systems often specifically on the ways in which the architecture of the encourage the removal of any potential obstacle which virtual space can augment the architecture of the physical might interfere with the simulation. The "outside world" is world in unexpected ways. The pilot version of the project seen as undesirable or antagonistic to the verisimilitude will frame questions around the permeability of virtual of the VR illusion. Could we conceive of a bubble that is reality systems and environments in order to develop elastic? Or of a bubble that is permeable? Aspiring to ways of thinking about VR in an architectural context. By

316 Bursting the Bubble Leblanc, Vardouli Furness, Thomas A. 1986. “The Super Cockpit and Its manipulating the bonds formed as a result of the system Human Factors Challenges.” Proceedings of the Human of relationships between the user, the virtual environment, Factors Society Annual Meeting 30(1): 48–52. https://doi. and the physical environment, this project will generate org/10.1177/154193128603000112. questions pertaining to the interplay between virtual and physical space. Heilbrun, Adam. 1989. “Virtual Reality: Interview with Jaron Lanier.” Whole Earth Review. Specifically, through multi-scalar experimentation, we will explore ways in which a virtual environment can Heilig, Morton L. 1960. Stereoscopic-television apparatus leave traces in physical space. The project involves the for individual use. United States US2955156A, filed May design and making of a physical and a virtual installation 24, 1957, and issued October 4, 1960. Accessed August 11, consisting of geometric objects (points, lines, planes, and 2019. https://patents.google.com/patent/US2955156A/ volumes). The relationship of the configuration of phys- en?inventor=heilig&after=publication:19600101&sort=old. ical and virtual objects will be defined by specific rules of subtraction, supplementation, reversal, ultimately each a Hutchings, Michael, Frank Morgan, Manuel Ritore, and Antonio distorted mirror image of the other. We are in the process Ros. 2002. “Proof of the Double Bubble Conjecture.” The Annals of of designing and implementing a custom haptic feedback Mathematics 155(2): 459. https://doi.org/10.2307/3062123. device that vibrates when it encounters a virtual object. Participants in the project will first navigate the VR instal- Jense, G.J., and F. Kuijper. 1993. “Virtual Environments for lation wearing an HDM. Then, without the HDM and only Advanced Trainers and Simulators,” Proceedings International carrying a custom haptic device, they will move within the Training Equipment Conference and Exhibition - ITEC. London, UK, physical installation while "sensing" virtual objects: remem- 49-57. bering and actively interacting with virtual "ghost" objects. We will explore a set of new spatial typologies that emerge Kallipoliti, Lydia. 2018. The Architecture of Closed Worlds: Or, What through the layering of a physical space with virtual traces, Is the Power of Shit? Zürich: Lars Müller Publishers. and examine ways in which the in-between of physical and virtual architecture can become a locus of creative Langham Dome Museum. 2019. “The Inventor of the Dome imagination. The critical histories we have presented in this Teacher.” Langham Dome. Accessed August 11, 2019. https:// paper become a launching pad for a critical design instal- langhamdome.org/about-raf-langham/the-dome-dome-training/ lation that instigates thinking about the immersive “bubble,” the-inventor-of-the-dome-teacher/. and turns the limits of VR's limitless worlds into a site for creative action in architectural design. McCollum, Henry. 1945. Stereoscopic television apparatus. United States US2388170A, filed April 15, 1943, and issued October 30, 1945. Accessed August 11, 2019. https://patents.google.com/ REFERENCES patent/US2388170/en?oq=7%2c283%2c308. Branscome, Eva. 2015. “Triptych for an Ideal Museum: Hollein, Beuys and Cladders.” AA Files, 71: 92–103. Ortner-Ortner. 2018. “Environment Transformer, 1968.” Accessed August 11, 2019. https://www.ortner-ortner.com/en/ Burdea, Grigore, and Philippe. Coiffet. 2003. Virtual Reality haus-rucker-co. Technology. 2nd ed. 1 (xvi, 444 pages) : illustrations vols. Hoboken, N.J.: J. Wiley-Interscience. Rash, Clarence E., Michael B. Russo, Tomasz R. Letowski, and Elmar T. Schmeisser. 2009. “Helmet-Mounted Displays: Sensation, Cook, Peter, Michael Webb, Warren Chalk, Dennis Crompton, David Perception and Cognition Issues.” Army Aeromedical Research Greene, and Ron Herron, eds. 1999. Archigram. Rev. ed. New York: Lab Fort Rucker Alabama. Defense Technical Information Center. Princeton Architectural Press. Accessed August 11, 2019. https://apps.dtic.mil/docs/citations/ ADA522022. Coop Himmelblau, Peter Gössel, and Michael Mönninger. 2010. Coop Himmelb(l)Au: Complete Works 1968-2010. Köln: Taschen.

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317 Rouillard, Dominique. 2004. Superarchitecture: Le Futur de Theodora Vardouli is Assistant Professor at the Peter Guo-hua l’architecture, 1950-1970. 1st ed. Librairie de l’architecture et de Fu School of Architecture, McGill University. Vardouli's research La Ville. Paris: Editions de la Villette. examines histories and cultures of algorithmic techniques for describing, generating, and simulating architectural form and Sadler, Simon. 2005. Archigram: Architecture without Architecture. performance. She is co-editor of Computer Architectures: Cambridge, Mass: MIT Press. Constructing the Common Ground (Routledge 2019) .

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IMAGE CREDITS Figures 3, 4, 5, 6: Henry McCollum and Morton Heilig patent images available in the public domain (McCollum 1945, Heilig 1960, see references) Figures 7, 8: © 1993 G.J. Jense and F. Kuijper Figure 9: © 1969 Coop Himmelb(l)au Figure 10: © 1968 Ben Rose Figure 11: © 1968 Zamp Kelp, Ortner, Pinter, Haus-Rucker-Co. Figure 12: © 1966-1998 Michael Webb Figure 13: © 1967 Werner Kaligofsky Figure 14: © 1967 Walter Pichler

All other drawings and images by the authors.

318 Bursting the Bubble Leblanc, Vardouli