This paper surveys the field of augmented reality AR, in which 3D virtual objects are integrated into a 3D real environment in real time. It describes the medical, manufacturing, visualization, path planning, entertainment, and military applications that have been explored. This paper describes the characteristics of augmented reality systems, including a detailed discussion of the tradeoffs between optical and video blending approaches. Registration and sensing errors are two of the biggest problems in building effective augmented reality systems, so this paper summarizes current efforts to overcome these problems. Future directions and areas requiring further research are discussed. This survey provides a starting point for anyone interested in researching or using augmented reality.

/pdf/a-survey-of-augmented-reality-17irtaxt7z.pdf

A survey of augmented reality

In 1997, Azuma published a survey on augmented reality (AR). Our goal is to complement, rather than replace, the original survey by presenting representative examples of the new advances. We refer one to the original survey for descriptions of potential applications (such as medical visualization, maintenance and repair of complex equipment, annotation, and path planning); summaries of AR system characteristics (such as the advantages and disadvantages of optical and video approaches to blending virtual and real, problems in display focus and contrast, and system portability); and an introduction to the crucial problem of registration, including sources of registration error and error-reduction strategies.

https://www.cc.gatech.edu/~blair/papers/ARsurveyCGA.pdf

Recent advances in augmented reality

We present a system for interactively browsing and exploring large unstructured collections of photographs of a scene using a novel 3D interface. Our system consists of an image-based modeling front end that automatically computes the viewpoint of each photograph as well as a sparse 3D model of the scene and image to model correspondences. Our photo explorer uses image-based rendering techniques to smoothly transition between photographs, while also enabling full 3D navigation and exploration of the set of images and world geometry, along with auxiliary information such as overhead maps. Our system also makes it easy to construct photo tours of scenic or historic locations, and to annotate image details, which are automatically transferred to other relevant images. We demonstrate our system on several large personal photo collections as well as images gathered from Internet photo sharing sites.

Photo tourism: exploring photo collections in 3D

Computing devices and applications are now used beyond the desktop, in diverse environments, and this trend toward ubiquitous computing is accelerating. One challenge that remains in this emerging research field is the ability to enhance the behavior of any application by informing it of the context of its use. By context, we refer to any information that characterizes a situation related to the interaction between humans, applications, and the surrounding environment. Context-aware applications promise richer and easier interaction, but the current state of research in this field is still far removed from that vision. This is due to 3 main problems: (a) the notion of context is still ill defined, (b) there is a lack of conceptual models and methods to help drive the design of context-aware applications, and (c) no tools are available to jump-start the development of context-aware applications. In this anchor article, we address these 3 problems in turn. We first define context, identify categories of contextual information, and characterize context-aware application behavior. Though the full impact of context-aware computing requires understanding very subtle and high-level notions of context, we are focusing our efforts on the pieces of context that can be inferred automatically from sensors in a physical environment. We then present a conceptual framework that separates the acquisition and representation of context from the delivery and reaction to context by a context-aware application. We have built a toolkit, the Context Toolkit, that instantiates this conceptual framework and supports the rapid development of a rich space of context-aware applications. We illustrate the usefulness of the conceptual framework by describing a number of context-aware applications that have been prototyped using the Context Toolkit. We also demonstrate how such a framework can support the investigation of important research challenges in the area of context-aware computing.

/pdf/a-conceptual-framework-and-a-toolkit-for-supporting-the-3ct19ji2mn.pdf

A conceptual framework and a toolkit for supporting the rapid prototyping of context-aware applications

There are billions of photographs on the Internet, comprising the largest and most diverse photo collection ever assembled. How can computer vision researchers exploit this imagery? This paper explores this question from the standpoint of 3D scene modeling and visualization. We present structure-from-motion and image-based rendering algorithms that operate on hundreds of images downloaded as a result of keyword-based image search queries like "Notre Dame" or "Trevi Fountain." This approach, which we call Photo Tourism, has enabled reconstructions of numerous well-known world sites. This paper presents these algorithms and results as a first step towards 3D modeling of the world's well-photographed sites, cities, and landscapes from Internet imagery, and discusses key open problems and challenges for the research community.

/pdf/modeling-the-world-from-internet-photo-collections-2xqc3i51z3.pdf

Modeling the World from Internet Photo Collections

We describe a prototype system that combines together the overlaid 3D graphics of augmented reality with the untethered freedom of mobile computing The goal is to explore how these two technologies might together make possible wearable computer systems that can support users in their everyday interactions with the world We introduce an application that presents information about our university's campus, using a head-tracked, see-through, head-worn, 3D display, and an untracked, opaque, handheld, 2D display with stylus and trackpad We provide an illustrated explanation of how our prototype is used, and describe our rationale behind designing its software infrastructure and selecting the hardware on which it runs

/pdf/a-touring-machine-prototyping-3d-mobile-augmented-reality-1ierdwk1q6.pdf

A touring machine: prototyping 3D mobile augmented reality systems for exploring the urban environment

We present our preliminary work in developing augmented reality systems to improve methods for the construction, inspection, and renovation of architectural structures. Augmented reality systems add virtual computer-generated material to the surrounding physical world. Our augmented reality systems use see-through headworn displays to overlay graphics and sounds on a person’s naturally occurring vision and hearing. As the person moves about, the position and orientation of his or her head is tracked, allowing the overlaid material to remain tied to the physical world. We describe an experimental augmented reality system that shows the location of columns behind a finished wall, the location of re-bars inside one of the columns, and a structural analysis of the column. We also discuss our preliminary work in developing an augmented reality system for improving the construction of spaceframes. Potential uses of more advanced augmented reality systems are presented.

https://www.cc.gatech.edu/~blair/papers/asce.pdf

Augmented Reality in Architectural Construction, Inspection, and Renovation

SUMMARY—CONCLUSIONS The TMD implementation described in this paperdemonstrates their successful use in substantially reducingthe vibrations of an existing composite floor system. Thecritical reasons for the success of the system are: itstunability, which helped ensure that the theoreticallypredicted performance could be approximated by the actualas-built system; and the cost of the system, which was aboutan order of magnitude less than the cost of recommendedstructural corrective measures.Although the methods used to analyze the case-studyfloor system and design its TMDs are very general, and canbe applied in principle to many composite floor systems, theeffective use of TMDs in structures with higher dampingvalues and lower maximum floor displacements may provetroublesome. It has been claimed that it is generally difficultto make TMDs useful in structures with high naturaldamping. The adjustable viscous dashpots used in this case-study perform marginally at small strokes, suggesting theywould not perform adequately in floors whose amplitudes aresmall. However, other types of damping, which are fieldtunable and

Application of Tuned Mass Dampers To Control Vibrations of Composite Floor Systems

We provide an overview of the early stages of three related research projects whose goals are to exploit augmented reality, virtual worlds, and artificial intelligence to explore relationships between perceived architectural space and the structural systems that support it. In one project, we use a see-through head-mounted display to overlay a graphic representation of a building's structural systems on the user's view of a room within the building. This overlaid virtual world shows the out-lines of the concrete joists, beams, and columns surrounding the room, as well as the reinforcing steel inside them, and includes displays from a commercially available structural analysis program. In a related project, the structural view is exposed by varying the opacity of room finishes and concrete in a 3D model of the room and surrounding structure rendered on a conventional CRT. We also describe a hypermedia database, currently under construction, depicting major, twentieth-century American buildings. The interactive, multidisciplinary elements of the database-including structural and thermal analyses, free body diagrams which show how forces are resisted by portions of a structure under various loading conditions, facsimiles of construction documents, and critical essays-are bound together and made available over the World-Wide Web. Finally, we discuss the relationships among all these projects, and their potential applications to teaching architecture students and to construction, assembly, and repair of complex structures.

Architectural anatomy

In this state-of-the-art overview, the author describes the influence of Japan's largest design and construction firms on the industry at large. Using pertinent case studies, he outlines the firms' technological capabilities, as well as their research and development activities. Chapters cover the effect of recent macro-economic changes to the Japanese economy and the building design and construction industry's relationship to Japan's higher education system and government.

Anthony C. Webster

Papers

A touring machine: prototyping 3D mobile augmented reality systems for exploring the urban environment

Augmented Reality in Architectural Construction, Inspection, and Renovation

Application of Tuned Mass Dampers To Control Vibrations of Composite Floor Systems

Architectural anatomy

Technological Advance in Japanese Building Design and Construction