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Showing papers on "Augmented reality published in 2003"


Proceedings ArticleDOI
05 Apr 2003
TL;DR: Results indicate that overlaying 3D instructions on the actual work pieces reduced the error rate for an assembly task by 82%, particularly diminishing cumulative errors - errors due to previous assembly mistakes.
Abstract: Although there has been much speculation about the potential of Augmented Reality (AR), there are very few empirical studies about its effectiveness. This paper describes an experiment that tested the relative effectiveness of AR instructions in an assembly task. Task information was displayed in user's field of view and registered with the workspace as 3D objects to explicitly demonstrate the exact execution of a procedure step. Three instructional media were compared with the AR system: a printed manual, computer assisted instruction (CAI) using a monitor-based display, and CAI utilizing a head-mounted display. Results indicate that overlaying 3D instructions on the actual work pieces reduced the error rate for an assembly task by 82%, particularly diminishing cumulative errors - errors due to previous assembly mistakes. Measurement of mental effort indicated decreased mental effort in the AR condition, suggesting some of the mental calculation of the assembly task is offloaded to the system.

554 citations


Journal ArticleDOI
TL;DR: Anecdotal evidence supports the claim that Construct3D is easy to learn, encourages experimentation with geometric constructions and improves spatial skills, and the system for the improvement of spatial abilities and maximization of transfer of learning.

493 citations


Book ChapterDOI
15 Apr 2003
TL;DR: Some important issues in choosing the set of gestures for the interface from a user-centred view such as the learning rate, ergonomics, and intuition are presented and a procedure is proposed which includes those issues in the selection of gestures.
Abstract: Many disciplines of multimedia and communication go towards ubiquitous computing and hand-free- and no-touch interaction with computers. Application domains in this direction involve virtual reality, augmented reality, wearable computing, and smart spaces, where gesturing is a possible method of interaction. This paper presents some important issues in choosing the set of gestures for the interface from a user-centred view such as the learning rate, ergonomics, and intuition. A procedure is proposed which includes those issues in the selection of gestures, and to test the resulting set of gestures. The procedure is tested and demonstrated on an example application with a small test group. The procedure is concluded to be useful for finding a basis for the choice of gestures. The importance of tailoring the gesture vocabulary for the user group was also shown.

394 citations


Proceedings ArticleDOI
21 Oct 2003
TL;DR: This paper describes the first stand-alone Augmented Reality system with self-tracking running on an unmodified personal digital assistant (PDA) with a commercial camera and introduces an optional client/server architecture that is based on wireless networking and is able to dynamically and transparently offload the tracking task in order toprovide better performance in select areas.
Abstract: In this paper we describe the first stand-alone AugmentedReality (AR) system with self-tracking running on anunmodified personal digital assistant (PDA) with acommercial camera. The project exploits the readyavailability of consumer devices with a minimal need forinfrastructure. The application provides the user with athree-dimensional augmented view of the environment.Our system achieves good overlay registration accuracyby using a popular marker-based tracking toolkit(ARToolKit), which runs directly on the PDA. Weintroduce an optional client/server architecture that isbased on wireless networking and is able to dynamicallyand transparently offload the tracking task in order toprovide better performance in select areas. Thehardware/software framework is modular and can beeasily combined with many elements of an existing ARframework. As a demonstration of the effectiveness, wepresent a 3D navigation application that guides a userthrough an unknown building to a chosen location.

385 citations


Proceedings ArticleDOI
05 May 2003
TL;DR: This paper shows that automated dynamic repartitioning of mobile applications can be reconciled with the need to exploit application-specific knowledge and presents the design of a tactics-based remote execution system, Chroma, that performs comparably to a runtime system that makes perfect partitioning decisions.
Abstract: Remote execution can transform the puniest mobile device into a computing giant able to run resource-intensive applications such as natural language translation, speech recognition, face recognition, and augmented reality. However, easily partitioning these applications for remote execution while retaining application-specific information has proven to be a difficult challenge. In this paper, we show that automated dynamic repartitioning of mobile applications can be reconciled with the need to exploit application-specific knowledge. We show that the useful knowledge about an application relevant to remote execution can be captured in a compact declarative form called tactics. Tactics capture the full range of meaningful partitions of an application and are very small relative to code size. We present the design of a tactics-based remote execution system, Chroma, that performs comparably to a runtime system that makes perfect partitioning decisions. Furthermore, we show that Chroma can automatically use extra resources in an over-provisioned environment to improve application performance.

287 citations


Proceedings ArticleDOI
02 Nov 2003
TL;DR: This paper formalizes its underlying mathematical framework and detailing three augmented Widgets constructed via this framework: CoCylinder, Magnifier, and CoCube, which promote intuitive ways of selecting, examining, and sharing synthetic objects, and retrieving associated documentary text.
Abstract: We have previously developed a collaborative infrastructure called SCAPE - an acronym for Stereoscopic Collaboration in Augmented and Projective Environments - that integrates the traditionally separate paradigms of virtual and augmented reality. In this paper, we extend SCAPE by formalizing its underlying mathematical framework and detailing three augmented Widgets constructed via this framework: CoCylinder, Magnifier, and CoCube. These devices promote intuitive ways of selecting, examining, and sharing synthetic objects, and retrieving associated documentary text. Finally we present a testbed application to showcase SCAPE's capabilities for interaction in large, augmented virtual environments.

258 citations


Proceedings ArticleDOI
07 Oct 2003
TL;DR: A real-time, robust and efficient 3D model-based tracking algorithm is proposed for a 'video see through' monocular vision system, combining local position uncertainty and global pose uncertainty in an efficient and accurate way by propagating uncertainty.
Abstract: Augmented reality has now progressed to the point where real-time applications are required and being considered. At the same time it is important that synthetic elements are rendered and aligned in the scene in an accurate and visually acceptable way. In order to address these issues a real-time, robust and efficient 3D model-based tracking algorithm is proposed for a 'video see through' monocular vision system. The tracking of objects in the scene amounts to calculating the pose between the camera and the objects. Virtual objects can then be projected into the scene using the pose. Here, non-linear pose computation is formulated by means of a virtual visual servoing approach. In this context, the derivation of point-to-curve interaction matrices is given for different features including lines, circles, cylinders and spheres. A local moving edge tracker is used in order to provide real-time tracking of points normal to the object contours. A method is proposed for combining local position uncertainty and global pose uncertainty in an efficient and accurate way by propagating uncertainty. Robustness is obtained by integrating an M-estimator into the visual control law via an iteratively re-weighted least squares implementation. The method presented in this paper has been validated on several complex image sequences including outdoor environments. Results show the method to be robust to occlusion, changes in illumination and mistracking.

224 citations


Proceedings ArticleDOI
05 Nov 2003
TL;DR: An approach to 3D multimodal interaction in immersive augmented and virtual reality environments that accounts for the uncertain nature of the information sources and fuses symbolic and statistical information from a set of 3D gesture, spoken language, and referential agents is described.
Abstract: We describe an approach to 3D multimodal interaction in immersive augmented and virtual reality environments that accounts for the uncertain nature of the information sources. The resulting multimodal system fuses symbolic and statistical information from a set of 3D gesture, spoken language, and referential agents. The referential agents employ visible or invisible volumes that can be attached to 3D trackers in the environment, and which use a time-stamped history of the objects that intersect them to derive statistics for ranking potential referents. We discuss the means by which the system supports mutual disambiguation of these modalities and information sources, and show through a user study how mutual disambiguation accounts for over 45% of the successful 3D multimodal interpretations. An accompanying video demonstrates the system in action.

206 citations


Proceedings Article
01 Jan 2003
TL;DR: An AR system for training and assisting in maintaining equipment in industrial context, which superimposes the augmentations in the view of the user and a scenario-based concept, which takes users step by step through training or maintenance tasks is described.
Abstract: Complex Assembly and Maintenance tasks in industrial environments are excellent domains for Augmented Reality (AR) applications. The need for good training and the access to large amounts of documentation are conditions making the use of AR techniques most promising. The basic idea of Augmented Reality is to bring additional information as seamlessly as possible into the view of a user. In this paper an AR system for training and assisting in maintaining equipment in industrial context is presented. The key hardware features of the system are an optical see-through Head Mounted Display, which superimposes the augmentations in the view of the user; the tracking system, which gives the system the poses of user and equipment; and a special stand for the installation of the whole application. Aspects of the usage of an infrared optical tracking system and the calibration procedures needed for good results of the virtual overlays are discussed. Finally a scenario-based concept, which takes users step by step through training or maintenance tasks, is described.

202 citations


Proceedings ArticleDOI
07 Oct 2003
TL;DR: A method of personal positioning for a wearable augmented reality (AR) system that allows a user to freely move around indoors and outdoors based on sensor fusion of estimates for relative displacement caused by human walking locomotion and estimates for absolute position and orientation within a Kalman filtering framework.
Abstract: In this paper, we propose a method of personal positioning for a wearable augmented reality (AR) system that allows a user to freely move around indoors and outdoors. The user is equipped with self-contained sensors, a wearable camera, an inertial head tracker and display. The method is based on sensor fusion of estimates for relative displacement caused by human walking locomotion and estimates for absolute position and orientation within a Kalman filtering framework. The former is based on intensive analysis of human walking behavior using self-contained sensors. The latter is based on image matching of video frames from a wearable camera with an image database that was prepared beforehand.

199 citations


Patent
31 Mar 2003
TL;DR: In this article, an augmented reality navigation aid is used to overlay relevant computer-generated images, which are anchored to real-world locations of hazards, onto one or more users' field of view.
Abstract: Method and apparatus are presented for prioritizing and assessing navigation data using an Augmented Reality navigation aid. Navigators are often placed in treacherous, unfamiliar, or low-visibility situations. An augmented reality navigation aid is used to overlay relevant computer-generated images, which are anchored to real-world locations of hazards, onto one or more users' field of view. Areas of safe passage for transportation platforms such as ships, land vehicles, and aircraft can be displayed via computer-generated imagery or inferred from various attributes of the computer-generated display. The invention is applicable to waterway navigation, land navigation, and to aircraft navigation (for aircraft approaching runways or terrain in low visibility situations). A waterway embodiment of the invention is called WARN™, or Waterway Augmented Reality Navigation™. A method is presented for visualization of hazards which pose a serious threat to those in the immediate vicinity. Such hazards include, but are not limited to, fire, smoke, radiation, and invisible gasses. The method utilizes augmented reality, which is defined as the mixing of real world imagery with computer-generated graphical elements. Computer-generated three-dimensional representations of hazards can be used in training and operations of emergency first responders and others. The representations can be used to show the locations and actions of a variety of dangers, real or computer-generated, perceived or not perceived, in training or operations settings. The representations, which may be graphic, iconic, or textual, are overlaid onto a view of the user's real world, thus providing a reality augmented with computer-generated hazards. A user can then implement procedures (training and operational) appropriate to the hazard at hand. A method is presented which uses Augmented Reality for visualization of text and other messages sent to an EFR by an incident commander. The messages are transmitted by the incident commander via a computer at the scene to an EFR/trainee in an operational or training scenario. Messages to an EFR/trainee, including (but not limited to) iconic representation of hazards, victims, structural data, environmental conditions, and exit directions/locations, are superimposed right onto an EFR/trainee's view of the real emergency/fire and structural surroundings. The primary intended applications are for improved safety for the EFR, and improved EFR-incident commander communications both on-scene and in training scenarios.

Patent
18 Sep 2003
TL;DR: In this article, an augmented reality system consisting of a pattern of fiducials disposed on an object surface, a computer having a processor and a memory, a user interface for receiving input and presenting augmented reality output to a user, and a tracker for detecting the pattern is presented.
Abstract: A tracker system for determining the relative position between a sensor and an object surface, generally comprising a sensor or sensors for detecting a pattern of fiducials disposed on an object surface and a processor connected to the at least one sensor. An augmented reality system generally comprising a pattern of fiducials disposed on an object surface, a computer having a processor and a memory, a user interface for receiving input and presenting augmented reality output to a user, and a tracker for detecting the pattern of fiducials. A method for tracking the position and orientation of an object generally comprising the steps of scanning across an object to detect fiducials and form video runs, clumping video runs to detect a pattern of fiducials, acquiring estimated values for a set of tracking parameters by comparing a detected pattern of fiducials to a reference pattern of fiducials, and iterating the estimated values for the set of tracking parameters until the detected pattern of fiducials match the reference pattern of fiducials to within a desired convergence. A method for augmenting reality generally comprising the steps of disposing a pattern of fiducials on an object surface, tracking the position and orientation of the object, retrieving and processing virtual information stored in a computer memory according to the position and orientation of the object and presenting the virtual information with real information to a user in near real time.

Proceedings ArticleDOI
07 Oct 2003
TL;DR: Moves of objective readability from the user study demonstrated that in practice, human subjects were able to read labels fastest with the algorithms that most quickly prevented overlap, even if placement wasn't ideal.
Abstract: View management, a relatively new area of research in Augmented Reality (AR) applications, is about the spatial layout of 2D virtual annotations in the view plane. This paper represents the first study in an actual AR application of a specific view management task: evaluating the placement of 2D virtual labels that identify information about real counterparts. Here, we objectively evaluated four different placement algorithms, including a novel algorithm for placement based on identifying existing clusters. The evaluation included both a statistical analysis of traditional metrics (e.g. counting overlaps) and an empirical user study guided by principles from human cognition. The numerical analysis of the three real-time algorithms revealed that our new cluster-based method recorded the best average placement accuracy while requiring only relatively moderate computation time. Measures of objective readability from the user study demonstrated that in practice, human subjects were able to read labels fastest with the algorithms that most quickly prevented overlap, even if placement wasn't ideal.

01 Jan 2003
TL;DR: A 3-tier architecture to manage a common data model for a set of applications is developed that is inspired by current Internet application frameworks and consists of a central storage layer using acommon data model, a transformation layer responsible for filtering and adapting the data to the requirements of a particular applications on request, and finally of the applications itself.
Abstract: Augmented reality (AR) can provide an excellent user interface for visualization in a mobile computing application. The user’s view is augmented with location based information at the correct spatial location, thus providing an intuitive way of presenting such information. In this work we demonstrate the use of AR for collaborative navigation and information browsing tasks in an urban environment. A navigation function allows one or more users to roam through a city and guides them to selected destinations. Information browsing presents users with information about objects in their surrounding. Both functions feature support for collaboration. The developed system does not only concentrate on the user interface aspects but also provides a scalable infrastructure to support mobile applications. To this end we developed a 3-tier architecture to manage a common data model for a set of applications. It is inspired by current Internet application frameworks and consists of a central storage layer using a common data model, a transformation layer responsible for filtering and adapting the data to the requirements of a particular applications on request, and finally of the applications itself.

Patent
23 Dec 2003
TL;DR: In this article, an augmented reality system consisting of a camera (19) for capturing an image, the camera being movably locatee at a local site, a registering unit (9), generating graphics and registering the generated graphics to the image from the camera, to provide a composite augmented reality image, a display device (5) located at a remote site, physically separated from the local site and a communication link (1), for communication of information between the local and the remote sites, and a specifying unit (7), for specification of a position and an orientation in the remote site
Abstract: An augmented reality system comprising: a camera (19) for capturing an image, the camera being movably locatee at a local site, a registering unit (9), generating graphics and registering the generated graphics to the image from the camera, to provide a composite augmented reality image, a display device (5) located at a remote site, physically separated from the local site, for displaying a view comprising the composite augmented reality image, and a communication link (1), for communication of information between the local and the remote site, and a specifying unit (7), for specification of a position and an orientation in the remote site. The registering unit is adapted for registering the generated graphical representation to the image in dependence of the specified position and orientation, and the camera is arranged such that its position and orientation is dependent on the specified position and orientation.

Proceedings ArticleDOI
07 Oct 2003
TL;DR: A fully automated approach to camera registration for augmented reality systems that relies on purely passive vision techniques to solve the initialization and real-time tracking problems, given a rough CAD model of parts of the real scene.
Abstract: We present a fully automated approach to camera registration for augmented reality systems. It relies on purely passive vision techniques to solve the initialization and real-time tracking problems, given a rough CAD model of parts of the real scene. It does not require a controlled environment, for example placing markers. It handles arbitrarily complex models, occlusions, large camera displacements and drastic aspect changes. This is made possible by two major contributions: the first one is a fast recognition method that detects the known part of the scene, registers the camera with respect to it, and initializes a real-time tracker, which is the second contribution. Our tracker eliminates drift and jitter by merging the information from preceding frames in a traditional recursive tracking fashion with that of a very limited number of key-frames created off-line. In the rare instances where it fails, for example because of large occlusion, it detects the failure and reinvokes the initialization procedure. We present experimental results on several different kinds of objects and scenes.

Proceedings ArticleDOI
07 Oct 2003
TL;DR: The goal is to provide a powerful, flexible and easy-to-use authoring wizard for assembly experts, allowing them to author their new assembly instructor for hierarchical structures, which minimizes the costs for the creation of new mixed reality assembly instructors.
Abstract: Mixed reality is a very useful and powerful instrument for the visualization of processes, including the assembly process. A Mixed Reality based step-by-step furniture assembly application is introduced. On the one hand context related actions are given to the user to install elements. On the other hand an intuitive way for authors to create new MR based assembly instructions is provided. Our goal is to provide a powerful, flexible and easy-to-use authoring wizard for assembly experts, allowing them to author their new assembly instructor for hierarchical structures. This minimizes the costs for the creation of new mixed reality assembly instructors.

Book ChapterDOI
15 Apr 2003
TL;DR: In this article, the authors present a collection of algorithms and related software modules for the EyesWeb open architecture (freely available from www.eyesweb.org), which are used in real scenarios and applications, mainly in the fields of performing arts, therapy and rehabilitation, museum interactive installations, and other immersive augmented reality and cooperative virtual environment applications.
Abstract: This paper presents some results of a research work concerning algorithms and computational models for real-time analysis of expressive gesture in full-body human movement. As a main concrete result of our research work, we present a collection of algorithms and related software modules for the EyesWeb open architecture (freely available from www.eyesweb.org). These software modules, collected in the EyesWeb Expressive Gesture Processing Library, have been used in real scenarios and applications, mainly in the fields of performing arts, therapy and rehabilitation, museum interactive installations, and other immersive augmented reality and cooperative virtual environment applications. The work has been carried out at DIST – InfoMus Lab in the framework of the EU IST Project MEGA (Multisensory Expressive Gesture Applications, www.megaproject.org ).

Proceedings ArticleDOI
07 Oct 2003
TL;DR: This work uses a recent technique of image-based lighting, environment illumination maps, and a simple yet practical multi-pass rendering framework for augmented reality to improve photorealism for rendering synthetic objects in augmented reality.
Abstract: Mixing 3D computer-generated images with real-scene images seamlessly in augmented reality has many desirable and wide areas of applications such as entertainment, cinematography, design visualization and medical trainings. The challenging task is to make virtual objects blend harmoniously into the real scene and appear as if they are like real. Apart from constructing detailed geometric 3D model representation and obtaining accurate surface properties for virtual objects, adopting real scene lighting information to render virtual objects is another important factor to achieve photorealistic rendering. Such a factor not only improves visual complexity of virtual objects, but also determines the consistency of illumination between the virtual objects and the surrounding real objects in the scene. Conventional rendering techniques such as ray tracing, and radiosity require intensive computation and data preparation to solve the lighting transport equation. Hence, they are less practical for rendering virtual objects in augmented reality, which demands a real-time performance. This work explores an image-based and hardware-based approach to improve photorealism for rendering synthetic objects in augmented reality. It uses a recent technique of image-based lighting, environment illumination maps, and a simple yet practical multi-pass rendering framework for augmented reality.

Journal ArticleDOI
TL;DR: AR support proved to be more suitable for difficult tasks than the paper manual, whereas for easier tasks the use of a paper manual did not differ significantly from AR support.
Abstract: Augmented reality (AR) for assembly processes is a new kind of computer support for a traditional industrial domain. This new application of AR technology is called ARsembly. The intention of this article is to describe a typical scenario for assembly and service personnel and how they might be supported by AR. For this purpose, tasks with different degrees of difficulty were selected from an authentic assembly process. In addition, 2 other kinds of assembly support media (a paper manual and a tutorial by an expert) were examined in order to compare them with ARsembly. The results showed that the assembly times varied according to the different support conditions. AR support proved to be more suitable for difficult tasks than the paper manual, whereas for easier tasks the use of a paper manual did not differ significantly from AR support. Tasks done under the guidance of an expert were completed most rapidly. Some of the information obtained in this investigation also indicated important considerations fo...

Proceedings Article
01 Feb 2003
TL;DR: This work construct an indoor tracking system that covers a substantial part of a building and is based on visual tracking of fiducial markers enhanced with an inertial sensor for fast rotational updates.
Abstract: In this work we investigate building indoor location based applications for a mobile augmented reality system We believe that augmented reality is a natural interface to visualize spacial information such as position or direction of locations and objects for location based applications that process and present information based on the user's position in the real world To enable such applications we construct an indoor tracking system that covers a substantial part of a building It is based on visual tracking of fiducial markers enhanced with an inertial sensor for fast rotational updates To scale such a system to a whole building we introduce a space partitioning scheme to reuse fiducial markers throughout the environment Finally we demonstrate two location based applications built upon this facility, an indoor navigation aid and a library search application

Proceedings ArticleDOI
07 Oct 2003
TL;DR: An improved optics design is presented which has reduced size and is lightweight enough to wear and the characteristics of typical multi-user three-dimensional displays are summarized and the design details of the latest optics are described.
Abstract: An ideal augmented reality (AR) display for multi-user co-located collaboration should have following three features: 1) any virtual object should be able to be shown at any arbitrary position, eg a user can see a virtual object in front of other users' faces 2) Correct occlusion of virtual and real objects should be supported 3) The real world should be naturally and clearly visible, which is important for face-to-face conversation We have been developing an optical see-through display, ELMO (Enhanced see-through display using an LCD panel for Mutual Occlusion), that satisfies these three requirements While previous prototype systems were not practical due to their size and weight, we have come up with an improved optics design which has reduced size and is lightweight enough to wear In this paper, the characteristics of typical multi-user three-dimensional displays are summarized and the design details of the latest optics are then described Finally, a collaborative AR application employing the new display and its user experience are explained

Proceedings ArticleDOI
02 Nov 2003
TL;DR: A novel visualization system for video surveillance based on an Augmented Virtual Environment (AVE) that fuses dynamic imagery with 3D models in a real-time display to help observers comprehend multiple streams of temporal data and imagery from arbitrary views of the scene.
Abstract: Recent advances in sensing and computing technologies have inspired a new generation of data analysis and visualization systems for video surveillance applications. We present a novel visualization system for video surveillance based on an Augmented Virtual Environment (AVE) that fuses dynamic imagery with 3D models in a real-time display to help observers comprehend multiple streams of temporal data and imagery from arbitrary views of the scene. This paper focuses on our recent technical extensions to our AVE system, including moving object detection, tracking, and 3D display for effective dynamic event comprehension and situational awareness. Moving objects are detected and tracked in video sequences and visualized as pseudo-3D elements in the AVE scene display in real-time. We show results that illustrate the utility and benefits of these new capabilities.

Proceedings ArticleDOI
07 Oct 2003
TL;DR: In this article, a user study was conducted to determine which representations best express occlusion relationships among far-field objects, and a drawing style and opacity setting was identified to accurately interpret three layers of occluded objects, even in the absence of perspective constraints.
Abstract: A useful function of augmented reality (AR) systems is their ability to visualize occluded infrastructure directly in a user's view of the environment. This is especially important for our application context, which utilizes mobile AR for navigation and other operations in an urban environment. A key problem in the AR field is how to best depict occluded objects in such a way that the viewer can correctly infer the depth relationships between different physical and virtual objects. Showing a single occluded object with no depth context presents an ambiguous picture to the user. But showing all occluded objects in the environments leads to the "Superman's X-ray vision" problem, in which the user sees too much information to make sense of the depth relationships of objects. Our efforts differ qualitatively from previous work in AR occlusion, because our application domain involves far-field occluded objects, which are tens of meters distant from the user. Previous work has focused on near-field occluded objects, which are within or just beyond arm's reach, and which use different perceptual cues. We designed and evaluated a number of sets of display attributes. We then conducted a user study to determine which representations best express occlusion relationships among far-field objects. We identify a drawing style and opacity settings that enable the user to accurately interpret three layers of occluded objects, even in the absence of perspective constraints.

01 Jan 2003
TL;DR: This work discusses how AR may have a unique and powerful link to spatial knowledge acquisition through visuo-motor involvement in the processing of information, and identifies key properties of AR interfaces and how they differ from conventional visualization interfaces.
Abstract: Augmented reality (AR) is an emergent class of interface that presents compelling possibilities for advancing spatial visualization. We offer a brief overview of AR technology and current research with in the educational realm. AR interfaces appear to provide a unique combination of visual display properties, modes of user manipulation, and interaction with spatial information. Drawing upon aspects of proprioception and sensorimotor function, we discuss how AR may have a unique and powerful link to spatial knowledge acquisition through visuo-motor involvement in the processing of information. We identify key properties of AR interfaces and how they differ from conventional visualization interfaces, followed by a discussion of theoretical perspectives that make a case for learning spatial relationships using 1st person manipulative AR. Recent research provides evidence that this form of AR holds cognitive advantages for learning when compared with traditional desktop 2D interfaces. We review the visual-physical connections to learning using 1st person manipulative AR within educational contexts. We then provide some suggestions for building future research in this area and explore its significance in the realm of spatial knowledge acquisition.

Proceedings ArticleDOI
07 Oct 2003
TL;DR: A general method for real-time, vision-only single-camera simultaneous localisation and mapping (SLAM) - an algorithm which is applicable to the localisation of any camera moving through a scene - is presented and its application to theLocalisation of a wearable robot with active vision is studied.
Abstract: We present a general method for real-time, vision-only single-camera simultaneous localisation and mapping (SLAM) - an algorithm which is applicable to the localisation of any camera moving through a scene - and study its application to the localisation of a wearable robot with active vision. Starting from very sparse initial scene knowledge, a map of natural point features spanning a section of a room is generated on-the-fly as the motion of the camera is simultaneously estimated in full 3D. Naturally this permits the annotation of the scene with rigidly-registered graphics, but further it permits automatic control of the robot's active camera: for instance, fixation on a particular object can be maintained during extended periods of arbitrary user motion, then shifted at will to another object which has potentially been out of the field of view. This kind of functionality is the key to the understanding or "management" of a workspace which the robot needs to have in order to assist its wearer usefully in tasks. We believe that the techniques and technology developed are of particular immediate value in scenarios of remote collaboration, where a remote expert is able to annotate, through the robot, the environment the wearer is working in.

Proceedings ArticleDOI
22 May 2003
TL;DR: In this article, the authors discuss the support of manufacturing planning tasks with the Augmented Reality technology and present potential benefits and describe the development of an prototypical AR-System for the support planning tasks.
Abstract: The shortening of development cycles demand for efficient methods and tools for the planning of complex production systems. Recently immersive Virtual Reality technologies have been introduced to the manufacturing planning functions. This has lead to a decrease in planning times as well as to the improvement of the quality of planning results. The introduction of various virtual planning tools is targeting the complete integration of all planning tasks and demands an intuitive interaction with complex computer models of machinery, factory-layouts etc. Known methods and tools are limited to a purely virtual representation of planning objects and thus require the complete modeling of the production system. The high costs reduce the possible benefits of these tools and this technology in general. New potential for the improvement of the industrial planning process are offered by the AR-technology. Using AR-techniques an physically existing production environment can be superimposed with virtual planning objects. Planning tasks can thus be validated without modeling the surrounding environment of the production site. In this contribution we discuss the support of manufacturing planning tasks with the Augmented Reality technology. We present potential benefits and describe the development of an prototypical AR-System for the support of planning tasks.

01 Jan 2003
TL;DR: A virtual flexible pointer is presented that allows a user in a 3D environment to point more easily to fully or partially obscured objects, and to indicate objects to other users more clearly.
Abstract: We present a virtual flexible pointer that allows a user in a 3D environment to point more easily to fully or partially obscured objects, and to indicate objects to other users more clearly. The flexible pointer can also reduce the need for disambiguation and can make it possible for the user to point to more objects than currently possible with existing egocentric techniques.

Proceedings ArticleDOI
01 Oct 2003
TL;DR: A modified real-time shadow volume algorithm that can be used in an Augmented/Mixed Reality application and the proposed concepts provide a novel sense of visual output of an AR application.
Abstract: Shadows add a level of realism to a rendered image. Moreover, they are used as visual clues to determine spacial relationships and real-time shadows will gain importance in current real-time computer graphics applications for this reason. Twenty-five years ago, Crow published the shadow volume approach for determining shadowed regions of a scene. In this paper we present a modified real-time shadow volume algorithm that can be used in an Augmented/Mixed Reality application. Finally, the proposed concepts provide a novel sense of visual output of an AR application.

Proceedings ArticleDOI
07 Oct 2003
TL;DR: The effects of shadow representation of virtual objects in augmented reality is described and it is found that users report that a characteristic shadow shape provides more virtual object presence in spite of incorrect virtual light direction.
Abstract: In this paper, we describe the effects of shadow representation of virtual objects in augmented reality. Optical consistency is important in order to create realistic augmented reality environments. We focus on providing accurate shadows and made two assumptions about the effects of shadow representation of virtual objects. First, that the shadow of virtual objects provides a stronger connection between the real world and virtual objects and so increases virtual object presence. Second, that the shadow of virtual objects provides depth cues and so makes three-dimensional perceptions easier for the users of the interface. We report on two experiments that show that these assumptions are correct. We also find that users report that a characteristic shadow shape provides more virtual object presence in spite of incorrect virtual light direction.