Simulating the visual appearance and lighting of human skin is a difficult task, which is addressed by researchers for several years now. With the availability of high performance, programmable graphics boards, now it is possible to use techniques formerly only available to offline rendering. In this paper we present solutions to improve the visual quality of human skin by enhancing such techniques to real-time application. Furthermore dynamic properties like aging and emotional changes in the appearance of a face like blushing and weeping are introduced to obtain convincing results at interactive frame rates for really immersive virtual worlds.
In this paper we will explain our approach to create and animate vir-tual characters for real-time rendering applications in an easy and intuitive way. Furthermore we show a way how to develop interactive storylines for such real-time environments involving the created characters. We outline useful exten-sions for character animation based on the VRML97 and X3D standards and de-scribe how to incorporate commercial tools for an optimized workflow. These results were developed within the Virtual Human project. A short overview of the project is included in this paper.
We present a method for realistic, real-time simulation of human hair, which is suitable for the use in complex virtual reality applications. The core idea is to reduce the enormous amount of hair on a human head by combining neighbored hair into wisps and use our cantilever beam algorithm to simulate them. The final rendering of these wisps is done using special hardware accelerated shaders, which deliver high visual accuracy. Furthermore we present our first attempt for interactive hair styling.
Download: Poster INTETAIN05
As of today one of the major application domains for Augmented Reality is the service and maintenance of manufactured products, e.g. cars, planes, large machinery. In this area, Augmented Reality is used to support the service personnel in carrying out their repair tasks by augmenting context-sensitive, additional, virtual information in their field of view. One major problem is the creation of such information. In this paper the authors describe a concept and its realization, which heavily simplifies the creation of AR based manuals and even allows people without special AR and IT skills to carry out this task. The core idea is template based authoring: The editor of an AR based manual describes scenes at a very high and abstract level for example ”remove the v-belt” or “dismantle acoustic cover of the engine”. The tool transforms this description into VRML-based statements including animations (e.g. transformation of geometrical objects, use of PositionInterpolators). Furthermore the authors describe the realization of the tool and its integration in an AR environment.
Download: Präsentation IEEE VR2005 (pdf) (My presentation on IEEE VR 2005)
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All modern VR and AR toolkits provide some kind of sensor abstraction for different types of input and output devices and user interaction. Almost all systems today define a single layer of abstraction. Most toolkits usually support only low level data streams leaving most of the user interface implementation work to the IT professional. Some provide only high level interaction responder (e.g. X3D) without the possibility to access low level I/O information and streams. No toolkit supports adoption of UI elements to the environment the user is working in, e.g. immersive or desktop.
In our approach we build three level of abstraction for user interaction which leads to a more flexible and scalable result. Application programmers are free to use low level streams (e.g. tracker data) directly, high level responder (e.g. the user `touched' something) and even application requests (e.g. the systems needs a oat input or a list of selected objects) which are automatically mapped to 2D UI elements or immersive responder, depending on the environment and used devices. Two examples illustrate the flexibility and efficiency of our approach.
Virtual reality is a technology that has developed very rapidly in the
past years, and it can now be found in numerous areas of application. Special
input and output devices, real-time graphics and immersive applications
characterize the current image of virtual reality (VR). But virtual reality
is one thing above all else: an innovative human/machine interface with
the goal of making interaction with the virtual world as natural, intuitive
and interactive as possible.
Despite, or perhaps because of this objective, the same issues arise each
time a new VR-based application is developed. The first issue involves
determining and implementing the functionalities that the new application
must cover. Here, research can assist primarily in fulfilling the requirements
of the real-time application. The second issue is the design and implementation
of the interaction interface, which is essential to the overall usability
of the system and therefore also has a major influence on user acceptance.
In this area, however, there is a lack of well defined concepts and procedures
which would greatly facilitate user interface development. Although approaches
and solutions have been developed again and again over the past years which
partially meet the requirements of VR-based user interfaces, the inability
to organize them in a predefined scheme or global context have severely
restricted their reusability.
The goal of this thesis was to develop a comprehensive approach which
makes it possible to identify and classify variables, parameters and boundary
conditions which are critical to the design of a user interface. Based
on this classification, guidelines for the development of a VR user interface
could then be derived and interaction techniques suitable to the application
could be determined. Appropriate basic software concepts are needed in
order to ensure the reusability of the developed components and the ability
on the side of the application to react flexibly to changes in the
boundary conditions affecting the user interface. To fulfil the requirements
of the comprehensive approach, these aspects were also included in the
target definition and were handled using the BIT architecture developed
in the thesis, among other things.
VR design review, which is used very widely in industry, was chosen as
an example of application. This guaranteed that the approaches which were
developed could be used on a broad basis. VR design review also addresses
issues regarding functionality and content while taking into account boundary
conditions that have not yet been fully explored in research. These were
also examined in the paper, and corresponding solutions were developed.
Download: Titelseite (pdf), Inhaltsverzeichnis (pdf), Kapitel (pdf) (auf Deutsch)
This paper describes the usage of Computer Graphics and Interactive, Digital Storytelling Concepts within the Virtual Human project and its technical platform. Based on a brief overview of the Virtual Human approach, global aims and first R&D results, the Virtual Human platform is introduced. Hereby, methods and concepts for the authoring environment, the narration engine and the avalon player as rendering platform are provided as well as an overview of the Direction and Player Markup Language used for interfaces purposes between these components. Finally, our current Virtual Human demonstrator recently presented at CeBIT 2004 in Hannover using these methods and concepts is described and further R&D activities are pointed out within a brief summary and outlook.
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In this paper we will describe a method for color and brightness correction of multi-projector display systems. This method allows to adjust the rendering output of two or more projectors with different color gamuts in such a way that the projected images look the same, and are photometrically calibrated. Since the correction has to be done for each pixel, a straightforward implementation would be very slow and far away from realtime. Consequently we will outline a method how to improve performance and overcome this limitation. The method is especially useful for IPTs based on digital projectors or stereo separation based on spectral color bands (Infitec(tm)). The method itself is used in two new projection systems, which are currently under construction at Fraunhofer-IGD: The HEyewall and the Digital CAVE. The HEyeWall is the first stereo capable tiled display worldwide. The Digital CAVE is the first CAVE with digital projectors and stereo separation based on Infitec(tm). In this paper we will present these new IPTs in more detail and also present our experience with digital projectors.
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This paper presents and discusses the results of the project ARVIKA. After a short introduction and presentation of the project goals, the Augmented Reality system is described. It consists in a Plug-In for Internet-browser in which all the software components have been integrated. The advantages and disadvantages of the adopted approaches, as well as the lessons learned from the project are presented in details. Finally, the open issues are discussed and future work to be achieved until a possible implementation of Augmented Reality in an industrial context is proposed.
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In this paper we will present a classification scheme for applications, the 4W-model, which helps to derive requirements for the design of a VR user interface for a given application type. Furthermore we will present several basic rules for the design of a VR based interaction technique. Finally we outline how the 4W-model is used on the application area "Design Review" and how the software systems are designed.
Are Virtual and Augmented Reality (VR/AR) well suited for entertaining and educating a lay audience? In this paper we try to find an answer to this question and work out the conditions and requirements for successful installations. We will describe our "testbed", the Cybernarium Days 2002, the world's first public exhibition exclusively dedicated to Virtual and Augmented Reality, which attracted more than 10.000 visitors in 6 days. We also present the results of the user questioning, which took place during the exhibition, and the "lessons learnt". Furthermore we focus on software aspects, which enabled us to use low cost hardware and offered a way to build new exhibits in a short time. Since the raise or fall of a VR/AR installation is mainly influenced by its user interface, we present a classification scheme for devices and outline their advantages and disadvantages, offering other VR/AR-developers a guideline for their work on public VR/AR-exhibits.
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In this paper we will present an approach how to support collaborative work between several experts in a design review based on CAD data. The design review is an important part of the design process of a new product, because its objective is to ensure the quality of the final product. During a design review several experts discuss the current state of the work, trying to locate errors in the design, develop improvements or find solutions for unsolved problems. It is evident that the quality of the achieved results of such a review is directly linked to the quality of the collaboration between the involved experts. Apart from social issues, efficient collaboration is heavily influenced by technical aspects, e.g. which kind of media is used. Since pure digital data representations of the design is commonplace today, new metaphors have to be developed which allow a group of people to work together simultaneously and intuitively on the same data model.
Abstract: In this paper, innovative technologies for the presentation of complex cultural heritage sites with immersive 3D computer graphics are introduced, which are based on new concepts, partly having been adopted from other computer graphics areas to the specific needs for cultural heritage presentations, partly having been developed especially for this purpose. The main focus of this project was to develop new concepts for the integration of historical, architectural, and cultural data related to a cultural heritage site, into an immersive Virtual Reality (VR) Environment suited for presentation of the digital model. These concepts include digital storytelling, virtual 3D avatars and 3D agents. The 3D avatar was implemented as a virtual tourist guide, who accompanies the visitors on their tour and shows them the places of interest.
Furthermore, specifics of the very detailed and complex digital models of cultural heritage sites are addressed, in order to meet the high quality requirements of an interactive 3D visualisation. Special focus has been put on both the frame rate and the visual quality. Beside Level-of-detail mechanisms, texture-paging techniques have been developed to allow the use of very high resolution textures. Lighting simulation based on radiosity simulation, which ensure a high visual quality, have been extended for the efficient simulation of global illumination effects within very complex models. These new concepts and techniques have been successfully applied in the immersive VR presentation of a digital model of the cathedral of Siena, which has been shown to the public during the EXPO 2000 in Hannover.
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The Virtual Table presents stereoscopic graphics to usually a single user in a workbench like setting. This paper describes the {\em pen and paper paradigm}, which besides being an easy to use user interface for sketching or similar tasks, provides the possibility for several users to work on the Virtual Table at the same time. They are not only able to move objects or to sketch on them independently, but they even can view the objects they are working on in a stereoscopic mode with the correct perspective due to individual head tracking. This way the Virtual Table becomes usable for groups of users, too. At the same time the pen and paper paradigm in combination with two handed input creates a very intuitive user interface for drawing, sketching or painting tasks.
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In this paper we present the idea of a user oriented simulation method. The principle of using a user oriented simulation method makes the integration of a scientific simulation procedure in Virtual Environments (VEs) possible. Furthermore, we describe our approach to an easy and intuitive use interface for VEs, which addresses the needs of the cable installation application as well as the user's needs. The UI concepts presented here can also be transferred to similar scientific visualisation problems in other domains.
The major goal of today's automotive industry is to shorten the time to market of new products, while spending less money on the whole development. One way to reach this goal is by replacing " physical mock-ups" (PMU) by digital mock up's (DMU), which are faster and cheaper to produce. Nevertheless PMU's have a big advantage when people have to interact with them. Obviously this can be done in a very natural way. Therefore ways have to be found to support the same level of intuitive interaction when using DMU's. VR is the key technology to fulfill this goal. In that paper we will focus on the design review process, which is an important aspect in the whole development cycle. There, experts discuss and evaluate the design and the functionality of the proposed solutions. The assessment is based on CAD data, as well as FE simulation data (e.g. crash). We will present an approach of integrating simulation data within a real-time environment and ways of interacting with these data. Furthermore we will discuss how a design review based on VR technology may look like. The proposed solutions are not bound to the automotive industry, they are also applicable to other domains.
In today's automotive industry there is an increasing demand for VR technology, because it provides the possibility to switch from cost and time insensitive physical mock up's (PMU) to digital mock up's (DMU). Unfortunately many current VR applications are either limited in the way people can interact with them, or provide a large set of functions, which are hard to use. In this paper we present the design of a VR user interface for applications in the area of digital design review. The basic requirements of such an UI are the ease of use, and the ability to work simultaneously with a group of people on one system. Furthermore we investigate the functional requirements for this kind of application, including navigation, manipulation, examination and documentation of flaws in the design of the models. Documentation is stored as HTML and could therefore be easily transmitted between different parties. The design of the user interface is based on the basic interaction tasks (BIT's), introduced by Foley et. al., which allow to build complex functionality on top of only a few interaction metaphors. Finally we evaluate the concept on a prototype implementation, done in cooperation with BMW AG.
In today's automotive industry there is an increasing demand for VR technology, because it provides the possibility to switch from cost and time intensiv physical mock up's (PMU) to digital mock up's (DMU). Furthermore the visualization and examination of simulation results is a very important aspect during the whole development cycle. Therefore tools are needed, which enable the users to work with DMU's, as well as simulation data sets in an efficient and intuitive way. In this paper we present the design of a VR user interface for evaluating simulation data sets. The design of the user interface is based on the basic interaction tasks (BIT's), introduced by Foley et. al.. This allows to generalize the results presented herein and to apply them to other domains.
Sophisticated visualisation enables experts as well as lay persons to extract knowledge from complex data. This is particularly true for visualising the massive amounts of data involved in meteorological observations and simulations. These are of interest to scientists, to forecasters, and to the general public. The paper presents and discusses a range of solutions for meteorlogical visualisation.Topics covered include systems for the production of TV weather forecasts, for the analysis of simulation output by experts, for personalised weather information in the Web, and for meteorological visualisation using Virtual Studio and Augmented Reality technology.
Im November 1996 wurde eine 3-Seiten CAVE [2] am Fraunhofer-IGD installiert. Diese Anlage bestand aus zwei Seitenwänden und einer Bodenprojektion mit einer Projektionsfläche von jeweils 2,4 m x 2,4 m. Mit Hilfe dieser Installation sollte die Technologie eines der faszinierendsten VR Ausgabegeräte aus den Forschungslabors in industrielle Anwendungen übertragen werden. Außerdem sollte die Anwendbarkeit in Bereichen überprüft werden für die traditionelle Ausgabegeräte nur bedingt geeignet sind. Neben der Arbeit an den bereits etablierten Anwendungen sollte auch die Integration in neue innovative Applikationen vorangetrieben werden. Auf den Erfahrungen mit der 3-Seiten CAVE aufbauend, wurde eine 5-Seiten CAVE entwickelt und im Oktober 1997 im neuen Institutsgebäude installiert. Diese CAVE besteht aus 3 Seitenwänden, einer Boden- und einer Deckenprojektion mit einer Projektionsfläche von jeweils 2,4 m ´ 2,4 m. Besonderer Wert wurde bei der Konstruktion auf die nahtlosen Übergänge zwischen den verschiedenen Projektionsflächen gelegt. In diesem Artikel werden werden einige CAVE-Anwendungen präsentiert: Design Review (Architektur, Konstruktion und Planung), Digitale Prototypen (Ein- und Ausbausimulation im Automobilbaubereich und der Schiffskonstruktion), sowie aus dem Bereich Edutainment (Virtuelles Ozeanarium für die EXPO'98). Außerdem werden die Vor- und Nachteile der CAVE-Technologie, auch im Vergleich zu anderen Ausgabegeräten, diskutiert.