• Publikationen
Show publication details

Wuest, Harald; Engelke, Timo; Schmitt, Florian; Keil, Jens

From CAD to 3D Tracking - Enhancing & Scaling Model-Based Tracking for Industrial Appliances

2016

Mayol-Cuevas, Walterio (Ed.) et al.: 2016 IEEE International Symposium on Mixed and Augmented Reality : ISMAR 2016. Los Alamitos, Calif.: IEEE Computer Society, 2016, 2 p.

IEEE International Symposium on Mixed and Augmented Reality (ISMAR) <15, 2016, Merida, Mexico>

For Augmented Reality to succeed in industrial appliances, industries demand not only robust and reliable tracking techniques, but also a scalable and performant pipeline, that is easy-to-integrate within the existing data- and content environment and that enables vendors to create tracking solutions on their own. In our demo, we present recent advances of our model tracking pipeline and tracking technology, which on the one hand is easy use and easy to integrate, while on the other hand robust enough during difficult environmental conditions and which delivers high accuracy for the industrial domain. We showcase our results inside an AR-manual scenario.

Show publication details

Bernhard, Felix; Kuijper, Arjan (Betreuer); Engelke, Timo (Betreuer)

Benutzerfreundliche Kalibrierung für Tracking von Optical Stereo See-Through Head Worn Displays für Augmented Reality

2015

Darmstadt, TU, Bachelor Thesis, 2015

In recent time devices like Google Glass and Oculus Rift gained a lot of public attention. So the field of Virtual and Augmented Reality has become a more and more attractive field of study. This thesis focuses on the Epson Moverio BT-200, an Optical Stereo See-Through Head Worn Display (OST-HWD or OST-HMD) which can be used for Augmented Reality. Augmented Reality devices like this have to be calibrated. This means, that one has to find a configuration, that aligns the image shown on the displays with the environment, which is observed by the built-in camera. If this is not done, the augmented virtual image would not align with the real world. The process of this calibration approach is divided into two stages, like Owen et al. [24] proposed in earlier work, but with less constrains for the positions of the cameras, which makes it easier to use. The first stage is the hardware calibration. It defines the camera intrinsics, containing focal length and principal point, the camera extrinsics, representing the position of the device in world coordinates, as well as the position of the virtual plane onto which the virtual image is projected. The second stage is the user calibration, which calibrates the eye positions for every individual user. An earlier approach by the Fraunhofer IGD [31][32] has been adopted in this work, aiming at a more user friendly suite for the calibration of OST-HWD devices. Therefor both of the aforementioned stages are combined in a new quick step-by-step installation wizard, which is written in HTML and JavaScript to ensure easy usability. Furthermore the VisionLib, developed by Fraunhofer IGD, is used to for image detection and processing [7]. It has been extended by a new minimization model in order to simplify and robustify the calculations of the virtual plane. In addition to that the required hardware components, including camera and calibration rig, were simplified. The implemented software has been evaluated for its results of the computed virtual plane, intrinsic data and eye positions of the user. Furthermore a user study was conducted to rate the usability of the calibration process.

Show publication details

Engelke, Timo; Keil, Jens; Rojtberg, Pavel; Wientapper, Folker; Schmitt, Michael; Bockholt, Ulrich

Content First - A concept for Industrial Augmented Reality Maintenance Applications using Mobile Devices

2015

ACM SIGMM: MMSys '15 : Proceedings of the 6th ACM Multimedia Systems Conference. New York: ACM, 2015, pp. 105-111

Multimedia Systems Conference (MMSys) <6, 2015, Portland, OR, USA>

Although AR has a long history in the area of maintenance and service-support in industry, there still is a lack of lightweight, yet practical solutions for handheld AR systems in everyday workflows. Attempts to support complex maintenance tasks with AR still miss reliable tracking techniques, simple ways to be integrated into existing maintenance environments, and practical authoring solutions, which minimize costs for specialized content generation. We present a general, customisable application framework, allowing to employ AR and VR techniques in order to support technicians in their daily tasks. In contrast to other systems, we do not aim to replace existing support systems such as traditional manuals. Instead we integrate well-known AR- and novel presentation techniques with existing instruction media. To this end practical authoring solutions are crucial and hence we present an application development system based on web-standards such as HTML,CSS and X3D.

Show publication details

Vayanou, Maria; Katifori, Akrivi; Karvounis, Manos; Kourtis, Vassilis; Kyriakidi, Marialena; Roussou, Maria; Tsangaris, Manolis; Ioannidis, Yannis; Balet, Olivier; Prados, Thibaut; Keil, Jens; Engelke, Timo; Pujol, Laia

Authoring Personalized Interactive Museum Stories

2014

Mitchell, Alex (Ed.) et al.: Interactive Storytelling : 7th International Conference on Interactive Digital Storytelling. ICIDS 2014. Berlin, Heidelberg, New York: Springer, 2014. (Lecture Notes in Computer Science (LNCS) 8832), pp.37-48

Joint International Conference on Interactive Digital Storytelling (ICIDS) <7, 2014, Singapore>

CHESS is a research prototype system aimed at enriching museum visits through personalized interactive storytelling. Aspiring to replace traditional exhibit-centric descriptions by story-centric cohesive narrations with carefully-designed references to the exhibits, CHESS follows a plot-based approach, where the story authors create stories around pre-selected museum themes. In this paper we place the CHESS system within the Interactive Digital Narrative field, describing the main objectives and requirements addressed. We present the system's architecture and outline its overall functionality. We describe the underlying storytelling model using examples from the stories authored using the CHESS Authoring Tool. Finally, we report key results focusing on the authors' perspective for the creation of personalized stories.

Show publication details

Katifori, Akrivi; Karvounis, Manos; Kourtis, Vassilis; Kyriakidi, Marialena; Roussou, Maria; Tsangaris, Manolis; Vayanou, Maria; Ioannidis, Yannis; Balet, Olivier; Prados, Thibaut; Keil, Jens; Engelke, Timo; Pujol, Laia

CHESS: Personalized Storytelling Experiences in Museums

2014

Mitchell, Alex (Ed.) et al.: Interactive Storytelling : 7th International Conference on Interactive Digital Storytelling. ICIDS 2014. Berlin, Heidelberg, New York: Springer, 2014. (Lecture Notes in Computer Science (LNCS) 8832), pp. 232-235

Joint International Conference on Interactive Digital Storytelling (ICIDS) <7, 2014, Singapore>

In this work, we present the CHESS research prototype system which offers personalized, interactive digital storytelling experiences to enhance museum visits, demonstrating the authoring and visiting experiences.

Show publication details

Keil, Jens; Engelke, Timo; Schmitt, Michael; Bockholt, Ulrich; Pujol, Laia

Lean In or Lean Back? Aspects on Interactivity & Mediation in Handheld Augmented Reality in the Museum

2014

Klein, Reinhard (Ed.) et al.: GCH 2014. Short Papers - Posters : Eurographics Workshop on Graphics and Cultural Heritage. Goslar: Eurographics Association, 2014, pp. 17-20

Eurographics Symposium on Graphics and Cultural Heritage (GCH) <12, 2014, Darmstadt, Germany>

With the idea to design augmented reality experiences that attract and inform, and which are also seamlessly incorporated into interactive museum narratives, this paper explores finding the appropriate balance between attraction, interactivity and information mediation from the user's point of view. Within the scope of research project CHESS, we've implemented techniques that fuse interaction and mediation to enrich visits to cultural institutions by visual means and AR specific interactions. While it is AR's wow-effect that attracts, our findings show that users far too often struggle to cope with the system and interactivity instead of focusing on the information presentation in AR. We discuss our results of finding the right balance between interactive (lean-in) and non-interactive (lean-back) presentation and interaction techniques in AR.

Show publication details

Perey, Christine; Manson, Rob; Preda, Marius; Trevett, Neil; Lechner, Martin; Percivall, George; Engelke, Timo; Lefkin, Peter; Mahone, Bruce; Nielsen, Mary Lynne

Open and Interoperable Augmented Reality

2014

Julier, Simon (Ed.) et al.: IEEE International Symposium on Mixed and Augmented Reality - Science & Technology 2014 : ISMAR 2014. Piscataway, NJ: IEEE Service Center, 2014, 3 p.

IEEE International Symposium on Mixed and Augmented Reality (ISMAR) <13, 2014, Munich, Germany>

This tutorial provides comprehensive and in depth information that content publishers and developers need to know when planning to develop and deploy content for AR and designing the AR experiences in a manner that supports maximum reach and data portability. The tutorial presenters are experts in the area of individual standards and open source projects. They will describe open protocols and APIs that can be integrated with existing proprietary technology silos or used as alternatives to reduce delays and cost over the lifetime of AR-assisted system development and ownership.

Show publication details

Wientapper, Folker; Engelke, Timo; Keil, Jens; Wuest, Harald; Mensik, Johanna

User Friedly Calibration and Tracking for Optical Stereo See-Through Augmented Reality

2014

Julier, Simon (Ed.) et al.: IEEE International Symposium on Mixed and Augmented Reality - Science & Technology 2014 : ISMAR 2014. Piscataway, NJ: IEEE Service Center, 2014, pp. 385-386

IEEE International Symposium on Mixed and Augmented Reality (ISMAR) <13, 2014, Munich, Germany>

Optical see through head mounted displays (OST-HMD) are ever since the first days of Augmented Reality (AR) in focus of development and in nowadays first affordable and prototypes are spread out to markets. Despite common technical problems, such as having a proper field of view, weight, and other problems concerning the miniaturization of these systems, a crucial aspect for AR relies also in the calibration of such a device with respect to the individual user for proper alignment of augmentations. Our demonstrator shows a practical solution for this problem along with a fully featured example application for a typical maintenance use case based on a generalized framework for application creation. We depict the technical background and procedure of the calibration, the tracking approach considering the sensors of the device, user experience factors, and its implementation procedure in general. We present our demonstrator using an Epson Moverio BT-200 OST-HMD.

Show publication details

Keil, Jens; Pujol, Laia; Roussou, Maria; Engelke, Timo; Schmitt, Michael; Bockholt, Ulrich; Eleftheratou, Stamatia

A Digital Look at Physical Museum Exhibits: Designing Personalized Stories with Handheld Augmented Reality in Museums

2013

2013 Digital Heritage International Congress. Volume 2 : DigitalHeritage. New York: The Institute of Electrical and Electronics Engineers (IEEE), 2013, pp. 685-688

Digital Heritage International Congress (DigitalHeritage) <2013, Marseille, France>

In this paper we present the design of handheld Augmented Reality (AR) experiences that are seamlessly incorporated into interactive museum narratives, specifically for the Acropolis Museum. The experiences start by forming a visitor profile that later dynamically adapts the narrative, including the AR activities, to the user's behaviour. In this cohesive narrative context, the AR activities provide four ways to digitally look at the exhibits: virtual reconstruction of the original aspect; placement in the original location; visual highlighting of interesting details and annotations; and recreation of mythological appearances. The challenges of this design are presented, concluding with a discussion and lessons learned.

Show publication details

Bockholt, Ulrich; Wuest, Harald; Wientapper, Folker; Engelke, Timo; Webel, Sabine

Augmented Reality Assistenzsysteme für Wartung und Service in Industrie, Bau und Gebäudemanagement

2013

Schenk, Michael (Ed.): 16. IFF-Wissenschaftstage 2013. Tagungsband : Digital Engineering zum Planen, Testen und Betreiben technischer Systeme. Stuttgart: Fraunhofer Verlag, 2013, pp. 195-200

IFF-Wissenschaftstage <16, 2013, Magdeburg, Germany>

Für die Nutzbarkeit von Augmented Reality ist die Voraussetzung entscheidend, dass sich der Einsatz von AR im industriellen Kontext insbesondere dann rentiert, wenn sich Skaleneffekte einstellen. Im Bereich von Montage-, Reparatur- und Fehlerdiagnosearbeiten ist dies der Fall, wenn einerseits ein und dieselbe AR-Applikation in hohem Maße mehrfach benutzt werden kann, und andererseits die Erstellung des Trackingmodells hierfür nur einmal durchgeführt werden muss. Mit der Häufigkeit der Anwendung amortisiert sich dann der Aufwand für das einmalige Einrichten der AR-Applikation. Weiterhin ist es für die Akzeptanz von AR-Applikationen vorteilhaft, wenn beim Endanwender keine besonderen Kenntnisse hinsichtlich des Trackings bzw. der Benutzung der AR-Applikation vorausgesetzt werden müssen. Die AR-Applikation sollte den Endanwender bei der Erreichung seiner persönlichen Arbeitsziele unterstützen, ihm jedoch nicht ein zu hohes Maß an zusätzlichem Vorwissen in der Handhabung abverlangen. Seine Aufmerksamkeit sollte nicht darauf ausgerichtet sein, wie er sich verhalten muss, damit das Tracking funktioniert. Vielmehr muss er durch AR schneller, einfacher und intuitiver an die benötigten Informationen gelangen.

Show publication details

Olbrich, Manuel; Graf, Holger; Kahn, Svenja; Engelke, Timo; Keil, Jens; Rieß, Patrick; Webel, Sabine; Bockholt, Ulrich; Picinbono, Guillaume

Augmented Reality Supporting User-centric Building Information Management

2013

The Visual Computer, Vol.29 (2013), 10, pp. 1093-1105

The rapid development of geo-referenced information changed the way on how we access and interlink data. Smartphones as enabling devices for information access are main driving factor. Thus, the hash key to information is the actual position registered via camera and sensory of the mobile device. A rising technology in this context is Augmented Reality (AR) as its fuses the real world captured with the smartphone camera with geo-referenced data. The technological building blocks analyse the intrinsic sensor data (camera, GPS, inertial) to derive a detailed pose of the smartphone aiming to align geo-referenced information to our real environment. In particular, this is interesting to applications where 3D models are used in planning and organization processes as, e.g., facility management. Here, Building Information Models (BIM) were established in order to hold "as built" information, but also to manage the vast amount of additional information coming with the design, such as building components, properties, maintenance logs, documentation, etc. One challenge is to enable stakeholders involved in the overall building lifecycle to get mobile access to the management system within onsite inspections and to automatise feedback of newly generated information into the BIM. This paper describes a new AR framework that offers on-site access to BIM information and user centric annotation mechanism.

Show publication details

Webel, Sabine; Bockholt, Ulrich; Engelke, Timo; Gavish, Nirit; Olbrich, Manuel; Preusche, Carsten

Augmented Reality Training Platform for Assembly and Maintenance Skills

2013

Robotics and Autonomous Systems, Vol.61 (2013), 4, pp. 398-403. First published as Article in Press on 01 November 2012

The training of technicians in the acquisition of new maintenance and assembly tasks is an important factor in industry. As the complexity of these tasks can be enormous, the training of technicians to acquire the necessary skills to perform them efficiently is a challenging point. In this context it is shown that Augmented Reality is a powerful technology to support training in the particular context of industrial service procedures, since instructions on how to perform the service tasks can be directly linked to the machine parts to be processed. Due to the increasing complexity of maintenance tasks, it is not sufficient to train the technicians' execution of these tasks, but rather to train the underlying skills-sensorimotor and cognitive-that are necessary for an efficient acquisition and performance of new maintenance operations. All these facts lead to the need for efficient training systems for the training of maintenance and assembly skills which accelerate the technicians' learning and acquisition of new maintenance procedures. Furthermore, these systems should improve the adjustment of the training process to new training scenarios and enable the reuse of existing training material that has proven its worth. In this context a novel concept and platform for multimodal Augmented Reality-based training of maintenance and assembly skills has been developed, which includes the training of the involved sub-skills and the evaluation of the designed training system. Since procedural skills are considered as the most important skills for maintenance and assembly operations, we focus on the training of these skills, as well as appropriate methods for improving them.

Show publication details

Engelke, Timo; Keil, Jens; Rojtberg, Pavel; Wientapper, Folker; Webel, Sabine; Bockholt, Ulrich

Content First - A concept for Industrial Augmented Reality Maintenance Applications Using Mobile Devices

2013

IEEE Computer Society Visualization and Graphics Technical Committee (VGTC): 12th IEEE International Symposium on Mixed and Augmented Reality 2013. : ISMAR 2013. Los Alamitos, Calif.: IEEE Computer Society, 2013, pp. 251-252

IEEE International Symposium on Mixed and Augmented Reality (ISMAR) <12, 2013, Adelaide, SA, Australia>

Although AR has a long history in the area of maintenance and service-support in industry, there still is a lack of lightweight, yet practical solutions for handheld AR systems in everyday workflows. Attempts to support complex maintenance tasks with AR still miss reliable tracking techniques, simple ways to be integrated into existing maintenance environments, and practical authoring solutions, which minimize costs for specialized content generation. We present a general, customisable application framework, allowing to employ AR and VR techniques in order to support technicians in their daily tasks. In contrast to other systems, we do not aim to replace existing support systems such as traditional manuals. Instead we integrate well-known AR- and novel presentation techniques with existing instruction media. To this end practical authoring solutions are crucial and hence we present an application development system based on web-standards such as HTML,CSS and X3D.

Show publication details

Keil, Jens; Zöllner, Michael; Engelke, Timo; Wientapper, Folker; Schmitt, Michael

Controlling and Filtering Information Density with Spatial Interaction Techniques via Handheld Augmented Reality

2013

Shumaker, Randall (Ed.): Virtual Augmented and Mixed Reality. Designing and Developing Augmented and Virtual Environments. Proceedings Part I : VAMR 2013. Berlin, Heidelberg, New York: Springer, 2013. (Lecture Notes in Computer Science (LNCS) 8021), pp. 49-57

International Conference Virtual Augmented and Mixed Reality (VAMR) <5, 2013, Las Vegas, NV, USA>

In our paper we are proposing a method for contextual information filtering based on the user's movement and location in order to enable the intuitive usage of an "internet of things" via augmented reality (AR) without information overload. Similar to Ray & Charles Eames' "Power of Ten" and Jef Raskin's "Zooming Interface" we are displaying seamless information layers by simply moving around a Greek statue or a miniature model of an Ariane-5 space rocket. Therefore we are employing concepts of camera- and motion-based interaction techniques and use the metaphors of "investigation" and "exploration" to control the way augmented and visually superimposed elements are presented in order to mediate information in an enhanced and engaging manner with aspects of digital storytelling techniques.

Show publication details

Keil, Jens; Engelke, Timo; Pujol, Laia

Interactive Adaptive Storytelling with AR at Acropolis Museum

2013

Pescarin, Sofia et al.: 2013 Digital Heritage International Congress. Volume 3 : E-Catalogue of the Digital Heritage 2013 Expo. Roma: CNR - ITABC edizioni, 2013, pp. 56-57

Digital Heritage International Congress (DigitalHeritage) <2013, Marseille, France>

In this paper we present the design of handheld Augmented Reality (AR) experiences that are seamlessly incorporated into interactive museum narratives, specifically for the Acropolis Museum. The experiences start by forming a visitor profile that later dynamically adapts the narrative, including the AR activities, to the user's behaviour. In this cohesive narrative context, the AR activities provide four ways to digitally look at the exhibits: virtual reconstruction of the original aspect; placement in the original location; visual highlighting of interesting details and annotations; and recreation of mythological appearances. The challenges of this design are presented, conluding with a discussion and lessons learned.

Show publication details

Engelke, Timo; Becker, Mario; Wuest, Harald; Keil, Jens; Kuijper, Arjan

MobileAR Browser - A Generic Architecture for Rapid AR-multi-level Development

2013

Expert Systems with Applications, Vol.40 (2013), 7, pp. 2704-2714

We present our novel generic approach for interfacing web components on mobile devices in order to rapidly develop Augmented Reality (AR) applications using HTML5, JavaScript, X3D and a vision engine. A general concept is presented exposing a generalized abstraction of components that are to be integrated in order to allow the creation of AR capable interfaces on widely available mobile devices. Requirements are given, yielding a set of abstractions, components, and helpful interfaces that allow rapid prototyping, research at application level, as well as commercial applications. A selection of various applications (also commercial) using the developed framework is given, proving the generality of the architecture of our MobileAR Browser. Using this concept a large number of developers can be reached. The system is designed to work with different standards and allows for domain separation of tracking algorithms, render content, interaction and GUI design. This can potentially help groups of developers and researchers with different competences creating their application in parallel, while the declarative content remains exchangeable.

Show publication details

Bockholt, Ulrich; Webel, Sabine; Engelke, Timo; Olbrich, Manuel; Wuest, Harald

Skill Capturing and Augmented Reality for Training

2013

Bergamasco, Massimo (Ed.) et al.: Skill Training in Multimodal Virtual Environments. Boca Raton: Taylor & Francis, CRC Press, 2013, pp. 81-90

AR-based training applications must clearly differ from AR-based guiding applications, as they must really train the user and not only guide the user through the task. AR is a good technology for training, as instructions or location-dependent information can be directly linked and attached to physical objects. Because objects to be maintained usually contain a large number of similar components, the provision of location-dependent information is vitally important for the training. Furthermore, in AR-based training, sessions can be combined with teleconsultation technologies, and the availability of a trainer on-site is not mandatory.

Show publication details

Engelke, Timo; Keil, Jens

WebApp Development for Enhanced Cultural Heritage Experience through mobile Augmented Reality

2013

2013 Digital Heritage International Congress. Volume 2 : DigitalHeritage. New York: The Institute of Electrical and Electronics Engineers (IEEE), 2013, p. 767

Digital Heritage International Congress (DigitalHeritage) <2013, Marseille, France>

The use of mobile devices in cultural heritage is still a new field of research, while the amount of potential applications grows from day to day. Due to the enormous increase of technological capabilities, mobile devices are suitable for performing Augmented Reality in cultural heritage applications. The mobile application framework "instantAR" for iOS and Android devices enables high-level development of Augmented Reality solutions. It provides an efficient environment for the development of AR applications on mobile devices based on common standards like HTML, Javascript and X3D. While providing convenient interfaces and abstractions it maintains great flexibility in order to also realise advanced interaction paradigms for AR. The full day tutorial will introduce into the concepts of the "instantAR" framework, its provided development environment, discuss the possibilities for deploying standards in AR-Systems, demonstrate its capabilities and present the full range of potentials for a deployment in research and commercial environments targeting diverse stakeholders in the cultural heritage domain.

Show publication details

Kahn, Svenja; Olbrich, Manuel; Engelke, Timo; Keil, Jens; Rieß, Patrick; Webel, Sabine; Graf, Holger; Bockholt, Ulrich; Picinbono, Guillaume

Beyond 3D "as-Built" Information using Mobile AR Enhancing the Building Lifecycle Management

2012

Kuijper, Arjan (Ed.) et al.: 2012 International Conference on Cyberworlds. Proceedings : Cyberworlds 2012. Los Alamitos, Calif.: IEEE Computer Society Conference Publishing Services (CPS), 2012, pp. 29-36

International Conference on Cyberworlds (CW) <11, 2012, Darmstadt, Germany>

The success of smartphone technologies changed the way information is processed as more and more geo-referenced structures are emerging linking information to specific locations within our environment. Thereby, Augmented Reality has become a key technology as it analyses the smartphone sensor data (camera, GPS, inertial) to derive the detailed pose of the smartphone, with the aim to correlate our real environment to the geo-referenced information space. In particular, this is relevant for application fields where 3Dmodels are used in planning and organization processes as e.g. facility management. In facility construction and management Building Information Model (BIM) was established as a standard that not only holds the 3D-building-geometry but encompasses pipe/electrical systems as well as semantic building information, for example properties and conditions of building components. With this motivation our work integrates BIM and Augmented Reality.

Show publication details

Schmitt, Michael; Engelke, Timo (Betreuer); Goesele, Michael (Betreuer)

Estimation of Matching Probabilities for Histogrammed Intensity Patches

2012

Darmstadt, TU, Master Thesis, 2012

This work presents a way to estimate the matching probabilities for histogrammed intensity patches [41] by approximating the robustness and distinctiveness of a feature with beta distributions. We propose a simplified analytical approach to calculate the distinctiveness and show that it produces at least as good results as a specifically trained neural network. The matching probability correlates stronger with the inlier ratio than the dissimilarity score does. We then evaluate a basic tracking by detection pipeline where no longer the closest but the most probable match is chosen. Our tests show, that this improves the average performance of the system in terms of tracking rate.

Show publication details

Webel, Sabine; Bockholt, Ulrich; Engelke, Timo; Peveri, Matteo; Olbrich, Manuel; Preusche, Carsten

Augmented Reality Training for Assembly and Maintenance Skills

2011

BIO Web of Conferences, Vol.1 (2011), 4 p.

The International Conference SKILLS <1, 2011, Montpellier, France>

Augmented Reality (AR) points out to be a good technology for training in the field of maintenance and assembly, as instructions or rather location-dependent information can be directly linked and/or attached to physical objects. Since objects to maintain usually contain a large number of similar components (e.g. screws, plugs, etc.) the provision of location-dependent information is vitally important. Another advantage is that AR-based training takes place with the real physical devices of the training scenario. Thus, the trainee also practices the real use of the tools whereby the corresponding sensorimotor skills are trained.

Show publication details

Klose, Stefan; Gerhardt, Jeremie; Engelke, Timo; Kuijper, Arjan

Automatic Multi-projector Calibration: A Review of Systems for Non-experienced Users

2011

Richard, Paul (Ed.) et al.: GRAPP 2011 : Proceedings of the International Conference on Computer Graphics Theory and Applications. Portugal: SciTePress, 2011, pp. 286-295

International Conference on Computer Graphics Theory and Applications (GRAPP) <6, 2011, Vilamoura, Algarve, Portugal>

Multi-projector systems are widely used in many application areas. Such systems are for instance employed to increase the brightness or the resolution of projected images. Intrinsic to multi-projector systems are problems like geometric misalignment, especially when projecting onto complex arbitrarily formed projection surfaces, and photometric deviations. Therefore, several difficult calibration tasks (geometry, brightness, color) have to be performed. A high-quality and easy-to-use calibration process is the key to good usability for untrained or unexperienced users. Due to the fact that manual calibration is time-consuming and imprecise, automatic approaches were developed in recent years. This paper analyzes the most popular state-of-the-art algorithms and setups with respect to their advantages and disadvantages. We summarize the general working principles of calibration algorithms and provide an outlook into the fields in which the described algorithms are most useful.

Show publication details

Perey, Christine; Engelke, Timo; Reed, Carl

Current Status of Standards for Augmented Reality

2011

Alem, Leila (Ed.) et al.: Recent Trends of Mobile Collaborative Augmented Reality Systems. Berlin, Heidelberg, New York: Springer, 2011, pp. 21-38

This chapter discusses the current state, issues, and direction of the development and use of international standards for use in Augmented Reality (AR) applications and services. More specifically, the paper focuses on AR and mobile devices. Enterprise AR applications are not discussed in this chapter. There are many existing international standards that can be used in AR applications but there may not be defined best practices or profiles of those standards that effectively meet AR development requirements. This chapter provides information on a number of standards that can be used for AR applications but may need further international agreements on best practice use.

Show publication details

Webel, Sabine; Bockholt, Ulrich; Engelke, Timo; Gavish, Nirit; Tecchia, Franco

Design Recommendations for Augmented Reality based Training of Maintenance Skills

2011

Alem, Leila (Ed.) et al.: Recent Trends of Mobile Collaborative Augmented Reality Systems. Berlin, Heidelberg, New York: Springer, 2011, pp. 69-82

International Workshop on Mobile Collaborative Augmented Reality (MCAR) <2010, Seoul, South Korea>

Training for service technicians inmaintenance tasks is a classical application field of Augmented Reality explored by different research groups. Mostly technical aspects (tracking, visualization etc.) have been in focus of this research field. In this chapter we present results of interdisciplinary research based on the fusion of cognitive science, psychology and computer science. We focus on analyzing the improvement of Augmented Reality based training of skills which are relevant for maintenance and assembly tasks. The skills considered in this work comprise sensorimotor skills as well as cognitive skills. Different experiments have been conducted in order to find recommendations for the design of Augmented Reality training systems which overcome problems of existing approaches. The suggestions concern the fields of content visualization and multimodal feedback.

Show publication details

Keil, Jens; Zöllner, Michael; Becker, Mario; Wientapper, Folker; Engelke, Timo; Wuest, Harald

The House of Olbrich - An Augmented Reality Tour through Architectural History

2011

IEEE Computer Society Visualization and Graphics Technical Committee (VGTC): 10th IEEE International Symposium on Mixed and Augmented Reality - Arts, Media, and Humanities : ISMAR-AMH 2011. The Institute of Electrical and Electronics Engineers (IEEE), 2011, pp. 15-18

IEEE International Symposium on Mixed and Augmented Reality (ISMAR) <10, 2011, Basel, Switzerland>

With "House of Olbrich" we present an iPhone Augmented Reality (AR) app that visualizes the compelling history of Darmstadt's unique Jugendstil (Art Nouveau) quarter with video-see through Augmented Reality. We propose methods for enabling high performance computer vision algorithms to deploy sophisticated AR visuals on current generation Smartphones by outsourcing resource intensive tasks to the cloud. This allows us to apply methods on 3D feature recognition for even complex tracking situations outdoors, where lightning conditions change and tracked objects are often occluded. By taking a snapshot of the building, the user learns about the architect, design and history of the building. Historical media, like old photographs and blueprints are superimposed on the building's front, depicting the moved history of the famous House of Olbrich, which was destroyed during World War II and has been only rudimentary restored. Augmented Reality technology allows tourists to jump back in time visually by using their Smartphones: Mixing Realities emphasizes the user's experience and leads his attention to the impressive historical architecture of the Art Nouveau. In addition, we ease interaction means by superimposing snapshots. Tourists may view and read information also in a relaxed position without the need to front-up their mobiles all the time.

Show publication details

Engelke, Timo; Webel, Sabine; Gavish, Nirit

Generating Vision based Lego Augmented Reality Training and Evaluation Systems

2010

Höllerer, Tobias (Ed.) et al.: 9th IEEE International Symposium on Mixed and Augmented Reality 2010 : ISMAR. Science & Technology Proceedings. Los Alamitos, Calif.: IEEE Computer Society, 2010, pp. 223-224

IEEE International Symposium on Mixed and Augmented Reality (ISMAR) <9, 2010, Seoul, South Korea>

The creation of training applications using Augmented Reality (AR) is still a new field of research. In order to get good training results therefore evaluation should be performed. For the creation of such systems the questions arising are related to the general process of generation, visualization, evaluation and its psychological background. An important aspect of vision based AR is also the robust tracking and initialization of objects for correct augmentation. In this work we present a concept of an entire processing chain, which allows for efficient and automatic generation of such training systems that can also be used for evaluation. We do this in the context of a Lego training system. While explaining the whole process of application generation and usage, we also present a novel approach for robust marker free initialization of colored partly occluded plates and their tracking using one off the shelf monocular camera.

Show publication details

Engelke, Timo; Webel, Sabine; Bockholt, Ulrich; Wuest, Harald; Gavish, Nirit; Tecchia, Franco; Preusche, Carsten

Towards Automatic Generation of Multimodal AR-Training Applications and Workflow Descriptions

2010

Avizzano, Carlo Alberto (Ed.) et al.: IEEE RO-MAN 2010 : 19th IEEE International Symposium on Robot and Human Interactive Communication. Proceedings [online]. New York: The Institute of Electrical and Electronics Engineers (IEEE), 2010, pp. 434-439

IEEE International Symposium on Robot and Human Interactive Communication (RO-MAN) <19, 2010, Viareggio, Italy>

Augmented Reality (AR) is a technology which has become very popular in the last years. In this context also the idea of using of AR for training applications has become very important. AR offers a large potential for training only if the training is well focused to the skills that have to be trained and if the training protocol is well designed. On the other hand, the generation of the training content to be transferred via AR is a comprehensive problem that is addressed in this paper. Thus, this paper tries to describe the whole chain of implementations and general aspects involved in the creation of AR training applications, including examples for used multimodal devices. This chain starts with the capturing of expert actions to be hold in "digital representation of skill". The digital representation of skill is transferred to the training protocol that specifies the storyboard of the AR training session. The paper includes two different implementations of AR training systems and describes the general idea of informational abstraction from low level data up to interaction and from design to application.

Show publication details

Becker, Mario; Wuest, Harald; Wientapper, Folker; Engelke, Timo

A Prototyping Architecture for Augmented Reality

2009

Latoschik, Marc Erich (Ed.) et al.: 2nd Workshop on Software Engineering and Architectures for Realtime Interactive Systems (SEARIS@VR2009) : IEEE Virtual Reality 2009 Workshop. Aachen: Shaker, 2009, pp. 51-54

Software Engineering and Architectures for Realtime Interactive Systems (SEARIS) <2, 2009, Lafayette, LA, USA>

In this paper we introduce an architecture for rapid development and assessment of advanced 3D visual track ing algorithms. We claim, that no universal tracking approach exists, that fulfills the requirements of all possible application seenarios at the same time. On the contrary, very specific and working solutions can be developed for given situations and uses. Therefore, software for visual tracking must be designed as a highly flexible system that can be quickly re-configured in order to enable the development of optimized solutions in terms of robustness, accuracy, frame rate and delay. To this purpose we designed an architecture that offers many functionalities, which can be combined together to build a new processing chain. The overall system offers numerous advantages, such as interactive programming, run-time access to data and parameters and easy interfacing with other libraries or applications.

Show publication details

Casado, Sara; Engelke, Timo; Gavish, Nirit; Gutiérrez, Teresa; Rodríguez, Jorge; Sánchez, Emilio José; Tecchia, Franco; Webel, Sabine

A Training System for Skills Transfer Involved in Industrial Maintenance and Assembly Tasks

2009

Gutiérrez, Teresa (Ed.) et al.: SKILLS 09 : Enaction on SKILLS. Donostia - San Sebastián: SKILLS Consortium, 2009, pp. 129-134

International Conference on Multimodal Interfaces for Skills Transfer (SKILLS) <1, 2009, Bilbao, Spain>

The present paper describes a multimodal training system to be used in the context of Industrial Maintenance and assembly. The system is being developed by the SKILLS consortium members as a dedicated platform to conduct controlled skill transfer exercises as well as the technological platform to develop a dedicated training program. The paper provides an introduction to the current state of the demonstrator, which is now at the first stage of an iterative process that will see the final demonstrator delivered in 2011.

Show publication details

Gavish, Nirit; Engelke, Timo; Webel, Sabine; Bockholt, Ulrich

Enhancing Trainee's Mental Model During AR Assembly Training

2009

Gutiérrez, Teresa (Ed.) et al.: SKILLS 09 : Enaction on SKILLS. Donostia - San Sebastián: SKILLS Consortium, 2009, pp. 189-190

International Conference on Multimodal Interfaces for Skills Transfer (SKILLS) <1, 2009, Bilbao, Spain>

When a learner of a new procedural skill is provided with elaborated knowledge: "how-it-works" knowledge or "context procedures", in addition to the "how-to-do-it" knowledge or "list procedures", his performance becomes more accurate, faster, and more flexible. It is hypnotized that a display of the device which is assembled during the assembly task has the potential to support the trainee's mental model building.

Show publication details

Malerczyk, Cornelius; Engelke, Timo

Intuitive Interaction with VR Applications Using Video-based Gesture Recognition

2009

Latoschik, Marc Erich (Ed.) et al.: 2nd Workshop on Software Engineering and Architectures for Realtime Interactive Systems (SEARIS@VR2009) : IEEE Virtual Reality 2009 Workshop. Aachen: Shaker, 2009, pp. 37-40

Software Engineering and Architectures for Realtime Interactive Systems (SEARIS) <2, 2009, Lafayette, LA, USA>

This paper describes the implementation od a deviceless interaction 'device' using hand gesture recognition within a calibrated stereo system. Video-based interaction is one of the most intuitive kinds of Human Computer Interaction with Virtual Reality applications due to the fact that users are not wired to a computer. If interaction with three-dimensional environments is considered, pointing, grabbing and releasing are the most intuitive gestures used by humans. This paper describes a video-based gesture recognition that observes the user in front of a large displaying screen, indentifying three different hand gestures in real time using 2D feature classification and determines 3D information like the 3D position of the user's hand or the pointing direction if performed. Different scenario applications like a virtual chess game against the computer or an industrial scenario have been deployed and tested.

Show publication details

Jung, Yvonne; Keil, Jens; Wuest, Harald; Engelke, Timo; Rieß, Patrick; Behr, Johannes

Knowledge at Your Fingertips: Multi-touch Interaction for GIS and Architectural Design Review Applications

2009

Institute for Systems and Technologies of Information, Control and Communication (INSTICC): VISIGRAPP 2009. Proceedings : International Joint Conference on Computer Vision and Computer Graphics Theory and Applications [CD-ROM]. INSTICC Press, 2009, GRAPP, pp. 387-392

International Conference on Computer Graphics Theory and Applications (GRAPP) <4, 2009, Lisboa, Portugal>

This paper introduces novel techniques of interacting and controlling 3D content using multi-touch interaction principles for navigation and virtual camera control. Based on applications from GIS and for the architectural design review process, implementation and usage of these interaction techniques are illustrated. A comprehensive hardware and software setup is used, which not only includes tracking, but also an X3D based layer to simplify application development. Therefore it allows designers and other non-programmers to develop multi-touch applications very efficiently, while allowing to focus on user interaction and content.

Show publication details

Bockholt, Ulrich; Webel, Sabine; Engelke, Timo; Graf, Holger; Behr, Johannes

Virtual and Augmented Reality Training Platforms for Transfer of Skills

2009

Gutiérrez, Teresa (Ed.) et al.: SKILLS 09 : Enaction on SKILLS. Donostia - San Sebastián: SKILLS Consortium, 2009, pp. 39-45

International Conference on Multimodal Interfaces for Skills Transfer (SKILLS) <1, 2009, Bilbao, Spain>

Within the European project SKILLS Virtual and Augmented Reality platforms have been developed that are used for the realization of different training simulators in the field of sports (training of rowing and juggling), surgery (training of maxillofacial and telerobotic surgery), rehabilitation (rehabilitation of upper limp), maintenance (training of assembly procedures) and robotics (training of robot programming). These platforms are integrating capturing and rendering technologies. The capturing technologies are used to register specific criteria of skills to be hold in a digital representation. Thus, parameters relevant for specific skills are qualified and used as evaluation factors within the training simulators. The training simulators not only can simulate the virtual environment of the training situation, but this environment can be enhanced via multimodal renderings, fostering the training process and accelerating the training effect. The integrative platforms from scalable and adaptable frameworks that can be used to realize different training protocols and that can be adapted to the trainee's degree of skill. Therefore the training protocol can be specified via standardized application scripts.

Show publication details

Jung, Yvonne; Keil, Jens; Behr, Johannes; Webel, Sabine; Zöllner, Michael; Engelke, Timo; Wuest, Harald; Becker, Mario

Adapting X3D for Multi-touch Environments

2008

Spencer, Stephen N. (Ed.): Proceedings WEB3D 2008 : 13th International Symposium on 3D Web Technology. New York: ACM Press, 2008, pp. 27-30

International Conference on 3D Web Technology (WEB3D) <13, 2008, Los Angeles, CA, USA>

Multi-touch interaction on tabletop displays is a very active field of todays HCI research. However, most publications still focus on tracking techniques or develop a gesture configuration for a specific application setup. Very few explore generic high level interfaces for multi-touch applications. In this paper we present a comprehensive hardware and software setup, which includes an X3D based layer to simplify the application development process. We present a robust FTIR based optical tracking system, examine in how far current sensor and navigation abstractions in the X3D standard are useful and finally present extensions to the standard, which enable designers and other non-programmers to develop multi-touch applications very efficiently.