Thesis (M.S. in Modeling, Virtual Environments and Simulation)--Naval Postgraduate School, Sept. 2004. / Thesis advisor(s): Michael J. Zyda. Includes bibliographical references (p. 59). Also available online.

Thesis (M.S. in Modeling, Virtual Environments, and Simulation)--Naval Postgraduate School, December 2003. / Thesis advisor(s): Wolfgang Baer, David W. Laflam. Includes bibliographical references (p. 61-63). Also available online.

Thesis (M. E.)--University of New South Wales, 2005. / Also available online.

Tirer un trait pourrait être considéré comme un acte du quotidien, un acte banal, machinal, fonctionnel. Mais cet acte n'est pas anodin: il engage son auteur et l'écriture est un apprentissage parfois difficile.Nous avons abordé le tracé, comme une expérience de la trace (Derrida), expérience singulière vécue du point de vue des sujets en situation de formation. Pour cela, nous avons choisi une activité de calligraphie proposée en formation continue à des professeurs des écoles Cette activité vise indirectement l'apprentissage de l'écriture pour des enfants de 3 à 7ans.Lors d'une activité de calligraphie, le trait de pinceau n'admet pas de repentir. Le "geste décisif" (Cheng) revêt un relief particulier en relation avec la prise de risque qui l'accompagne.Berthoz propose d'aborder la prise de décision comme un différentiel, non seulement entre deux vues (Derrida), mais entre deux corps : entre le corps de “chair sensible” et le corps “interne”, “virtuel” "émulé" par notre cerveau. Entre « invu »(Derrida) et présence virtuelle, la trace n'est pas qu'un objet visible exposé à soi-même comme à autrui, et la comprendre suppose d'embrasser l'ensemble du processus de production du tracé. Ce dernier a été compris en tant qu'acte réalisé du point de vue d'un sujet percevant, au sens de Merleau-Ponty.L'entretien d'aide à l'explicitation mis au point par P. Vermersch a été utilisé pour recueillir de l'information du point de vue du sujet et tenter d'accéder au « vécu de l'expérience ». Ainsi, nous avons réalisé dix-sept entretiens auprès de deux groupes d'enseignants. Le processus d'explicitation vise plus particulièrement à appréhender l'expression du point de vue du sujet en première personne. C'est pourquoi dans un deuxième temps, nous sommes allés aux marges du processus d'explicitation pour nous intéresser à l'expression en troisième personne. En différenciant point de vue en première personne et expression en première personne, nous avons envisagé un point du vue "polyphonique" du sujet parlant (Ducrot) et nous avons constaté que la présence d'une expression en troisième personne, dans ce qui est dit, rend compte de ce qui apparaît comme imperceptible au sujet parlant.L'expression en troisième personne, notamment par la présence de pronoms "démonstratifs" dans ce qui est dit, marque un passage entre un re-vécu de l'acte graphique qui peut se décrire, et un re-vécu d'événements antérieurs qui peut se reconstituer, comme une archéologie de l'histoire singulière du sujet.L'expression émotionnelle, énoncée comme un "re-senti", accompagne ce passage entre explicité et implicite. Elle exprime dans ce qui est dit une possible articulation entre ces deux dimensions (ou deux espaces) de l'expérience. Tout d'abord, la description de l'action re-vécue rend compte de micro-décisions, en amont du tracé calligraphique, qui participent d'un savoir-faire subtil, par lequel les sujets mettent en con-form-ité différents champs de perception. Le tracé est dit réussi par les sujets lorsqu'il est con-forme au tracé pré-vu (voir « ça…là ») et surtout à la perception d'événements antérieurs re-vécus (« c'est ça ») encore insaisissables pour eux-mêmes. Le tracé est une offre de visibilité, qui donne sens à l'acte graphique et à l'activité de formation. Ensuite, en situation de formation collective, les sujets com-posent avec les autres dans l'action et sur le support papier. La composition collective est alors regardée comme un "vécu commun", une expérience vécue avec les autres, expérience qui implique une reconnaissance de l'autre pour lui-même et par laquelle s'élabore un espace d'expérience de soi-même partageable avec autrui.Mots clés : expérience, perception, simulation de l'action, trace, re-vécu. / Abstract :Drawing a line could be considered as a commonplace, mechanical, functional act. But this act is not trivial: it commits its author and writing is sometimes a difficult learning.We dealt with the drawing of a line as an experience of the trace (Derrida), as a singular experience lived from the viewpoint of the subjects in situation of training. For that purpose, we chose an activity of calligraphy in a continuing education course for primary school teachers. This activity aims indirectly at the learning of the writing for children from 3 to 7.During an activity of calligraphy, the brush stroke cannot allow any regret. The "decisive action" (Cheng) is of particular importance in relation to the risk-taking that goes with it.Berthoz suggests approaching the decision-making as a differential, not only between two views (Derrida), but between two bodies: between the body of "sensitive skin" and the "internal", " virtual" body, "emulated" by our brain. Between "unseen” (Derrida) and virtual presence, the trace is not only a visible object exposed to oneself as to others, and understand it involves embracing the whole production process of the line. This was understood as an act done from the viewpoint of a percipient within the meaning of Merleau-Ponty.The interview to the explicitation developed by Vermersch was used to collect information from the viewpoint of the subject and try to access the lived experience. Thus, seventeen interviews were conducted with two groups of teachers. The process of clarification aims more specifically at understanding the expression from the viewpoint of the subject in first person. That is why secondly, we went to the margins of the process of clarification to study the expression in the third person. By differentiating the point of view in first person and expression in the third person, we considered a "polyphonic" viewpoint of the subject speaking (Ducrot) and we noticed that the presence of an expression in the third person, in what is said, reflects what appears to be unnoticeable to the speaking subject.The expression in the third person, especially because of the presence of "demonstrative" pronouns in what is said marks a transition between a “re-lived” experience of the graphic act that can be described, and a “re-lived” experience of past events that can be reconstituted, as an archaeology of the unique story of the subject.The emotional expression, expressed as a "re-felt" experience, accompanies this passage between explicit and implicit. It expresses in what is said a possible link between these two dimensions (or two spaces) of the experience. First, the description of the re-lived action reports micro-decisions, upstream of the calligraphic line, which imply a subtle knowledge, by which the subjects put in con-form-ity different fields of perception. The line is said to be managed/achieved by the subjects when conform to the plan planned ("it there") and especially in the perception of previous re-lived events ("that's it") still elusive for themselves. The line is an offer of visibility, which gives meaning to the graphic act and to the training activity. Then, in a situation of collective training, the subjects com-pose with the others in action and on paper. The collective composition is then considered as a "common real-life experience ", an experience lived with the others, an experience which involves a recognition of the other one for himself and which prepares a space of experience of oneself shareable with others.Keywords:experience, perception, simulation of the action, trace, re-lived experience.

In der Ingenieursausbildung ist die Arbeit an Anlagen und Maschinen ein wesentlicher Baustein, um die Anwendbarkeit, Möglichkeiten und Grenzen der in der Theorie vermittelten Methoden an praktischen Problemstellungen zu erproben und einschätzen zu lernen. Zu diesem Zweck werden an vielen Hochschulen und Universitäten unterschiedliche Versuchsanlagen eingesetzt. Die Errichtung und der Betrieb solcher Anlagen erfordern jedoch Platz und sind typischerweise mit hohem Einsatz personeller und finanzieller Ressourcen verbunden. Dieser Beitrag betrachtet den Einsatz virtueller Versuchsanlagen als eine mögliche Ergänzung der bestehenden Laborinfrastruktur. Virtuelle Anlage sind solche, die nicht physisch existieren, sondern deren dynamisches Verhalten simuliert und in einer 3D-Visualisierungen auf einem Monitor oder in einer VR-Brille dargestellt werden kann. Virtuelle Anlagen haben gegenüber realen Versuchsanlagen viele Vorteile in Bezug auf die Dauer und Kosten für deren Realisierung, sowie deren Erweiterung und Anpassung an neue Lehrinhalte und die Skalierung und Vervielfältigung für den Einsatz in Praktika. Auf der anderen Seite müssen Laboringenieure für die Entwicklung, Pflege und Instandhaltung virtueller Anlagen über andere Kompetenzen (insb. im Bereich der IT und Programmierung) verfügen, als bei realen Anlagen. Zudem wird für den Betrieb solcher Anlagen zusätzliche Soft- und Hardware benötigt. Am Beispiel eines virtuellen Aufzugs beschreibt dieser Beitrag im Einzelnen diese Vor- und Nachteile und gibt Hinweise für den Einsatz einer virtuellen Anlage in Praktika und Übungen.

Due to economic and operational constraints, there is an increasing demand from aviation operators and training manufacturers to extract maximum training usage from the lower fidelity suite of flight simulators. It is possible to augment low-fidelity flight simulators to achieve equivalent performance compared to high-fidelity setups but at reduced cost and greater mobility. In particular for visual manoeuvres, the virtual reality technique of head-tracking amplification for virtual view control enables full field-of-regard access even with limited field-of-view displays. This research quantified the effects of this technique on piloting performance, workload and simulator sickness by applying it to a fixed-base, low-fidelity, low-cost flight simulator. In two separate simulator trials, participants had to land a simulated aircraft from a visual traffic circuit pattern whilst scanning for airborne traffic. Initially, a single augmented display was compared to the common triple display setup in front of the pilot. Starting from the base leg, pilots exhibited tighter turns closer to the desired ground track and were more actively conducting visual scans using the augmented display. This was followed up by a second experiment to quantify the scalability of augmentation towards larger displays and field of views. Task complexity was increased by starting the traffic pattern from the downwind leg. Triple displays in front of the pilot yielded the best compromise delivering flight performance and traffic detection scores just below the triple projectors but without an increase in track deviations and the pilots were also less prone to simulator sickness symptoms. This research demonstrated that head augmentation yields clear benefits of quick user adaptation, low-cost, ease of systems integration, together with the capability to negate the impact of display sizes yet without incurring significant penalties in workload and incurring simulator sickness. The impact of this research is that it facilitates future flight training solutions using this augmentation technique to meet budgetary and mobility requirements. This enables deployment of simulators in large numbers to deliver expanded mission rehearsal previously unattainable within this class of low-fidelity simulators, and with no restrictions for transfer to other training media.

Today highly complex components are manufactured on NC-controlled machine tools. The NC programs, controlling these machines, are usually automatically generated by CAM software. This automatic processing is often erroneous. The VR-based realistic machine simulation, presented in this paper, extends the usual content of a machine simulation, like material removal and collision detection, by various new aspects. The coupling of a real NC unit allows the recognition and elimination of all process- as well as controller-caused errors. The integration of the multi-body simulation enables the consideration of inertia, machine rigidity and milling cutter deflection.

In this thesis, a simulation package for the Six Degrees of Freedom (6DOF) motion of an underwater vehicle is developed. Mathematical modeling of an underwater vehicle is done and the parameters needed to write such a simulation package are obtained from an existing underwater vehicle available in the literature. Basic equations of motion are developed to simulate the motion of the underwater vehicle and the parameters needed for the hydrodynamic modeling of the vehicle is obtained from the available literature. 6DOF simulation package prepared for the underwater vehicle was developed using the MATLAB environment. S-function hierarchy is developed using the same platform with C++ programming language. With the usage of S-functions the problems related to the speed of the platform have been eliminated. The use of Sfunction hierarchy brought out the opportunity of running the simulation package on other independent platforms and get results for the simulation.

Die numerische Simulation ist ein unverzichtbares Werkzeug bei der Produktentwicklung geworden. Bereits in den frühen Phasen von Studien und Konzepten können unterschiedliche Lösungsansätze für eine Aufgabenstellung bewertet werden. In diesem Zusammenhang wird von virtuellen Prototypen gesprochen. Bei der Simulation mobiler Arbeitsmaschinen erfordert das die Einbindung des Bedieners. Die technologische Leistungsfähigkeit wird wesentlich durch die Interaktion zwischen Bediener und Maschine geprägt. Die Beschreibung des Bedieners durch mathematische Modelle ist bis zum gegenwärtigen Zeitpunkt nicht mit belastbaren Resultaten erfolgt. Die Entwicklungen im Bereich der Simulationstechnologie und der Computergrafik ermöglichen die Durchführung interaktiver Simulationen in komplexen virtuellen Welten. Damit lässt sich der Bediener direkt in die Simulation einbinden und es können zusätzliche Potenziale, wie z. B. bei der Untersuchung der Mensch-Maschine-Interaktion erschlossen werden. Durch die interaktive Simulation in Virtual-Reality-Systemen werden neue Anforderungen an die Simulationssoftware gestellt. Zur Interaktion mit dem Bediener müssen die Eingaben aus den Bedienelementen in Echtzeit verarbeitet und audiovisuelle Ausgaben generiert werden. Dabei sind neben den mathematisch-physikalischen Aspekten der Simulation auch Problemfelder wie Synchronisation, Kommunikation, Bussysteme und Computergrafik zu behandeln. Die Anpassung des Simulationssystems an unterschiedliche Aufgabenstellungen erfordert ein flexibel konfigurierbares Softwaresystem. Als Lösung dieser Aufgabenstellung wird eine Softwarearchitektur vorgestellt, welche die unterschiedlichen Problemfelder durch klar voneinander abgegrenzte Komponenten mit entsprechenden Schnittstellen behandelt. Das entstandene Softwaresystem ist flexibel und erweiterbar. Die Simulationsaufgabe wird durch die Konfiguration des Komponentensystems spezifiziert. Die entstehenden Konfigurationsdateien bilden die Anwendungslogik ab und stellen daher einen der wesentlichen Kostenfaktoren bei der Realisierung interaktiver Simulationen dar. Zur Erhöhung der Wiederverwendbarkeit bestehender Konfigurationsfragmente wird ein kompositionsbasierter Ansatz auf der Basis von Skriptsprachen gewählt. / Numerical simulation has evolved into an indispensable tool in modern product development. Even in the early design phases of studies and concepts several different approaches for one individual task can be evaluated. In this context the term virtual prototypes can be used. For effective simulation of mobile construction site machinery incorporation of the operator\'s influence is required. The technological performance of the machinery is essentially influenced by the interaction between the operator and the machine. Currently, there are no known mathematical models describing the operator\'s behaviour, which give substantiated results. The latest developments in computing technology and computer graphics facilitate interactive simulations in complex virtual worlds. This allows not only the operator to be linked to the simulation but also the investigation of additional research areas such as human-machine-interaction. The application of interactive simulation in virtual reality systems places new demands on the simulation software. Due to the interaction not only input signals from the instruments have to be processed but also audio and visual output has to be generated in real time. In addition to the mathematical and physical aspects of simulation, problems in the areas of synchronisation, communication, bus systems and computer graphics also have to be solved. The adaption of the simulation system to new tasks requires a flexible and highly configurable software system. As a response to these demands, a software architecture is presented which partitions the various problems into finite components with corresponding interfaces. The partitioning results in a flexible and extendable software system. The simulation task is specified by the configuration of the component system. The resulting configuration files reflect the application logic and therefore represent one of the main cost factors in the realisation of the interactive simulations. A composition-based approach is chosen as it raises the level of reuse of existing configuration fragments. This approach is based on scripting languages.