Design and development of a VR system for exploration of medical data using haptic rendering and high quality visualization

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Making Games to Teach Physics and Mechanics

This survey paper introduces engineering educators to a subfield of computer graphics called physically-based animation (PBA) to advocate for collaboration in creating courses to improve student learning in STEM fields, especially in engineering. Engineering students may not realize the degree to which they can leverage their education to enter the entertainment and simulation industries. The central hypothesis of the paper is that introductory physics can be taught via PBA. The paper provides case studies that demonstrate early promise. The paper gives an overview of how “game engineers” leverage theoretical physics and mathematical concepts merged with design aesthetics to portray realistic and fun experiences, manifesting as game physics. As computing power has increased, the convergence of real and fake physics presents an opportunity to teach physics to non-game students. The field of PBA shows promise for enhancing physics education, but much work remains to determine how it may happen and the place in a college curriculum

A tool for generating three dimensional animation on computers

Ankara : The Department of Graphic Design and the Institute of Fine Arts of Bilkent Univ. , 1991.Thesis (Master's) -- Bilkent University, 1991.Includes bibliographical references leaves 31-32.In this work, a three dimensional computer animation system has been designed to be employed in schools, for the training of art students on basic three dimensional animation techniques. Puppet Theater, as we have called the system, utilizes the flexibility and effectiveness of the low-end hardware, namely IBM PC™ computers supported with Targa 16™ graphics board and gives special emphasis to user friendliness. It Is basically a software to design three dimensional objects and choreograph the object data in the computer's memory, before rendering the resulting scenery with shading methods. The system is the result of reflecting the recent advances in the field of computer graphics and pushing the potentials of the existing platform. Software is Implemented in C language, thus the code is transportable. A custom designed object oriented windowing system called WODNTW is used as the user Interface. This open windowing system supports pull-down menus, interactive buttons, scalable windows and other popular user interface elements.Türün, Cemil ŞinasiM.S

Basics of Multibody Systems: Presented by Practical Simulation Examples of Spine Models

Computer modeling is a widely used method to determine the biomechanical behavior of a system. The aim of our biomechanical multibody simulation computer modeling is to consider the characteristics of a musculoskeletal system through the use of knowledge from the fields of mechanics, anatomy, and physiology in the model in an appropriate manner, in order to obtain as accurately as possible a realistic simulation of the biomechanical behavior of the system. Various application examples of a lumbar spine model that takes the spinal structures with their specific material properties into account are presented: effects of different spine alignments in standing position, effects of overweight on the spinal biomechanics, and application possibilities of biomechanical computer models in medicine

From Fantasy to Virtual Reality: An Exploration of Modeling, Rigging and Animating Characters for Video Games

In the last few decades video games have quickly become one of the most popular forms of entertainment around the world. This can be linked to the improvement of computer systems and graphics which now allow for authentic and highly detailed computer generated characters. This project examines how these characters are modeled and developed. The examination of game characters entails a brief history of video games and their aesthetics. The foundations of character design are discussed and 3D modeling of a character is explored in detail. Finally, rigging or skeleton placement is investigated in order to animate the characters designed for this study. The result is two animated characters, which can be incorporated into several of the current and popular game engines. By the end of this paper the reader should have a fundamental understanding of how a video game character is designed, modeled, rigged, and animated

Matrix-based Parameterizations of Skeletal Animated Appearance

Alors que le rendu réaliste gagne de l’ampleur dans l’industrie, les techniques à la fois photoréalistes et basées sur la physique, complexes en terme de temps de calcul, requièrent souvent une étape de précalcul hors-ligne. Les applications en temps réel, comme les jeux vidéo et la réalité virtuelle, se basent sur des techniques d’approximation et de précalcul pour atteindre des résultats réalistes. L’objectif de ce mémoire est l’investigation de différentes paramétrisations animées pour concevoir une technique d’approximation de rendu réaliste en temps réel. Notre investigation se concentre sur le rendu d’effets visuels appliqués à des personnages animés par modèle d’armature squelettique. Des paramétrisations combinant des données de mouvement et d’apparence nous permettent l’extraction de paramètres pour le processus en temps réel. Établir une dépendance linéaire entre le mouvement et l’apparence est ainsi au coeur de notre méthode. Nous nous concentrons sur l’occultation ambiante, où la simulation de l’occultation est causée par des objets à proximité bloquant la lumière environnante, jugée uniforme. L’occultation ambiante est une technique indépendante du point de vue, et elle est désormais essentielle pour le réalisme en temps réel. Nous examinons plusieurs paramétrisations qui traitent l’espace du maillage en fonction de l’information d’animation par squelette et/ou du maillage géométrique. Nous sommes capables d’approximer la réalité pour l’occultation ambiante avec une faible erreur. Notre technique pourrait également être étendue à d’autres effets visuels tels le rendu de la peau humaine (diffusion sous-surface), les changements de couleur dépendant du point de vue, les déformations musculaires, la fourrure ou encore les vêtements.While realistic rendering gains more popularity in industry, photorealistic and physically- based techniques often necessitate offline processing due to their computational complexity. Real-time applications, such as video games and virtual reality, rely mostly on approximation and precomputation techniques to achieve realistic results. The objective of this thesis is to investigate different animated parameterizations in order to devise a technique that can approximate realistic rendering results in real time. Our investigation focuses on rendering visual effects applied to skinned skeletonbased characters. Combined parameterizations of motion and appearance data are used to extract parameters that can be used in a real-time approximation. Trying to establish a linear dependency between motion and appearance is the basis of our method. We focus on ambient occlusion, a simulation of shadowing caused by objects that block ambient light. Ambient occlusion is a view-independent technique important for realism. We consider different parameterization techniques that treat the mesh space depending on skeletal animation information and/or mesh geometry. We are able to approximate ground-truth ambient occlusion with low error. Our technique can also be extended to different visual effects, such as rendering human skin (subsurface scattering), changes in color due to the view orientation, deformation of muscles, fur, or clothe

Animated surfaces in physically-based simulation

Physics-based animation has become a ubiquitous element in all application areas of computer animation, especially in the entertainment sector. Animation and feature films, video games, and advertisement contain visual effects using physically-based simulation that blend in seamlessly with animated or live-action productions. When simulating deformable materials and fluids, especially liquids, objects are usually represented by animated surfaces. The visual quality of these surfaces not only depends on the actual properties of the surface itself but also on its generation and relation to the underlying simulation. This thesis focuses on surfaces of cloth simulations and fluid simulations based on Smoothed Particle Hydrodynamics (SPH), and contributes to improving the creation of animations by specifying surface shapes, modeling contact of surfaces, and evaluating surface effects of fluids. In many applications, there is a reference given for a surface animation in terms of its shape. Matching a given reference with a simulation is a challenging task and similarity is often determined by visual inspection. The first part of this thesis presents a signature for cloth animations that captures characteristic shapes and their temporal evolution. It combines geometric features with physical properties to represent accurately the typical deformation behavior. The signature enables calculating similarities between animations and is applied to retrieve cloth animations from collections by example. Interactions between particle-based fluids and deformable objects are usually modeled by sampling the deformable objects with particles. When interacting with cloth, however, this would require resampling the surface at large planar deformations and the thickness of cloth would be bound to the particle size. This problem is addressed in this thesis by presenting a two-way coupling technique for cloth and fluids based on the simulation mesh of the textile. It allows robust contact handling and intuitive control of boundary conditions. Further, a solution for intersection-free fluid surface reconstruction at contact with thin flexible objects is presented. The visual quality of particle-based fluid animation highly depends on the properties of the reconstructed surface. An important aspect of the reconstruction method is that it accurately represents the underlying simulation. This thesis presents an evaluation of surfaces at interfaces of SPH simulations incorporating the connection to the simulation model. A typical approach in computer graphics is compared to surface reconstruction used in material sciences. The behavior of free surfaces in fluid animations is highly influenced by surface tension. This thesis presents an evaluation of three types of surface tension models in combination with different pressure force models for SPH to identify the individual characteristics of these models. Systematic tests using a set of benchmark scenes are performed to reveal strengths and weaknesses, and possible areas of applications.Physikalisch basierte Animationen sind ein allgegenwärtiger Teil in jeglichen Anwendungsbereichen der Computeranimation, insbesondere dem Unterhaltungssektor. Animations- und Spielfilme, Videospiele und Werbung enthalten visuelle Effekte unter Verwendung von physikalisch basierter Simulation, die sich nahtlos in Animations- oder Realfilme einfügen. Bei der Simulation von deformierbaren Materialien und Fluiden, insbesondere Flüssigkeiten, werden die Objekte gewöhnlich durch animierte Oberflächen dargestellt. Die visuelle Qualität dieser Oberflächen hängt nicht nur von den Eigenschaften der Fläche selbst ab, sondern auch von deren Erstellung und der Verbindung zu der zugrundeliegenden Simulation. Diese Dissertation widmet sich Oberflächen von Textil- und Fluidsimulationen mit der Methode der Smoothed Particle Hydrodynamics (SPH) und leistet einen Beitrag zur Verbesserung der Erstellung von Animationen durch die Beschreibung von Oberflächenformen, der Modellierung von Kontakt von Oberflächen und der Evaluierung von Oberflächeneffekten von Fluiden. In vielen Anwendungen gibt es eine Referenz für eine Oberflächenanimation, die ihre Form beschreibt. Das Abgleichen einer Referenz mit einer Simulation ist eine große Herausforderung und die Ähnlichkeit wird häufig visuell überprüft. Im ersten Teil der Dissertation wird eine Signatur für Textilanimationen vorgestellt, die charakteristische Formen und ihre zeitliche Veränderung erfasst. Sie ist eine Kombination aus geometrischen Merkmalen und physikalischen Eigenschaften, um das typische Deformationsverhalten genau zu repräsentieren. Die Signatur erlaubt es, Ähnlichkeiten zwischen Animationen zu berechnen, und wird angewendet, um Textilanimationen aus Kollektionen anhand eines Beispiels aufzufinden. Interaktionen zwischen partikelbasierten Fluiden und deformierbaren Objekten werden gewöhnlich durch das Abtasten des deformierbaren Objekts mit Partikeln modelliert. Bei der Interaktion mit Textilien würde dies jedoch ein neues Abtasten bei großen planaren Deformation erfordern und die Stärke des Textils wäre an die Partikelgröße gebunden. Mit diesem Problem befasst sich diese Dissertation und stellt eine Technik für die wechselseitige Kopplung zwischen Textilien und Fluiden vor, die auf dem Simulationsnetz des Textils beruht. Diese erlaubt eine robuste Kontaktbehandlung und intuitive Kontrolle von Randbedingungen. Des Weiteren wird ein Lösungsansatz für eine durchdringungsfreie Oberflächenrekonstruktion beim Kontakt mit dünnen flexiblen Objekten präsentiert. Die visuelle Qualität von partikelbasierten Fluidanimationen hängt stark von den Eigenschaften der rekonstruierten Oberfläche ab. Wichtig bei Rekonstruktionsmethoden ist, dass sie die zugrundeliegende Simulation genau repräsentieren. Die Dissertation präsentiert eine Evaluierung von Oberflächen an Grenzflächen, die den Zusammenhang zum Simulationsmodell miteinbezieht. Ein typischer Ansatz aus der Computergrafik wird mit der Oberflächenrekonstruktion in der Werkstoffkunde verglichen. Das Verhalten von freien Oberflächen in Fluidanimationen wird stark von der Oberflächenspannung beeinflusst. In dieser Dissertation wird eine Evaluierung von drei Oberflächenspannungsmodellen in Kombination mit verschiedenen Druckmodellen für SPH präsentiert, um die Charakteristika der jeweiligen Modelle zu identifizieren. Es werden systematische Tests mit Hilfe von Benchmark-Tests durchgeführt, um Stärken, Schwächen und mögliche Anwendungsbereiche deutlich zu machen