Stroke is the third largest cause of death in Sweden. In 2005, 30.000 people in Sweden suffered from a stroke. The consequences of a stroke varies, but the most common disability among stroke survivors is abnormal reaching movements, which is the primer reason for limitations in activities of everyday living. Rehabilitation is essential in order to get back to everyday life. Physical assistance (or guidance) is used in rehabilitation by physiotherapists and occupational therapists to help a patient through a dicult movement for example. Today, this guidance is limited to be performed by medical personnel. With the technology of virtual environments (VE) and haptics – force feedback from a computer – there is a possibility to create guidance which does not need medical personnel. This should be used as a complement to the traditional therapy. The intention of this work is to create an invisible guidance eld, which should guide a patient's hand to a desired movement pattern, i.e. aid the patient to perform a task in a virtual environment with haptics. This guidance is added to an already existing assessment tool, which is a part of the Curictus AB rehabilitation system. The guiding system is implemented using SenseGraphics AB's H3D API. To create the feeling of guidance and a guidance eld, the Volume Haptics Toolkit, developed by Dr. Karljohan Lundin Palmerius at Linköping University, was used. The basic idea of the algorithm is to calculate an orientation vector, for every position, in which direction the guidance should guide the patient. The guidance, which is generated via a haptic device, is adaptive to the patient's movements and always guides the patient towards the target in a smooth trajectory. / Stroke är den tredje största dödsorsaken i Sverige. Under år 2005 ck 30.000 svenskar en stroke. Följderna av en stroke kan variera, men vanligast är försämrad rörlighet i en sida av kroppen, vilket också är den främsta orsaken till begränsningar i dagliga aktiviteter för  strokepatienter. Rehabilitering är nödvändig för att kunna återkomma till sitt vanliga liv. Fysisk guidning är något som sjukgymnaster och arbetsterapeuter använder sig av i rehabiliteringen för att hjälpa en patient t.ex. genom en svår rörelse. Denna hjälp är något som idag är begränsad till medicinsk personal. Med teknologi som virtuella miljöer och haptik – kraftåterkoppling från en dator – finns det möjligheter att skapa guidning som inte kräver medicinsk personal. Detta ska fungera som ett komplement till den traditionella rehabiliteringen. Avsikten med det här arbetet är att skapa ett osynligt guidningsfält som ska guida en patients hand till ett önskat rörelsemönster, d.v.s. hjälpa patienten att utföra en övning i en virtuell miljö med haptik. Denna guidning ska läggas in i ett redan existerande utvärderingsverktyg, som nns i Curictus ABs rehabiliteringssystem. Guidningssystemet är implementerat i SenseGraphics ABs H3D API. För att skapa känslan av guidning och guidningsfältet användes the Volume Haptics Toolkit, utvecklat av dr. Karljohan Lundin Palmerius vid Linköpings Universitet. Algoritmen är byggd på att för varje position, beräkna en riktningsvektor dit guidningen ska guida patienten via en haptikenhet. Guidningen, som anpassas efter patientens rörelser, guidar hela tiden mot målet i en mjuk rörelsebana.

The introduction of digital media into the working practice of artists has produced challenges previously unknown to the field of art. This inquiry follows an atypical model of artist-driven research derived from disciplines such as social science and education. Here, an artwork functions as a model that is self-reflective, integrating methodologies in a form that benefits art and science. Using Naturalistic Inquiry, including semi-structured interviews of fifteen participants, the work illustrates a process of creation, analysis and evaluation that places the values of the artist on equal footing with the needs of science. Recently, artists have begun using video game engines as a tool to produce 3D navigable spaces. Using the hybrid video game/installation Playas: Homeland Mirage as a case study, this research examines the impact of technology on the artwork and identifies a number of key issues related to the function of critical reflection in this environment. Rules-of-play were a fundamental pre-requisite to the stimulation of critically reflective experience. The human interface with software and hardware was also a primary factor in reflective experience. Based on participant evaluation and observation, the interface was altered in response to its effect on critical reflection, illustrating how choices in this area impact aesthetic experience. Those with experience in visual art were more likely to engage the work in a critically reflective manner than seasoned video game players who tended to be more interested in scoring and winning. These findings and others inform our understanding of the stimulation of critical reflection in immersive environments and show how we can sensitively integrate technology with meaningful evaluative methods. By repurposing a video game in this manner, we learn about the nature of the video game and the nature of art. This research enables artists to gain a better understanding of the medium to more fully integrate technology within a meaningful practice. Conversely, other fields will benefit from a better understanding of the stimulation of meaning in immersive spaces and gain a comprehensive view of a work that strives to contribute to our culture on a deeper level than as simple entertainment. Ultimately, more fully understanding critical reflection in virtual environments will enable us to create enriched experiences that transcend space to create “real” or “virtual” place.

As the progress of computer, virtual reality has become a more and more widespread technology and is applied extensively in entertainment, training, or medical science. To increase the interaction and reality of the virtual technology, the development of haptic feedback improves rapidly in recent years. This paper focuses on judgment existing collision detection algorithms, virtual wall models, and friction models from the view point of man-machine interface. A virtual environment interface with force feedback by using a joystick for computer game as a haptic device is established. A virtual environment is also built by employing the DirectX, a 3D computer graphic software developed by Microsoft Corp. Three virtual wall models are compared and four operational experiments are conducted to explore the influence of force feedback on operation task in virtual environment.

When evaluating the benefits of the artificial reefs, the generally is performed by sending divers or using Remotely Operated Vehicles (ROV). But to do the observation work, the deep sea is too dangerous for human being to work longer time, and ROV has no capable navigation system. So underwater survey became difficulty. The thesis integrates LXT Tracking System, Global Positioning System, Motion Sensor, Gyro Compass and the ROV original sensors such as : pressure sensor and magnetic compass to resolve the navigation problem of ROV, together with the high-density data of Multibeam echo sounder to rebuild the status of the seabed and artificial reefs. The thesis tries to apply the technology of Virtual Reality (VR) in ROV to being the interface. The results demonstrate the VR interface can display the position of ROV in three-dimensional space actually. And it can show the position of ROV navigation and warning message in real time when sailing. So the VR Navigation System will improve the ability of operating ROV greatly.

The enforcement of reusability and shareability of products or components based on new technology standards for simulation and modeling is of paramount importance. In this thesis we first utilize DMSO HLA as the basic fundamental to design a customization environment for Web-based modeling and simulation. The environment is able to offer the interoperability framework between a broad spectrum of simulation paradigms, including both real-time and logical time models and to support a huge number of participants. To fulfill the goal we proposed three main tasks to be done. First, we proposed the mechanism to reduce the communication overhead and to balance the information consistency among large participants by incorporating a three-level control mechanism and Dynamic Filtering Strategy (DFS) within HLA RTI. In the second task, we proposed a load balancing algorithm to efficiently utilize the resource over the network environment. At the last task we use Java 3D to build a virtual reality application on the environment.

<p>Denna rapport behandlar skillnader i bland annat visuell information (som olika djupledtrådar) vilka kan ha betydelse för den visuella upplevelsen och inverkan på till exempel precisionsbedömningar gällande avstånd i både virtuella och verkliga miljöer.</p><p>Rapporten lyfter fram tre olika presentationstekniker som presenterar visuell information i olika utsträckning. Två av presentationsteknikerna, Desktop och CUBE, presenterar två virtuella miljöer. Den tredje presentationstekniken, Verklig, presenterar en verklig miljö. De tre presentationsteknikerna ställs mot varandra i en undersökning gällande eventuella skillnader i precisionsbedömningar (avståndsbedömningar mellan och på olika objekt). Resultatet visar att det föreligger signifikanta skillnader vad gäller precisionsbedömningar mellan den virtuella presentationstekniken Desktop och Verklig samt mellan den virtuella presentationstekniken CUBE och Verklig. Däremot föreligger ingen signifikant skillnad vad gäller precisionsbedömningar mellan de båda virtuella presentationsteknikerna Desktop och CUBE.</p>

Originally presented as the author's Thesis--Universität Magdeburg, 2007. / Includes bibliographical references.

Thesis (M.S.)--Mississippi State University. Department of Electrical and Computer Engineering. / Title from title screen. Includes bibliographical references.

Thesis (M.S. in Computer Science)--Naval Postgraduate School, June 2004. / Thesis advisor(s): Rudolph Darken, Joseph A. Sullivan. Includes bibliographical references (p. 103-104). Also available online.

Thesis (Ph. D.)--College of Computing, Georgia Institute of Technology, 2004. Directed by Larry F. Hodges. / Vita. Includes bibliographical references (leaves 112-115).