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dc.contributor.advisorHu, Yaoping
dc.contributor.authorWidmer, Antoine
dc.date.accessioned2012-07-23T22:19:41Z
dc.date.available2012-11-13T08:01:18Z
dc.date.issued2012-07-23
dc.date.submitted2012en
dc.identifier.citationWidmer, A. (2012). Approach to ease design criteria of a real-time model used in a VR training system considering constraints of human perception (Unpublished doctoral thesis). University of Calgary, Calgary, AB. doi:10.11575/PRISM/24980en_US
dc.identifier.urihttp://hdl.handle.net/11023/130
dc.description.abstractVirtual reality (VR) systems have potential of contributing to the training of medical students in a variety of procedures. This thesis focuses on a design issue related to developing VR training systems for soft tissue (e.g., breast phantom) palpation. In such a VR system, it is paramount to provide a real-time model that simulates physical behavior of an actual breast phantom. However, it is difficult to design such a real-time model with high accuracy due to time and physical constraints. To mitigate this difficulty, I consider constraints of human perception which is insensitive to small discrepancies of objects during real-time interaction. Such consideration could aid to relax design criteria of the real-time model by achieving its accuracy at a certain degree while keeping human perception of object softness unchanged. Therefore, I take a two-step approach to determine visual and haptic (pertinent to force feedback) discrepancies tolerable for this human perception. In the first step, an evaluation method is developed to compute discrepancies of the real-time model for visual displacement and force feedback, compared to its finite element method counterpart featuring physical parameters of a breast phantom. The computation uses statistical analyses which like human perception are insensitive to small discrepancies of datasets. In the second step, two studies are performed to examine the constraints of human perception. The first study reexamined raw data from my MSc work to understand the effect of three popular alignments between a visual display and a haptic device on the human perception of object softness. This study serves to select an alignment producing the least perceptual illusion and physical workload for palpation. Using the evaluation method and the selected alignment, the second study investigates the effect of different discrepancies on the human perception of object softness. It is observed that this perception is insensitive to small discrepancies up to a threshold of 11.0% and 6.3% for visual displacement and force feedback, respectively. This indicates that a real-time model yielding discrepancies of visual displacement and force feedback below their respective thresholds could be sufficient for simulating a soft tissue (such as a breast phantom) during palpation.en_US
dc.language.isoeng
dc.rightsUniversity of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.
dc.subjectEngineering--Electronics and Electrical
dc.subject.classificationVirtual Realityen_US
dc.subject.classificationHaptic feedbacken_US
dc.subject.classificationHuman perceptionen_US
dc.titleApproach to ease design criteria of a real-time model used in a VR training system considering constraints of human perception
dc.typedoctoral thesis
dc.publisher.facultyGraduate Studies
dc.publisher.institutionUniversity of Calgaryen
dc.identifier.doihttp://dx.doi.org/10.11575/PRISM/24980
thesis.degree.nameDoctor of Philosophy
thesis.degree.namePhD
thesis.degree.disciplineElectrical and Computer Engineering
thesis.degree.grantorUniversity of Calgary
atmire.migration.oldid191
dc.publisher.placeCalgaryen


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