Show simple item record

dc.contributor.authorPower, Erik D.en_US
dc.date.accessioned2014-03-14T20:34:19Z
dc.date.available2014-03-14T20:34:19Z
dc.date.issued2001-04-20en_US
dc.identifier.otheretd-04262001-122914en_US
dc.identifier.urihttp://hdl.handle.net/10919/31927
dc.description.abstractAirbags have been saving lives in automobile crashes for many years and are now being used in helicopters. The purpose of this study was to investigate the potential for ocular injuries to helicopter pilots wearing night vision goggles when the airbag is deployed. A nonlinear finite element model of the human eye was constructed. Ocular structures never before included in finite element models of the eye, such as the fatty tissue, extraocular muscles, and bony orbit were included in this model. In addition, this model includes material properties up to rupture making the eye suitable for large deformation applications. The model was imported into Madymo and used to determine the worst-case position of a helicopter pilot wearing night vision goggles. This was evaluated as the greatest Von Mises stress in the eye when the airbag is deployed. The worst-case position was achieved by minimizing the distance between the eyes and goggles, having the occupant look directly into the airbag, and making initial contact with the airbag halfway through its full deployment. By removing the extraocular muscles, the stress sustained by the eye decreased. Simulations with both the goggles remaining fastened and breaking away from the aviator helmet were performed. Finally, placing a protective lens in front of the eyes was found to reduce the stress to the eye but increase the force experienced by the surrounding orbital bones. The finite element model of the eye proved effective at evaluating the experimental boundary conditions, and could be used in the future to evaluate impact loading on eyes that have been surgically corrected and to model the geometry of the orbital bones.en_US
dc.publisherVirginia Techen_US
dc.relation.haspartETD.pdfen_US
dc.rightsI hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to Virginia Tech or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.en_US
dc.subjectGogglesen_US
dc.subjectAirbagen_US
dc.subjectModelen_US
dc.subjectEyeen_US
dc.titleA Nonlinear Finite Element Model of the Human Eye to Investigate Ocular Injuries From Night Vision Gogglesen_US
dc.typeThesisen_US
dc.contributor.departmentMechanical Engineeringen_US
dc.description.degreeMaster of Scienceen_US
thesis.degree.nameMaster of Scienceen_US
thesis.degree.levelmastersen_US
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen_US
thesis.degree.disciplineMechanical Engineeringen_US
dc.contributor.committeechairDuma, Stefan M.en_US
dc.contributor.committeememberHerring, Ian P.en_US
dc.contributor.committeememberKress, Tyleren_US
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-04262001-122914/en_US
dc.contributor.committeecochairWest, Robert L. Jr.en_US
dc.date.sdate2001-04-26en_US
dc.date.rdate2002-04-26
dc.date.adate2001-04-26en_US


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record