{"510841":{"#nid":"510841","#data":{"type":"event","title":"PhD Dissertation Defense by Jeremy Hill","body":[{"value":"\u003Cp\u003E\u003Cstrong\u003ECommittee:\u003C\/strong\u003E\u003C\/p\u003E\u003Cp\u003EDr. Robert Braun (Advisor), School of Aerospace Engineering, Georgia Tech\u003C\/p\u003E\u003Cp\u003EDr. Julian Rimoli,\u0026nbsp;School of Aerospace Engineering, Georgia Tech\u003C\/p\u003E\u003Cp\u003EDr. Graeme Kennedy, School of Aerospace Engineering, Georgia Tech\u003C\/p\u003E\u003Cp\u003EDr. Anthony Calomino, NASA Langley Research Center\u003Cbr \/\u003E Dr. Christopher Tanner, NASA Jet Propulsion Laboratory\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003EAbstract:\u003C\/strong\u003E\u003C\/p\u003E\u003Cp\u003EInflatable Aerodynamic Decelerators (IADs) are a candidate technology NASA began investigating in the late 1960\u2019s. \u0026nbsp;Compared to supersonic parachutes, IADs represent a decelerator option capable of operating at higher Mach numbers and dynamic pressures. \u0026nbsp;IADs have seen a resurgence in interest from the Entry, Descent, and Landing (EDL) community in recent years. \u0026nbsp;The NASA Space Technology Roadmap (STR) highlights EDL systems, as well as, Materials, Structures, Mechanical Systems, and Manufacturing (MSMM) as key Technology Areas for development in the future; recognizing deployable decelerators, flexible material systems, and computational design of materials as essential disciplines for development. \u0026nbsp;This investigation develops a multi-scale flexible material modeling approach that enables efficient high-fidelity IAD design and a critical understanding of the new materials required for robust and cost effective qualification methods. \u0026nbsp;The approach combines understanding of the fabric architecture, analytical modeling, numerical simulations, and experimental data. \u0026nbsp;This work identifies an efficient method that is as simple and as fast as possible for determining IAD material characteristics while not utilizing complicated or expensive research equipment. \u0026nbsp;This investigation also recontextualizes an existing mesomechanical model through validation for structures pertaining to the analysis of IADs. \u0026nbsp;In addition, corroboration and elaboration of this model is carried out by evaluating the effects of varying input parameters. \u0026nbsp;Finally, the present investigation presents a novel method for numerically determining mechanical properties. \u0026nbsp;A sub-scale section that captures the periodic pattern in the material (unit cell) is built. \u0026nbsp;With the unit cell, various numerical tests are performed. \u0026nbsp;The effective nonlinear mechanical stiffness matrix is obtained as a function of elemental strains through correlating the unit cell force-displacement results with a four node membrane element of the same size. \u0026nbsp;Numerically determined properties are validated for relevant structures. \u0026nbsp;Optical microscopy is used to capture the undeformed geometry of the individual yarns.\u003C\/p\u003E","summary":null,"format":"limited_html"}],"field_subtitle":"","field_summary":"","field_summary_sentence":[{"value":"Mechanical Property Determination for Flexible Material Systems"}],"uid":"27690","created_gmt":"2016-03-08 16:00:12","changed_gmt":"2016-10-08 02:16:55","author":"Jacquelyn Strickland","boilerplate_text":"","field_publication":"","field_article_url":"","field_event_time":{"event_time_start":"2016-03-16T16:00:00-04:00","event_time_end":"2016-03-16T18:00:00-04:00","event_time_end_last":"2016-03-16T18:00:00-04:00","gmt_time_start":"2016-03-16 20:00:00","gmt_time_end":"2016-03-16 22:00:00","gmt_time_end_last":"2016-03-16 22:00:00","rrule":null,"timezone":"America\/New_York"},"extras":[],"groups":[{"id":"221981","name":"Graduate Studies"}],"categories":[],"keywords":[{"id":"119191","name":"PhD Dissertation Defense"}],"core_research_areas":[],"news_room_topics":[],"event_categories":[{"id":"1788","name":"Other\/Miscellaneous"}],"invited_audience":[{"id":"78771","name":"Public"}],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[],"email":[],"slides":[],"orientation":[],"userdata":""}}}