Variable impedance energy dissipation on the micro-scale : field responsive fluids in novel geometries

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2006.

Bibliographic Details
Main Author: Griffin, Ryan A
Other Authors: Neville Hogan.
Format: Thesis
Language:eng
Published: Massachusetts Institute of Technology 2007
Subjects:
Online Access:http://hdl.handle.net/1721.1/38272
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author Griffin, Ryan A
author2 Neville Hogan.
author_facet Neville Hogan.
Griffin, Ryan A
author_sort Griffin, Ryan A
collection MIT
description Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2006.
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spelling mit-1721.1/382722019-04-11T07:53:02Z Variable impedance energy dissipation on the micro-scale : field responsive fluids in novel geometries Griffin, Ryan A Neville Hogan. Massachusetts Institute of Technology. Dept. of Mechanical Engineering. Massachusetts Institute of Technology. Dept. of Mechanical Engineering. Mechanical Engineering. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2006. Includes bibliographical references (leaves 187-189). The aim of this thesis was to further characterize the effectiveness of field responsive fluids (FRFs) in geometries pertinent to the soldier and to examine the effects of specific geometric and kinematic parameters, including patterned surface geometry, electrode gap distance, and normal force on the performance of homogeneous ERF composites. Field responsive fluid composites designed for variable impedance energy absorption incorporated electrorheological fluid (ERF) and shear-thickening fluid (STF) in novel geometries to absorb compressive and tensile/shear forces. ER and ST fluids change their apparent viscosity in the presence of elevated electric and shear fields, respectively, and the magnitude of this effect can be adjusted using the magnitude of the input field, allowing variable impedance operation. Several test fixtures were developed to test these novel FRF composites. A compression apparatus was designed and constructed to test STF-filled foam over a range of strain rates not previously examined in the literature. Silicon-based microchannel devices with etched features on the order of 100 pm and etch depths of 7-90 pm were fabricated to test homogeneous ER fluids in small electrode gaps. (cont.) Tests using these silicon devices allowed creation of 5 kV/mm (5 V/pm) electric fields across electrode gaps as small as 20 pm, with increases of measured shear force as high as 350% from no electric field to full 5 kV/mm operation. Production of these devices in bulk using established silicon processing techniques was demonstrated, and factors affecting the manufacture of these devices were investigated. by Ryan A. Griffin. S.M. 2007-08-03T18:24:23Z 2007-08-03T18:24:23Z 2006 2006 Thesis http://hdl.handle.net/1721.1/38272 151224501 eng M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission. http://dspace.mit.edu/handle/1721.1/7582 189 leaves application/pdf Massachusetts Institute of Technology
spellingShingle Mechanical Engineering.
Griffin, Ryan A
Variable impedance energy dissipation on the micro-scale : field responsive fluids in novel geometries
title Variable impedance energy dissipation on the micro-scale : field responsive fluids in novel geometries
title_full Variable impedance energy dissipation on the micro-scale : field responsive fluids in novel geometries
title_fullStr Variable impedance energy dissipation on the micro-scale : field responsive fluids in novel geometries
title_full_unstemmed Variable impedance energy dissipation on the micro-scale : field responsive fluids in novel geometries
title_short Variable impedance energy dissipation on the micro-scale : field responsive fluids in novel geometries
title_sort variable impedance energy dissipation on the micro scale field responsive fluids in novel geometries
topic Mechanical Engineering.
url http://hdl.handle.net/1721.1/38272
work_keys_str_mv AT griffinryana variableimpedanceenergydissipationonthemicroscalefieldresponsivefluidsinnovelgeometries