Smart material electrohydrostatic actuator for intelligent transportation systems

Bibliographic Details
Main Author:	Rupinsky, Michael J.
Language:	English
Published:	The Ohio State University / OhioLINK 2006
Subjects:	Mechanical Engineering
Online Access:	http://rave.ohiolink.edu/etdc/view?acc_num=osu1391701972

id	ndltd-OhioLink-oai-etd.ohiolink.edu-osu1391701972
record_format	oai_dc
spelling	ndltd-OhioLink-oai-etd.ohiolink.edu-osu13917019722021-08-03T06:21:33Z Smart material electrohydrostatic actuator for intelligent transportation systems Rupinsky, Michael J. Mechanical Engineering <p>Future intelligent transportation systems require actuation systems that are light- weight, compact and have a large power density. Due to their solid-state operation, fast frequency response, and high power-to-weight ratio, electrohydrostatic actuators (EHAs) based on smart materials are attractive as a replacement for conventional hydraulic actuators. Unlike conventional hydraulic systems, EHAs use smart mate¬rial pumps which are driven electrically and integrated within the EHA rather than being mechanically connected to the vehicle’s engine, thus precluding the need for ac¬cessory gear boxes and plumbing throughout the vehicle. This also permits the EHA to achieve much higher frequency responses, much lower overall power consumption, and increased reliability. The automotive and aerospace industries currently are the leading sectors in EHA research. Specific automotive uses include active suspension concepts, fly-by-wire steering and braking; aircraft uses include landing gear actuation and adaptive morphing of wings for advanced aerodynamic control.</p><p>A smart material deforms and changes its properties when exposed to external fields, for example electric fields (piezoelectric materials) or magnetic fields (magnetostrictive materials). Since smart materials produce small-stroke, large-force, high-frequency motion output in response to external fields, methods for transmitting small vibrations into large deformations and forces are needed. This document is focused on the development of a smart material-based pump for EHAs in which the mechanical vibrations produced by a magnetostrictive alloy, terbium-iron-dysprosium, are recti¬fied by means of diode-type mechanical reed valves. A prototype pump is designed and constructed. Measurements conducted on this system demonstrate the ability of the reed valves to effectively rectify the oscillatory pressure pulses created by the magnetostrictive material and create unidirectional fluid flow. A maximum blocked pressure differential of 1100 psi is achieved with a power consumption of 84 W. A dynamic system model of the magnetostrictive pump with an attached hydraulic ac¬tuator is presented. The model is developed by using a lumped parameter analysis on the hydraulic circuit and using Newton’s laws to couple the hydraulic and the me¬chanical domains. Coupling between mechanical and electrical domains is achieved by formulating electroacoustic transduction equations. Coupled differential equations of the system level model are written in state space form and solved numerically in MATLAB. The solver assumes a linear system for each time step and utilizes the values at previous times as initial conditions in order to march through time. The model can be easily modified in order to accurately model testing of the pump. The dynamic system model aids in validating the device operation and gives insight into future design modifications aimed at increasing the pressure output. Calculation of mechanical and electrical impedances allows analysis of the effect of hydraulic loading on pump operation.</p> 2006 English text The Ohio State University / OhioLINK http://rave.ohiolink.edu/etdc/view?acc_num=osu1391701972 http://rave.ohiolink.edu/etdc/view?acc_num=osu1391701972 unrestricted This thesis or dissertation is protected by copyright: all rights reserved. It may not be copied or redistributed beyond the terms of applicable copyright laws.
collection	NDLTD
language	English
sources	NDLTD
topic	Mechanical Engineering
spellingShingle	Mechanical Engineering Rupinsky, Michael J. Smart material electrohydrostatic actuator for intelligent transportation systems
author	Rupinsky, Michael J.
author_facet	Rupinsky, Michael J.
author_sort	Rupinsky, Michael J.
title	Smart material electrohydrostatic actuator for intelligent transportation systems
title_short	Smart material electrohydrostatic actuator for intelligent transportation systems
title_full	Smart material electrohydrostatic actuator for intelligent transportation systems
title_fullStr	Smart material electrohydrostatic actuator for intelligent transportation systems
title_full_unstemmed	Smart material electrohydrostatic actuator for intelligent transportation systems
title_sort	smart material electrohydrostatic actuator for intelligent transportation systems
publisher	The Ohio State University / OhioLINK
publishDate	2006
url	http://rave.ohiolink.edu/etdc/view?acc_num=osu1391701972
work_keys_str_mv	AT rupinskymichaelj smartmaterialelectrohydrostaticactuatorforintelligenttransportationsystems
_version_	1719435353612353536

Smart material electrohydrostatic actuator for intelligent transportation systems

Similar Items