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dc.contributor.authorRaghavan, Brijeshen
dc.date.accessioned2014-03-14T20:09:32Zen
dc.date.available2014-03-14T20:09:32Zen
dc.date.issued2009-03-30en
dc.identifier.otheretd-04132009-143933en
dc.identifier.urihttp://hdl.handle.net/10919/26829en
dc.description.abstractHigh aspect-ratio flying wing configurations designed for high altitude, long endurance missions are characterized by high flexibility, leading to significant static aeroelastic deformation in flight, and coupling between aeroelasticity and flight dynamics. As a result of this coupling, an integrated model of the aeroelasticity and flight dynamics has to be used to accurately model the dynamics of the flexible flying wing. Such an integrated model of the flight dynamics and the aeroelasticity developed by Patil and Hodges is reviewed in this dissertation and is used for studying the unique flight dynamics of high aspect-ratio flexible flying wings. It was found that a rigid body configuration that accounted for the static aeroelastic deformation at trim captured the predominant flight dynamic characteristics shown by the flexible flying wing. Moreover, this rigid body configuration was found to predict the onset of dynamic instability in the flight dynamics seen in the integrated model. Using the concept of the mean axis, a six degree-of-freedom reduced order model of the flight dynamics is constructed that minimizes the coupling between rigid body modes and structural dynamics while accounting for the nonlinear static aeroelastic deformation of the flying wing. Multi-step nonlinear dynamic inversion applied to this reduced order model is coupled with a nonlinear guidance law to design a flight controller for path following. The controls computed by this flight controller are used as inputs to a time-marching simulation of the integrated model of aeroelasticity and flight dynamics. Simulation results presented in this dissertation show that the controller is able to successfully follow both straight line and curved ground paths while maintaining the desired altitude. The controller is also shown to be able to handle an abrupt change in payload mass while path-following. Finally, the equations of motion of the integrated model were non-dimensionalized to identify aeroelastic parameters for optimization and design of high aspect-ratio flying wings.en
dc.publisherVirginia Techen
dc.relation.haspartRaghavan_Dissertation.pdfen
dc.rightsIn Copyrighten
dc.rights.urihttp://rightsstatements.org/vocab/InC/1.0/en
dc.subjectFlexible high aspect-ratio flying-wingsen
dc.subjectflight dynamicsen
dc.subjectflight controlen
dc.titleFlight Dynamics and Control of Highly Flexible Flying-Wingsen
dc.typeDissertationen
dc.contributor.departmentAerospace and Ocean Engineeringen
dc.description.degreePh. D.en
thesis.degree.namePh. D.en
thesis.degree.leveldoctoralen
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen
thesis.degree.disciplineAerospace and Ocean Engineeringen
dc.contributor.committeechairPatil, Mayuresh J.en
dc.contributor.committeememberMcCue-Weil, Leigh S.en
dc.contributor.committeememberWoolsey, Craig A.en
dc.contributor.committeememberKapania, Rakesh K.en
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-04132009-143933/en
dc.date.sdate2009-04-13en
dc.date.rdate2009-04-22en
dc.date.adate2009-04-22en


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