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dc.contributor.advisorYounis, Mohammad I.
dc.contributor.authorHajjaj, Amal
dc.date.accessioned2019-05-13T13:52:45Z
dc.date.available2020-05-13T00:00:00Z
dc.date.issued2019-05
dc.identifier.citationHajjaj, A. (2019). Electrothermally Tuned and Electrostatically Actuated MEMS Resonators: Dynamics and Applications. KAUST Research Repository. https://doi.org/10.25781/KAUST-E9Y73
dc.identifier.doi10.25781/KAUST-E9Y73
dc.identifier.urihttp://hdl.handle.net/10754/652869
dc.description.abstractThe objective of this thesis is to present a theoretical and experimental investigation of the dynamics of micro and nano-electromechanical systems electrothermally tuned and electrostatically actuated, and explore their potential for practical applications. The first part of the dissertation presents the tuning of the frequency of clamped-clamped micro and nano-resonators, straight and curved. These resonators are electrothermally or electrostatically tuned. The effect of geometric parameters on the frequency variation is investigated experimentally and theoretically using a reduced order model based on the Euler-Bernoulli beam theory. High tunability is demonstrated for micro and nano beams, straight and initially curved. The second part discusses the dynamical behavior of a curved (arch) beam electrothermally tuned and electrostatically actuated. We show that the first resonance frequency increases up to twice its fundamental value and the third resonance frequency decreases until getting very close to the first resonance frequency triggering the veering phenomenon. We study experimentally and analytic ally, using the Galerkin procedure, the dynamic behavior of the arch beam. Next, upon changing the electrothermal voltage, the second symmetric natural frequency of the arch is adjusted to near twice, three times, and four times the fundamental natural frequency. This gives rise to a potential two-to-one, three-to-one, and four-to-one autoparametric resonances between the two modes. These resonances are demonstrated experimentally and theoretically. The third part of the dissertation is concerned with the incorporation of the electrothermally tuned and electrostatically actuated microresonators into potential applications: filtering and sensing. First, we experimentally prove an exploitation of the nonlinear softening, hardening, and veering phenomena of an arch beam, to demonstrate a flat, wide, and tunable bandwidth and center frequency by controlling the electrothermal actuation voltage. Second, a pressure sensor based on the convective cooling of the air surrounding an electrothermally heated resonant bridge is demonstrated experimentally. The concept is demonstrated using both straight and arch microbeam resonators driven and sensed electrostatically. The change in the surrounding pressure is shown to be accurately tracked by monitoring the change in the resonance frequency of the structure.
dc.language.isoen
dc.subjectelectrothermal
dc.subjectelectrostatic
dc.subjectMEMS
dc.subjectMode Coupling
dc.subjectTunability
dc.subjectFilter / sensing
dc.titleElectrothermally Tuned and Electrostatically Actuated MEMS Resonators: Dynamics and Applications
dc.typeDissertation
dc.contributor.departmentPhysical Science and Engineering (PSE) Division
dc.rights.embargodate2020-05-13
thesis.degree.grantorKing Abdullah University of Science and Technology
dc.contributor.committeememberLaleg-Kirati, Taous-Meriem
dc.contributor.committeememberFarooq, Aamir
dc.contributor.committeememberAmabili, Marco
thesis.degree.disciplineMechanical Engineering
thesis.degree.nameDoctor of Philosophy
dc.rights.accessrightsAt the time of archiving, the student author of this dissertation opted to temporarily restrict access to it. The full text of this dissertation became available to the public after the expiration of the embargo on 2020-05-13.
refterms.dateFOA2020-05-13T00:00:00Z
kaust.request.doiyes


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