Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 30 for “"vibration damping"”.
-
Structural vibration damping using lightweight, low-wave-speed media
… (LWSM) into a structure yields significant damping if the speed of wave propagation in the medium is low enough for standing waves to arise in it. In this thesis, we characterize wave propagation in low-density granular media and foams for use as structural damping treatments and develop …
-
Alternative design optimization formulations – developing and comparing for a vibration damping example
… solutions can be evaluated and compared. Using a vibration absorber design example, the guidelines are enumerated, explained, and used to compose six alternative optimization formulations of the problem. These alternatives formulations vary in objective functions, decision variables, and some …
-
Vibration damping using low-wave-speed media with applications to precision machines
Vibration and noise are an ever-present problem in the majority of mechanical systems, from consumer products to precision manufacturing systems. But most approaches for vibration suppression are expensive and invasive, so only a small subset of the techniques developed in research labs are widely …
-
Multi-resonant Electromagnetic Shunt in Base Isolation for Vibration Damping and Energy Harvesting
… to effectively mitigate the earthquake induced vibrations of low- or mid-rise buildings, and at the same time to efficiently harvest utility-scale energy by using an optimally configured multi-resonant electromagnetic shunt in base isolation. In this research, two multi-resonant shunt …
-
A study of actuator reconfiguration and related implementation issues in active vibration damping
This thesis reports a study in the area of active vibration damping focused primarily on reconfiguration of control actuators following failure of one or more components. Several related issues concerning practical implementation were considered, and these also were discussed. These subjects were …
-
Output feedback rotational maneuvers and vibration damping of Nasa Scole system by inversion theory
… the question of large rotational maneuver and vibration stabilization of NASA Spacecraft Control Laboratory Experiment System (SCOLE). The mathematical model of SCOLE System includes the dynamical equations for rigid body slew maneuver and three dimensional vibration of the rigid space shuttle, …
-
Interfacial Adhesion Evaulation of Uniaxial fiber-Reinforced-Polymer Composites by Vibration Damping of Cantilever Beam
… beam shear and transverse tensile tests, and the vibration damping test. Among these techniques, the vibration damping technique has the advantage of being nondestructive as well as highly sensitive for evaluating the interfacial region, and it can allow the materials industry to rapidly determine …
-
Investigating Ferroelastic and Piezoelectric Vibration Damping Behavior in Nickel-Barium Titanate and Nickel-PZT Composites
… composites are new materials being explored for vibration damping purposes. The high damping ability of ferroelectric and piezoelectric ceramics such as barium titanate (BaTiO3) and lead zirconate titanate (PZT) is due to the anelastic response of ferroelastic domain walls to applied external …
-
An experimental and theoretical analysis of active vibration damping of a cantilever beam using a distributed actuator
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1986.
-
An approach of using polymer natural fiber composite for vibration and flammability control
… behaviour, mechanical properties, vibration damping properties and flammability properties of kenaf fiber and coir fiber reinforced polypropylene were investigated. Different fractions of composites with 10wt%-40wt% coir fiber (CF) and kenaf fiber (KF) content were prepared by using …
-
Advanced Control Strategies for Mobile Hydraulic Applications
… dynamics, mainly discontinuous motion and vibrations. Over the years, many methods have been developed to limit the extent of those undesired dynamics and improve controllability and safety of operation of the machine. However, in most of the cases, today's methods do not significantly …
-
Optimum Damping of Beam Vibrations Using Piezoceramic Transducers
… the optimal electric tuning parameters for vibration damping. A numerical code based upon Galerkin weighted-residual method is developed and the complete piezo-electro-mechanical system is designed, realized and finally tested by a standard modal testing technique. Comparisons between …
-
Measuring Acoustic Attenuation of Polymer Materials Using Drop Ball Test
<p>Polymers are often used for vibration damping and energy absorption. The effect of a material in reducing the strength of sound waves traveling through it is called acoustic attenuation. In the past, attenuation has mostly been evaluated in the MHz frequency range, using a pulse generator and …
-
A Mechanistic Understanding of the β to α′′ Transformation in Superelastic Ti-24Nb-4Zr-8Sn (wt%)
… alloys have potential for application in vibration damping systems, due to their wide mechanical hysteresis and large recoverable strains, arising from a re- versible martensitic transformation between a parent bcc β phase and an orthorhombic α′′ martensite. Of these alloys, those based on …
-
Fabrication and characterization of Ni-Mn-Ga ferromagnetic shape-memory alloy composites
… this material attractive for energy absorption/vibration damping applications. This thesis describes the preliminary investigation of FSMA/polymer composites for eventual use in vibration damping, and should serve as a stepping stone toward further studies. The research moved through four …
-
Cellulose Nanofoams: 3D Printing and Characterization
… including thermal insulation, shock and vibration damping, as well as tissue engineering.
-
Electromechanical Coupling of Distributed Piezoelectric Transducers for Passive Damping of Structural Vibrations: Comparison of Network Configurations
In this work passive piezoelectric devices for vibration damping are studied. It is developed the basic idea of synthesizing electrical wave guides to obtain an optimal electro-mechanical energy exchange and therefore to dissipate the mechanical vibrational energy in the electric form. Modular …
-
Design and Additive Manufacturing of Carbon-Fiber Reinforced Polymer Microlattice with High Stiffness and High Damping
… limited due to their poor energy dissipation and vibration damping capabilities. This thesis presents a two-phase microlattice design to overcome this problem. To realize this design, a novel tape casting integrated multi-material stereolithography system is developed and mechanical properties of …
-
Effect of base metal oxygen content and oxygen activity on mechanical properties of EN-GJL- GG - 26 Cu-Cr grey cast-iron heavy-duty crank cases
… which include strong heat conductivity, vibration damping capabilities, and superior machinability. One of the key development trends for grey cast-iron applications is the need for increased tensile strength, which will allow higher peak engine pressure, that leads to more efficient …
Page 1 of 2