Elastic metamaterials incorporating locally resonating unit cells can create bandgap regions with lower vibration transmissibility at longer wavelengths than the lattice size and offer a promising solution for vibration isolation and attenuation. However, when resonators are applied to a finite host structure, not only the bandgap but also addition...
A non-linear Euler-Lagrange (EL) controller is proposed for underactuated mechanical Euler-Lagrange systems. The rationale is that mimicking the process structure in the controller will lead to improved performance. The tuning of the controller can be rather intuitive as it can be seen as an auxiliary mechanical system that is connected to the proc...
Varying-length cable systems are widely applied in a vast class of engineering problems which arise in industrial, civil, aerospatial, mechanical, and automotive applications. Due to external excitations, large oscillations can occur when cables are lifted up or down. This phenomenon is caused by resonance. In general, resonance is harmful, and can...
The present paper is aimed to propose a multi-parameter feedback control method combined with couple stress elasticity to model piezoelectric micro plate coupled systems. The proposed methodology can be used to design controllers for tuning vibration and wave propagation properties of micro scale plates based on coupled piezoelectric sensors and ac...
TCC(graduação) - Universidade Federal de Santa Catarina. Centro Tecnológico. Engenharia de Controle e Automação. / A indústria da aviação definiu objetivos econômicos e ambientais ambiciosos com o propósito de reduzir emissões de CO2 e aumentar a eficiência energética. O design de blades (lâminas) combinadas em discos, conhecidos como blisks (blade...
Le contrôle des vibrations des structures minces sous une contrainte d'allègement constitue un enjeu important en ingénierie mécanique, notamment aéronautique et spatiale. L’insertion de Trous Noirs Acoustiques (TNA), ou pièges à ondes de flexion, basés sur une hétérogénéité locale de la raideur et de l’amortissement constitue une technique innovan...
Published in ISA transactions
In this research, a model-free control strategy for vibration suppression of base-isolated structures, which are excited by an earthquake, is investigated. For this purpose, the semi-active base isolated system including a magnetorheological (MR) damper is utilized. In this way, the displacement of the base isolator is measured by a linear variable...
Published in Environmental science and pollution research international
The freight train-induced vibrations and noise generate increasing environmental problems owing to its heavier axle loads and longer pass-by duration. To develop useful mitigation measures, the vibration characteristic induced by this type of rail transportation needs to be better learned. In the present work, firstly, the in situ measurements were...
We treat a chain of oscillators with linear stiffness and internal and external cubic non-linearities. The method of harmonic balance is used to determine the non-linear modes of the Hamiltonian system. For each equilibrium point, a stability analysis is performed by means of the associated monodromy matrix. The numerical results shows that branch ...
peer reviewed / Acoustic Black Hole (ABH) phenomenon features unique wave retarding and energy focusing of flexural waves inside thin-walled structures whose thickness follows a power-law variation. Existing studies, mostly focusing on linear aspects, show the deficiency of the linear ABH structures in coping with low-frequency problems, typically ...
