Article
Engineering, Mechanical
Xiaohua Liu, Ning Chen, Junrui Jiao, Jian Liu
Summary: This paper presents a computationally designed pneumatic soft phononic crystal for tunable band gap. By mechanically generating deformation through air pressure, the band gap in the crystal can be opened or closed, and its width can be adjusted. The study shows that pneumatic manipulation is a low-cost, fast, and easily integrated means compared to traditional mechanical deformation methods.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2023)
Article
Physics, Multidisciplinary
Wei Ding, Tianning Chen, Chen Chen, Dimitrios Chronopoulos, Badreddine Assouar, Yongzheng Wen, Jian Zhu
Summary: This study introduces an analogy with Thomson scattering in electromagnetic waves to characterize the bandgap phenomena in chiral phononic crystals (PnCs) with translation-rotation coupling. The coupling motion in chiral unit cells is found to be similar to the result of Thomson scattering, resulting in the formation of bandgaps.
NEW JOURNAL OF PHYSICS
(2023)
Article
Engineering, Mechanical
Pawel Kudela, Abdalraheem Ijjeh, Maciej Radzienski, Marco Miniaci, Nicola Pugno, Wieslaw Ostachowicz
Summary: In this work, a novel approach for the topology optimization of phononic crystals using deep learning is proposed. The trained deep learning model is able to predict dispersion diagrams quickly, making it suitable for efficient optimization. The use of non-uniform rational basis spline curves and a genetic algorithm further enhances the optimization process. The method has been validated in the design of phononic crystals with cavities and offers potential for computer-assisted design of periodic structures.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2023)
Article
Acoustics
Xiao-Shuang Li, Xiao-Lei Tang, Xiao-Xing Su, Chuanzeng Zhang, Yue-Sheng Wang
Summary: In this study, three-dimensional phononic crystal-based coupled resonator waveguides (PnCCRWs) are proposed for guiding acoustic waves along complex routes. The interaction between the PnC point defects is described by the tight-binding model, enabling the propagation of acoustic wave energy along designated paths.
JOURNAL OF SOUND AND VIBRATION
(2022)
Article
Physics, Condensed Matter
Yi Wang, Ying Liu, Dong Zhao, Shuai Yang
Summary: This paper investigates the wave dispersion in a light-sensitive liquid crystal elastomer porous phononic crystal and proposes an opto-mechanical indirect-coupling strategy. The results show that the properties of absolute band gaps are affected by light intensity, director orientation, and porosity. These findings promise prospective applications in the intelligent tuning of band structure in pononnic crystals.
PHYSICA B-CONDENSED MATTER
(2022)
Review
Physics, Multidisciplinary
Geon Lee, Dongwoo Lee, Jeonghoon Park, Yeongtae Jang, Miso Kim, Junsuk Rho
Summary: Mechanical metamaterials and phononic crystals can localize, focus, and guide elastic or acoustic waves in various ways. These man-made structures allow for more efficient collection of energy and have a wide range of potential applications in renewable energy transformation.
COMMUNICATIONS PHYSICS
(2022)
Article
Engineering, Electrical & Electronic
Shrouk E. Zaki, Ahmed Mehaney, Arafa H. Aly
Summary: In this work, a one-dimensional defective phononic crystal was introduced as a novel heavy metal sensor for detecting NiCl2 concentrations in water. Different sensitivity, quality factor, and resonance peaks were observed based on the concentration of NiCl2 in the sensor.
OPTICAL AND QUANTUM ELECTRONICS
(2022)
Article
Crystallography
Zexin Zhang, Denghui Qian, Peng Zou
Summary: A new type of phononic crystal beam structure is constructed to solve the vibration and noise control problems in engineering fields. The vibration modes of the band structure, the critical point of the band gap, and the vibration transmission of the finite structure are estimated using the finite element method and the Bloch theorem, and then the band gap characteristics of the structure are comprehensively studied. Reasonable parameter design can achieve vibration and noise control in a certain frequency range. The advantages of the double-layer beam in vibration reduction and noise reduction are shown by comparing it with the single-layer beam with the same parameters. The findings of this study offer a fresh concept for ship engineering disciplines including vibration and noise reduction technology.
Article
Materials Science, Multidisciplinary
Zuguang Bian, Xiaoliang Zhou
Summary: This paper introduces a discrete tuning method by transforming the phases of components, allowing for easy control of band gaps in phononic crystals in finite states. Simulations using the finite element method show significant changes in band gaps when phase transformations of components occur. This work lays the theoretical foundation for manufacturing a phononic crystal acting as an acoustic switch.
MECHANICS OF ADVANCED MATERIALS AND STRUCTURES
(2021)
Article
Chemistry, Multidisciplinary
Xinzhu Li, Ignas Lekavicius, Hailin Wang
Summary: In this study, we report the design, fabrication, and characterization of diamond cantilevers attached to a phononic square lattice. We show that the robust protection provided by phononic band gaps significantly increases the mechanical Q-factors, with Q-factors exceeding 106 at frequencies as high as 100 MHz. Temperature-dependent studies reveal that the Q-factors obtained at low temperatures are still limited by materials loss. These high-Q diamond nanomechanical resonators offer a promising hybrid quantum system for spin-mechanics studies.
Article
Materials Science, Multidisciplinary
Lijian Lei, Linchang Miao, Haizhong Zheng, Pengteng Wu, Minghui Lu
Summary: This paper introduces the outward hierarchical locally resonant phononic crystal (OHLRPC) structure and investigates its band gap characteristics and mechanism through band structure and modal analysis. A band gap determination formula is proposed. Parameter analysis shows that the band gap location and width can be optimized to achieve low-frequency and broadband simultaneously.
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
(2022)
Article
Nanoscience & Nanotechnology
Soo-Ho Jo, Heonjun Yoon, Yong Chang Shin, Wonjae Choi, Byeng D. Youn, Miso Kim
Summary: This study proposes an L-shaped arrangement of triple defects in a phononic crystal for broadband piezoelectric energy harvesting. The design effectively confines and harvests elastic-wave energy over a wide range of frequencies, overcoming the limitations of single and double defect designs.
Article
Physics, Applied
Etienne Coffy, Sebastien Euphrasie, Pascal Vairac, Abdelkrim Khelif
Summary: The experimental high spatial confinement of elastic energy in a silicon phononic cantilever is achieved by using a three-row phononic crystal (PnC) strip, increasing the quality factor of a higher-order flexural resonance by a factor of 27; Numerical simulations show that the PnC reduces anchor loss and confines elastic energy inside the cantilever; Both the PnC and the cantilever are fabricated using standard clean room techniques on a silicon on insulator substrate. Optical measurements of the out-of-plane displacements are performed with a laser scanning interferometer in a frequency range around 2 MHz.
APPLIED PHYSICS LETTERS
(2021)
Article
Materials Science, Multidisciplinary
Junyu Li, Xiaowen Wu, Chenlin Wang, Qibai Huang
Summary: This paper proposes a four-vibrator acoustic metamaterial structure with phononic crystals, aiming to broaden the sound insulation performance at medium and high frequencies while retaining the advantages of sound insulation at low frequencies. The sound insulation performance and characteristics of the structure are analyzed using a semi-analytical method and an equivalent medium method, and its performance in a cylindrical state is verified through finite element simulation.
MATERIALS TODAY COMMUNICATIONS
(2023)
Article
Materials Science, Multidisciplinary
Kenny L. S. Yip, Sajeev John
Summary: Locally resonant acoustic materials are proposed for sound control by using resonant oscillators consisting of heavy mass within a light shell embedded in foam. The effective, frequency-dependent mass densities of these oscillators are derived and used to evaluate the acoustic band structure in two dimensions. The accuracy of the results is validated by comparing with exact solutions obtained through numerical simulations.
Article
Instruments & Instrumentation
J. Callanan, C. L. Willey, V. W. Chen, J. Liu, M. Nouh, A. T. Juhl
Summary: A new class of electromechanically coupled metamaterial is introduced, which can realize vibration control through magnetic field interactions and exhibit a highly tunable vibration band gap with adjustable resonant circuit parameters.
SMART MATERIALS AND STRUCTURES
(2022)
Article
Engineering, Multidisciplinary
Abdulaziz Aladwani, Mostafa Nouh, Mahmoud I. Hussein
Summary: This paper generalizes the Bloch mode synthesis (BMS) approach using state-space transformation to extend its applicability to generally damped periodic materials. The study examines mode-selection schemes for non-classically damped periodic models and demonstrates the trade-offs between accuracy and efficiency.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2022)
Article
Acoustics
A. Stein, M. Nouh, T. Singh
Summary: This paper investigates the behavior of acoustic metamaterials with multiple resonating elements, showing how different configurations of resonators can be used to expand the frequency range of band gaps, enabling a wider range of wave propagation profiles. The study develops analytical expressions for multi-resonator metamaterials, revealing the mechanisms behind band gap widening and dispersion transitions in parallel resonator metamaterials, as well as the potential for collapsing solutions of acoustic and optical bands in metamaterials with dual-periodic super cells.
JOURNAL OF SOUND AND VIBRATION
(2022)
Article
Automation & Control Systems
Y. Kim, T. Singh
Summary: This paper focuses on the energy-time optimal control problem of wheeled mobile robots undergoing point-to-point transitions in an obstacles free space. Two models are used to derive the necessary conditions for optimality, and Jacobi elliptic functions are used to parameterize the solutions. The analysis reveals that the optimal control is constrained on the intersection of cylinders.
JOURNAL OF THE FRANKLIN INSTITUTE-ENGINEERING AND APPLIED MATHEMATICS
(2022)
Article
Chemistry, Multidisciplinary
Kyung Hoon Lee, Hasan Al Ba'ba'a, Kunhao Yu, Ketian Li, Yanchu Zhang, Haixu Du, Sami F. Masri, Qiming Wang
Summary: This study presents a magnetoactive acoustic topological transistor that can switch on and off topological states and reconfigure topological edges using external magnetic fields. By tuning the air-cavity volumes within acoustic chambers and utilizing a non-topological band gap, the switching of topological transport and the construction of topological field-effect waveguides and wave regulators are demonstrated.
Article
Multidisciplinary Sciences
Hasan B. B. Al Ba'ba'a, Carson L. Willey, Vincent W. W. Chen, Abigail T. Juhl, Mostafa Nouh
Summary: This paper investigates the vibrational spectrum of finite phononic crystals in the form of one-dimensional rods and explains the factors that contribute to the origination of truncation resonances. By identifying a unit cell symmetry parameter, a family of finite phononic rods is defined. A transfer matrix method is utilized to derive closed-form expressions of the characteristic equations governing the natural frequencies and decipher the truncation resonances. This study establishes concrete connections between the localized vibrations, boundary conditions, and the configuration of the truncated chain, providing tools for predicting, tuning, and selectively designing truncation resonances.
ADVANCED THEORY AND SIMULATIONS
(2023)
Article
Automation & Control Systems
Oladapo Ogunbodede, Tarunraj Singh
Summary: The paper focuses on designing open-loop control profiles for linear differentially flat systems with uncertain and probabilistically represented model parameters. Polynomial chaos is used to derive a surrogate model for time-invariant parameter uncertainties, allowing easy evaluation of mean and variance of the uncertain states. A chance constrained optimization problem is proposed to minimize terminal error of stochastic states while ensuring a prescribed risk of not satisfying terminal state bounds. The technique is illustrated on two examples and parametric studies indicate the impact of varying polynomial chaos expansion order and degree of parameterized control profiles.
INTERNATIONAL JOURNAL OF CONTROL
(2023)
Article
Engineering, Mechanical
Adrian Stein, Tarunraj Singh
Summary: This paper develops minimum time control profiles for point-to-point motion of a gantry crane system in the presence of uncertainties in modal parameters. An optimal control problem is posed to determine the bang-off-bang control profile to achieve vibration-free transitions. The influence of the final displacement on the optimal control profile is studied. The experimental results illustrate the tradeoff between maneuver time and reduction of residual vibrations.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2023)
Article
Instruments & Instrumentation
R. Adlakha, M. Nouh
Summary: In this paper, a class of non-Hermitian phased arrays is proposed to achieve selective directional suppression of harmonics by adjusting the amplitude modulation using gain, loss, and coupling between components. An experimental prototype is constructed to demonstrate the capability of selective directional suppression. The theory and experimental realization of non-Hermitian phased arrays provide new opportunities for precise elastoacoustic wave manipulation in various engineering applications.
SMART MATERIALS AND STRUCTURES
(2023)
Article
Education, Scientific Disciplines
Adrian Stein, Tarik Parcic, Tarunraj Singh
Summary: The paper presents the design and fabrication of an active pendulum with adjustable length to demonstrate two concepts: damping of pendulum oscillations resembling a crane's sway and amplification of oscillations resembling a playground swing. The paper describes the steps before experimental validation, including modeling, system identification, signal processing, and controller implementation. Numerical simulations are used to prototype the controller and compare simulation results with experimental results. The experiments show a close match between simulation and experimental results. Design details and controller implementation code are publicly available for replication.
INTERNATIONAL JOURNAL OF MECHANICAL ENGINEERING EDUCATION
(2023)
Article
Acoustics
Hasan B. Al Ba'ba'a
Summary: The definition of Brillouin zone (BZ) in a class of non-reciprocal Willis monatomic lattices (WMLs) is quantitatively analyzed. It is found that BZ boundaries only shift in response to non-reciprocity in one-dimensional WMLs, resulting in a constant BZ width. The dispersion diagrams exhibit unequal wavenumber ranges for forward and backward going waves. A similar phenomenon is observed in square WMLs, where shifted and irregularly shaped BZs emerge while maintaining constant areas regardless of non-reciprocity strength.
JASA EXPRESS LETTERS
(2023)
Article
Materials Science, Multidisciplinary
Mohammadreza Moghaddaszadeh, Andrew Ragonese, Yong Hu, Zipeng Guo, Amjad Aref, Chi Zhou, Shenqiang Ren, Mostafa Nouh
Summary: This study presents an experimental framework for controlling local resonance bandgap in a magnetically programmable metamaterial based on magnetorheological elastomers. The alignment of ferromagnetic particles under an external magnetic field enhances the sensitivity of the metamaterial's elastic modulus, allowing for control of the dispersive dynamics and shifting of the resonance-based bandgap. Numerical simulations also project the performance of the magnetically-tunable metamaterial at higher magnetic fields and levels of material anisotropy.
COMMUNICATIONS MATERIALS
(2023)
Article
Acoustics
Hasan B. Al Ba'ba'a, Kyung Hoon Lee, Qiming Wang
Summary: This article demonstrates the potential of using electroacoustic analogies to design topological acoustic lattices and compares it with the full three-dimensional model. The established analytical framework is of great importance for designing acoustic topological insulators with minimal computational cost.
JOURNAL OF VIBRATION AND ACOUSTICS-TRANSACTIONS OF THE ASME
(2023)
