J. Vib. Acoust.: All Topics http://scitation.aip.org/ J. Vib. Acoust.: All Topics Structural Damping Identification for Mistuned Bladed Disks and Blisks http://link.aip.org/link/doi/10.1115/1.4005009 Darren E. Holland, Bogdan I. Epureanu, and Sergio Filippi<br/> To accurately predict the dynamics of most structures, a representation of damping must be used. This paper focuses on structural damping and the identification of structural damping for complex systems with cyclic symmetry such as bladed disks and integrated (one-piece) bladed disks (blisks) with m ... [J. Vib. Acoust. 134, 024504 (2012)] published Wed Jan 18, 2012. Cylindrical Shell Control With Center- and Corner-Placed Photostrictive Skew-Quad Actuator Systems http://link.aip.org/link/doi/10.1115/1.4005023 J. Jiang, H. H. Yue, Z. Q. Deng, and H. S. Tzou<br/> Light-driven photostrictive actuators can induce control actions for wireless non-contact actuation and control of precision structures and systems. Conventional distributed actuators laminated on shells and plates usually only introduce uniform control forces and moments. Structural actuation and c ... [J. Vib. Acoust. 134, 024503 (2012)] published Wed Jan 18, 2012. Reliable and Evolvable Vibration Suppression by Self-Powered Digital Vibration Control http://link.aip.org/link/doi/10.1115/1.4005027 Shinsuke Takeuchi, Kanjuro Makihara, and Junjiro Onoda<br/> A reliable and evolvable vibration suppression technique using a digital processor powered by energy harvested from a piezoelectric element was developed and investigated. This technique, called a self-powered digital vibration control, benefits from both the sophisticated control logic of the digit ... [J. Vib. Acoust. 134, 024502 (2012)] published Wed Jan 18, 2012. A Comparison of the Effects of Nonlinear Damping on the Free Vibration of a Single-Degree-of-Freedom System http://link.aip.org/link/doi/10.1115/1.4005010 Bin Tang and M. J. Brennan<br/> This article concerns the free vibration of a single-degree-of-freedom (SDOF) system with three types of nonlinear damping. One system considered is where the spring and the damper are connected to the mass so that they are orthogonal, and the vibration is in the direction of the spring. It is shown ... [J. Vib. Acoust. 134, 024501 (2012)] published Fri Jan 13, 2012. Dynamic Modeling and Analysis of Mechanical Snubbing http://link.aip.org/link/doi/10.1115/1.4005012 Sudhir Kaul<br/> This paper presents four alternate models of varying complexity to examine mechanical snubbing in elastomeric isolators. Although the modeling, analysis, and experimentation presented is limited to snubbing of elastomeric isolators, the models are generic and can be adapted to other snubbing mechani ... [J. Vib. Acoust. 134, 021020 (2012)] published Mon Jan 30, 2012. Rapid Heating Induced Vibration of Magnetostrictive Functionally Graded Material Plates http://link.aip.org/link/doi/10.1115/1.4004663 C. C. Hong<br/> The thermal vibration study of magnetostrictive functionally graded material (FGM) plate under rapid heating is computed by using the generalized differential quadrature (GDQ) method. The dynamic equilibrium differential equations with displacements and shear rotations of magnetostrictive FGM plate ... [J. Vib. Acoust. 134, 021019 (2012)] published Thu Jan 26, 2012. Force Feedback Control for Active Stabilization of Synchronous Whirl Orbits in Rotor Systems With Nonlinear Stiffness Elements http://link.aip.org/link/doi/10.1115/1.4005021 M. O. T. Cole, C. Chamroon, and P. Ngamprapasom<br/> Synchronous vibration in rotor systems having bearings, seals, or other elements with nonlinear stiffness characteristics is prone to amplitude jump when operating close to critical speeds as there may be two or more possible whirl motions for a given unbalance condition. This paper describes resear ... [J. Vib. Acoust. 134, 021018 (2012)] published Thu Jan 26, 2012. An Experimental Investigation of State-Variable Modal Decomposition for Modal Analysis http://link.aip.org/link/doi/10.1115/1.4003156 Umar Farooq and Brian F. Feeny<br/> This work presents the experimental evaluation of the state-variable modal decomposition method for a modal parameter estimation of multidegree-of-freedom and continuous vibration systems. Using output response ensembles only, the generalized eigenvalue problem is formed to estimate eigenfrequencies ... [J. Vib. Acoust. 134, 021017 (2012)] published Thu Jan 26, 2012. Active Damping of Nonlinear Vibrations of Functionally Graded Laminated Composite Plates using Vertically/Obliquely Reinforced 1-3 Piezoelectric Composite http://link.aip.org/link/doi/10.1115/1.4004604 Satyajit Panda and M. C. Ray<br/> This paper deals with a study on the active constrained layer damping (ACLD) of geometrically nonlinear vibrations of functionally graded (FG) laminated composite plates. The constraining layer of the ACLD treatment is considered to be made of the vertically/obliquely reinforced 1-3 piezoelectric co ... [J. Vib. Acoust. 134, 021016 (2012)] published Thu Jan 26, 2012. Active Vibration Control of Beams by Combining Precompressed Layer Damping and ACLD Treatment: Performance Comparison of Various Robust Control Techniques http://link.aip.org/link/doi/10.1115/1.4004997 Rajiv Kumar<br/> It is a well known fact that system parameters of the flexible structures keep on changing due to several reasons. Ordinary controllers lose their effectiveness in changed situations and do not guarantee the stability of the closed loop system. However, controllers designed based on robust control t ... [J. Vib. Acoust. 134, 021015 (2012)] published Thu Jan 26, 2012. Phase Space Feature Based on Independent Component Analysis for Machine Health Diagnosis http://link.aip.org/link/doi/10.1115/1.4005006 Qingbo He, Ruxu Du, and Fanrang Kong<br/> This paper proposes a new feature extraction method based on Independent Component Analysis (ICA) and reconstructed phase space. The ICA-based phase space feature unifies the system dynamics embedded in vibration signal and higher-order statistics expressed in phase spectrum and hence, is effective ... [J. Vib. Acoust. 134, 021014 (2012)] published Thu Jan 19, 2012. A Squeeze-Flow Mode Magnetorheological Mount: Design, Modeling, and Experimental Evaluation http://link.aip.org/link/doi/10.1115/1.4005011 T. M. Nguyen, C. Ciocanel, and M. H. Elahinia<br/> This paper presents a dual-mode magnetorheological (MR) fluid mount. Combining the fluid's flow and squeeze modes of operation gives this MR mount a unique possibility for varying dynamic stiffness and damping. Details on the design of the internal structure of the mount and the magnetic circuit are ... [J. Vib. Acoust. 134, 021013 (2012)] published Wed Jan 18, 2012. Efficiency Improvement of an Automatic Ball Balancer http://link.aip.org/link/doi/10.1115/1.4005013 Yukio Ishida, Tomonori Matsuura, and Xiao Long Zhang<br/> An automatic ball balancer is a unique vibration suppression device for rotor systems. Theoretically, two balls in a cylindrical chamber of the rotor are located at the optimal positions on the opposite side to the unbalance and cancel the unbalance automatically in the super-critical speed range. H ... [J. Vib. Acoust. 134, 021012 (2012)] published Wed Jan 18, 2012. Wave Analysis of In-Plane Vibrations of L-Shaped and Portal Planar Frame Structures http://link.aip.org/link/doi/10.1115/1.4005014 C. Mei<br/> This paper concerns in-plane vibration analysis of coupled bending and longitudinal vibrations in L-shaped and portal planar frame structures. An exact analytical solution is obtained using wave vibration approach. The classical Euler-Bernoulli as well as the advanced Timoshenko bending theories are ... [J. Vib. Acoust. 134, 021011 (2012)] published Wed Jan 18, 2012. Optimal Parameters and Characteristics of a Three Degree of Freedom Dynamic Vibration Absorber http://link.aip.org/link/doi/10.1115/1.4004667 Mariano Febbo<br/> The present study is devoted to the determination of the optimal parameters and characteristics of a three degree of freedom dynamic vibration absorber (3 DOF DVA) for the vibration reduction of a plate at a given point. The optimization scheme uses simulated annealing and constrained simulated anne ... [J. Vib. Acoust. 134, 021010 (2012)] published Wed Jan 18, 2012. Vibration Reduction Index of a T-Junction With a Flexible Interlayer http://link.aip.org/link/doi/10.1115/1.4004675 J. Alba, E. Escuder, J. Ramis, R. Del Rey, and E.G. Segovia<br/> This paper describes the procedure followed to evaluate the vibration reduction index for T-junctions with inserted flexible elements and proposes new equations to complement the standard EN 12354-1:2000. The experiment described in this work is based on a 1:3 scale model of a T-junction with a flex ... [J. Vib. Acoust. 134, 021009 (2012)] published Wed Jan 18, 2012. Investigation of Period-Doubling Islands in Milling With Simultaneously Engaged Helical Flutes http://link.aip.org/link/doi/10.1115/1.4005022 Firas A. Khasawneh, Oleg A. Bobrenkov, Brian P. Mann, and Eric A. Butcher<br/> This paper investigates the stability of a milling process with simultaneously engaged flutes using the state-space TFEA and Chebyshev collocation methods. In contrast to prior works, multiple flute engagement due to both the high depth of cut and high step-over distance are considered. A particular ... [J. Vib. Acoust. 134, 021008 (2012)] published Wed Jan 18, 2012. Fully Coupled Finite-Element Modeling of Active Sandwich Panels With Poroelastic Core http://link.aip.org/link/doi/10.1115/1.4005026 Tomasz G. Zielinski, Marie-Annick Galland, and Mohamed N. Ichchou<br/> Active sandwich panels are an example of smart noise attenuators and a realization of hybrid active-passive approach for the problem of broadband noise reduction. The panels are composed of thin elastic faceplates linked by the core of a lightweight absorbent material of high porosity. Moreover, the ... [J. Vib. Acoust. 134, 021007 (2012)] published Wed Jan 18, 2012. Vibration Analysis of a Self-Excited Vibration in a Rotor System Caused by a Ball Balancer http://link.aip.org/link/doi/10.1115/1.4005141 Tsuyoshi Inoue, Yukiko Ishida, and Hideaki Niimi<br/> The ball balancer has been used as a vibration suppression device in rotor systems. It has a superior characteristic that the vibration amplitude is reduced to zero theoretically at a rotational speed range higher than the critical speed. However, the ball balancer causes a self-excited vibration ne ... [J. Vib. Acoust. 134, 021006 (2012)] published Wed Jan 18, 2012. Genetic Algorithm Optimization on a Venting System With Three-Chamber Hybrid Mufflers Within a Constrained Back Pressure and Space http://link.aip.org/link/doi/10.1115/1.4005220 Min-Chie Chiu<br/> Recently, research on new techniques for dissipative mufflers in dealing with the higher frequencies has been addressed. However, the shape optimization of hybrid mufflers in reducing broadband noise within a constrained space as well as a pressure-drop limit which are both concerned with the necess ... [J. Vib. Acoust. 134, 021005 (2012)] published Wed Jan 18, 2012. Two Algorithms for Mass Normalizing Mode Shapes From Impact Excited Continuous-Scan Laser Doppler Vibrometry http://link.aip.org/link/doi/10.1115/1.4005020 Shifei Yang, Michael W. Sracic, and Matthew S. Allen<br/> Continuous-scan laser Doppler vibrometry (CSLDV), a concept where a vibrometer measures the motion of a structure as the laser measurement point sweeps over the structure, has proven to be an effective method for rapidly obtaining mode shape measurements with very high spatial detail using a complet ... [J. Vib. Acoust. 134, 021004 (2012)] published Fri Jan 13, 2012. Extreme-Value-Based Statistical Bounding of Low, Mid, and High Frequency Responses of a Forced Plate With Random Boundary Conditions http://link.aip.org/link/doi/10.1115/1.4005019 A. Secgin, J. F. Dunne, and L. Zoghaib<br/> The problem of statistically bounding the response of an engineering structure with random boundary conditions is addressed across the entire frequency range: from the low, through the mid, to the high frequency region. Extreme-value-based bounding of both the FRF and the energy density response is ... [J. Vib. Acoust. 134, 021003 (2012)] published Fri Jan 13, 2012. Specified Motion of Piezoelectrically Actuated Structures http://link.aip.org/link/doi/10.1115/1.4005018 T. M. Seigler and A. H. Ghasemi<br/> The problem considered is that of solving for the control input that generates partly specified motion of a deformable structure with distributed piezoelectric actuation. The motion constraint, called the program constraint, is specified as a desired relation on the motion of selected material point ... [J. Vib. Acoust. 134, 021002 (2012)] published Fri Jan 13, 2012. Passive and Switched Stiffness Vibration Controllers Using Fluidic Flexible Matrix Composites http://link.aip.org/link/doi/10.1115/1.4002957 Amir Lotfi-Gaskarimahalle, Lloyd H. Scarborough, Christopher D. Rahn, and Edward C. Smith<br/> This paper investigates passive and semi-active vibration control using fluidic flexible matrix composites (FMC). FMC tubes filled with fluid and connected to an accumulator through a fixed orifice can provide damping forces in response to axial strain. If the orifice is actively controlled, the sti ... [J. Vib. Acoust. 134, 021001 (2012)] published Fri Jan 13, 2012.