Relevant bibliographies by topics / Off-axis stiffness

Contents

  1. Journal articles
  2. Dissertations / Theses
  3. Book chapters
  4. Conference papers

Academic literature on the topic 'Off-axis stiffness'

Author: Grafiati
Published: 4 June 2021
Last updated: 1 February 2022

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Journal articles on the topic "Off-axis stiffness"

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Heslehurst, Rikard B. "Off-axis transformation of the composite laminate stiffness properties." Composite Structures 35, no. 4 (August 1996): 369–74. http://dx.doi.org/10.1016/s0263-8223(96)00042-6.

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Garner, Amy, Moneeb Genedy, Usama Kandil, and Mahmoud Reda Taha. "Controlling off-axis stiffness and stress-relaxation of carbon fiber-reinforced polymer using alumina nanoparticles." Journal of Composite Materials 52, no. 18 (December 21, 2017): 2483–91. http://dx.doi.org/10.1177/0021998317748466.

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This investigation experimentally examines the effect of incorporating alumina nanoparticles on the off-axis stiffness and stress-relaxation of carbon fiber-reinforced polymer composites. Four epoxy–alumina nanoparticle nanocomposites incorporating 0.0, 1.0, 2.0, and 3.0 wt% alumina nanoparticles of the total weight of epoxy are examined. Off-axis tension stiffness and stress-relaxation tests were performed on carbon fiber-reinforced polymer coupons fabricated with alumina nanoparticles–epoxy nanocomposites. Dynamic mechanical analysis testing of neat epoxy and epoxy nanocomposites incorporating alumina nanoparticles was used to identify the stiffness and relaxation behavior of the alumina nanoparticles–epoxy nanocomposite matrix. Fourier transform infrared spectroscopy was used to observe chemical changes when alumina nanoparticles are mixed with epoxy. It is shown that using alumina nanoparticles at a concentration close to 2.0 wt%, can reduce the off-axis stiffness by ∼30% and increase the off-axis stress-relaxation of carbon fiber-reinforced polymer by ∼10%.
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Montesano, John, Zouheir Fawaz, Kamran Behdinan, and Cheung Poon. "Fatigue Damage in On-Axis and Off-Axis Woven-Fiber/Resin Composite." Key Engineering Materials 488-489 (September 2011): 230–33. http://dx.doi.org/10.4028/www.scientific.net/kem.488-489.230.

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In this study the tensile static and fatigue behaviour of a woven-fabric laminate is investigated in both the on-axis and off-axis material directions. Emphasis is placed on the development of damage and its influence on the stress-strain behaviour of the laminate. The test results illustrate that there is a high degree of anisotropic behaviour due to anisotropic damage development, which is evident by the variation of the material behaviour between the on-axis and off-axis test specimens. The fatigue tests also suggest that the on-axis specimens exhibit noticeable stiffness degradation, while the off-axis specimens do not. The qualitative results provide significant insight into the type of damage mechanism responsible for the observed behaviour.
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Naves, M., R. G. K. M. Aarts, and D. M. Brouwer. "Large stroke high off-axis stiffness three degree of freedom spherical flexure joint." Precision Engineering 56 (March 2019): 422–31. http://dx.doi.org/10.1016/j.precisioneng.2019.01.011.

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Kashtalyan, Maria, and Costas Soutis. "Stiffness and fracture analysis of laminated composites with off-axis ply matrix cracking." Composites Part A: Applied Science and Manufacturing 38, no. 4 (April 2007): 1262–69. http://dx.doi.org/10.1016/j.compositesa.2006.07.001.

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Trease, Brian P., Yong-Mo Moon, and Sridhar Kota. "Design of Large-Displacement Compliant Joints." Journal of Mechanical Design 127, no. 4 (November 7, 2004): 788–98. http://dx.doi.org/10.1115/1.1900149.

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This paper investigates the drawbacks of typical flexure connectors and presents several new designs for highly effective, kinematically well-behaved compliant joints. A revolute and a translational compliant joint are proposed, both of which offer great improvements over existing flexures in the qualities of (1) a large range of motion, (2) minimal “axis drift,” (3) increased off-axis stiffness, and (4) a reduced stress-concentrations. Analytic stiffness equations are developed for each joint and parametric computer models are used to verify their superior stiffness properties. A catalog of design charts based on the parametric models is also presented, allowing for rapid sizing of the joints for custom performance. A joint range of motion has been calculated with finite element analysis, including stress concentration effects.
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Katerelos, D. G., L. N. McCartney, and C. Galiotis. "Effect of Off – Axis Matrix Cracking on Stiffness of Symmetric Angle-Ply Composite Laminates." International Journal of Fracture 139, no. 3-4 (June 2006): 529–36. http://dx.doi.org/10.1007/s10704-006-0100-9.

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Barret, C., and S. Baste. "Effective Elastic Stiffnesses of an Anisotropic Medium Permeated by Tilted Cracks." Journal of Applied Mechanics 66, no. 3 (September 1, 1999): 680–86. http://dx.doi.org/10.1115/1.2791562.

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This paper is concerned with the relationship between the effective stiffness tensor and the intensity of damage in individual modes for an anisotropic material with tilted cracks. The predictions are compared favorably with the experimentally measured load-induced changes of the 13 stiffnesses of a two-dimensional C/C-SiC ceramic matrix composite subjected to an off-axis solicitation. By taking into account the thickness of the cracks, it is possible to understand the change of the elastic anisotropy of the material and of its inelastic strain.
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Zhou, Qing Kun, Zhi Yong Zhang, Da Peng Fan, and Hua Jie Hong. "Transverse Stiffness and Guiding Characteristics Analysis of Compliant Linear Guided Mechanism." Applied Mechanics and Materials 34-35 (October 2010): 1941–45. http://dx.doi.org/10.4028/www.scientific.net/amm.34-35.1941.

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This paper presents a novel compliant linear guided mechanism (CLGM) to replace traditional spring and translation joint to transfer motion and force with its advanced guiding characteristics. In view of the incompatible relationship between axial stiffness and transverse stiffness of CLGM, eight kinds of CLGMs were developed by using building block approach based on fixed-guided flexure beam. The finite element analysis (FEA) models of eight CLGMs were built to complete numerical analysis on the force-displacement in axis and off-axis direction with same geometric sizes. The FEA results show that the structure configuration of Type 2-Type 8 can achieve a larger axial travel, Type 2 and Type4 have the advanced guiding characteristic with higher ratio of axial/transverse stiffness. Analysis indicates that the building block approach is an efficient method to complete the conceptual synthesis of compliant mechanism and FEA is effective on the structure optimization for the required compliance and stiffness in axial and transverse direction.
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Wang, Y. H., Zheng Dao Wang, and X. X. Zhao. "Prediction of the Fatigue Life Based on Stiffness Degradation Concept." Advanced Materials Research 33-37 (March 2008): 199–204. http://dx.doi.org/10.4028/www.scientific.net/amr.33-37.199.

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In order to predict the fatigue life of matrix-dominated polymer composites, a new model based on stiffness degradation concept was proposed. The effect of off-axis was considered by defining a non-dimensional modified stress level, and the expression of fatigue stress limit could be provided in the new model. Based on the fatigue tension-tension experiment of PI/SiO2 hybrid thin films under different stress levels, the simulated results was confirmed to be well agreeable with the experimental data.
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Dissertations / Theses on the topic "Off-axis stiffness"

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Smith, David G. "Off-axis stiffness and piezoresistive sensing in large-displacement linear-motion microelectromechanical systems /." Diss., CLICK HERE for online access, 2009. http://contentdm.lib.byu.edu/ETD/image/etd3141.pdf.

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Smith, David G. "Off-axis Stiffness and Piezroresistive Sensing in Large-displacement Linear-motion Microelectromechanical Systems." BYU ScholarsArchive, 2009. https://scholarsarchive.byu.edu/etd/1900.

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Proper positioning of Microelectromechanical Systems (MEMS) components influences the functionality of the device, especially in devices where the motion is in the range of hundreds of micrometers. There are two main obstacles to positioning: off-axis displacement, and position determination. This work studies four large-displacement devices, their axial and transverse stiffness, and piezoresistive response. Methods for improving the device characteristics are described. The folded-beam suspension, small X-Bob, large X-Bob and double X-Bob were characterized using non-dimensional metrics that measure the displacement with regard to the size of the device, and transverse stiffness with regard to axial stiffness. The stiffness in each direction was determined using microprobes to induce displacement, and microfabricated force gauges to determine the applied force. The large X-Bob was optimized, increasing the transverse stiffness metric by 67%. Four-point resistance testing and microprobes were used to determine the piezoresistive response of the devices. The piezoresistive response of the X-Bob was maximized using an optimization routine. The resulting piezoresistive response was over seven times larger than that of the initial design. Piezoresistive encoders for ratcheting actuation of large-displacement MEMS are introduced. Four encoders were studied and were found to provide information on the performance of the ratcheting actuation system at frequencies up to 920 Hz. The PMT encoder produced unique signals corresponding to distinct ideal and non-ideal operation of the ratchet wheel actuation system. Encoders may be useful for future applications which require position determination.
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Mackay, Allen B. "Large-Displacement Linear-Motion Compliant Mechanisms." BYU ScholarsArchive, 2007. https://scholarsarchive.byu.edu/etd/901.

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Linear-motion compliant mechanisms have generally been developed for small displacement applications. The objective of the thesis is to provide a basis for improved large-displacement linear-motion compliant mechanisms (LLCMs). One of the challenges in developing large-displacement compliant mechanisms is the apparent performance tradeoff between displacement and off-axis stiffness. In order to facilitate the evaluation, comparison, and optimization of the performance of LLCMs, this work formulates and presents a set of metrics that evaluates displacement and off-axis stiffness. The metrics are non-dimensionalized and consist of the relevant characteristics that describe mechanism displacement, off-axis stiffness, actuation force, and size. Displacement is normalized by the footprint of the device. Transverse stiffness is normalized by a new performance characteristic called virtual axial stiffness. Torsional stiffness is normalized by a performance characteristic called the characteristic torque. Because large-displacement compliant mechanisms are often characterized by non-constant axial and off-axis stiffnesses, these normalized stiffness metrics are formulated to account for the variation of both axial and off-axis stiffness over the range of displacement. In pursuit of mechanisms with higher performance, this work also investigates the development of a new compliant mechanism element. It presents a pseudo-rigid-body model (PRBM) for rolling-contact compliant beams (RCC beams), a compliant element used in the RCC suspension. The loading conditions and boundary conditions for RCC beams can be simplified to an equivalent cantilever beam that has the same force-deflection characteristics as the RCC beam. Building on the PRBM for cantilever beams, this paper defines a model for the force-deflection relationship for RCC beams. Included in the definition of the RCC PRBM are the pseudo-rigid-body model parameters that determine the shape of the beam, the length of the corresponding pseudo-rigid-body links and the stiffness of the equivalent torsional spring. The behavior of the RCC beam is parameterized in terms of a single parameter defined as clearance, or the distance between the contact surfaces. The RCC beams exhibit a unique force-displacement curve where the force is inversely proportional to the clearance squared. The RCC suspension is modeled using the newly defined PRBM. The suspension exhibits unique performance, generating no resistance to axial motion while providing significant off-axis stiffness. The mechanism has a large range of travel and operates with frictionless motion due to the rolling-contact beams. In addition to functioning as a stand-alone linear-motion mechanism, the RCC suspension can be configured with other linear mechanisms in superposition to improve the off-axis stiffness of other mechanisms without affecting their axial resistance.
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Battley, Mark Andrew. "Off-axis stiffness characterisation of fibre reinforced plastics." 1993. http://hdl.handle.net/2292/2513.

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A new theoretical characterisation is developed for the off-axis stiffness of FRP materials. The theoretical model treats an off-axis unidirectional ply as an inhomogeneous material, and considers the effect of rigid body rotations of the fibres within the matrix material. Linear analytical, and nonlinear finite element solutions are developed for the model. The differences between the new model and the traditional homogenous orthotropic characterisation are functions of both the strain level, and the relative modulus ratio (Ef/Em) of the constituent materials. For relative constituent moduli typical of most common FRP materials, there are significant differences between the new Rigid Body Motion (RBM) model and homogenous orthotropic characterisations at strains greater than 1%. In a 30° case with Ef/Em = 100 and a strain level of 2%, the RBM theory predicts a longitudinal modulus 11% higher than the linear orthotropic theory. At small strain levels the RBM theory reduces to the homogenous orthotropic approximation. A simple and reliable methodology is developed and verified for the experimental characterisation of off-axis tensile FRP specimens. The method applies a tensile load to a thin walled tubular specimen through a high strength, small diameter length of steel wire. The low torsional stiffness of the wire allows one end of the tube to rotate, thus preventing any torsional constraint. Analytical and experimental verifications both indicate that the required tensile load can be applied to tubular specimens without significant torsional constraint. The wire based testing method is used to measure the off-axis stiffness properties of carbon/epoxy tubular specimens at a range of fibre orientations.
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Book chapters on the topic "Off-axis stiffness"

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Lee-Sullivan, P., and A. Poursartip. "Stiffness Change and R-Curve Behaviour Due to Matrix Cracking in Off-Axis Plies of Glass/Epoxy Laminates." In Fracture of Engineering Materials and Structures, 159–64. Dordrecht: Springer Netherlands, 1991. http://dx.doi.org/10.1007/978-94-011-3650-1_21.

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Tsai, Stephen W., and H. Thomas Hahn. "off-axis stiffness of unidirectional composites." In Introduction to Composite Materials, 65–114. Routledge, 2018. http://dx.doi.org/10.1201/9780203750148-3.

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Chimenti, Dale, Stanislav Rokhlin, and Peter Nagy. "Bulk Ultrasonic Techniques for Evaluation of Elastic Properties." In Physical Ultrasonics of Composites. Oxford University Press, 2011. http://dx.doi.org/10.1093/oso/9780195079609.003.0007.

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Currently, the design of most composite components is based on stiffness, and therefore methods for static measurement of stiffness are in wide use. The disadvantages of these methods lie in their destructive nature (the samples must be cut from parts of different orientations), in the difficulty of measuring shear properties, and in the need for extra care when measuring Young’s modulus in off-axis directions. Ultrasonic methods are more accurate and have higher spatial resolution than static measurements. As we showed in Chapter 2, by measuring ultrasonic velocities in several predefined directions, all elastic constants can be determined. The generic method described there is also destructive, however, requiring cutting numerous samples with appropriate fiber orientation. Specialized nondestructive methods for determining the elastic moduli of composite materials are more powerful and they can be applied to composite coupons before, during, and after strength or fatigue testing. It is important to have a fast and inexpensive technique to estimate input parameters for composite design. It is even more important to have a technique to evaluate composites during service to verify that the manufactured elastic stiffnesses match those assumed in the design. Several methods that utilize bulk ultrasonic waves for measurement of composite elastic constants are considered in this chapter. By bulk wave methods, we mean quasilongitudinal and quasitransverse ultrasonic wave velocity measurement methods that are applicable when the sample thickness h is larger than both the ultrasonic pulse space length τV and the wavelength λ (τ is the ultrasonic pulse length in time, and V is the wave speed). Other methods, which are applicable in the range h < τV and which account for wave interference with the boundaries of the specimen, will be considered in the following chapters. The most promising way to evaluate composite elastic properties nondestructively is to measure ultrasonic velocities in different directions in the composite material and reconstruct the elastic constants from these values using some kind of an inversion technique. One possible method has been suggested by Markham in the 1970s, who used ultrasonic waves obliquely incident from water onto a composite plate to measure ultrasonic velocities in various directions and evaluated the results to determine elastic constants.
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Conference papers on the topic "Off-axis stiffness"

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Smith, David G., Gerrit T. Larsen, and Larry L. Howell. "Design Optimization of a Linear-Motion Large-Displacement Micro Mechanism for High Off-Axis Stiffness." In ASME 2009 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2009. http://dx.doi.org/10.1115/detc2009-87301.

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This paper presents research on the large-displacement linear-motion planar compliant mechanism (X-Bob) specific to MEMS applications. The X-Bob’s potential for high off-axis stiffness makes it a strong candidate for precision MEMs applications. Understanding the characteristics and performance of the X-Bob can lead to the ability to modify it to fit specific applications. In this work, an X-Bob design is optimized for increased off-axis stiffness while maintaining a small footprint. The results are compared to previous X-Bob designs and to folded beam suspensions. Advantages and disadvantages of each design are explained.
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Sathirakul, Korntham, and Robert H. Sturges. "Design of an Isotropic Compliance Mechanism for Off-Axis Peg-in-Hole Insertion." In ASME 1998 Design Engineering Technical Conferences. American Society of Mechanical Engineers, 1998. http://dx.doi.org/10.1115/detc98/dfm-5737.

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Abstract Assembly sequences may require part grasp poses that differ from the implicit assembly insertion axis of RCC-type devices. Since favorable compliant responses accrue only for the insertion axis engineered into the RCC, such “off-axis” poses may obviate its use. The fundamental issue is the creation of an effective compliance that is isotropic in a plane normal to the insertion axis, irrespective of the location of the mechanism. This paper addresses the design of alternative compliant devices, especially an RRR spherical mechanism suitable for industrial application. General compliance requirements are established, mechanism kinematics are developed, and design equations are presented. A laboratory model is described that embodies the desireable features of zero friction, zero backlash, and isotropic stiffness for off-axis assembly tasks.
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Wang, Nianfeng, Zhiyuan Zhang, and Xianmin Zhang. "Design of a Micro-Positioning Stage Using Corrugated Flexure Beam With Cubic Bézier Curve Segments." In ASME 2018 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/detc2018-85345.

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The paper introduces an analytical stiffness matrix method to model a new type of corrugated flexure (CF) beam with cubic Bézier curve segments. In order to satisfy particular design specifications, shape variation for limited geometric envelopes are often employed to alter the elastic properties of flexure hinges. In this paper, cubic Bézier curves are introduced to replace the axis of CF unit to rebuild the CF beam and the micro-positioning stage. Mohr’s integral method is applied to derive the stiffness matrix of the cubic Bézier curve segment. Modeling of the CF unit and the CF beam with cubic Bézier curve segments are further carried out through stiffness matrix method, which are confirmed by finite element analysis (FEA). Discussions about the two control points of the cubic Bézier curve segments are then conducted through search optimization, which highlights the off-axis/axial stiffness ratio and the axial compliance on the position of the two control points, to enable the micro-positioning stage both achieving high off-axis/axial stiffness ratio and large axial compliance. The derived analytical model provides a new option for the design of the CF beam.
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Zou, Ting, and Jorge Angeles. "Decoupling of the Cartesian Stiffness Matrix: A Case Study on Accelerometer Design." In ASME 2011 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/detc2011-47914.

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The 6 × 6 Cartesian stiffness matrix obtained through finite element analysis for structures designed with material and geometric symmetries may lead to unexpected coupling that stems from discretization error. Hence, decoupling of the Cartesian stiffness matrix becomes essential for design and analysis. This paper reports a numerical method for decoupling the Cartesian stiffness matrix, based on screw theory. With the aid of this method, the translational and rotational stiffness matrices can be analyzed independently. The mechanical properties of the decoupled stiffness submatrices are investigated via their associated eigenvalue analyses. The decoupling technique is applied to the design of two accelerometer layouts, uniaxial and biaxial, with what the authors term simplicial architectures. The decoupled stiffness matrices reveal acceptable compliance along the sensitive axes and high off-axis stiffness.
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Trutna, Courtney A., Samantha L. Lipman, Mark L. Palmeri, and Kathryn R. Nightingale. "Large Field-Of-View Shear Wave Elasticity Imaging with Combined On- and Off-Axis Stiffness Estimation for High Frame Rate Hepatic HCC Screening." In 2019 IEEE International Ultrasonics Symposium (IUS). IEEE, 2019. http://dx.doi.org/10.1109/ultsym.2019.8925904.

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Wang, Nianfeng, Fan Yue, Canran Li, and Xianmin Zhang. "Optimization of a 2DOF Positioning Stage Using Corrugated Flexure Units Under Stress Constraints." In ASME 2019 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/detc2019-97758.

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Abstract The paper introduces the design optimization for micro-positioning stage using corrugated flexure (CF) units under stress constraints. The stress state is solved and the maximum displacement under stress constraints is deduced. The natural frequency formula of the micro-positioning stage is further derived from the results of the stiffness matrix. Finally, the stage configurations corresponding to the maximum displacement are optimized by restricting the off-axis/axial stiffness ratio and natural frequency of the stage.
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Goyder, Hugh. "The Difficulty of Modelling Damping in Linear Dynamic Systems." In ASME 2013 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/detc2013-12823.

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The consequences of including damping in linear dynamic systems are investigated. One unexpected consequence is that, unlike an undamped system, modes cannot be found which uncouple the system and can be considered individually. In particular, most damped modes are a source of energy even though only passive damping is being considered. The methodology used is to investigate various sources of damping that have analytical models thus avoiding a dependence on measured data. It is suggested that all damping can be categorised into one of three types which have descriptions in terms of complex variables as i) off-axis pole pairs, ii) symmetry axis poles and iii) symmetry axis branch cuts. One physical example for each type of damping mechanism is identified and analysed. The types of damping covered include viscoelastic materials as well as combinations of dampers and springs in multi-degree of freedom configurations. An important physical model is that of the semi-infinite beam which takes energy off to infinity as well as adding stiffness or inertia to a structure.
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Abrahamsson, Thomas J. S., and Jan Henrik Sällström. "A Spinning Finite Beam Element of General Orientation Analyzed With Rayleigh/Timoshenko/Saint-Venant Theory." In ASME 1994 International Gas Turbine and Aeroengine Congress and Exposition. American Society of Mechanical Engineers, 1994. http://dx.doi.org/10.1115/94-gt-077.

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Linear vibrations are studied for a straight uniform finite beam element of general orientation spinning at a constant angular speed about a fixed axis in the inertial space. The gyroscopic and circulatory matrices and also the geometric stiffness matrix of the beam element are presented. The effect of the centrifugal static axial load on the bending and torsional dynamic stiffnesses is thereby accounted for. The Rayleigh/Timoshenko/Saint-Venant theory is applied, and polynomial shape functions are used in the construction of the deformation fields. Non-zero off-diagonal elements in the gyroscopic and circulatory matrices indicate coupled bending/shearing/torsional/tensional free and forced modes of a generally oriented spinning beam. Two numerical examples demonstrate the use and performance of the beam element.
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Hochmann, David, and Donald R. Houser. "Friction Forces As a Dynamic Excitation Source in Involute Spur and Helical Gearing." In ASME 2000 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2000. http://dx.doi.org/10.1115/detc2000/ptg-14429.

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Abstract Current thought is that the main sources of dynamic excitation in spur and helical gearing occur along the line-of-action and are due to time varying tooth stiffness and static transmission error. This paper examines friction forces as a potential dynamic excitation source in the gear mesh of involute parallel axis spur and helical gearing. The friction forces act in a direction perpendicular to the line-of-action, defined as the off line-of-action direction. To support the claim that friction force is a potential dynamic excitation source, experimental evidence is presented in the form of shaft motions measured near the support bearings in the line-of-action and off line-of-action directions. These experimental results show that the off line-of-action motion is of the same order of magnitude as the line-of-action motion and at times the off line-of-action motion at gear mesh frequency is several times larger than the line-of-action motion. The motions are related to the forces through the bearing stiffness matrix. Other potential explanations of the large off line-of-action shaft motion such as bearing cross coupling phenomena, reduced bearing stiffness, bearing clearances, and system dynamics are examined. The results suggest that through a combination of a small friction force excitation at the gear mesh, and the force transmissibility properties of the gear-bearing system, the friction force can produce forces at the bearing comparable to those generated by transmission error excitations, particularly at low to medium speeds.
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Tehrani, Mehran, Ayoub Y. Boroujeni, Ramez Hajj, and Marwan Al-Haik. "Mechanical Characterization of a Hybrid Carbon Nanotube/Carbon Fiber Reinforced Composite." In ASME 2013 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/imece2013-62251.

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Carbon fiber reinforced polymer composites (CFRPs) are renowned for their superior in-plane mechanical properties. However, they lack sufficient out-of-plane performance. Integrating carbon nanotubes (CNTs) into structures of CFRPs can enhance their poor out-of-plane properties. The present work investigates the effect of adding CNTs, grown on carbon fibers via a relatively low temperature growth technique, on the on and off-axis tensile properties as well as on transverse high velocity impact (∼100 m.s−1) energy absorption of the corresponding CFRPs. Two sets of composite samples based on carbon fabrics with surface grown CNTs and reference fabrics were fabricated and mechanically characterized via tension and impact tests. The on-axis and off-axis tests confirmed improvements in the strength and stiffness of the hybrid samples over the reference ones. A gas gun equipped with a high-speed camera was utilized to evaluate the impact energy absorption of the composite systems subjected to transverse spherical projectiles. Due to the integration of CNTs, intermediate improvements in the tensile properties of the CFRP were achieved. However, the CFRPs’ impact energy absorption was improved significantly.
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