Nonlinear Structural Dynamics of Macro-Fiber Composite Cantilevers for Resonant Actuation

Macro-fiber composite (MFC) piezoelectric materials are used in a variety of applications employing the converse piezo-electric effect, ranging from bioinspired actuation to vibration control. Most of the existing literature to date considered linear material behavior for geometrically linear oscillations. However, in many applications, such as bioinspired locomotion using MFCs, material and geometric nonlinearities are pronounced and linear models fail to represent and predict the governing dynamics. The predominant types of nonlinearities manifested in resonant actuation of MFC cantilevers are piezoelectric softening, geometric hardening, inertial softening, as well as internal and external dissipative effects. In the present work, we explore nonlinear actuation of MFC cantilevers and develop a mathematical framework for modeling and analysis. An in vacuo actuation scenario is considered for a broad range of voltage actuation levels to accurately identify the sources of dissipation. Several experiments are conducted for an MFC bimorph cantilever, and model simulations are compared with nonlinear experimental frequency response functions under resonant actuation. The resulting experimentally validated framework can be used for simulating the dynamics of MFCs under resonant actuation, as well as parameter identification and structural optimization for nonlinear operation regime.

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Resonant Nonlinearities of Macro-Fiber Composite Cantilevers in Energy Harvesting

Volume 1: Development and Characterization of Multifunctional Materials; Mechanics and Behavior of Active Materials; Bioinspired Smart Materials and Systems; Energy Harvesting; Emerging Technologies ◽

10.1115/smasis2017-3931 ◽

2017 ◽

Cited By ~ 1

Author(s):

David Tan ◽

Paul Yavarow ◽

Alper Erturk

Keyword(s):

Energy Harvesting ◽

Fiber Composite ◽

Rectangular Cross Section ◽

Electrical Power ◽

Interdigitated Electrodes ◽

Modeling And Analysis ◽

Dissipative Effects ◽

Macro Fiber Composite ◽

Electrical Loads ◽

Electrical Power Output

We explore the modeling and analysis of nonlinear non-conservative dynamics of macro-fiber composite (MFC) piezo-electric structures, guided by rigorous experiments, for resonant vibration-based energy harvesting, as well as other applications leveraging the direct piezoelectric effect, such as resonant sensing. The MFCs employ piezoelectric fibers of rectangular cross section embedded in kapton with interdigitated electrodes to exploit the 33-mode of piezoelectricity. Existing frameworks for resonant nonlinearities have so far considered conventional piezoceramics that use the 31-mode of piezoelectricity. In the present work, we develop a framework to represent and predict nonlinear electroelastic dynamics of MFC bimorph cantilevers under resonant base excitation. The interdigitated electrodes are shunted to a set of resistive electrical loads to quantify the electrical power output. Experiments are conducted on a set of MFC bimorphs over a broad range of mechanical excitation levels to identify the types of nonlinearities present and to compare the model predictions and experiments. The experimentally observed interaction of material softening and geometric hardening effects, as well as dissipative effects, is captured and demonstrated by the model.

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Modeling and analysis of dynamic structure with macro fiber composite for energy harvesting

Materials Today Proceedings ◽

10.1016/j.matpr.2020.05.390 ◽

2020 ◽

Vol 33 ◽

pp. 3481-3485

Author(s):

M.P. Saravanan ◽

K. Marimuthu ◽

P. Sivaprakasam

Keyword(s):

Energy Harvesting ◽

Fiber Composite ◽

Dynamic Structure ◽

Modeling And Analysis ◽

Macro Fiber Composite

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Parametric Analysis of Structural Properties of a Rectangular Partially-Clamped Wing

ASME 2020 Conference on Smart Materials, Adaptive Structures and Intelligent Systems ◽

10.1115/smasis2020-2212 ◽

2020 ◽

Author(s):

Mohammad Katibeh ◽

Onur Bilgen

Keyword(s):

Parametric Analysis ◽

Piezoelectric Materials ◽

Fiber Composite ◽

Structural Response ◽

Critical System ◽

Resonant Frequencies ◽

System Parameters ◽

Composite Substrate ◽

Macro Fiber Composite ◽

Actuation Systems

Abstract The so-called solid-state ornithopter concept seeks to employ piezoelectric materials to generate flapping motion instead of relying on conventional mechanisms and multi-component actuation systems. The motion can be induced on a wing-like partially-clamped composite substrate with a piezocomposite device (i.e. the Macro-Fiber Composite actuator.) In this research, a design for a flapping wing is proposed based on the analysis of critical system parameters such as geometric properties and boundary conditions. A series of finite element simulations are conducted based on the variation of those parameters. Consequently, the effects of parameters on the structural response is studied. Also, modal analysis is done to examine the effects of geometric parameters on the resonant frequencies of the system. Heaving and pitching responses are examined.

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New Efficient Technique for Finite Element Modeling of Macro Fiber Composite Piezoelectric Materials

Materials Science Forum ◽

10.4028/www.scientific.net/msf.998.221 ◽

2020 ◽

Vol 998 ◽

pp. 221-226

Author(s):

Diaa Emad ◽

Mohamed A. Fanni ◽

Abdelfatah M. Mohamed

Keyword(s):

Finite Element ◽

Piezoelectric Materials ◽

Fiber Composite ◽

Computational Time ◽

Time Cost ◽

Element Analysis ◽

Element Mesh ◽

Detailed Model ◽

Macro Fiber Composite ◽

Computational Time Cost

A lot of interest to simulate piezocomposite actuators with finite element method has been increased recently. However, there are still open questions regarding the modeling methodology, accuracy, and computational time cost. In this work, a new technique for modeling macro fiber composite piezoelectric actuator by finite element analysis is proposed. The presented technique models the piezocomposite actuator as a simple monolithic piezoceramic material with just two electrodes along its longitudinal extremes instead of using the actual large number of electrodes which results in very fine finite element mesh with high computational time cost. The proposed technique is validated successfully by comparing its results with those of the actual detailed model as well as with the published experimental results and manufacturer’s data.

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Control Force Enhancement of Conical Shells Using Piezoelectric Macro-Fiber Composite

Volume 4B: Dynamics, Vibration and Control ◽

10.1115/imece2013-64319 ◽

2013 ◽

Author(s):

H. Li ◽

H. Y. Li ◽

H. S. Tzou

Keyword(s):

Conical Shell ◽

Piezoelectric Materials ◽

Fiber Composite ◽

Bending Moment ◽

Longitudinal Direction ◽

Control Force ◽

Force Enhancement ◽

Actuation Force ◽

Macro Fiber Composite ◽

Converse Piezoelectric Effect

In piezoelectric coupled shells, the distributed actuation force usually consists of four components, including the membrane force and bending moment in the longitudinal direction, and the membrane force and bending moment in the circumferential direction. For commonly used bi-axial piezoelectric materials, such as PZT and PVDF, these four components may have phase difference of π or −π. This leads to force cancellation and reduces the overall control effectiveness. Supposing that one piezoelectric actuator is uni-axial, for example only d31 is not equal to zero, and then this actuator will generate actuation force with the first two components or the latter two, depending on the actuator configuration and the shell geometry/modes. Accordingly the force cancellation can be avoided or minimized. In this research, the Macro-Fiber Composite (MFC) actuators are used as uni-axial actuators. The dynamic equation of a conical shell is firstly given. Then the actuation force is derived based on the converse piezoelectric effect and thin shell assumptions. Three types of the MFC actuators are considered, including MFC-P1, MFC-P2 and MFC-P3. Case studies are performed to evaluate the distributed actuation forces. Both axial and transverse vibrations of the conical shell are formulated to study the force cancellation of various shell modes, and the payload effects are considered in the analysis. The results show that, by using the MFC actuators, actuation force can be enhanced because force cancellation is avoided. The force enhancement becomes even more significant for membrane dominated modes, such as axial modes of shells with heavy payloads.

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Fatigue Investigation of Elastomeric Structures

Tire Science and Technology ◽

10.2346/1.3481658 ◽

2010 ◽

Vol 38 (3) ◽

pp. 194-212 ◽

Cited By ~ 11

Author(s):

Bastian Näser ◽

Michael Kaliske ◽

Will V. Mars

Keyword(s):

Fatigue Crack ◽

Fatigue Crack Growth ◽

Crack Growth ◽

Material Behavior ◽

Period Effect ◽

Numerical Representation ◽

Material Force ◽

Strain Behavior ◽

Dissipative Effects ◽

Elastomeric Materials

Abstract Fatigue crack growth can occur in elastomeric structures whenever cyclic loading is applied. In order to design robust products, sensitivity to fatigue crack growth must be investigated and minimized. The task has two basic components: (1) to define the material behavior through measurements showing how the crack growth rate depends on conditions that drive the crack, and (2) to compute the conditions experienced by the crack. Important features relevant to the analysis of structures include time-dependent aspects of rubber’s stress-strain behavior (as recently demonstrated via the dwell period effect observed by Harbour et al.), and strain induced crystallization. For the numerical representation, classical fracture mechanical concepts are reviewed and the novel material force approach is introduced. With the material force approach at hand, even dissipative effects of elastomeric materials can be investigated. These complex properties of fatigue crack behavior are illustrated in the context of tire durability simulations as an important field of application.

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Material parametrization of natural rubber based compound and characterization of crack propagation under consideration of dissipative effects

Journal of Rubber Research ◽

10.1007/s42464-021-00094-8 ◽

2021 ◽

Author(s):

Dan Pornhagen ◽

Konrad Schneider ◽

Markus Stommel

Keyword(s):

Energy Dissipation ◽

Crack Propagation ◽

Natural Rubber ◽

Experimental Tests ◽

Material Behavior ◽

Prony Series ◽

Material Forces ◽

Cracking Behavior ◽

Dissipative Effects

AbstractMost concepts to characterize crack propagation were developed for elastic materials. When applying these methods to elastomers, the question is how the inherent energy dissipation of the material affects the cracking behavior. This contribution presents a numerical analysis of crack growth in natural rubber taking energy dissipation due to the visco-elastic material behavior into account. For this purpose, experimental tests were first carried out under different load conditions to parameterize a Prony series as well as a Bergström–Boyce model with the results. The parameterized Prony series was then used to perform numerical investigations with respect to the cracking behavior. Using the FE-software system ANSYS and the concept of material forces, the influence and proportion of the dissipative components were discussed.

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