A microstructure-based approach to modeling electrostriction that accounts for variability in spatial locations of domains

Erol, Anil; Ahmed, Saad; Ounaies, Zoubeida; Lockette, Paris von

doi:10.1016/j.jmps.2018.09.024

Cited by 12 publications

(5 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The variable K is the curvature, and z is the distance to the neutral axis. Meanwhile, e E ij e ( ) is the electrostrictive strain as a function of an applied electric field E, determined from a microstructure-based electrostriction model for a nonlinear EAPs [34]. The model is based on averaging the strain-energy density of a semicrystalline microstructure, consisting of amorphous regions that behave like a hyperelastic material, and crystalline regions that behave like dipoles interacting with each other.…”

Section: Model Frameworkmentioning

confidence: 99%

Multi-objective optimization of a multi-field actuated, multilayered, segmented flexible composite beam

Erol

Lockette

Frecker

2019

Smart Mater. Struct.

Self Cite

View full text Add to dashboard Cite

Multi-layered, self-actuated devices have been the focus of recent studies due to their ability to exhibit large displacements and achieve complex shapes. Such devices have been constructed using active materials responsive to varying stimuli including electro-active and magneto-active materials to perform useful functions and achieve a wider variety of target shapes compared to single-field actuated unimorph/bimorph structures. However, fabrication of these devices for experimentation is time-consuming and expensive, which warrants the use of simulations as a means of designing high-performing structures. This work seeks to optimize structures employing materials response to magnetic and electric fields for multiple objective functions selected based on the needs of soft robotics applications such as grippers. A multi-objective optimization problem is constructed, utilizing a model developed for any arbitrary number of segments, layers, and material types, accommodating for large displacements and simultaneously applied fields. Three objective functions are chosen: (1) target shape approximation, based on the errors between the coordinates of the computed and desired shapes, (2) cost based on volume of magnetic material, and (3) work performed on a tip-force. The arbitrary optimization problem is reduced to a specific case study containing eight segments to alleviate the computational cost of an unwieldy number of parameters. The parameters are narrowed to: (1) segment lengths, (2) magnetic material in each magneto-active layer. The structure is pre-set to three material types: electro-active polymer, magneto-active elastomer, and a passive substrate. The case study's optimization problem is performed by a genetic algorithm developed by MATLAB for multiple objective functions. The results of the optimization on the case study are analyzed by studying the feasible designs on the Pareto front of the objective functions. Different trade-offs between objective functions are identified, and various feasible designs are found more suitable than others, based on the needs and priorities of an application.

show abstract

Section: Model Frameworkmentioning

confidence: 99%

Multi-objective optimization of a multi-field actuated, multilayered, segmented flexible composite beam

Erol

Lockette

Frecker

2019

Smart Mater. Struct.

Self Cite

View full text Add to dashboard Cite

show abstract

“…Electrostriction is the fundamental electromechanical coupling in all materials, since all materials possess atoms, ions, molecules, or domains that are either polarized or polarizable, application of an electrical excitation (field or induced polarization) distorts the charge distribution, which is then coupled to distortion of the actual dimensions. In short, elastic strain in the material resulted from distortion of the bond lengths, bond angles, electron distribution functions, or electric dipoles with an applied electric stress (Erol et al, 2019;Gaikwad et al, 2019;Gareeva et al, 2019;Jin et al, 2019;Kumar and Sarangi, 2019). In present investigation, model prediction for the characteristics of polarization in a dielectric material exhibiting piezoelectricity and electrostriction was developed and employed for the monitoring, prediction and simulation using derived mathematical equations as well as MATLAB computer simulation software.…”

Section: Introductionmentioning

confidence: 99%

Mathematical model to predict the characteristics of polarization in dielectric materials: The concept of piezoelectrcity and electrostriction

Int¹

2019

Preprint

View full text Add to dashboard Cite

Model was developed for the prediction of polarization characteristics in a dielectric material exhibiting piezoelectricity and electrostriction based on mathematical equations and MATLAB computer simulation software. The model was developed based on equations of polarization and piezoelectric constitutive law and the functional coefficient of Lead Zirconate Titanate (PZT) crystal material used was 2.3×10 -6 m (thickness), the model further allows the input of basic material and calculation of parameters of applied voltage levels, applied stress, pressure, dielectric material properties and so on, to generate the polarization curve, strain curve and the expected deformation change in the material length charts. The mathematical model revealed that an application of 5 volts across the terminals of a 2.3×10 -6 m thick dielectric material (PZT) predicted a 1.95×10 -9 m change in length of the material, which indicates piezoelectric properties. Both polarization and electric field curve as well as strain and voltage curve were also generated and the result revealed a linear proportionality of the compared parameters, indicating a resultant increase in the electric field yields higher polarization of the dielectric materials atmosphere.Capsule Summary: Mathematical model was developed and employed for the prediction of polarization in dielectric materials using the concept of piezoelectrcity and electrostriction. Electric field effects on the polarization of the dielectric materials, as well as results revealed the change in length of the dielectric material demonstrating piezoelectric characteristics of the PZT crystal material. Cite This ArticleAs: C. P. Ukpaka. Mathematical model to predict the characteristics of polarization in dielectric materials: The concept of piezoelectrcity and electrostriction. Chemistry International 5(3) (2019) 232-240. https://doi.org/10.5281/zenodo.2525583 to the field (Amjad et al., 2019; Costa et al.

show abstract

“…Dielectric elastomers (DEs) respond to electric fields with large deformations and can be used to convert between electrical and mechanical energy. Therefore, DEs are promising for applications in energy harvesting, biomedical devices, and soft, biologically-inspired robotics [1][2][3][4][5][6][7][8][9][10][11][12][13]. The quintessential example of a DE actuator (DEA) is a thin DE film sandwiched between two compliant electrodes.…”

Section: Introductionmentioning

confidence: 99%

Nonlinear Statistical Mechanics Drives Intrinsic Electrostriction and Volumetric Torque in Polymer Networks

Grasinger,

Majidi,

Dayal

2021

Preprint

View full text Add to dashboard Cite

Statistical mechanics is an important tool for understanding polymer electroelasticity because the elasticity of polymers is primarily due to entropy. However, a common approach for the statistical mechanics of polymer chains, the Gaussian chain approximation, misses key physics. By considering the nonlinearities of the problem, we show a strong coupling between the deformation of a polymer chain and its dielectric response; that is, its net dipole. When chains with this coupling are cross-linked in an elastomer network and an electric field is applied, the field breaks the symmetry of the elastomer's elastic properties, and, combined with electrostatic torque and incompressibility, leads to intrinsic electrostriction. Conversely, deformation can break the symmetry of the dielectric response leading to volumetric torque (i.e., a couple stress or torque per unit volume) and asymmetric actuation. Both phenomena have important implications for designing high-efficiency soft actuators and soft electroactive materials; and the presence of mechanisms for volumetric torque, in particular, can be used to develop higher degree of freedom actuators and to achieve bioinspired locomotion. FIG. 1. Dielectric elastomer actuator with dimensions of length in the ê1 and ê2 directions, and thickness t in the ê3 direction, where t : (a) undeformed configuration; (b) a voltage difference is applied across the electrodes on the top and bottom surfaces and, as a result, the actuator contracts across its thickness and expands in the plane orthogonal.

show abstract

A microstructure-based approach to modeling electrostriction that accounts for variability in spatial locations of domains

Cited by 12 publications

References 46 publications

Multi-objective optimization of a multi-field actuated, multilayered, segmented flexible composite beam

Multi-objective optimization of a multi-field actuated, multilayered, segmented flexible composite beam

Mathematical model to predict the characteristics of polarization in dielectric materials: The concept of piezoelectrcity and electrostriction

Nonlinear Statistical Mechanics Drives Intrinsic Electrostriction and Volumetric Torque in Polymer Networks

Contact Info

Product

Resources

About