Linear constitutive model of ionic polymer bender transducers

Kenneth M. Newbury; Donald J. Leo

doi:10.1117/12.484401

Translator Disclaimer

28 July 2003 Linear constitutive model of ionic polymer bender transducers

Kenneth M. Newbury, Donald J. Leo

Author Affiliations +

Proceedings Volume 5051, Smart Structures and Materials 2003: Electroactive Polymer Actuators and Devices (EAPAD); (2003) https://doi.org/10.1117/12.484401
Event: Smart Structures and Materials, 2003, San Diego, California, United States

Abstract

A linear constitutive model for ionic polymer benders is developed to model sensing and actuation properties of ionic polymer transducers. The model is based on a set of linear coupled equations that relate stress, strain, applied field, and electric displacement. The constitutive equations are integrated to obtain an impedance model that is a function of transducer geometry and three material parameters. The material parameters are the electric permittivity, elastic modulus, and electromechanical coupling coefficient. Experiments are performed to determine the three material parameters from measured data on cantilever transducers. Experiments demonstrate that the strain coefficient of an ionic polymer transducer is on the order of 20,000 to 30,000 pm/V. Ionic polymers have very low coupling coefficient due to the large compliance and excessively high permittivity and the low speed of sound (≈ 250 to 300 m/s) limits the actuation bandwidth of any device constructed from the material. Furthermore, ionic polymers exhibit dielectric relaxation at higher frequencies and the coupling coefficient exhibits a sharp decrease below approximately 0.1 Hz. These characteristics limit the low frequency actuation capability of the material.

Citation Download Citation

Kenneth M. Newbury and Donald J. Leo "Linear constitutive model of ionic polymer bender transducers", Proc. SPIE 5051, Smart Structures and Materials 2003: Electroactive Polymer Actuators and Devices (EAPAD), (28 July 2003); https://doi.org/10.1117/12.484401

ACCESS THE FULL ARTICLE