In this paper, a comprehensive actuation model for IPMC material is presented. The charge motion within the
polyelectrolyte membrane under a dynamic electric potential is first investigated. Based on the Nernst-Planck equation,
the Poisson's equation and the continuity equation, the charge redistribution under dynamic electric potential is
formulated. Subsequently, the dynamic ion-ion interactions within the polyelectrolyte membrane clusters are presented.
By analyzing the volumetric changes of the membrane clusters due to the electric field induced stresses and the elastic
stresses in the backbones of the membrane, the bending strain and stress are determined. Finally, the bending moment
expression due to the applied electric potential is obtained. By using this bending moment expression, the vibrations of a
cantilevered IPMC sample under different electric excitations are calculated. The actuation characteristics of the IPMC
are then discussed with comparison of experimental observations.
In this paper, the effect of driving frequency on the actuation characteristics of ionic polymer-metal composites (IPMCs)
is studied. The charge motion within the polyelectrolyte membrane under a dynamic electric potential is first formulated
and investigated. Subsequently, the dynamic ion-ion interactions within the polyelectrolyte membrane clusters are
studied. By analyzing the volumetric changes of the membrane clusters due to the electric field induced stresses and the
elastic stresses in the backbones of the membrane, the bending moment expression due to the applied electric potential is
obtained. By using this bending moment expression, the vibrations of an IPMC cantilevered beam subjected to electric
potentials of different frequencies are calculated. The characteristics of the IPMCs behavior are discussed with
comparison with experimental results.
In this paper, a simply supported thin cylindrical shell segment excited by a pair of collocated PZT actuators is studied.
A closed-form solution has been obtained to describe the radial vibration of the shell. Based on this solution, optimal
placement of the pair of PZT actuators in terms of maximizing the vibration of shell is discussed and numerically
verified. It is found that the pattern of the optimal locations of the PZT actuators can be represented by a simple function,
namely, the position mode function (PMF) or their combinations.
In this paper, one-dimensional charge redistribution of IPMC material under dynamic electric potentials is studied. An
analytical solution of normalized charge density is obtained to account for the charge movement under applied electric
potentials. This solution is applicable for both static and dynamic electric potentials applied to IPMC material. Based on
this solution, the thicknesses of boundary layers under dynamic potentials can be calculated. The obtained solutions are
useful for further understanding and modeling of the mechanism of IPMC sensing and actuation.
In this paper, an infinite IPMC cylindrical shell filled with steady-flow fluid is studied. An electric signal is applied on the electrode of IPMC, resulting in vibration of the shell-fluid coupled system. Analytical solutions are obtained by the wave propagation method for the displacement field of the cylindrical shell and the pressure in the contained liquid. The velocity field of the contained liquid due to electric potential excitation is also derived. The numerical example shows that the flow velocity can be enhanced by the applied electric potential. This model may be useful for devices using IPMC cylindrical shell structures with or without contained liquids.
In this paper, a dynamic model of simply supported ionic polymer- metal composite (IPMC) beam resting on human tissues is developed. The IPMC beam is actuated by an alternative electric potential. The bending moment due to electric potential is obtained by Nemat- Nasser's hybrid actuation model. Analytical solution of transverse vibration is obtained to describe the vibration response of IPMC beam to a command of electric potential. Pressure generated by IPMC beam on human tissue is estimated by numerical integration. Comparison shows that the generated pressure is comparable with experimental data from literature. The developed model is useful not only for the biomedical devices that employ IPMC materials but also for any other applications that utilize the vibration of IPMC materials.