Modeling of an ionic polymer-metal composite beam on human tissue

In this paper, a dynamic model of a simply supported ionic polymer-metal composite (IPMC) beam resting on human tissue is developed. First, the bending moment in the IPMC beam due to the alternative electric potential is derived from Nemat-Nasser's hybrid actuation model. This explicit bending moment expression provides an easy way to estimate the bending capacity of the IPMC. Subsequently, the bending moment expression is incorporated in the analytical solution of beam transverse vibration to describe the response of the IPMC beam to an electric potential. The pressure generated by the IPMC beam on human tissue is then estimated by numerical integration. Comparisons show that the results obtained are comparable with the experimental data in the literature. Finally, to achieve the maximum deflection and total pressure, the optimal electrode length and location are discussed. To increase the flexibility and variety of beam deformation, multiple electrodes are considered. The deflection curve and generative pressure for multiple electrodes are also derived. The developed model is useful not only for biomedical devices that employ IPMC materials but also for any other applications that utilize the vibration of IPMC materials.