Conducting polymers are active materials that exhibit an interesting bidirectional electromechanical coupling, where an input voltage results in the displacement of the film and a voltage is produced when a displacement is applied to the film. Mechanical deformation of the transducer by external mechanical loads causes movement of ions, and the generation of voltages. In this work, a dual sensing and actuation model for conducting polymer is described. The model comprises an RC lumped circuit, representing the electrochemical model, a mechanical model described by a dynamic Euler – Bernoulli beam theory, and an empirical strain-to-charge ratio. All three submodels are presented in a self-consistent Bond Graph formalism. The predictions of this model are then demonstrated by comparing with the experimental sensing and actuation results of a 17 µm thin poly(3,4-ethylenedioxythiophene) – based trilayer transducer, showing that the complete electromechanical model elucidates an effective approach to describe both sensing and actuation.
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