This paper presents a distributed model of an IPMC (Ionomeric Polymer-Metal Composite). Unlike other
electromechanical models of an IPMC, the distributed nature of our model permits modelling the non-uniform bending
of the material. Instead of modeling solely the tip deflection of the material, we model the changing curvature. Our
model of the IPMC describes the actuator or sensor as a distributed one-dimensional RC transmission line. The behavior
of the IPMC at its each particular position in time-domain is described by a system of Partial Differential Equations.
(PDE). The parameters of the PDE-s have a clear physical interpretation: the conductivity of the electrodes, the
pseudocapacitance of the arising double-layer at the boundary of the electrodes, the electric current caused by electrode
reactions etc. The electromechanical coupling between the electrical parameters and the bending motion is implemented
by means of distribution of electric current along the material in a time domain. The distributed nature of the model
permits predicting the non-uniform bending of the IPMC actuators in time domain or to reconcile the output of an IPMC-based
position sensor with its shape. Taking into account several nonlinear parameters, the model is consistent with the
experimental results even when the inflexion of the actuator or sensor is large or the water electrolysis appears.
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