Abstract
This paper describes a method for estimating the internal distribution of electrical impedance of a compound object from the potential data on the boundary. The boundary potential are measured while a set of currents are applied to a number of electrodes on the periphery of the object. The current data are also presented to a finite element (FE) model of the object, with an initial guess of internal impedance distribution, and then the potential distribution is calculated. An objective function is introduced to define the error between the boundary potential of the FE model and that of the real object. The impedance parameters of the FE model are iteratively modified so as to minimize the objective function, using the Newton-Raphson method. To validate the approach, a computer simulation and an experiment were performed in which resistive-capacitive materials were considered.
