Electrical impedance tomography system using 3D finite element algorithm

A 3D finite element model is used for solving the problem of nonlinearity and multidimensional distribution of electric field in the reconstruction of impedance tomographic image of a conductive object. The boundary values of the problem are the small current injected through the cross-section and voltage measured around the object. The Newton-Raphson method is used for varying the resistivity distribution to fit the set of the measured voltage. The calculated resistivity of each elements can be reconstructed the image of cross-section. The experimental results with saline tank phantom are shown the reduction of the error, comparing to 2D model, due to the position of electrodes around the object and distribution of electric field along the thickness of the object.