The grouped node technique as a means of handling large electrode surfaces in electrical impedance tomography

A finite-element method employing a grouped node technique as a means of handling large electrode surfaces in electrical impedance process tomography is presented. The technique groups sets of nodes representing discrete boundary electrodes in a two-dimensional finite-element mesh into corresponding sets of single nodes via a transformation matrix G. The subsequent field solution is obtained based on the new boundary conditions in the standard way after implementing this procedure. Comparison of the resultant boundary voltage profiles from this approach against measurements made on laboratory scale phantoms are reported.