Localization of Miniature Ingestible coils using Tri-Polar Plane Type (TPT) Transmitter

This paper presents a method to locate miniature ingestible coils using mutual inductance (MI) measurement with a tripolar-plane-type (TPT) transmitter. Steepest Descent is used to calculate the real-time miniature coil location. The objective function is constructed using an analytical MI model that takes arbitrary translational and angular misalignment into consideration. The model accounts for the planar structure of the TPT coil and provides an approximate co-centered filament model that is accurate and computationally light. The location Root Mean Square Error (RMSE) of 0.2cm and 1.67cm can be achieved with perfectly accurate MI measurement and with +/- 10% uniformly random MI inaccuracy when using one helical receiving coil. If a second orthogonal receiving coil is used, the RMSE is reduced to 0.04cm and 0.7cm without and with MI measurement inaccuracy, respectively.