Design of Magnetic Induction tomography system using 12 transmitter and receiver coils

Abstract

A Magnetic Induction Tomography (MIT) system, one of tomography systems with non-invasive modality, which uses magnetic field induction to reconstruct the distribution of electrical conductivity in an object material has been developed. MIT is a low resolution tomography technique based on the rate of changes in the magnetic flux due to the test material with respect to the main alternating magnetic flux. In this study, the MIT system was designed using 12 receiver and transmitter coils, with an excitation signal in the form of a sinusoidal electrical signal with amplitude of 5 V, frequency of 2 MHz. The coil used has 100 turns of copper wire, with inner diameter of 15.5 mm, and length of 4 cm. Coils are arranged in a circle with an inner diameter of 12 cm and each coil forms a 30 degree angle to each other. The magnitude of the induced electrical voltage at the receiving coil that is influenced by the rate of change of magnetic flux on the transmitter coil, is also affected by the permeability of the medium between the transmitter and receiver coil. The induction electrical voltage on the receiving coils are measured by the MIT data acquisition system, and then the image reconstruction process is carried-out based on those data. This MIT system has been tested by placing an object material in the form of an empty cylindrical iron and also an empty box-shaped iron. This research has been able to get the 2D reconstruction image in accordance with the actual shape of the test material object but not yet perfect.