Modifying Electrical Impedance Tomography System (3)

Presenter : Yu-Chun HuaPresenter : Yu-Chun Hua Adviser : Dr. Ji-Jer Huang Adviser : Dr. Ji-Jer Huang Date : 99.12.09Date : 99.12.09

D. Boundary Potentials MeasurementsA 1 mA, 50 kHz constant current signal is injected to the phantom boundary

The surface potentials developed are measured using neighboring method of electrode switching protocol

Boundary data measurement with practical biological phantom

D. Boundary Potentials MeasurementsBoundary potentials are also measured for a phantom with and without extra water column above and below the electrode array level.

The measured potential data are compared with the calculated potential data.

Boundary data measurement with a phantom having extra water column above and below

the electrode array level.

Paper review(2) resultsPaper review(2) resultsThe differential potential is calculated using our forward solver with the phantom specifications provided by Ider et al

Vds Curve Compared with Ider et al Data

Paper review(2) resultsPaper review(2) resultsVds: surface potentialVdm: measured data = differential potentialCME: Common Mode ElectrodeCGE : Central Ground Electrode

Vdm data with and with CGE after Calibration

Materials and Methods System Block diagram

Future worksPaper review

Build a hardware howland circuit

Modified EIT system (digital control)

References[1] R. A. Stiz, P. Bertemes-Filho, A. Ramos, V. C. Vincence.

“Wide Band Howland Bipolar Current Source using AGC Amplifier “IEEE LATIN AMERICA TRANSACTIONS, VOL. 7, NO. 5, SEPTEMBER 2009

[2] From: Tushar Kanti Bera and J. Nagaraju ”﹐ A Simple Instrumentation Calibration Technique for Electrical Impedance Tomography (EIT) Using A 16-Electrode Phantom ” 5th Annual IEEE Conference on Automation Science and Engineering Bangalore, India, August 22-25, 200