International Society for Industrial Process Tomography

Low Cost Design of Electrical Impedance Tomography Hardware System for Industrial Application

Chenning Wu^1*, Manuchehr Soleimani¹

¹Engineering Tomography Laboratory (ETL), Department of Electronic and Electrical Engineering,

University of Bath, Bath, UK

^*Email: cnw24@bath.ac.uk

ABSTRACT

Electrical impedance tomography (EIT) is a non-invasive imaging modality that images the conductivity (electrical impedance) distribution within the subject.by injecting current into the boundary of a medium and collecting the voltage measurements. It features being fast, inexpensive and safe that has gained great popularity in process tomography field. One of the most popular industrial applications is two-phase flow analysis, which maps the concentration and velocity distributions of the second phase. The success of it is largely limited by the EIT instrumentation, which is desirably capable of achieving real time data capturing and transmission. This work proposed a practical design of a 16 channel, low-cost EIT hardware system targeting at waste water flow measurement application. The detailed hardware design is presented in a modular fashion, including a constant current source suitable for industrial field, voltage measurement module and a user interface unit.The overall system performance is verified by phantom tests using saline and plastic water bottle. Image reconstruction was carried out by both the traditional Tikhonov regularization algorithm and Total Variation algorithm. Further improvement will also be stated for next generation design.

Keywords Electrical impedance tomography (EIT), data acquisition, EIT instrumentation

Industrial Application General