A 1000-measurement frames/second ERT data capture system with real-time visualization

This paper describes the design of a 16-electrode high-speed (1000 frames/s) electrical resistance tomography system with real-time visualization. The instrument utilizes a switched dc current pulse technique in conjunction with parallel data acquisition to achieve the high-data capture rates. The reconstruct algorithm is implemented using a single iteration Newton-Raphson method, which executes in under 1 ms. Data sets are presented that verify its operation. A calibration technique is described which improves the sensitivity of the current pulse measuring system and allows phenomena such as the dynamics of nonuniform slurries and gas distribution in aeration systems to be investigated. Furthermore, the calibration scheme described compensates significantly for the effect of impellers and baffles present in the measuring tank and allows more accurate reconstructions to be performed in the areas of interest.