International Society for Industrial Process Tomography

4D Scanning for Planar Array ECT

C. T. Chittenden^*, M. Soleimani

Electrical Tomography Lab, University of Bath, Bath, UK

^*Email: C.Tholin-Chittenden@bath.ac.uk

ABSTRACT

Temporal tomography imaging involves taking multiple images of the same area and tracking changes. This has been done with good results using Electrical Impedance Tomography (EIT) (Adler, Dai and Lionheart, 2007) as well as Electrical Capacitance Tomography (ECT) (Soleimani et al., 2009). However both of these focus the sensor on a single area and measure over time but in a landmine detection scenario, and other applications, it is the sensor which must move over an area. This allows for not only 4D reconstruction using multiple ‘frames’ of measurement data but also to build up a much larger imaging area than the size of the sensor.

This paper proposes a method which uses temporal image reconstruction whilst also moving the sensor over an area to reconstruct a more accurate and stable permittivity distribution. There is overlap of viewing regions between each movement of the sensor and so the reconstruction Jacobian and capacitance measurements are concatenated to then produce much larger reconstructions. This is referred to as ‘scanning’ with the aim to build up an image of the entire ‘scanning’ area. This method is better than stitching together individual images next to each other as each voxel of the image is reconstructed from multiple measurements. Initial simulation work has shown that this works much better than non-scanning where only a snapshot of the viewing area is reconstructed. Practical testing also showed that this works with real data and both shape and location reconstruction of the inclusion are improved.

Keywords 4D ECT Landmine Scanning

Industrial Application General