Position determination based on electrical capacitance tomography
Purpose - The purpose of this paper is to calculate the two-dimensional (2D) centre position of objects with known shapes based on the reconstruction image of a square sensing area estimated with simulated and measured data by using electrical capacitance tomography (ECT). Design/methodology/approach - A 2D electrostatic finite element model is used to calculate the capacitances between electrode pairs. A reconstruction algorithm with low computation time provides suitable images for subsequent image processing techniques. The results based on numerical data are verified by measurements. Findings - It is possible to calculate the centre position of up to four rods (cross-sectional area about 5 per cent of the measuring area) with an accuracy of 3 per cent in both coordinate directions related to the dimensions of the measuring area. Originality/value - The paper presents an efficient method for position determination of several objects with known shape and uniform permittivity distribution by using ECT measurements with low-cost electronic for industrial application.
capacitance image processing