A new sensing method for Electrical Capacitance Tomography

A new sensing method, termed Multiple Excitation Capacitance Polling (MECaP), has been developed to improve the efficiency of Electrical Capacitance Tomography (ECT). Instead of applying one excitation signal to an electrode at a time, the MECaP technique progressively applies an increasing number of excitation signals to multiple electrodes, and measures the capacitance values simultaneously, thereby increasing the scanning speed significantly. A numerical model of a MECaP-based sensor system has been developed using the Finite Element method. Results obtained from simulation and experiment demonstrated the effectiveness and efficiency of the new sensing technique and its applicability to a broad range of commercial and industrial applications where capacity measurement provides an efficient means for non-invasive monitoring of dynamic processes.