Abstract：The output signal quality of a 12-electrode co-planar capacitive sensor (CCS) for each electrode pair was systematically evaluated by finite element simulations and experiments.The results showed that the output signal quality of the electrode pairs was mainly related to the electrode spacing and the contact edge length.Reducing the electrode spacing and increasing the contact edge length are beneficial for improving the output signal quality.An electrode utilization rate (EUR) method was proposed to evaluate the output signal quality of CCS.The output signal quality of CCS with different number of independent electrodes was evaluated by combining EUR.According to the findings,adding more independent electrodes barely improved the useful output information and generated a significant amount of noise.The EUR value declines as the number of independent electrodes rises,which implies that adding more independent electrodes lowers the output signals quality.The outcomes of the image reconstruction were in agreement with the results of the EUR analysis.The effectiveness of EUR for evaluating the output signal quality of multi-electrode CCS was verified experimentally and in simulation.The methods and conclusions may provide a reference for CCS array electrode design and output signal processing.
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2024, Vol. 45 
