Algebraic summation of eigenstates as a novel output metric to extend the linear sensing range of mode-localized sensors

Frequency-modulated MEMS resonant sensors have been widely used in a variety of sensing applications. This recently emerging sensing mechanism, based on the mode localization of weakly coupled resonators, provides improved sensitivity of more than two orders of magnitude by selecting eigenstate or amplitude ratio as the output metric. However, the loci veering property of the new readout limits the linear sensing range of the mode-localized sensors. In this paper, we propose for the first time that using the algebraic summation of the amplitude ratios of the two vibration modes can enhance the linear sensing range to full-scale range. The measured linear sensing range ([-12, -2] N/m) of selecting algebraic summation as the output metric is more than 2 times larger than that ([-12, -8] N/m) of reading the amplitude ratio of a certain mode.