Application of electro mechanical stiffness modulation in biomimetic hair flow sensors

We propose a new electromechanical interfacing scheme to improve the low-frequency response of energy buffering type transducers. The method is based on periodic modulation of the stiffness in the sensory system which allows to up-convert the signals of interest to frequencies where measurement is less troubled by noise or other detrimental effects. We demonstrate this principle by means of capacitive artificial hair flow sensors, where we modulate the rotational spring stiffness by periodic electrostatic spring softening (ESS), such that a replica of the original signal is formed around the modulation frequency. We show that using this replica we gain a substantial improvement of the low frequency signal-to-noise ratio and sensing threshold.