The development of
a flexible electronic skin (e-skin) highly sensitive
to multimodal vibrations and a specialized sensing ability is of great
interest for a plethora of applications, such as tactile sensors for
robots, seismology, healthcare, and wearable electronics. Here, we
present an e-skin design characterized by a bioinspired, microhexagonal
structure coated with single-walled carbon nanotubes (SWCNTs) using
an ultrasonic spray method. We have demonstrated the outstanding performances
of the device in terms of the capability to detect both static and
dynamic mechanical stimuli including pressure, shear displacement,
and bending using the principles of piezoresistivity. Because of the
hexagonal microcolumnar array, whose contact area changes according
to the mechanical stimuli applied, the interlock-optimized geometry
shows an enhanced sensitivity. This produces an improved ability to
discriminate the different mechanical stimuli that might be applied.
Moreover, we show that our e-skins can detect, discriminate, and monitor
various intensities of different external and internal vibrations,
which is a useful asset for various applications, such as seismology,
smart phones, wearable human skins (voice monitoring), etc.