Weak stimuli corresponding to respiration, swallowing, chewing, finger flexion, muscle vibration, and joint movements had been efficiently measured by exploiting a piezoelectric sensor developed by Wang et al. [21]. The sensor was manufactured from poly(vinylidene fluoride–trifluoro ethylene) multi-walled carbon nanotubes (p(VDF–TrFE)/MWCNTs) grown in their β-phase