Using bundles of vertical zinc oxide nanowires, researchers
have fabricated arrays of piezotronic transistors capable of converting
mechanical motion directly into electronic controlling signals. The arrays
could help give robots a more adaptive sense of touch, provide better security
in handwritten signatures and offer new ways for humans to interact with
electronic devices.
The arrays include more than 8,000 functioning piezotronic
transistors, each of which can independently produce an electronic controlling
signal when placed under mechanical strain. These touch-sensitive transistors –
dubbed “taxels” – could provide significant improvements in resolution,
sensitivity and active/adaptive operations compared to existing techniques for
tactile sensing. Their sensitivity is comparable to that of a human fingertip.