Characterization of piezoelectric film sensors for tongue-computer interface

In this paper we examine the pressure detection quality and signal clarity for two types of piezoelectric film sensors. One sensor was coated with polydimethylsiloxane (PDMS) while the other remained uncoated. Our goal was to determine how coating the sensor with PDMS would affect sensor performance. Our long-term goal is to develop a tongue-computer interface using piezoelectric film sensors. Coating of the sensors is necessary to provide biocompatibility. In our experiments, a mechanical push-arm was used to apply consistent pressure on the sensors and generate constant output voltage peaks. The pressure levels applied by the apparatus and the tongue were similar. The output signal of the coated piezoelectric sensor showed inconsistency, yielding a much higher standard deviation than the uncoated sensor. Both sensors provided a detectable difference between an applied pressure condition and the rest state.