Flexible Impedance Sensor for In-Line Monitoring of Water and Beverages

A safety impedance micro-sensor based on flexible electrodes for continuous monitoring of the surface cleanness of pipes of small diameter (down to few mm) handling drinkable fluids is presented. It allows discrimination between biofilm and limescaling, grants high resolution (few μm in thickness) and enables early warning and predictive (closed-loop) maintenance. It is coupled with a temperature and fluid conductivity probes in order to calibrate for their fluctuations. The current prototypal electronics, measuring impedance in the MHz range, can be scaled towards low-cost and low-power pervasive implementations. Preliminary experimental results showing the consistence with non-curved geometries are presented.