With the advent of the technology for building up an adequately large electrical field in polymer foams, an ultra-thin Pressure Sensor, which can be woven into sensitive textiles, is the new creation of physicists from Austria and the U.S. TFTs and ferroelectrets, which are thin films of polymer foams, are unified to pull off the cause, which is capable of switching back and forward in reaction to pressure.
According to Siegfried Bauer from the Institute of Experimental Physics at the Johannes Kepler University in Linz,
The key factor is the correct coating of the components. We applied a propylene foam over a TFT on a polyimide base. These are the type of TFTs we know from flatscreens. The polymer propylene foam is the actual sensor. When pressed, the differently charged sides of the individual cavities in the foam converge and produce an electrical signal.
The great thing about this combination is that the transistor switches only temporarily. If the pressure on the propylene layer decreases, the transistor reverts to its original state. Previously similar experiments only created permanent switching of the transistor. The transistor did not revert to its original state. That is naturally not ideal for a pressure sensor. It would still generate a signal even if the pressure were released.
After intense testing in Haute couture from the experimental physics lab, pressure sensors are now ready for interactive clothing, which can be used in sickbays to know whether the patients have left their beds or not. Due to their sensitivity and low production costs, pressure-sensitive switches have a good assortment of potential applications.
