Fraunhofer textile sensor
Flexible mechanical sensors that can be bonded or sewn into woven or knitted fabrics have been developed by German research lab Fraunhofer ISC.
Deformation, force and pressure can be measured, and strains up to 100% (doubling length) can be endured.
It is an elastomer film with flexible electrodes on both sides. Electrode patterning can be used to create an array of sensors. Silicone rubber is the preferred elastomer, with chemical cross-linking allowing hardness to be tuned.
“The textile-integrated sensors are washable, show a high wearing comfort and are reasonable in price,” said the lab. “They are applicable in medical devices, for preventing bed sores or for localising the pressure distribution in shoes, for example. They can also support personal training by measuring the posture via the clothes, or as an input device for game and fitness device controlling.”
In a technology demonstration aimed at diabetics (see photo), 40 capacitive dielectric elastomer sensors have been attached to the sole, heel, and ankle of a sock to measure 3D compression distribution around a foot.
An asic collects measurement data from the sensors and transmits it wirelessly to a phone or tablet, for example to tell a patient to change position or weight distribution.
Fraunhofer ISC is the Institute for Silicate Research in Würzburg, which focuses mainly on energy, environment and health. It will be showing its technology at the IDTechEX in Santa Clara.