Some of you might know Velostat. The electrically conductive packaging plastic for circuits and computer components. Nowadays it’s often used as a sensor material. When you connect two leads from the plastic to an analogue port of a microcontroller, you can sense if there is pressure on the material. We’ve been trying different ways of sensing with Velostat: using tiny pieces for the sensing of small touches to big tiles of Velostat for the sensing of bigger weights. See the differences in Ohm’s when there is weight on the tile.
In the first two pictures, there are two layers of Velostat. By applying pressure the two pieces make more contact and the Ohm count drops. The difference was so tiny that we needed to test with different materials. The last two foto’s show the difference in Ohm’s with one sheet of Velostat and a strip of conductive tape on the other side. Eventually we tried an isolating sheet in between, but then the sheets didn’t connect and there often was no reading at all. More testing tomorrow!