So I’ve spent, I dunno, about 8 cumulative hours trying to get three QProx QT113 capacitive sensors to work as proximity sensors. These are sensors that detect the capacitance of a human touch and return a binary value to indicate said touch. (It’s exactly the same tech as the iPod touch wheel.) They supposedly can be “tuned”, however, to read the capacitance of human presence within a few centimeters. I need about 8cm or so. That way when someone walks up to the box and leans in, it can sense their presence and cycle the pattern that is displayed, as well as to detect the presence of a user’s hands near the sides of the box. Currently, it reads about a distance of about 2cm. It’s not bad, as there are plenty of people who seem to enjoy the box’s visuals so much that they want to climb inside, but it doesn’t switch for everybody. I’ve tried nearly everything that the datasheet recommends…from increasing the capacitance at the sensor pins via parallel capacitors, to altering the material and size of the electrode. Nothing seems to help. It’s driving me nuts!
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