Proximity sensor using Capacitance
As is suggested by the name, the sensor is looking for a change in capacitance in the three-dimensional field around the pad of ink.
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Learn how to make a simple capacitance sensor using a pad of Electric Paint, an Arduino and a resistor.
To begin you will need:
The sensor explained below is known as a capacitance sensor. As is suggested by the name, the sensor is looking for a change in capacitance in the three-dimensional field around the pad of ink. The device consists of a pad of ink acting as the sensing surface and small circuit containing a resistor and a simple microprocessor. By manipulating the size of the pad of ink and the resistor, we can change the sensor’s sensitivity and effective sensing distance. We have demonstrated reliable sensing of a person’s hand from up to 60 cm and are confident that we could sense at much greater distances with appropriate circuit design.
The capacitance sensor application is potentially quite significant for Bare Conductive for three reasons. First, the ink is a versatile material and can be used anywhere that paint can be applied. Second, as the ink is non-toxic, our ink can be applied in places that would be inappropriate with other conductive inks. Third, in comparison to other conductive inks, our product is dramatically less expensive, thus expanding its scope of potential uses.