This is a very simple touch sensor switch that is build with the 555 timer IC. You just need to touch the metal plate and the relay gets energised and is kept in this state for about 100 seconds, then ...

The touch sensor can be constructed using a small piece of a printed circuit board ( two small tracks with a 2 mm distance between each other ) . This circuit is powered using a 12 volts DC power ...

21 thoughts on “ Simple Touch Sensor And Other Lessons ” ril3y says: February 3, 2011 at 7:51 ... you need to redo the circuit upside down with pnp transistors, or add an inverter ...

Watchdog Timer Enables Capacitive Touch Sensor Sept. 24, 2009 A simple four-component circuit allows a single I/O line from any microcontroller to sense the states of two capacitive touch sensors.

So far the circuit layout of a multi-touch sensor has been similar to graph paper. The wires run horizontally, vertically, and parallel to each other.

Capacitive touch sensing allows for triggering the sensor without actually physically touching one’s lips to the electrodes, which [Nathan] did by putting a clear plastic layer over the PCB traces.

To achieve this invisibility the touch sensor circuit lines must be printed in sizes smaller than 5 microns. To give you a comparative example a human hair is 40 to 120 microns wide.

A sensor that can accurately recognize and distinguish objects up to 10 centimeters – about four inches – away without needing to touch them physically has been developed. It could provide a ...