Building a Capacitive Proximity Sensor using Bare Paint

In this tutorial, we are going to make a simple capacitance sensor using a pad of Bare Paint, an Arduino and a resistor. When correctly constructed, this sensor can detect the presence of a person from up to 300 mm and can work behind any non-conductive material (glass, wood, plastic, etc).

Please watch this VIDEO for a live explanation.

By the end of the tutorial you'll have a pad of Paint connected to the Arduino, sending a stream of numbers to your computer's serial port. In later tutorials we'll take a look at what you can do with these numbers. This tutorial is based on the CapSense library and code that can be found here:http://www.arduino.cc/playground/Main/CapSense. All credit for the code goes to Paul Badger for making this so easy to implement!

Materials

Bare Paint
Paint Brush
Paper
Arduino
USB Cable
Bread Board
Jump Wires
Resistors
Aligator Clip
Paper Clip


Components

Arduino: Sparkfun
Breadboard: Sparkfun
Jump Wires: Sparkfun
USB Cable: Sparkfun
Resistors: Sparkfun

Step 1 Materials

The first step is to gather the appropriate materials, listed above
To make a capacitance sensor using Bare Paint, you'll need:

1. A jar of Bare Paint

2. Small selection of resistors, between 100k ohm and 20M ohm (specific size is not important)

3. An Arduino, preferably Uno, Duemillonove or equivalent

4. Solderless breadboard and some jump wires

5. Some general prototyping materials to connect the pad of Paint to the Arduino, like wire, alligator clips etc

6. USB cable to connect the Arduino to you computer

Comments

[Computothought]

Can see a zillion uses for this. What paintings at an art gallery are most looked at most? What areas of a building are most used? etc. etc. After looking at the code, may try to make a pc parallel port version. Have wriiten pwm routines before with leds, just a matter of seeing what works.