The apply of electric paint(take paper bend sensor as an example)

These days, I found a very interesting material: the electric paint. To be more specific,this Paint is one kind of water-based paint but that it’s electrically conductive, which means that you can actually paint wires onto things like models, clothes, furniture, walls and so on.

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Due to people can use this paint to replace ordinary wires, so there are many creative products appear. For instance, by combining conductive ink and paper creases, Alice Rzezonka made her first paper bend sensor. Specifically, placing creases on top of a line of conductive ink folding the paper changes the resistance of electricity flowing through the ink.

Materials:Japanese Spatula, electric paint, paper or cardboard (around 250g/m²), masking tape, bone folder, clear spray paint, ruler, resistors 10k Ohm, arduino board,  jump wires, alligatorclips,  breadboard.

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Make:

1) To make the stripe of conductive ink cover the parts of the paper that you don’t want to paint with masking tape. There is special masking tape for paper, if you don’t have that stick the tape on and off a clean surface until it is not too sticky anymore and won’t damage the paper.

step1

2) Now use the spatula to spread the paint evenly. Take the masking tape off while the paint is still wet, this will get you clean etches.

3)Once it is dry cover everything with clear spray paint to seal the conductive ink and prevent it from smudging.

step2

4) With the help of the ruler and the bone folder create creases on top of the painted stripe. With the layout of the creases you actually determine how the resistance along the stripe will change when bended. Creating multiple creases will lead to a wider range of resistance change and react to folding different parts of the stripe. How strong you fold the paper along the creases also makes a strong difference. At this point I recommend experimenting with the different parameters until you get a feeling for it.

 

Connect:

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Code:

/*
based on the AnalogReadSerial example
Reads an analog input on pin 0, prints the result to the serial monitor.
add averaging of the values:
Define the number of samples to keep track of.  The higher the number,
the more the readings will be smoothed, but the slower the output will
respond to the input.
*/
int inputPin = A0;
int sensorValue = 0;        // value read from inputPin

const int numReadings = 25;
int readings[numReadings];      // the readings from the analog input
int index = 0;                  // the index of the current reading
int total = 0;                  // the running total
int average = 0;                // the average

// the setup routine runs once when you press reset:
void setup() {
// initialize serial communication at 9600 bits per second:
Serial.begin(9600);
}

// the loop routine runs over and over again forever:
void loop() {
/*____ read & smooth values ____*/
// subtract the last reading:
total= total – readings[index];
// read from the sensor:
readings[index] = analogRead(inputPin);
// add the reading to the total:
total= total + readings[index];
// advance to the next position in the array:
index = index + 1;

// if we’re at the end of the array…
if (index >= numReadings)
// …wrap around to the beginning:
index = 0;

// calculate the average:
average = total / numReadings;
// send it to the computer as ASCII digits
// read the analog in value:
sensorValue = average;
// print out the value you read:
Serial.println(sensorValue);
delay(1);        // delay in between reads for stability
}                                        (from:http://softcircuits.agustinaandreoletti.com/samples/extra-samples/paper-bend-sensor/)

Outcome:

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What inspired me:

This kind of paint may can help me expand the type of my sensors in Music Garden.Not only by pass the pots/flowers,but also by touch/bend or even more ways.

 

Reference:

http://softcircuits.agustinaandreoletti.com/samples/extra-samples/paper-bend-sensor/

http://www.bareconductive.com/make/tutorial-1/