Piano en hoja de papel - Arduino / Fritzing

Con esta configuración se puede tocar un piano en hoja de papel, con ayuda del granito de un lápiz que funciona como conductor.

Partes

Arduino Uno
Protoboard
7 resistencias 1 Mega ohm
7 clips
1 hoja papel
lápiz

Fritzing

Código

/* DIY Piano

   - DIY Piano with Arduino. This is a very simple project.

   - ONLY needed some very cheap materials,

     e.g. pencil, A4 paper, paper clip, speaker, male-to-male jumper, breadboard and Arduino Uno board.

   - Of course the Arduino Uno board is not cheap, but it is reusable for other projects too. So it is worth to own one.

   - This project using the concept of capasitive sensor, so no switch/button is required for it.

   - Here is the link of capacitive sensor. For better understanding, please visit the page.

     http://playground.arduino.cc//Main/CapacitiveSensor?from=Main.CapSense

   - To watch the Demo of This Project:

     http://www.youtube.com/watch?v=X4QNT5hOHLs&list=TLlm-tAV1gEzDF4VV39VdjCSLNlfe0tTpU

   Created by:

   Oh Hai Seng || Junny Oh    07 November 2013

*/

// Import the CapacitiveSensor Library.

#include <CapacitiveSensor.h>

// Name the pin as led.

#define speaker 11

// Set the Send Pin & Receive Pin.

CapacitiveSensor   cs_2_3 = CapacitiveSensor(2,3);        /* 10M resistor between pins 4 & 2, pin 2 is sensor pin, add a wire and or foil if desired*/

CapacitiveSensor   cs_2_4 = CapacitiveSensor(2,4);        /* 10M resistor between pins 4 & 6, pin 6 is sensor pin, add a wire and or foil*/

CapacitiveSensor   cs_2_5 = CapacitiveSensor(2,5);        /* 10M resistor between pins 4 & 8, pin 8 is sensor pin, add a wire and or foil*/

CapacitiveSensor   cs_2_6 = CapacitiveSensor(2,6);        /* 10M resistor between pins 4 & 8, pin 8 is sensor pin, add a wire and or foil*/

CapacitiveSensor   cs_2_7 = CapacitiveSensor(2,7);        /* 10M resistor between pins 4 & 8, pin 8 is sensor pin, add a wire and or foil*/

CapacitiveSensor   cs_2_8 = CapacitiveSensor(2,8);        /* 10M resistor between pins 4 & 8, pin 8 is sensor pin, add a wire and or foil*/

CapacitiveSensor   cs_2_9 = CapacitiveSensor(2,9);        /* 10M resistor between pins 4 & 8, pin 8 is sensor pin, add a wire and or foil*/

void setup()

{

  cs_2_3.set_CS_AutocaL_Millis(0xFFFFFFFF);     // turn off autocalibrate on channel 1 - just as an example

  // Arduino start communicate with computer.

  Serial.begin(9600);

}

void loop()

{

  // Set a timer.

  long start = millis();

  // Set the sensitivity of the sensors.

  long total1 =  cs_2_3.capacitiveSensor(30);

  long total2 =  cs_2_4.capacitiveSensor(30);

  long total3 =  cs_2_5.capacitiveSensor(30);

  long total4 =  cs_2_6.capacitiveSensor(30);

  long total5 =  cs_2_7.capacitiveSensor(30);

  long total6 =  cs_2_8.capacitiveSensor(30);

  long total7 =  cs_2_9.capacitiveSensor(30);

  Serial.print(millis() - start);        // check on performance in milliseconds

  Serial.print("\t");                    // tab character for debug windown spacing

  Serial.print(total1);                  // print sensor output 1

  Serial.print("\t");                    // Leave some space before print the next output

  Serial.print(total2);                  // print sensor output 2

  Serial.print("\t");                    // Leave some space before print the next output

  Serial.print(total3);                  // print sensor output 3

  Serial.print("\t");                    // Leave some space before print the next output

  Serial.print(total4);                  // print sensor output 4

  Serial.print("\t");                    // Leave some space before print the next output

  Serial.print(total5);                  // print sensor output 5

  Serial.print("\t");                    // Leave some space before print the next output

  Serial.print(total6);                  // print sensor output 6

  Serial.print("\t");                    // Leave some space before print the next output

  Serial.println(total7);                // print sensor output 7

                                         // "println" - "ln" represent as "line", system will jump to next line after print the output.

  // When hand is touched the sensor, the speaker will produce a tone.

  // I set a threshold for it, so that the sensor won't be too sensitive.

  if (total1 > 150) tone(speaker,523);

  if (total2 > 150) tone(speaker,587);

  if (total3 > 150) tone(speaker,659);

  if (total4 > 150) tone(speaker,698);

  if (total5 > 150) tone(speaker,783);

  if (total6 > 150) tone(speaker,880);

  if (total7 > 150) tone(speaker,988);

  // When hand didn't touch on it, no tone is produced.

  if (total1<=150  &  total2<=150  &  total3<=150 & total4<=150  &  total5<=150  &  total6<=150 &  total7<=150)

    noTone(speaker);

  delay(10);                             // arbitrary delay to limit data to serial port

}

Nota: antes de compilar el contenido debe instalarse la siguiente librería. 

• Programa 
• Librerias
• Instalar desde zip

Nota: se puede comprobar el funcionamiento en el monitor serie de Arduino IDE