Living Architecture Fall 2009 Pratt

Description:
We had a mini-breakthrough and got the piezo tab to trigger a response in an LED.
One 'flick' of the tab turns the LED on, and another 'flick' turns it off, and so on.

Input:
Piezo Film Sensor

Output:
LED turning ON and OFF

Setup:





















Result:



Code:

/* Knock Sensor
* ----------------
*
* Program using a Piezo element as if it was a knock sensor.
*
* We have to basically listen to an analog pin and detect
* if the signal goes over a certain threshold. If the Threshold
* is crossed, and toggles the LED on pin 13.
*
* Modified from one by (cleft) 2005 D. Cuartielles for K3
*/

int ledPin = 13;
int knockSensor = 2;           
byte val = 0;
int statePin = LOW;
int THRESHOLD = 100;  // if it's too sensitive then change this value

void setup()
{
pinMode(ledPin, OUTPUT);
}

void loop()
{
val = analogRead(knockSensor); 
if (val >= THRESHOLD) {        // check the piezo
statePin = !statePin;       // sets the pin to the opposite state
digitalWrite(ledPin, statePin); // turn on or off the LED
}
}


http://electronics.divinechildhighschool.org/Home/Arduino-Lessons/analog-read-and-a-piezo