Week 4

Sensor was chosen in my project is Piezoelectric sensor.
This sensor was chosen because the ability to detect vibration and accurate.

Here some basic information piezoelectric sensor :

A piezoelectric sensor is a device that uses the piezoelectric effect to measure pressure, acceleration, strain or force by converting them to an electrical charge.

Here some arduino 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. It writes
 * "knock" to the serial port if the Threshold is crossed,
 * and toggles the LED on pin 13.
 *
 * (cleft) 2005 D. Cuartielles for K3
 */

int ledPin = 13;
int knockSensor = 0;               
byte val = 0;
int statePin = LOW;
int THRESHOLD = 100;

void setup() {
 pinMode(ledPin, OUTPUT); 
 beginSerial(9600);
}

void loop() {
  val = analogRead(knockSensor);     
  if (val >= THRESHOLD) {
    statePin = !statePin;
    digitalWrite(ledPin, statePin);
    printString("Knock!");
    printByte(10);
    printByte(13);
  }
  delay(100);  // we have to make a delay to avoid overloading the serial port
}

This arduino code was tested and the output was monitored by using Serial Monitor.

Yes, the piezoelectric sensor function well as expected. So, the next is modified the coding to become a counter. The idea is, when a person step on the sensor, the sensor detect and count as a step.