Movement Detector Using The PIR Sensor

100

Article

Introduction

In this article I'll show you how to use and work with a PIR sensor and to sense whether movement is detected or NOT.

Requirements

To build this project you need the following:

Arduino
PIR Sensor
Bread Board
led
Jumper Wires

Figure: PIR Sensor

Connection

PIR Sensor to Digital Pin 8
Vcc to 5c
Gnd to Gnd

Led

Anode Pin to the digital Pin13
Cathode pin to the Gnd

Programming

int PIR=8;
int led=13;
int minsec=60;
long last= -minsec*1000;
void setup()
{
pinMode(PIR,INPUT);
pinMode(led,OUTPUT);
Serial.begin(9600);
}
void loop()
{
long now=millis();
if(digitalRead(PIR)==HIGH)
{
if(now > (last+ minsec*1000))
{
digitalWrite(led,HIGH);
Serial.println("Movement Occured");
last=now;
}
else {
Serial.println("Not Occured");
}
delay(500);
}
}

Explanation

First we want to initialize the value to the PIR sensor and led. Set the minimum sec value as 60 seconds. In the setup function we want to set the PIR sensor as INPUT and led as OUTPUT. Set the baud rate as 9600 for data transfer between Arduino and PC in the loop function we want to set the condition for PIR.

if(digitalRead(PIR)==HIGH)
{
if(now > (last+ minsec*1000))
{
digitalWrite(led,HIGH); //Led On
Serial.println("Movement Occured");
last=now;
}

If any movement occured ,the PIR sensor value is HIGH and the led is turned ON, else it is in the off condition and prints the value in the serial monitor as movement occurred

Output

Figure: Movement Detector