Motion Detection with Digital Infrared Motion Sensor (PIR)

The usefulness of this sensor allows you to detect motion. They often refer to this as a PIR sensor, "Passive Infrared", "pyroelectric", or "IR motion" sensor. / (Digital infrared motion sensors)

PIR is basically made ​​of a pyroelectric sensor (which you can see above as the round metal can with a rectangular crystal in the middle), which can detect infrared radiation levels. Everything emits some low-level radiation, and panas.Jika more radiation is emitted. Sensor detector will see the size of the IR than the other, and the output will swing high or low


SPECIFICATION:

     Type: Digital
     Supply Voltage :3-5V
     Current: 50μA
     Working temperature: 0 ℃ -70 ℃
     Output level (HIGH): 4V
     Output level (LOW): 0.4V
     Detect angle: 110 Degree
     Detect distance: 7 meters
     Size: 28mm × 36mm
     Weight: 25g

PIR sensor reading

PIR sensor connects to the microcontroller is really simple. PIR acts as a digital output so that all you need to do is use a pin to flip high (detected) or low (undetectable).

Power PIR to 5V and ground is connected to ground. Then connect the output to a digital pin. In this example we will use the pin 2.

The code is very simple, and basically just keep track of whether the input to pin 2 is high or low. So that it prints a message when the movement has been started and stopped.

/* * PIR sensor tester */   int ledPin = 13; // choose the pin for the LED int inputPin = 2; // choose the input pin (for PIR sensor) int pirState = LOW; // we start, assuming no motion detected int val = 0; // variable for reading the pin status   void setup() { pinMode(ledPin, OUTPUT); // declare LED as output pinMode(inputPin, INPUT); // declare sensor as input   Serial.begin(9600); }   void loop(){ val = digitalRead(inputPin); // read input value if (val == HIGH) { // check if the input is HIGH digitalWrite(ledPin, HIGH); // turn LED ON if (pirState == LOW) { // we have just turned on Serial.println("Motion detected!"); // We only want to print on the output change, not state pirState = HIGH; } } else { digitalWrite(ledPin, LOW); // turn LED OFF if (pirState == HIGH){ // we have just turned of Serial.println("Motion ended!"); // We only want to print on the output change, not state pirState = LOW; } } }