PIR Sensor Detecting Object Using Arduino

Introduction

Figure1: PIR Sensor

• It is used to detect the human being moving around approximately 10m from sensor.
• The actual range is between 5m to 12m.
• It is of high sensitivity and low noise.

Parts Of List

• Arduino Board
• PIR Sensor
• Buzzer
• Bread Board
• LED
• Hookup wire

Connection To An Arduino Board

• In the PIR sensor they have three pins.
• The first pin can be connected to dc voltage range as 5v.
• The second pin can be connected to the Arduino board 5 in digital pin.

LED

• The anode(+) pin can be connected to the digital pin 7 to an Arduino board.
• The cathode(-) pin can be connected to the Gnd to an Arduino board.

Buzzer

Figure 2: Buzzer

Connection

• The red color wire can be connected to the digital pin 10 to the Arduino board.
• The black color wire can be connected to the Gnd to the Arduino board.
• We can connect both the wires in exchange.

Programming

int ledPin = 7; // choose the pin for the LED
int inputPin = 5; // 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
int pinSpeaker = 10; //Set up a speaker on a PWM pin (digital 9, 10, or 11)
void setup()
{
    pinMode(ledPin, OUTPUT); // declare LED as output
    pinMode(inputPin, INPUT); // declare sensor as input
    pinMode(pinSpeaker, OUTPUT);
    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
        playTone(300, 160);
        delay(150);
        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
        playTone(0, 0);
        delay(300);

        if (pirState == HIGH)
        {
            // we have just turned off
            Serial.println("Motion ended!");
            // We only want to print on the output change, not state
            pirState = LOW;
        }
    }
}
// duration in mSecs, frequency in hertz
void playTone(long duration, int freq)
{
    duration *= 1000;
    int period = (1.0 / freq) * 1000000;
    long elapsed_time = 0;
    while (elapsed_time < duration)
    {
        digitalWrite(pinSpeaker, HIGH);
        delayMicroseconds(period / 2);
        digitalWrite(pinSpeaker, LOW);
        delayMicroseconds(period / 2);
        elapsed_time += (period);
    }
}

Explanation

• In this concept the PIR sensor can act as the night security alarm at a particular distance. For example, we kept things on the table. If anybody touches them then there is an alert that produce sound.

Programming Explanation

• Play tone means the value of the buzzer when it produced the sound.
• If the Led is on the buzzer produced the sound and they mention the value.
• If the Led is off the buzzer can't produce the sound then they could not mention the value.

Application

• All outdoor lights
• Lift Lobby
• Multi Apartment Complexes
• Common staircases
• For Basement or Covered Parking Area
• Shopping Malls
• For garden lights

Output

                                                Figure 3: Output

 

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