Arduino Distance Meter (Ultrasonic + LED/Buzzer) দূরত্ব মাপার প্রজেক্ট! TechnicalWayej.Blogspot.Com

Function: সামনে 10cm-এর মধ্যে বাধা এলে LED/Buzzer অন হবে।

Required Components

Arduino UNO – 1

HC-SR04 Ultrasonic Sensor – 1

Buzzer (Active) – 1

LED – 1

220Ω resistor – 1

Jumper wires

🟦 Circuit Connections

Ultrasonic Sensor (HC-SR04) → Arduino

HC-SR04 Pin Arduino Pin

VCC 5V

GND GND

TRIG 9

ECHO 10

LED Connection

LED Pin Arduino

+ (Anode) D3 (through 220Ω resistor)

– (Cathode) GND

Buzzer Connection

Buzzer Pin Arduino

+ D4

– GND

🧠 How it Works

Arduino TRIG pin থেকে একটি short pulse পাঠাবে

সামনে কোনো বাধা থাকলে ECHO pin-এ ফিরে আসবে

Arduino সময় মেপে distance বের করবে

Distance কম হলে LED/Buzzer চালু হবে

// ✅ #define TRIG 9
#define ECHO 10
#define LED 3
#define BUZZER 4

void setup() {
  pinMode(TRIG, OUTPUT);
  pinMode(ECHO, INPUT);
  pinMode(LED, OUTPUT);
  pinMode(BUZZER, OUTPUT);
  Serial.begin(9600);
}

void loop() {
  digitalWrite(TRIG, LOW);
  delayMicroseconds(2);

  digitalWrite(TRIG, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG, LOW);

  long duration = pulseIn(ECHO, HIGH);
  int distance = duration * 0.034 / 2;

  Serial.print("Distance: ");
  Serial.print(distance);
  Serial.println(" cm");

  if (distance <= 10) {
    digitalWrite(LED, HIGH);
    digitalWrite(BUZZER, HIGH);
  } else {
    digitalWrite(LED, LOW);
    digitalWrite(BUZZER, LOW);
  }

  delay(200);
}

int led = 13;

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

void loop() {
  digitalWrite(led, HIGH);
  delay(1000);
  digitalWrite(led, LOW);
  delay(1000);
}
  

Circuit diagram