Night Watchman (Raat Ka Chowkidar) Robotic Kit

Icon Concept (For Designer)

Raat ka scene (Chand nikla hai). Ek Chor (Thief) dabe paon aa raha hai aur achanak 3 Tez Lights (Red/Green/Yellow) uske chehre par padti hain. Chor ghabra gaya hai.

What It Does (Yeh Kya Karta Hai?)

Yeh system din mein “OFF” rehta hai (bijli bachata hai). Jaise hi Raat (Andhera) hoti hai, yeh active ho jata hai. Agar raat ke waqt koi iske qareeb guzarta hai, toh yeh foran 3 LEDs jala deta hai taake aane wala nazar aa jaye.

Components Required

• Microcontroller: Arduino Uno
• Ultrasonic Sensor (HC-SR04)
• LDR (Light Sensor)
• 3 LEDs (Koi bhi rang – Red, Yellow, Green)
• Jumper Wires & Breadboard

Wiring (Taarein Jorna)

Common GND: Breadboard ki Blue line ko Arduino GND se jod dein

1. Ultrasonic Sensor:

• VCC: → 5V
• GND: → GND
• Trig: → Pin 9
• Echo: → Pin 10

2. LDR (Bina Resistor):

• Ek taang → GND
• Doosri taang → A0

3. 3 LEDs (Alert Lights):

• LED 1 (+): → Pin 13
• LED 2 (+): → Pin 12
• LED 3 (+): → Pin 11
• Sabki Choti Taangein (-): GND line mein.

Code

// Project 13: Night Watchman (LED Version)
// PlzPapa Robotic Kit

#define TRIG_PIN 9
#define ECHO_PIN 10
#define LDR_PIN A0

// LEDs ke pins define karein
int led1 = 13;
int led2 = 12;
int led3 = 11;

// Settings
int distanceThreshold = 50; // 50cm ke andar detect karega
int darkThreshold = 800;    // Andhere ki value (High value = Dark)

void setup() {
  pinMode(TRIG_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);
  
  // LEDs setup
  pinMode(led1, OUTPUT);
  pinMode(led2, OUTPUT);
  pinMode(led3, OUTPUT);
  
  // LDR Internal Resistor ON
  pinMode(LDR_PIN, INPUT_PULLUP);
  
  Serial.begin(9600);
}

void loop() {
  // 1. Roshni check karo
  int lightValue = analogRead(LDR_PIN);
  
  // 2. Distance check karo
  long duration, distance;
  digitalWrite(TRIG_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);
  duration = pulseIn(ECHO_PIN, HIGH);
  distance = (duration / 2) / 29.1;
  
  // Debugging ke liye values dekhein
  Serial.print("Roshni: ");
  Serial.print(lightValue);
  Serial.print(" | Doori: ");
  Serial.println(distance);

  // --- LOGIC ---
  // Agar Andhera hai (> 800) ...
  if (lightValue > darkThreshold) {
    
    // ... AUR koi kareeb aa gaya (< 50cm)
    if (distance < distanceThreshold && distance > 0) {
      Serial.println("ALERT! Chor Aaya!");
      
      // Teeno LEDs Jalao (Spotlight ON)
      digitalWrite(led1, HIGH);
      digitalWrite(led2, HIGH);
      digitalWrite(led3, HIGH);
      
      delay(2000); // 2 Second tak jala kar rakho
    } 
    else {
      // Koi nahi hai, Lights Band rakho
      digitalWrite(led1, LOW);
      digitalWrite(led2, LOW);
      digitalWrite(led3, LOW);
    }
  } 
  else {
    // Agar Din hai (Roshni hai) -> Sab Band
    digitalWrite(led1, LOW);
    digitalWrite(led2, LOW);
    digitalWrite(led3, LOW);
  }
  
  delay(200);
}