Introduction

A Smart Dustbin is an automated waste management system that opens its lid automatically when it detects a person nearby. This project promotes hygiene by minimizing physical contact and is widely used in smart cities, hospitals, offices, and homes.

The Smart Dustbin uses sensors and a microcontroller to make waste disposal more convenient and hygienic.

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Objective of the Project

The main objectives of this project are:

• To reduce physical contact with dustbins.
• To promote cleanliness and hygiene.
• To automate waste disposal using sensors.
• To understand sensor and motor interfacing with Arduino.

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Working Principle

The Smart Dustbin works on the principle of distance measurement using an ultrasonic sensor.

Step-by-Step Working

1. The ultrasonic sensor continuously measures distance.
2. When a person comes close to the dustbin, the sensor detects the object.
3. Arduino processes the distance data.
4. If the distance is below a preset value, Arduino activates the servo motor.
5. The servo motor opens the dustbin lid.
6. After a few seconds, the lid closes automatically.

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Components Required

• Arduino Uno
• Ultrasonic Sensor (HC-SR04)
• Servo Motor (SG90)
• Jumper Wires
• Breadboard
• Power Supply (5V)
• Dustbin (for mounting the system)

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Circuit Diagram

Connections

Ultrasonic Sensor:
VCC  -> 5V (Arduino)
GND  -> GND
Trig -> D9
Echo -> D10

Servo Motor:
VCC  -> 5V
GND  -> GND
Signal -> D6

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Arduino Code for Smart Dustbin

#include <Servo.h>

Servo lidServo;

int trigPin = 9;
int echoPin = 10;
int servoPin = 6;

long duration;
int distance;

void setup() {
  lidServo.attach(servoPin);
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  lidServo.write(0); // Lid closed
}

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

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

  duration = pulseIn(echoPin, HIGH);
  distance = duration * 0.034 / 2;

  if (distance > 0 && distance < 20) {
    lidServo.write(90); // Open lid
    delay(3000);
    lidServo.write(0);  // Close lid
  }
  delay(500);
}

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Code Explanation

• Ultrasonic sensor measures distance.
• Arduino calculates distance in centimeters.
• If distance is less than 20 cm, servo motor rotates.
• Servo opens the lid and closes it after 3 seconds.

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Advantages

• Touch-free operation
• Hygienic and user-friendly
• Energy efficient
• Easy to implement

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Applications

• Smart homes
• Hospitals
• Offices
• Public places
• Smart city projects

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Future Enhancements

• Add garbage level detection
• IoT-based monitoring
• Mobile app alerts
• Solar power support

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Conclusion

The Smart Dustbin is an innovative and practical electronics project that encourages cleanliness and smart living. It demonstrates the use of sensors, microcontrollers, and automation in real-life applications and serves as a foundation for advanced smart city solutions.