Introduction

A Smart Parking System is an automated system that helps drivers locate free parking spaces in real-time using sensors and IoT technology. This project is widely used in shopping malls, offices, airports, and smart cities.

It minimizes parking time, reduces traffic congestion, and enhances urban mobility.

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Objective of the Project

• To detect available parking spaces using sensors.
• To display parking status digitally for easy navigation.
• To integrate with IoT platforms for real-time monitoring.
• To reduce traffic congestion caused by drivers searching for parking.

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Working Principle

The Smart Parking System works using IR or ultrasonic sensors to detect the presence of vehicles:

Step-by-Step Working

1. Each parking slot is equipped with a sensor to detect vehicle presence.
2. Sensors send signals to Arduino when a slot is occupied or empty.
3. Arduino updates the status and sends it to a display board or IoT platform.
4. Users can see real-time parking availability on a screen or mobile app.

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Components Required

• Arduino Uno or ESP8266/ESP32
• Ultrasonic Sensors (HC-SR04) or IR Sensors
• 16×2 LCD Display or LED indicators
• Buzzer (optional for alerts)
• Jumper Wires
• Breadboard / PCB
• Wi-Fi Module (ESP8266 for Arduino Uno)
• 5V Power Supply

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Circuit Diagram

Connections (for 3 Parking Slots using Ultrasonic Sensors)

Sensor 1:
Trig -> D2
Echo -> D3

Sensor 2:
Trig -> D4
Echo -> D5

Sensor 3:
Trig -> D6
Echo -> D7

LCD 16x2:
RS  -> D8
EN  -> D9
D4  -> D10
D5  -> D11
D6  -> D12
D7  -> D13
VCC -> 5V
GND -> GND
VO  -> Potentiometer middle pin

Optional: If using ESP8266, sensors connect to digital pins, and data is sent to IoT platforms like ThingSpeak or Blynk.

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Arduino Code for Smart Parking System

#include <LiquidCrystal.h>

#define TRIG1 2
#define ECHO1 3
#define TRIG2 4
#define ECHO2 5
#define TRIG3 6
#define ECHO3 7

LiquidCrystal lcd(8, 9, 10, 11, 12, 13);

long duration1, distance1;
long duration2, distance2;
long duration3, distance3;

void setup() {
  lcd.begin(16,2);
  Serial.begin(9600);

  pinMode(TRIG1, OUTPUT);
  pinMode(ECHO1, INPUT);
  pinMode(TRIG2, OUTPUT);
  pinMode(ECHO2, INPUT);
  pinMode(TRIG3, OUTPUT);
  pinMode(ECHO3, INPUT);
}

long getDistance(int trig, int echo) {
  digitalWrite(trig, LOW);
  delayMicroseconds(2);
  digitalWrite(trig, HIGH);
  delayMicroseconds(10);
  digitalWrite(trig, LOW);
  return pulseIn(echo, HIGH) * 0.034 / 2; // Distance in cm
}

void loop() {
  distance1 = getDistance(TRIG1, ECHO1);
  distance2 = getDistance(TRIG2, ECHO2);
  distance3 = getDistance(TRIG3, ECHO3);

  lcd.setCursor(0,0);
  lcd.print("S1:");
  lcd.print(distance1 < 10 ? "Occupied" : "Free");
  lcd.setCursor(0,1);
  lcd.print("S2:");
  lcd.print(distance2 < 10 ? "Occupied" : "Free");
  lcd.setCursor(8,1);
  lcd.print("S3:");
  lcd.print(distance3 < 10 ? "Occupied" : "Free");

  delay(500);
}

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Code Explanation

• Ultrasonic sensors detect distance to check if a vehicle is present.
• Threshold distance (<10 cm) determines if the slot is occupied.
• LCD displays the status of each parking slot in real-time.
• System can be expanded for multiple slots or integrated with IoT.

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Advantages

• Reduces time spent finding a parking slot
• Minimizes traffic congestion
• Real-time monitoring of parking slots
• Can be integrated with IoT for remote access

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Applications

• Shopping malls, airports, and offices
• Smart city infrastructure
• Public parking management systems
• IoT-based automated parking solutions

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Future Enhancements

• Add IoT cloud monitoring for mobile app display
• Use sensors with LEDs or traffic lights for slot guidance
• Integrate with payment systems for automated billing
• Add AI for vehicle recognition and slot allocation

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Conclusion

The Smart Parking System is a practical IoT project that improves urban mobility and convenience. It demonstrates real-time sensor monitoring, Arduino interfacing, and can be expanded for large-scale smart city applications.