🧠Smart Dustbin (WiFi – Home Router Mode)

🎯 Objective of This Lesson

Students will learn:

• How ESP32 connects to Home WiFi

• What is Station Mode (STA Mode)

• How client-server communication works over router

• How to monitor dustbin from any device connected to same WiFi

🌐 How This Version Works

1. ESP32 connects to your Home WiFi

2. Router assigns IP address

3. Mobile/PC connects to same WiFi

4. Open WiFi Serial Terminal

5. Enter ESP32 IP address

6. Monitor dustbin wirelessly

Now no direct hotspot required.

🔌 Hardware Connections (Same as Previous Lessons)

Ultrasonic 1 – Hand Detection

• TRIG → GPIO 5

• ECHO → GPIO 18

Ultrasonic 2 – Garbage Level

• TRIG → GPIO 17

• ECHO → GPIO 16

Servo

• Signal → GPIO 13

🧾 Complete ESP32 Code (Home Router Mode – Copy & Paste)

#include <WiFi.h>
#include <ESP32Servo.h>

// -------- WiFi Credentials --------
const char* ssid = "YOUR_WIFI_NAME";
const char* password = "YOUR_WIFI_PASSWORD";

WiFiServer server(80);

// -------- Pin Definitions --------
#define TRIG1 5
#define ECHO1 18

#define TRIG2 17
#define ECHO2 16

#define SERVO_PIN 13

Servo myServo;

long duration;
float distanceHand;
float distanceGarbage;

// -------- Setup --------
void setup() {

Serial.begin(115200);

WiFi.begin(ssid, password);
Serial.println("Connecting to WiFi...");

while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.print(".");
}

Serial.println("\nConnected to WiFi");
Serial.print("ESP32 IP Address: ");
Serial.println(WiFi.localIP());

server.begin();

pinMode(TRIG1, OUTPUT);
pinMode(ECHO1, INPUT);

pinMode(TRIG2, OUTPUT);
pinMode(ECHO2, INPUT);

myServo.attach(SERVO_PIN);
myServo.write(0); // Lid closed
}

// -------- Distance Function --------
float getDistance(int trigPin, int echoPin) {

digitalWrite(trigPin, LOW);
delayMicroseconds(2);

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

duration = pulseIn(echoPin, HIGH);

float distance = duration * 0.034 / 2;

return distance;
}

// -------- Main Loop --------
void loop() {

WiFiClient client = server.available();

if (client) {

distanceHand = getDistance(TRIG1, ECHO1);

if (distanceHand > 0 && distanceHand < 20) {
myServo.write(90);
delay(3000);
myServo.write(0);
client.println("Hand Detected - Lid Opened");
}

distanceGarbage = getDistance(TRIG2, ECHO2);

client.print("Garbage Distance: ");
client.print(distanceGarbage);
client.println(" cm");

if (distanceGarbage > 0 && distanceGarbage < 8) {
client.println("Status: Dustbin is FULL");
} else {
client.println("Status: Dustbin is NOT Full");
}

client.println("----------------------");

delay(1000);
}
}

🧠 Code Explanation (Step-by-Step)

1️⃣ WiFi Station Mode

This connects ESP32 to your home router.

This mode is called:

👉 STA (Station Mode)

ESP32 behaves like a mobile phone connecting to WiFi.

2️⃣ Checking Connection

This waits until WiFi is connected.

Once connected:

This shows the IP address assigned by router.

Example:

3️⃣ Starting Server

Creates a TCP server on port 80.

4️⃣ Client Connection

If any mobile or PC connects → client becomes active.

Data is sent using:

5️⃣ Hand Detection Logic

If distance < 20 cm:

• Servo rotates to 90°

• Lid opens

• Closes after 3 seconds

• Message sent to WiFi client

6️⃣ Garbage Detection Logic

If garbage distance < 8 cm:

Else:

📱 How To Connect (Home Router Mode)

Step 1 – Replace WiFi name and password in code
Step 2 – Upload code
Step 3 – Open Serial Monitor
Step 4 – Note IP address (example 192.168.1.105)
Step 5 – Connect mobile to same WiFi
Step 6 – Open WiFi Serial Terminal app
Step 7 – Enter:

IP → 192.168.1.105
Port → 80

Step 8 – Connect

Now you can monitor dustbin.

🔎 Difference: Hotspot vs Router Mode

🎓 Learning Outcomes

We now understand:

• Station Mode (STA)

• Router-based communication

• IP addressing

• TCP server concept

• Real IoT networking basics