Control a Robotic Arm via Wi-Fi

Difficulty Level: Intermediate

This tutorial guides you through controlling a robotic arm using an ESP32 microcontroller via Wi-Fi. You will create a web interface that sends commands to the robotic arm's servos.

Components Required

• ESP32 Development Board
• Robotic Arm Kit (with servos)
• Jumper Wires
• Power Supply for Servos
• Computer with Arduino IDE
• Wi-Fi Network

Wiring the Robotic Arm

Connect the servos of the robotic arm to the ESP32 as follows:

• Connect the control wire of each servo to a GPIO pin on the ESP32 (e.g., GPIO 13, 12, 14).
• Connect the power and ground wires of the servos to an appropriate power supply.

Arduino IDE Setup

1. Open the Arduino IDE and ensure you have the ESP32 board definitions installed.

2. Load the following code onto your ESP32:

#include 
#include 
#include 

const char* ssid = "YOUR_SSID";        // Replace with your Wi-Fi SSID
const char* password = "YOUR_PASSWORD"; // Replace with your Wi-Fi Password

WebServer server(80);
Servo servo1;  // Define servo objects
Servo servo2;
Servo servo3;

void setup() {
    Serial.begin(115200);
    servo1.attach(13); // Attach servo1 to GPIO 13
    servo2.attach(12); // Attach servo2 to GPIO 12
    servo3.attach(14); // Attach servo3 to GPIO 14

    // Connect to Wi-Fi
    WiFi.begin(ssid, password);
    while (WiFi.status() != WL_CONNECTED) {
        delay(1000);
        Serial.println("Connecting to WiFi...");
    }
    Serial.println("Connected to WiFi");

    // Setup routes for the web server
    server.on("/", handleRoot);
    server.on("/move", handleMove);
    server.begin();
}

void loop() {
    server.handleClient();
}

void handleRoot() {
    server.send(200, "text/html", 
    "
Robotic Arm Control
"
    "Move Servo 1 to 90°"
    "Move Servo 1 to 0°"
    "Move Servo 2 to 90°"
    "Move Servo 2 to 0°"
    "Move Servo 3 to 90°"
    "Move Servo 3 to 0°"
    );
}

void handleMove() {
    if (server.hasArg("servo") && server.hasArg("angle")) {
        int servo = server.arg("servo").toInt();
        int angle = server.arg("angle").toInt();

        // Move the servo to the specified angle
        switch (servo) {
            case 1:
                servo1.write(angle);
                break;
            case 2:
                servo2.write(angle);
                break;
            case 3:
                servo3.write(angle);
                break;
        }
        server.send(200, "text/html", "Servo moved!");
    } else {
        server.send(400, "text/html", "Invalid request");
    }
}
        

Uploading the Code

1. Select the appropriate board and port in the Arduino IDE.

2. Click on the upload button to upload the code to the ESP32.

Testing the Setup

1. Open the Serial Monitor to view the ESP32's IP address once it's connected to Wi-Fi.

2. Open a web browser and enter the ESP32's IP address.

3. You should see the control buttons for the robotic arm.

Conclusion

You have successfully set up a Wi-Fi-controlled robotic arm using an ESP32. You can expand this project by adding more servos or implementing more complex control mechanisms.