Introduction

Servo motors are a type of actuator that can be controlled to rotate to a specific angle. They are widely used in robotics, automation, and hobby projects. In this blog post, we’ll explore how to control a servo motor using an ESP32 microcontroller.

What You’ll Need

• ESP32 microcontroller (e.g., ESP32-WROOM-32)
• Servo motor (e.g., SG90)
• Breadboard
• Jumper wires
• 5V power supply

Understanding Servo Motors

Servo motors have three wires:

• Power (V+): Connected to the positive terminal of the power supply.
• Ground (GND): Connected to the negative terminal of the power supply.
• Signal (PWM): Connected to a digital pin on the microcontroller.

Servo motors operate based on pulse-width modulation (PWM). The width of the pulse determines the angle to which the servo rotates. A pulse width of 1ms corresponds to 0 degrees, 2ms corresponds to 90 degrees, and 1.5ms corresponds to 180 degrees.

Connecting the Servo to ESP32

1. Connect the 5V power supply to the V+ pin of the servo.
2. Connect the ground of the power supply to the GND pin of the servo.
3. Connect the signal pin of the servo to a digital pin on the ESP32 (e.g., GPIO13).

ESP32 Code

Here’s a basic example of ESP32 code to control a servo motor:

C++

#include <ESP32Servo.h>

Servo myservo;  // create servo object to control a servo 

int servoPin = 25;  // GPIO pin connected to the servo signal

void setup() {
  
  myservo.attach(servoPin);  // attaches the servo on GPIO 18 to the servo object
  
  }
  
  void loop() {
    myservo.write(0);  // tell servo to go to position 0
    delay(1000);       // wait 1 second
   
    myservo.write(90); // tell servo to go to position 90
    delay(1000);       // wait 1 second  
   
    myservo.write(180);// tell servo to go to position 180  
    delay(1000);       // wait 1 second
    }

In this code:

• #include <Arduino.h> includes the Arduino core library.
• #define SERVO_PIN 13 defines the digital pin connected to the servo.
• servoWrite(SERVO_PIN, angle) function sets the servo angle to the specified value.

Uploading the Code

1. Connect your ESP32 to your computer using a USB cable.
2. Open the Arduino IDE and select the correct board and port.
3. Upload the code to the ESP32.

Testing the Servo

Once the code is uploaded, you should see the servo motor move between the 0, 90, and 180-degree positions. You can modify the delay times and angles in the code to control the servo’s movement as needed.

Conclusion

Controlling servo motors with an ESP32 is a relatively simple task that can be achieved with basic programming knowledge. By understanding the principles of PWM and the connections between the servo and ESP32, you can create a wide range of projects involving robotic movements and automation.