07. Robotics with Arduino

⚙️ Types of Motors Used in Robots

• DC Motor – Spins in one direction or the other. Simple and fast.
• Servo Motor – Rotates to a specific angle (0° to 180°). Great for precise control.
• Stepper Motor – Moves in small steps. Used in CNC machines and printers.

🔌 Connecting a DC Motor to Arduino

You can't connect a DC motor directly to an Arduino. Why?

• Motors need more current than Arduino can provide.
• To reverse motor direction, we need a special circuit.

This is where a motor driver like the L298N or L293D comes in. It acts like a middleman that lets Arduino control the motor safely.

📦 Components Needed

• 1 x Arduino Uno
• 1 x L298N or L293D Motor Driver
• 2 x DC motors (like BO motors)
• 1 x External power source (battery or USB power bank)
• Jumper wires

🔁 Controlling Motor Direction with Code

Here's a simple example of Arduino code to spin a DC motor in both directions using a motor driver:

// Motor pins
int in1 = 7;
int in2 = 8;

void setup() {
  pinMode(in1, OUTPUT);
  pinMode(in2, OUTPUT);
}

void loop() {
  // Forward
  digitalWrite(in1, HIGH);
  digitalWrite(in2, LOW);
  delay(1000);

  // Reverse
  digitalWrite(in1, LOW);
  digitalWrite(in2, HIGH);
  delay(1000);
}

📘 How the Code Works

• in1 and in2 are connected to the motor driver.
• Setting one HIGH and the other LOW moves the motor in a specific direction.
• Switching the HIGH/LOW values reverses the direction.

🧠 Important Tips

• Always use a separate power supply for motors to avoid damaging Arduino.
• If motors don’t spin, check wiring and motor driver connections.
• Use delay() for testing but consider more advanced timing later.

🏁 Up Next

Now that your robot can move, let’s teach it how to see where it’s going! In the next section, we’ll add line sensors and learn how to detect paths.