Section outline

  • Sensor Fusion – Combining Multiple Sensor Inputs

    Imagine a robot that avoids walls using an ultrasonic sensor and also follows a line using IR sensors. These are multiple inputs working together – this concept is called Sensor Fusion.

    • 🤖 What is Sensor Fusion?

      Sensor fusion is the process of using data from two or more sensors and combining them to make better decisions. It helps robots perform smarter actions based on a combination of inputs.

      🔄 Why Use Sensor Fusion?

      • One sensor might not be enough – combining improves reliability
      • Allows more accurate environment understanding
      • Reduces errors due to noise or limitations in one sensor

    • 📌 Real-life Examples:

      • Self-driving cars use cameras + radar + lidar
      • Smartphones use gyroscope + accelerometer for screen orientation
      • Drones use GPS + compass + barometer for stable flight

      🛠 Arduino Example: IR + Ultrasonic

      Let’s say we want a robot that follows a line but stops if there’s an obstacle ahead. Here's how logic works:

      1. IR sensors detect line and control steering
      2. Ultrasonic sensor checks for obstacles in front
      3. If obstacle < 10 cm, robot stops even if line is visible
      🧪 Sample Code Snippet:
      int distance = readUltrasonic();
int lineLeft = digitalRead(2);
int lineRight = digitalRead(3);

if (distance < 10) {
  stopMotors();
} else {
  if (lineLeft == LOW && lineRight == LOW) {
    moveForward();
  } else if (lineLeft == LOW) {
    turnLeft();
  } else if (lineRight == LOW) {
    turnRight();
  } else {
    stopMotors();
  }
}

      💡 Tips for Sensor Fusion

      • Start with simple logic — avoid overcomplicating
      • Test each sensor separately before combining
      • Use comments to keep logic clear and maintainable

      Sensor fusion helps your robot make better decisions — a critical step in moving from basic bots to intelligent ones. Up next, we’ll build a live multi-sensor display to visualize all this in action!