🎯 Exercise #5: "The Curious Head" 🤖

In this challenge, you'll create a simple robot head that "looks around" based on feedback from a distance sensor. The motor will move left and right like it's curious about its environment, and it will stop if an object gets too close.

🛠️ Your Challenge:

1. Use the HC-SR04 distance sensor to measure the distance to an object.
2. Control a stepper motor to turn left and right continuously.
3. If the sensor detects an object within 10 cm, the motor should stop and look at the object.

🔧 Components You'll Use:

- 5V Stepper Motor
- ULN2003 Driver Board
- HC-SR04 Distance Sensor
- Arduino Board
- Breadboard and Wires

🧩 Hints for Your Code:

- Use the `millis()` function to manage the motor's timing.
- Use sensor feedback from the HC-SR04 to decide when to stop the motor.
- Alternate the motor’s direction every few seconds (like a robot "scanning" its surroundings).

🧠 What You’ll Learn:

1. Combining sensors and motors for interactive behavior.
2. Creating feedback loops — a key concept for robot decision-making.
3. Making your robot respond to its environment in real time.