Section outline

  • Project: Wireless Robot in Action

    Time to bring everything together! In this final section, you’ll assemble your full Bluetooth-controlled robot, test it with the app, and troubleshoot any issues that arise during communication or movement.

    • 🔗 Final Circuit Setup and Wiring

      Make sure your connections are secure and complete. Here's a checklist:

      • Motor Driver: L298N module wired to both motors
      • Arduino: Connected to L298N and Bluetooth module
      • Bluetooth Module: HC-05 connected via TX/RX (use voltage divider on RX)
      • Power: External battery pack connected to motor driver (and optionally Arduino)

      Note: Double-check ground connections – all devices should share a common GND.

    • 📱 Testing App Control with Robot

      1. Turn on the robot and connect your phone to the HC-05 module.
      2. Open the Bluetooth control app (e.g., MIT App Inventor app you built).
      3. Test each button: Forward, Backward, Left, Right, and Stop.
      4. Observe how the robot reacts – motors should respond immediately.

      🛠 Debugging Communication Issues

      If the robot doesn’t respond as expected, check the following:

      • Baud Rate Mismatch: Ensure Arduino code uses the correct serial speed (usually 9600).
      • RX/TX Swapped: TX from Bluetooth should go to RX on Arduino, and vice versa.
      • App Command Mismatch: Confirm that the app is sending the correct characters expected by your Arduino code.
      • Power Issues: Motors may not respond if power is low or unstable.

      ✅ What You Achieved

      • Completed a functional wireless robot
      • Tested Bluetooth commands from a mobile app
      • Debugged real-time robot communication

      This project marks a big leap in your robotics journey. You’ve now built and controlled a robot remotely — a skill that opens up tons of creative possibilities ahead!