🧪 Testing and Feature Options

🎯 Lesson Objective

In this lesson, students will learn:

• How to test the Bluetooth Control Car
• How to connect the smartphone to the ESP32 via Bluetooth
• How to verify that commands are received correctly
• How to troubleshoot common problems
• Additional features that can improve the robot

This lesson focuses on testing the Bluetooth communication and robot movement.

1️⃣ Checking the Hardware Setup

Before testing the robot, verify that all hardware connections are correct.

Check the following:

✔ ESP32 powered properly
✔ Motor driver pins connected correctly
✔ Motors connected to correct output terminals
✔ Battery polarity correct
✔ All components share a common ground

Incorrect wiring may prevent the robot from moving correctly.

Always verify the circuit before powering the robot.

2️⃣ Uploading the Program

To begin testing the robot:

1️⃣ Connect the ESP32 to the computer using a USB cable.
2️⃣ Open Arduino IDE.
3️⃣ Select the correct ESP32 board.
4️⃣ Select the correct COM port.
5️⃣ Upload the program.

After the upload is complete, the ESP32 will start the Bluetooth system.

3️⃣ Connecting the Smartphone to ESP32

Follow these steps to connect the phone to the robot.

1️⃣ Turn on Bluetooth on your smartphone.
2️⃣ Open the Bluetooth settings.
3️⃣ Search for available devices.
4️⃣ Find the device named:

ESP32_Robot

5️⃣ Pair with the device.

Once paired, the smartphone can communicate with the ESP32.

4️⃣ Using a Bluetooth Control App

Students need a mobile app to send commands.

Common apps include:

📱 Bluetooth RC Controller
📱 Arduino Bluetooth Controller
📱 Bluetooth Terminal

These apps allow the user to send commands such as:

These commands are received by the ESP32 and processed by the program.

5️⃣ Testing Robot Movement

Once the phone is connected, test the robot movement.

Steps:

1️⃣ Open the Bluetooth control app.
2️⃣ Connect to ESP32_Robot.
3️⃣ Press the Forward button.

Expected behavior:

➡ Robot moves forward.

Next test:

• Press Left → robot turns left.
• Press Right → robot turns right.
• Press Backward → robot moves backward.
• Press Stop → robot stops.

If the robot performs these actions correctly, the system is working.

6️⃣ Complete Robot Test

Now test the robot in a real environment.

Testing process:

1️⃣ Place the robot on the floor.
2️⃣ Connect the phone to the robot.
3️⃣ Use the mobile app to control movement.
4️⃣ Drive the robot in different directions.

This confirms that the Bluetooth Control Car is functioning correctly.

7️⃣ Troubleshooting Common Problems

Students may encounter some common problems.

Problem: Phone cannot find ESP32

Possible causes:

• Bluetooth not enabled on ESP32
• Program not uploaded properly

Solution:

Restart ESP32 and check the program.

Problem: Robot not moving

Possible causes:

• Motor driver wiring incorrect
• Battery not supplying enough power
• Motors connected incorrectly

Solution:

Check the motor driver connections and power supply.

Problem: Commands not working

Possible cause:

Mobile app sending incorrect characters.

Solution:

Verify that the app sends the correct commands:

F, B, L, R, S

8️⃣ Improving the Bluetooth Robot

Once the robot works successfully, additional features can be added.

Possible improvements include:

⚡ Adding PWM speed control
📱 Creating a custom mobile control app
💡 Adding LED indicators for movement
📡 Adding WiFi control instead of Bluetooth

These improvements make the robot more advanced.

9️⃣ Real-World Applications

Bluetooth-controlled robots are used in many applications.

Examples include:

🚗 Remote-controlled vehicles
🤖 Tele-operated robots
🏭 Industrial equipment control
🏠 Smart home devices

Wireless communication allows machines to be controlled without physical connections.

🚀 What Happens Next

Now that you have successfully built and tested the Bluetooth Control Car, the next project will introduce voice-controlled robotics.