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09 - Bluetooth Remote Control Car

Introduction​

![grapebit_bluetooth_car](./09 - bluetooth car.assets/grapebit_bluetooth_car.png)

The Grapebit board, known for its cost-effectiveness as a programming controller, is often used in lightweight projects. For remote control projects, it usually requires an additional Grapebit or Future Board for ESP-NOW broadcasting, which adds to the project’s overall cost.

This project aims to reduce costs for Grapebit remote control projects by connecting a commonly available Bluetooth controller to the Grapebit board for remote control.

Materials Needed​

![grapebit_bluetooth_car2](./09 - bluetooth car.assets/grapebit_bluetooth_car2.png)

Bluetooth Controller​

We’ve chosen a standard Bluetooth controller available on the market, featuring 14 programmable buttons (the home button is not usable).

![bluetooth_gamepad](./09 - bluetooth car.assets/bluetooth_gamepad.png)

Bluetooth Car Project​

To help users get started and understand how to use the Grapebit and Bluetooth controller, we’ll build a remote-controlled car.

The Grapebit can drive two motors in one direction each. It will pair directly with the Bluetooth controller, and upon receiving button commands, the Grapebit will respond accordingly.

![grapebit](./09 - bluetooth car.assets/grapebit.png)

Wiring​

You can assemble a simple two-wheeled car according to your preference. Connect the two motors to the Grapebit board, and attach the Kittenbot lithium battery pack for power.

![bluetooth_car_wiring](./09 - bluetooth car.assets/bluetooth_car_wiring.png)

Quick Programming​

Update Plugins and Firmware​

  • Connect the Grapebit to your computer via USB.

  • Ensure the Grapebit hardware plugin is updated to v2.1.0 or higher. (If not updated, a green upgrade icon will be displayed) ![kittenblock_grapebit](./09 - bluetooth car.assets/kittenblock_grapebit.png)

  • Set the Grapebit into firmware recovery mode by holding down the B button and pressing the Reset button, then click "Restore Firmware" to update to the latest firmware (only needs to be done once).

    ![grapebit_reset](./09 - bluetooth car.assets/grapebit_reset.png) ![kittenblock_firmware](./09 - bluetooth car.assets/kittenblock_firmware.png)

  • Reconnect the Grapebit.

    ![kittenblock_firmware2](./09 - bluetooth car.assets/kittenblock_firmware2.png)

  • Load the Bluetooth controller plugin.

    ![image-20241106145615288](./09 - bluetooth car.assets/bluetooth_ controller_plugin.png)

  • Write and upload the program for controlling the Grapebit’s LED with the Bluetooth controller.

    ![kittenblock_upload](./09 - bluetooth car.assets/kittenblock_upload.png)

  • Turn on the Bluetooth controller and wait for the Grapebit to pair automatically (usually within 10 seconds). If pairing fails, press the Reset button on the Grapebit to retry.

    ![pair](./09 - bluetooth car.assets/pair.png)

  • Test the connection.

    According to the program logic, press the up and down buttons on the controller to turn the Grapebit’s LED on and off.

    ![grapbit_onoff](./09 - bluetooth car.assets/grapbit_onoff.gif)

Bluetooth Car​

Assembly​

Assemble a two-wheeled car to your liking.

![grapebit_car](./09 - bluetooth car.assets/grapebit_car.jpeg)

Car Program​

Modify the program to include motor movement. Note that the Grapebit’s two motor drives only support one-way rotation.

If the motor behavior does not match the program, try reversing the motor wires or swapping M1 and M2 motor connections.

![kittenblock_bluetooth_code](./09 - bluetooth car.assets/kittenblock_bluetooth_code.png)

Download​

![kittenblock_upload2](./09 - bluetooth car.assets/kittenblock_upload2.png)

Final Result​

![grapebit_car_bluetooth](./09 - bluetooth car.assets/grapebit_car_bluetooth.gif)