Smart Board
Turn a balance board into a Bluetooth game controller and a motion-data recorder.
An ESP32-C6 with an MPU6050 (gyro + accelerometer) sits inside the board.
- Game controller: the board pairs with your PC as a Bluetooth keyboard. Lean to press W/A/S/D (diagonals too). If the board's edge touches the ground, keys release and you get a warning; the 3rd touch locks the keys for up to 5 s.
- Data streaming: sends
gx,gy,gz,ax,ay,az,timestamp over BLE every 50 ms (Nordic UART Service).
- Labelling app: record labelled motion (neutral, tilt left, touching right, circle...) into CSV for training a model.
Website: https://smartboardapp.vercel.app
The ESP32-C6 has no Classic Bluetooth, so everything uses BLE (no BluetoothSerial).
What's in here
| Path | What it is |
|---|
firmware/smart_board_controller/ | Game-controller firmware (BLE HID keyboard). Logic is in board_logic.h (plain C++). |
firmware/smart_board_stream/ | Streams raw sensor lines over BLE (NUS) at 20 Hz. |
firmware/i2c_scan/ | Finds which pins your MPU6050 is wired to and its chip ID. |
tools/smart_board_logger.py | Connects to the stream firmware, prints lines live, saves a CSV to your Desktop. |
tools/smart_board_labeler.py | Desktop app (tkinter) to record labelled takes. --demo runs without a board. |
web/ | The project's landing page. |
Hardware
- ESP32-C6 board (tested on a Pcbcupid Glyph C6)
- MPU6050 module (MPU6500-type clones that report WHO_AM_I
0x70 also work)
- Wiring used here: SDA = GPIO17, SCL = GPIO16, VCC = 3.3 V, GND = GND
Different wiring? Flash firmware/i2c_scan, open Serial Monitor at 115200, and put the pins it finds into I2C_SDA / I2C_SCL at the top of the firmware.
Build and flash (Arduino CLI)
Needs the ESP32 Arduino core 3.x. Board: esp32:esp32:Pcbcupid_GLYPH_C6 (or esp32:esp32:esp32c6).
arduino-cli core install esp32:esp32
arduino-cli compile --fqbn esp32:esp32:Pcbcupid_GLYPH_C6 firmware/smart_board_controller
arduino-cli upload -p COM17 --fqbn esp32:esp32:Pcbcupid_GLYPH_C6 firmware/smart_board_controller
Replace COM17 with your board's port. The stream firmware also needs the
MPU6050 library by Electronic Cats (arduino-cli lib install MPU6050). If another installed library also provides MPU6050.h, pass --library <path to this one> when compiling.
Using the game controller
- Pair once: Windows Settings > Bluetooth > Add device > Smart Board.
- Calibrate once: hold BOOT for 2 s (or type
c in Serial Monitor at 115200). Within 4 s step on, stand level and still, then lean forward firmly and hold. It prints Calibrated and saved. Play!.
- Lean about 4 degrees to press a key.
Serial commands: c recalibrate, d live data on/off, r factory calibration, ? help.
Recording data
Flash firmware/smart_board_stream, then:
pip install bleak
python tools/smart_board_logger.py # live lines + CSV on your Desktop
python tools/smart_board_labeler.py # labelling app (add --demo to try without a board)
Only one program can connect to the board at a time.
Troubleshooting
- Compiler fails with
cc1plus.exe: CreateProcess, Access is denied or Permission denied (Windows): a third-party antivirus may be blocking the compiler from being started by arduino-cli. Excluding the toolchain folders or using Windows Defender fixed it here.
MPU6050 not found: run the I2C scanner. Both lines reading 0 V means the sensor has no power or isn't on those pins.- Crash at
hid->manufacturer(...) on core 3.3.x: use hid->manufacturer()->setValue("...") (already done here).
License
MIT
