BLDC Test Bench

This project is an automated test bench for BLDC motor and propeller characterization using an STM32F407VET6 microcontroller. The system drives the motor through a predefined test sequence and logs thrust, torque, voltage, current, and RPM data to an SD card.

📋 Features

• Automatic Motor Control: Runs a step-based acceleration ramp (for example, 10% duty-cycle steps every 2 seconds).
• Sensor Monitoring:
  • Voltage: INA219 (I2C).
  • Current: ACS758 (analog).
  • Force (Thrust/Torque): Load cells with HX711 amplifiers.
  • RPM: SNG-QPLA-000 speed sensor (interrupt-based).
• Data Logging: Records measurements to CSV files on an SD card.
• RTC Timestamping: Includes date/time information in log filenames.
• Interface: Serial monitor for debug and a physical button to start/stop tests.

🛠 Hardware

• Microcontroller: STM32F407VET6 (Black Board)
• Sensors:
  • INA219 module (Voltage/Current - primarily used here for voltage)
  • ACS758 current sensor
  • HX711 amplifiers (for load cells)
  • Honeywell SNG-QPLA-000 speed sensor (Quadrature Speed and Direction Sensor)
• Actuation: ESC (Electronic Speed Controller) for BLDC motor
• Storage: SD card module

🔌 Pinout

Peripheral	STM32 Pin	Function
Motor (ESC)	PD13	PWM signal
Start Button	PE4	Button (Input Pullup) - Start/Stop sequence
RPM Sensor	PD12	Pulse input (interrupt)
I2C (INA219)	PB6	SCL
	PB7	SDA
SD Card	PA7	MOSI
	PA6	MISO
	PA5	CLK
	PC11	CS
SD Detect	PD2, PC8, PC12	Detection pins (check wiring/schematic)

Note: The code may reference PE3 in log messages, but the functional button pin is configured as PE4.

🚀 How to Use

1. Assembly: Connect all sensors and the ESC according to the pinout above.
2. SD Card: Insert a FAT32-formatted SD card.
3. Power: Supply both the board and the motor power stage.
4. Start:
   • The system boots and performs current offset calibration (tare).
   • Wait for the "SISTEMA PRONTO" message on the serial monitor.
   • Press the button connected to PE4.
5. Test Run:
   • The motor executes the acceleration step sequence.
   • Data is printed to serial and saved to SD.
   • At the end of the sequence, the motor is turned off automatically.

📂 Project Structure

• src/main.cpp: Main loop, SD management, and orchestration.
• src/ControlarMotor.cpp: State machine for motor PWM control.
• src/MedirCelulasdeCarga.cpp: Load-cell (HX711) reading routines.
• src/MedirCorrente.cpp: ACS758 current measurement.
• src/MedirTensao.cpp: INA219 voltage measurement.
• src/MedirRPM.cpp: Pulse counting and RPM calculation.

📈 Experimental Results

The following plots summarize the recorded datasets in Experiments/air and Experiments/water.

Air Tests - 2312 Motor

Air Tests - 3508 Motor

Air Tests - 3508 Failed Run

Water Tests - T200

📦 Dependencies

Libraries are managed automatically by PlatformIO in platformio.ini:

• arduino-libraries/SD
• bogde/HX711
• stm32duino/STM32duino RTC
• adafruit/Adafruit INA219

⚙️ Configuration

To adjust parameters such as pin mapping, sensor calibration, or acceleration profile settings, edit the corresponding .h files in src/ or the top-level definitions in each .cpp file.

📚 How to Cite

If you use this project in academic work, please cite it as:

@misc{bldc_test_bench,
  author       = {Jardel Prado},
  title        = {Propulsion of Hybrid Aerial-Underwater Vehicles: Experimental Setup and Dataset},
  year         = {2026},
  howpublished = {Brazilian Conference on Robotics - CROS}
}