Hardware-in-the-Loop Testing for Robots & Drones

I have outlined the HIL test bench architecture and the automated test script for your STM32 motor controller. This setup focuses on protecting your hardware while injecting the rotor stall fault.

HIL Bench Architecture & Test Script

# test_motor_faults.py
import pytest
from hardware_drivers import PowerSupply, DAQ, Programmer

@pytest.fixture
def bench():
    psu = PowerSupply(port='/dev/ttyUSB0')
    daq = DAQ(device_id='Dev1')
    prog = Programmer(target='stm32f4x')
    
    psu.set_voltage(12.0)
    psu.set_current_limit(2.0)
    yield psu, daq, prog
    psu.output_off()

def test_rotor_stall_protection(bench):
    psu, daq, prog = bench
    
    # 1. Flash latest firmware
    prog.flash('build/motor_controller.bin')
    psu.output_on()
    
    # 2. Simulate nominal operation
    daq.set_analog_output('current_sense_pin', 0.5) # 0.5A nominal
    
    # 3. Inject Fault: Rotor Stall (Current Spike)
    daq.set_analog_output('current_sense_pin', 5.0) # 5A stall simulation
    
    # 4. Verify Response
    pwm_duty = daq.read_pwm_duty('motor_pwm_pin')
    assert pwm_duty == 0, "Firmware failed to cut PWM during over-current"
    
    # 5. Log Telemetry
    print(f"Shutdown latency: {daq.get_last_event_timing()} ms")

Next steps

1. Review the electrical isolation requirements between the DAQ analog output and the STM32 ADC pins.
2. Calibrate the plant model constants (resistance, inductance) to match your physical motor.
3. Add a test case for brown-out recovery by cycling the PSU voltage to 3.3V during operation.