Pwm And RPM Issue (Solved-There is no issue)

ArduCopter
1

We are using ArduPilot v4.6.2 with BDShot firmware and DShot 300 ESCs. During ground testing (no propellers), after arming the drone and increasing throttle to about 50%, the motor PWM did not vary — it stayed between 1100–1200 . When the throttle was increased above ~50%, PWM jumped directly from ~1100 to ~1800+. All motor/ESC-related parameters are at their default values. However, during flight testing the drone took off and hovered correctly at expected PWM values.

Motor: Machtech DM7006 340KV
ESC: APD ESC 80A
Propeller: 28 inch
Drone maximum weight: 10 kg
Operating modes tested: Stabilize, AltHold

2

That is normal, because without props, you are testing a closed loop control system in an open-loop configuration. So it just behaves like that.

Once you put props on it and let it fly, it closes the control loop and things start to work as expected.

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