Hi everybody,
as a student team, we are in the process of developing a prandtlplane drone design. Sadly, it crashed during our test flight just after it had taken off. This is the second time it has crashed, in quite a similar way to the previous crash.
This time, we were able to retrieve the logs and capture the crash from multiple views. In the logs, the takeoff happens around 3.22, the crash happens around 3.26.
From our own analysis, we have some theories why this might happen:
- The standard PID values for controlling the pitch angle don’t work for our design, as setpoint and estimated value for the pitch angle don’t really overlap.
- By taking off in stabilized mode, which in hindsight wasn’t a logical decision, the pilot needs to respond too quickly when the plane takes off. Perhaps there is some kind of integrator windup which causes sufficient pitch downwards when the plane took off.
- The pixhawk flight controller is vibrating too much, giving wrong sensor inputs, therefore making bad controller decisions.
- The plane can simply not generate enough lift when the angle of attack changed after takeoff (i.e. the electronics seem fine, but there could be an aerodynamics problem).
Any other explanations or advice for future testing would be welcome.
Thanks in advance