Lift drag plugin usage

Hi, can you explain to me how aerodynamic parameters of the liftDrag plugin used in the IRIS quad demo in SITL / Gazebo was identified ?
Best regards


I got no idea. Did you read the lift drag paper, I think I remember that the parameters are closed to the default one’s or copied from px4 version

Hello, thx for your response. I have designed a 25 kg X8 with 29" x 9,5 propeller and i am searching a way to identify lift and drag plugin input params. I recently try with QBlade based on NACA 0018 foil but without success. Maybe a project with near characterictics exists …do you have already simulate an octa quad with ardupilot sitl gazebo ?
----- Mail d’origine -----

Hi. I have identified main aero param of a my own blade based on naca 0018. UAV mass is 25kg. It does not takeoff. Please how to set the multiplier value and other parameters?
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Well, the X8 UAV does beautiful takeoff but is unstable as described here by Eric Johnson

“” The drone takesoff and starts to oscillate varying its position by over a meter in radius.""

The problem is i already have the parameters in .world file who solved his problem.

The other solution based on the modification of the AHRS EKF mode 3 is unavailable.

v4.0.3 dev


To resolve this problem of instability do you think I can add plugin like barometer plugin and communicate directly with ardupilot via a new tcp link?
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We are already simulating the barometer.

You should check the performance of gazebo, normally you should be close to have the realtime update close to 1.

Otherwise try, AHRS_EKT_TYPE 10, it will allow you to check if you model is correct. The type 10 feed the drone with its real position.


After many iteration on
takeoff correct without any oscillations :slight_smile: but when it arrives at a waypoint with angle < 90° it seems YAW command is inverted !

Hi, from now UAV flights are good enough ! As the liftdragplugin sets rotor blade characteristics only, please could you explain which parameters in the ArduPilotPLugin correspond to motor limits ? (eg “multiplier” value vs rpm ? or eventually how to add them ?