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PX4 / PX4-Autopilot

PX4 Autopilot Software
https://px4.io
BSD 3-Clause "New" or "Revised" License
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undesirable back-transition behavior. #16474

Open ghost opened 3 years ago

ghost commented 3 years ago

when using just the vtol-transition mission item in qgc, or flipping the switch from fw to mc mode stabilized mode, the curved path gets executed with a rolling behavior in the back transition

this is solved in the pr-vtol-rtl-fixes when using vtol transition and land mode, but however it still persists on the above mentioned conditions as the l1 controller is present in those two conditions in the back-transition.

Alternate Solution https://github.com/PX4/PX4-Autopilot/blob/d502292d0731a38c513dc1224c135b6f1965586e/src/modules/vtol_att_control/standard.cpp#L283 in the current master, _fw_virtual_att_sp->roll_body diverges from zero after some time in the back-transition, can we make it a hard zero as we don't want the aircraft to roll in the back-transition anyway?

To Reproduce to reproduce, in a mission set a vtol-transition mission item at the end of the mission. the behavior can be observed.

Expected behavior The vtol should transition to mc_mode in a straight line without going in a curved path with a roll.

Log Files and Screenshots https://review.px4.io/plot_app?log=1e1bb5d2-5260-40da-bd7e-46fadf55fc6c

Additional context i think this addresses the same issue https://github.com/PX4/PX4-Autopilot/issues/14933

https://github.com/PX4/PX4-Autopilot/pull/14405/files this introduced l1 controller to be present in the back transition which is good, but i think it needs to be further analyzed, cause this causes the aircraft roll in the back transition, which is not desirable.

LorenzMeier commented 3 years ago

Here is the PR: https://github.com/PX4/PX4-Autopilot/pull/16475

sfuhrer commented 3 years ago

Alternative solution, reduces the overshoots: https://github.com/PX4/PX4-Autopilot/pull/16499