fix(navigator): keep a VTOL in multicopter mode through mission RTL - #28399
dakejahl merged 2 commits into
Conversation
Sorry, something went wrong.
🔎 FLASH Analysispx4_fmu-v5x [Total VM Diff: -160 byte (-0.01 %)] FILE SIZE VM SIZE
-------------- --------------
+0.0% +47 [ = ] 0 .debug_abbrev
-0.0% -2.61Ki [ = ] 0 .debug_info
-0.0% -314 [ = ] 0 .debug_line
+40% +2 [ = ] 0 [Unmapped]
-0.0% -316 [ = ] 0 [section .debug_line]
-0.0% -48 [ = ] 0 .debug_loclists
-0.0% -8 [ = ] 0 .debug_rnglists
+1.5% +160 [ = ] 0 [Unmapped]
-0.0% -160 -0.0% -160 .text
+11% +4 +11% +4 Takeoff::on_activation()
-4.2% -48 -4.2% -48 RtlDirectMissionLand::setActiveMissionItems()
-14.9% -52 -14.9% -52 RtlMissionFastReverse::setActiveMissionItems()
-11.4% -64 -11.4% -64 RtlMissionFast::setActiveMissionItems()
-0.0% -2.93Ki -0.0% -160 TOTAL
FILE SIZE VM SIZE
-------------- --------------
+0.0% +47 [ = ] 0 .debug_abbrev
-0.0% -2.61Ki [ = ] 0 .debug_info
-0.0% -314 [ = ] 0 .debug_line
+40% +2 [ = ] 0 [Unmapped]
-0.0% -316 [ = ] 0 [section .debug_line]
-0.0% -48 [ = ] 0 .debug_loclists
-0.0% -8 [ = ] 0 .debug_rnglists
+2.3% +160 [ = ] 0 [Unmapped]
-0.0% -160 -0.0% -160 .text
+11% +4 +11% +4 Takeoff::on_activation()
-4.2% -48 -4.2% -48 RtlDirectMissionLand::setActiveMissionItems()
-14.9% -52 -14.9% -52 RtlMissionFastReverse::setActiveMissionItems()
-11.4% -64 -11.4% -64 RtlMissionFast::setActiveMissionItems()
-0.0% -2.93Ki -0.0% -160 TOTAL
Updated: 2026-09-02T22:57:33 |
Sorry, something went wrong.
There was a problem hiding this comment.
This makes sense, I guess expected behaviour is then
- any type of mission RTL while in fixed-wing - do the mission RTL as it would be in FW
- any type of mission RTL while in MC - do the entire RTL in MC
If we are kilometers away from home it makes little sense to start a long mission without front-transition. I guess the alternative solving that would be:
- remove/weaken said vtol_att_control_main snippet and allow the transitions.
- modify rtl direct to include such a front-transition only if far enough for it to be worthwhile (I think at the moment it does the entire RTL as a multicopter)
Did you consider and reject this alternative?
- If yes this is good to go after removing the other, equally broken snippets. Please outline the reason for rejecting the alternative then :)
- If not, could you consider if the alternative reaches the goal in a simpler way while allowing sensible RTL from far away while in MC mode?
Thanks a lot in any case!
Sorry, something went wrong.
Remove the unconditional multicopter-to-fixed-wing transition from direct mission-land RTL so the return uses the VTOL mode active when RTL starts. This allows an MC-mode vehicle to proceed through the mission landing sequence instead of becoming stuck after an unnecessary forward transition. Add module-level and MAVSDK SITL regressions covering an airborne multicopter-mode VTOL with a planned mission landing. Refs PX4#27817 Refs PX4#24323 Assisted-by: Codex:gpt-5 Signed-off-by: Saibernard Yogendran <bernie97@seas.upenn.edu>
…s too The fast and the reverse mission RTL carried the same request for a transition to fixed wing as the direct mission land RTL. The VTOL attitude controller rejects that command during RTL, so a VTOL in multicopter mode waited on it forever instead of flying the mission. Remove both. A VTOL in multicopter mode now flies the mission RTL as a multicopter, the same as direct RTL does. Reported in PX4#24323. Two unit tests pin the active item to a waypoint for a VTOL in multicopter mode, and two MAVSDK cases fly it on the standard VTOL in SIH: the mission landing and the reverse mission both stay in multicopter mode to touchdown, within 5 m of the land item and of home. Assisted-by: Claude:claude-fable-5 Signed-off-by: Saibernard Yogendran <bernie97@seas.upenn.edu>
|
Thanks for taking a look. The other two snippets are the same code, and the attitude controller has been refusing MC to FW transitions in RTL since 2020, so all three ask for something that can never happen and the navigator just waits on it. I removed them as well and added a unit test and a SITL flight for each mode. The vehicle stays a multicopter through the mission landing and through the reverse mission. I did not go down the road of allowing a transition during RTL. I kept the change small because it makes mission RTL do what direct RTL already does for a VTOL in MC, which is the whole return in MC, and it removes a path that cannot complete. A distance based front transition would help on long returns, but it means weakening the transition block in the attitude controller and deciding when to transition and what to do if it fails. That felt bigger than this fix, so I left it out. If you think it is worth doing I can open a separate PR for it once this one is in. |
Sorry, something went wrong.
mbjd
left a comment
There was a problem hiding this comment.
Makes sense, I agree with this fix.
Being in MC but far away from home is a rare enough edge case that we don't need to fix it right here right now. Entering RTL in MC will now fly the entire RTL in MC rather than not at all, which is a clear improvement.
We can take care of a more nuanced implementation (transition if too far to fly in MC) in a next step.
Sorry, something went wrong.
…28399) * fix(navigator): preserve VTOL mode in direct mission RTL Remove the unconditional multicopter-to-fixed-wing transition from direct mission-land RTL so the return uses the VTOL mode active when RTL starts. This allows an MC-mode vehicle to proceed through the mission landing sequence instead of becoming stuck after an unnecessary forward transition. Add module-level and MAVSDK SITL regressions covering an airborne multicopter-mode VTOL with a planned mission landing. Refs #27817 Refs #24323 Assisted-by: Codex:gpt-5 Signed-off-by: Saibernard Yogendran <bernie97@seas.upenn.edu> * fix(navigator): drop the fixed wing transition from the fast RTL modes too The fast and the reverse mission RTL carried the same request for a transition to fixed wing as the direct mission land RTL. The VTOL attitude controller rejects that command during RTL, so a VTOL in multicopter mode waited on it forever instead of flying the mission. Remove both. A VTOL in multicopter mode now flies the mission RTL as a multicopter, the same as direct RTL does. Reported in #24323. Two unit tests pin the active item to a waypoint for a VTOL in multicopter mode, and two MAVSDK cases fly it on the standard VTOL in SIH: the mission landing and the reverse mission both stay in multicopter mode to touchdown, within 5 m of the land item and of home. Assisted-by: Claude:claude-fable-5 Signed-off-by: Saibernard Yogendran <bernie97@seas.upenn.edu> --------- Signed-off-by: Saibernard Yogendran <bernie97@seas.upenn.edu> (cherry picked from commit 290f56d)
Summary
An MC-mode VTOL can now enter its planned mission landing without an unnecessary forward transition. The same applies to the fast and the reverse mission RTL. A VTOL that enters RTL in multicopter mode flies it as a multicopter, the same as direct RTL.
Problem
Direct mission-land RTL forced MC-mode VTOLs into fixed-wing mode at return altitude. The vehicle could remain armed instead of starting the landing sequence.
Solution
Preserve the current VTOL mode and advance directly to DO_LAND_START. The fast and the reverse mission RTL carried the same transition request, which the VTOL attitude controller rejects during RTL, so it is removed there as well, with a unit test and a SITL flight for each mode. This addresses the forced-transition behavior in #27817 and #24323; the separate invalid-mission race in #27817 remains out of scope.