Commander: don't reset home position if landed during a mission

[mahima-yoga]

Solved Problem

If COM_HOME_EN is enabled, the home position will reset when landed.

However, during mission execution, we want to prevent the home position from resetting if an intermediate landing occurs. Instead, the home position should remain fixed at the one set at the beginning of the mission.

Solution

• Check whether the vehicle is still executing a mission before updating home position

To have multiple takeoff items in a mission: I found that this feasibility check fails and prevents you from uploading the mission. Commenting it out works for now, but is probably not a very robust solution.

Changelog Entry

For release notes:

Feature/Bugfix Don't reset home position until a mission is finished

Alternatives

We briefly discussed whether this should be a configuration option. These are the alternative options:

1. Extending COM_HOME_EN (or introducing a new parameter) that only sets the home_position once in a boot cycle (position where the vehicle was armed the very first time).

   • Pros: more generalized, and gives everyone the option to enable this feature
   • Cons: not explicitly linked to the mission. So the home_position won't update once the mission is finished.

2. Creating a mission parameter that enables multiple takeoffs. If enabled, home_position doesn't update upon each landing. Something like: MIS_MULTI_TKO_LND?

Test coverage

Tested in SITL:

• Simulation testing logs: https://review.px4.io/plot_app?log=ed5fd532-f0c1-4e75-9b37-5fa25f4096de

[dakejahl]

Nice! I like this solution better than the proposed alternatives

[sfuhrer]

Can you adapt the parameter description of COM_HOME_EN (add a note that Home is not reset if mission is not complete)?
And do I get it correctly that now if you fly a mission, then take over in a manual mode, land somewhere, takeoff off again --> Home is not updated?

[github-actions]

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Updated: 2025-05-28T13:45:58

[mahima-yoga]

And do I get it correctly that now if you fly a mission, then take over in a manual mode, land somewhere, takeoff off again --> Home is not updated?

@sfuhrer When you take over the nav_state is no longer NAVIGATION_STATE_AUTO_MISSION, so the home position should update again when landed/taking off. Quickly tested it as well, home position updates: