Copter: Set Force Descend to true only when in the last phase of landing #17824
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
|
may need the same fix in quadplane |
rmackay9
reviewed
Jun 22, 2021
ArduCopter/mode.cpp
Outdated
| @@ -528,10 +529,11 @@ void Mode::land_run_vertical_control(bool pause_descent) | |||
| cmb_rate = MIN(-precland_min_descent_speed, -max_descent_speed+land_slowdown); | |||
| } | |||
| #endif | |||
| force_descend = (MAX(g2.land_alt_low,100) > get_alt_above_ground_cm()); | |||
There was a problem hiding this comment.
just as a small style thing, I think we should move this above the, "#if PRECISION_LANDING == ENABLED" line.
lthall
force-pushed
the
20210621_PR_LandForceDecendFix
branch
from
8375b10 to
c7dabf6
Compare
|
I tested this in SITL and it seemed to be setting the ignore_descent_limits flag at the right time so merged, thanks! |
# for free
to join this conversation on GitHub.
Already have an account?
# to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
This PR fixes a problem where the aircraft crashes into the ground it the decent speed is greater than the maximum descent speed the aircraft is capable of. Land currently sets Force_Desend to true at all times. This PR changes this to only be true in the last phase of landing or when land_detect_maybe is true.
Before:
After:
This problem was discovered when descending with the callisto from 500m at 15m/s. This worked very well until we used land rather than a waypoint in a mission. The aircraft's terminal velocity is ~13m/s and attempting to descend at 15m/s resulted in the aircraft impacting the ground at 4m/s. No damage was done (sand) but this is a problem others may face.