fix(navigator): enforce NAV_MIN_LTR_ALT in MC braking loiter#27680
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fix(navigator): enforce NAV_MIN_LTR_ALT in MC braking loiter#27680saad1551 wants to merge 1 commit into
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🔎 FLASH Analysispx4_fmu-v5x [Total VM Diff: 48 byte (0 %)]px4_fmu-v6x [Total VM Diff: 48 byte (0 %)]Updated: 2026-06-17T05:19:54 |
When a multicopter enters Hold (AUTO.LOITER) below NAV_MIN_LTR_ALT the documented behavior is to first climb to that minimum altitude. The clamp was added in 2022 to setLoiterItemFromCurrentPosition (the fixed-wing branch) but never applied to the sibling setLoiterItemFromCurrentPositionWithBraking, which is the rotary-wing Hold path selected at loiter.cpp:131. As a result, multicopters silently held at the entry altitude. Apply the same min-altitude clamp in the braking variant so the rotary-wing path matches the fixed-wing one. Verified in SITL (jMAVSim x500): with NAV_MIN_LTR_ALT=20 and Hold engaged from a 5m hover, the vehicle now climbs to 20m as documented. Fixes PX4#27578 Signed-off-by: saad1551 <saad.ashraf.9094@gmail.com>
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Multicopter Hold/AUTO.LOITER silently ignores
NAV_MIN_LTR_ALTwhen entered below the configured altitude, contradicting the documented behavior. The min-altitude clamp was added toMissionBlock::setLoiterItemFromCurrentPositionin 2022 but never applied to the siblingsetLoiterItemFromCurrentPositionWithBraking, which is the multicopter Hold path selected atloiter.cpp:131(vehicle_type == ROTARY_WING). Fixed-wing keeps working because it takes the non-braking branch.This PR copies the same four-line clamp into the braking variant so the rotary-wing path matches.
Reproduced and verified in SITL (jMAVSim x500):
NAV_MIN_LTR_ALT=20, Hold entered at ~5 m → vehicle held at 5 m for 30 s.Local sanity:
make px4_sitlbuilds cleanmake px4_fmu-v6xnot built locally (no arm toolchain on this machine — CI covers it)Fixes #27578