Reverse thrust for controlled landings, even with much steeper approach slopes. This is achieved by allowing throttle demand to go negative to maintain a target airspeed. A Pre-Flare stage was added, triggered by an altitude, to allow for a slower airspeed just before land. That lower airspeed can be near stall.
new params LAND_PF_ALT, LAND_PF_SEC, LAND_PF_ARSPD, USE_REV_THRUST
The PSTR is already define as a NOP for all supported platforms. It's
only needed for AVR so here we remove all the uses throughout the
codebase.
This was automated with a simple python script so it also converts
places which spans to multiple lines, removing the matching parentheses.
AVR-specific places were not changed.
we only accept a lidar if it changes by 5% of its full range, and we
reject a lidar again if the correction between barometric and lidar
range changes by more than 30m
This allows us to cope with faulty lidars which may give a constant
reading
when aborting a landing via mode change, check if NAV_CONTINUE_AND_CHANGE_ALT is after LAND. If so, go ahead and execute it. Else, normal behavior or check do_land_start else decrement mission index
- enabled via new param LAND_ABORT_THR default is 0 (disabled)
- Triggered via 95% throttle during landing, a landing abort will take place.
- This copies all takeoff params for right now, we can make this better later if needed
- added mission item command to NAV_LAND which is the abort takeoff altitude. If 0 then use last takeoff if available, else use 30m
- hold heading, just like takeoff, until altitude is reached
- pitch is constrained to takeoff pitch, or else 10deg if not available
- After abort altitude is reached, the normal landing restart happens (DO_LAND_START or decrement mission)
- restart landing by jumping to DO_LAND_START or decrement mission on mode change
If someone mistakenly puts all 0's in their LAND command then
total_distance will be calculated as 0 and cause a divide by 0 error
below thus crashing ArduPilot. Lets avoid that.