The rotational speed threshold on fixed-wing vehicles is triggering easily
if the plane is lifted prior to takeoff (hand-launch), and can cause issues
for the auto takeoff state machine. Thus if either airspeed or groundspeed is valid,
it's better to rely on these for land detection, and only use the rotational
speed if they're invalid.
Signed-off-by: Silvan <silvan@auterion.com>
The RTL sequence from the navigator requires the vehicle to land. This is now handled for rovers by setting its state to landed if it is within the acceptance radius of the home position when in return mode.
* LandDetectorMC: enforce that LNDMC_Z_VEL_MAX * 1.2 is below *MPC_LAND_CRWL/MPC_LAND_SPEED
Otherwise the _in_descend flag doesn't get set correctly during the last part
of the landing, where the descend speed is at MPC_LAND_CRWL or LAND_SPEED.
The _in_descend flag is set it the velocity setpoint is >1.1*LNDMC_Z_VEL_MAX.
Signed-off-by: Silvan Fuhrer <silvan@auterion.com>
Co-authored-by: Matthias Grob <maetugr@gmail.com>
It's very important that the in descend detection is always
at a strictly higher velocity than the vertical movement check.
This combination is basically used to check for vertical downwards
velocity tracking. Desired descend, no movement -> ground
If in descend threshold is lower than vertical movement it is
by definition even with perfect tracking the case that with
any velocity between the two thresholds there is no movement
even though a descend is commanded.
See first fix of this problem #7831e39b38ba96
I don't see where this is necessary. During takeoff, the maybe landed flag should
only get cleared once system is about to takeoff, and thus well after the spool up
is complete (for which the higher thresholds are meant in this case).
Signed-off-by: Silvan Fuhrer <silvan@auterion.com>
Don't consider these params for vertical speed threshold,
and instead increase the default for LNDMC_Z_VEL_MAX and
use solely that one. Makes the land detector outcome more
predictable and its interal logic simpler, while the new
default tuning is resulting in about the same vz threshold
as before.
Signed-off-by: Silvan Fuhrer <silvan@auterion.com>
This commit removes the additional airspeed check (airspeed for VTOLs in
hover below LNDFW_AIRSPD_MAX), as it is not a required condition in the
landed state (headwind blowing into the airspeed sensor won't stop
once on the gruond). In FW mode the check would make more sense, but there
the land detector is currently simply disabled.
Signed-off-by: Silvan Fuhrer <silvan@auterion.com>
- move vehicle at reset detection ekf2 -> land_detector
- ekf_unit: reduce init period
- Fake fusion is when at rest is quite strong and makes the variance reduce rapidly. Reduce the amount of time we wait before checking if the variances are still large enough.
- ekf_unit: reduce minimum vel/pos variance required after init
- Fake pos fusion has a low observation noise, making the vel/pos variances reduce quickly.
Co-authored-by:: bresch <brescianimathieu@gmail.com>
Before: in_ground_effect was always true with the default settings (LNDMC_ALT_GND =-1)
and when a distance sensor was present with valid data.
Now: default of LNDMC_ALT_GND is set to 2m by default, and if set to a negative value
then in_ground_effect is never set to true
Signed-off-by: Silvan Fuhrer <silvan@auterion.com>
The both results of ?: should be of same type, and some compilers give error
on this:
" implicit conversion from 'float' to 'double' to match other result of conditional"
Signed-off-by: Jukka Laitinen <jukkax@ssrc.tii.ae>
For any normal use case where a downwards velocity setpoint is set
this works exactly the same as before.
E.g. autonomous landing, landing in Altitude or Position mode
The advantage is that the very common case where a vehicle tries
to hold a constant altitude but fails to do so e.g. during a hard brake
with too much lift the resulting downwards velocity was interpreted
as descend intent and since the vehicle already struggled to hold altitude
with low thrust and was not moving fast anymore because it was braking
this lead to a lot more false positives on certain vehicle types.
The disadvantage is that not setting a downwards velocity setpoint but
just moving the position setpoint into the ground does not result in
land detection anymore. We do not use this method of landing anymore for
quite a while. It's not recommended and I wonder if there's some rare use
case like offboard where this is done.
We could add an additional case for the specific case to land with a
position setpoint only.
The tree stages used arbitrary 350, 250 300ms totally 900ms
So this changes it to each stage to a third of the parameter.
Default it is 1 second -> 333ms per stage.
- if distance to the ground is available then hysteresis times will be increased
by a factor of 3 if vehicle is higher than 1m above ground
Signed-off-by: RomanBapst <bapstroman@gmail.com>
- parameter updates can be quite expensive because they trigger nearly all modules to reload all of their parameters immediately
- limit modules from updating faster than once per second
chfriedrich98