2024-03-03 03:14:09 -04:00
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# Plane Precision Landing
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This script implements a precision landing system for VTOL fixed wing
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2024-03-07 03:12:26 -04:00
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aircraft (quadplanes).
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Precision positioning over a landing sensor is supported in QLOITER,
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QLAND, QRTL and AUTO landing.
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2024-03-03 03:14:09 -04:00
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# Parameters
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Beyond the normal PLND parameters the script adds 2 additional parameters to
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control it's behaviour. The parameters are:
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## PLND_ALT_CUTOFF
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This is an optional altitude in meters below which the precision
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landing system will stop correcting the landing position. Many
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precision landing sensors have poor performance at low altitudes, so
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setting this to around 5 meters is advisable. A value of zero disables
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this cutoff.
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## PLND_DIST_CUTOFF
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This is a maximum horizontal distance in meters that will be accepted
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for a landing corrections. If this parameter is greater than zero and
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the precision landing subsystem gives a distance beyond this distance
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then precision landing correction will stop and the last landing
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position will be used.
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# Operation
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You should first install and configure a precision landing sensor as described here:
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https://ardupilot.org/copter/docs/precision-landing-with-irlock.html
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then you should enable the precision subsystem and install the lua
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script in the APM/scripts folder of your flight controller.
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The script will start adjusting the landing position only when in the
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descent phase of an automatic VTOL landing. The PPLD log message can
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be used to analyse the performance of the precision landing.
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It is advisable to have a manual pilot able to take over control in a
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mode such as QLOITER for instances where the precision landing system
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may malfunction.
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## Moving Target
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If the PLND_OPTIONS bit for a moving target is enabled then the
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vehicle will be set to track the estimated target velocity during
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descent
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2024-03-07 03:12:26 -04:00
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## Precision QLoiter
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To enable precision position hold in QLOITER you will need to use
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auxiliary function 39 (PRECISION_LOITER) on an R/C switch or via GCS
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auxiliary switch buttons. When enabled the vehicle will position
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itself above the landing target. Height control is under user control.
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