Hi everyone,
I’m working on a drone that uses ArduPilot for precision landing into a box (85x85 cm) with a hatch that raises up to 120 degrees. The landing platform lifts up to the box edge. The drone relies on a MAVLink-based precision landing system, which provides accurate landing target messages. The landing process works, but there are two major issues:
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Turbulence Near Hatch – When the drone gets close to the box, the airflow interactions between the props, the hatch, and the box edges creates turbulance, which causes small movements for the drone, which in turn causes small oscillations and can cause the drone to drift and potentially hit the hatch.
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Wind Shadow Effect Causes Sudden Drift – In strong wind conditions, the hatch blocks the wind, and as the drone descends near it, the sudden loss of wind force makes the drone unexpectedly drift into the hatch or cause instability.
We have tried landing in better conditions: the precision landing messages are correct, and the drone does land on the target, there are no issues with that.
We have played around with all the precision land parameters and some position control tuning, but the issue persists. The position control in other cases works fine, for example in loitering.
The effect is especially noticeable in strong wind conditions.
We cannot change the box for the time being, but is there something to be done for the drone to keep itself more strictly on the target? If tuning can help, then which part of the control pipeline to start with?
Has anyone dealt with similar issues when landing in a confined space with turbulent airflow?
Are there any more parameter tweaks (beyond the usual LAND_SPEED/PID tuning) that could help stabilize descent near the hatch?
Would modifying EKF wind estimation settings help mitigate the wind shadow effect?
Any other ideas to reduce oscillations and improve landing accuracy in these conditions?
Thanks in advance for any help or suggestions!