Airspeed sensor calibration sensitivity

Hi,

I am working on a fixed-wing UAV and my airspeed sensor is digital MATEK 4525DO. I have calibrated the sensor with the AUTO_CAL parameter and the ARSPD_RATIO value fell around smaller than 2. This looks normal. But on the ground when I power the pixhawk, the airspeed value is changing around 7 m/s. I think this is too much. When we blow the pitot tube, the airspeed value increases to around 20 m/s. Is there any mistake? Or is the sensitivity of the speed sensor normal as well? Has anyone had a problem like this before?

Thanks for helping.

Make sure you loosely cover the pitot tube when you boot up the plane. It will calibrate during itÔÇÖs startup and if thereÔÇÖs a wind or breeze when itÔÇÖs booting it will offset the calibration.

If you forget you can also cover the pitot tube once itÔÇÖs booted up and use MP to do a pre-flight calibration.

First of all thanks for your reply. When I was booting the pixhawk, I covered the pitot tube loosely. After the calibration, the airspeed value came as I mentioned first. So after that, I wanted to do a preflight calibration. But when I clicked the button, MP got an error like ÔÇťThe command failed to executeÔÇŁ. Why I got this error? Where am I mistaking I do not know?

Is there any other idea or suggestion ? Thanks

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Ayn─▒ sorun ile kar┼č─▒la┼č─▒yorum ├ž├Âz├╝m├╝n├╝ bulabildiniz mi acaba ?

Sens├Âr ─▒┼č─▒ktan etkileniyor, yanl─▒┼č ├Âl├ž├╝mler yapabiliyor. ├ťzerini siyah bant ile veya ba┼čka bir y├Ântemle kapat─▒p tekrar boot edince d├╝zelmesi laz─▒m diye hat─▒rl─▒yorum.

te┼čekk├╝r ederim ama tam olarak anlayamad─▒m siyah bantla kapatt─▒ktan sonra preflight d├╝zelecek mi ├ž├╝nk├╝ ben de ayn─▒ hatay─▒ al─▒yorum ÔÇťThe command failed to executeÔÇŁ yaz─▒yor birde i┼čim bittikten sonra bant─▒ ├ž─▒karaca─č─▒m de─čil mi ?

Preflight calibration mission plannerla ilgili bir durum. Sens├Âr├╝n ├╝zerini ─▒┼č─▒k almayacak bir ┼čekilde kapatmak (siyah bant veya ba┼čka bir ┼čey) sens├Âr├╝n do─čru ├Âl├ž├╝m yapmas─▒n─▒ sa─čl─▒yor. Aksi takdirde ├╝zerine ─▒┼č─▒k d├╝┼čerken farkl─▒, d├╝┼čmezken farkl─▒ ├Âl├ž├╝m yap─▒yor. Bu nedenle sens├Âr├╝n ├╝zerinin ─▒┼č─▒k almayacak ┼čekilde her zaman kapal─▒ durmas─▒ gerekli.
Arduplane d├Âk├╝mantasyonunda da ─▒┼č─▒k ile ilgili uyar─▒ var :
https://ardupilot.org/plane/docs/airspeed.html#airspeed-sensor-type

Bizim sens├Âr├╝m├╝z siyah makaron ile kapl─▒ pitot t├╝p├╝n├╝n kendisiyle alakal─▒ bir durum var m─▒ a─čz─▒n─▒n a├ž─▒k kalmas─▒ vs bir sorun yarat─▒r m─▒?

Bir de Autocal nas─▒l ├žal─▒┼č─▒yor nas─▒l kalibre edece─čiz pitot t├╝p├╝n├╝

https://ardupilot.org/plane/docs/calibrating-an-airspeed-sensor.html#calibrating-an-airspeed-sensor

Burada sorular─▒n─▒z─▒n cevab─▒ yer al─▒yor detayl─▒ bir ┼čekilde.