Hello everyone, I have question about this parameter ARSPD_RATIO. USING ARSPD_AUTOCAL and going in a circle at 100m for around 10 min we got ARSP_RATIO of 3.2. In the documentation it mentions the ARSPD_RATIO for analog sensors should be less than 3 however, we are using a digital air speed sensor. Is it okay to keep using this value?
I used an analog airspeed sensor. After analyzing Log files with UAV LogViewer, I got a value of ARSPD_RATIO 4.78. The reason for this coefficient is a small hole of dynamic pressure in the Pito tube. I measured holes in different Pito tubes that I bought from different sellers, they differ in the size of the dynamic hole. For an analog airspeed sensor, the hole should be larger, this is obvious because the different characteristics of the pressure transducers. However, I trusted the ARSPD_RATIO value of 4.78, my test flight was successful, I was able to adjust the PID coefficients. You can watch my video, turn on the translator in your language and there will be no problems with understanding the content of my video. Paragon and Holybro Pixhawk4 - YouTube
At the end of my video you can watch the flight of the aircraft. Pay attention to the operation of the airspeed sensor. As an indicator of flight quality, the aircraft demonstrates a successful flight in AUTO mode.
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Thanks a lot for your reply it confirmed something for us. we used the same pitot but with different sensors and we always arrived at the same value, meaning the size of the dynamic hole is the reason and not the sensor.