Close..: keep the drone still and do three cartwheels ... while holding drone in left arm then in right arm. LOL
True North or Magnetic North?
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There has been a lot of discussion about the necessity of Accelerometer calibration and Compass calibration on the H480.
I think all agree that the compass being magnetic gets aligned with local magnetic north (aligning the compass with your local magnetic declination). How often that needs to be done, or how far you move in any N/S or E/W direction before needing to recalibrate also seems to be a matter of personal preference (although if you are still under warranty following the manufacturers guidelines would be highly recommended).
As for the accelerometer calibration (static) there is an opinion that they are calibrated during the initialization routines. That may be correct, but I think they are just checked for functionality and send the system information about the position that the H480 is in compared to the stored calibration values. The only way to know for sure either way is through confirmation by Yuneec engineers/technicians that have access to that information.
I believe the true north and level surface for the static accelerometer calibration since I’m sure they are contained in the IMU for the H480. My experience working with Avionics and calibrating and testing IMU’s, we did align the units where the way they mount in the aircraft would have the longitudinal axis of the aircraft aligned with True North and on a level so the rotational axis is aligned with gravity. The calibration procedure recorded the biases of the accelerometers in the IMU’s against known values for the latitude, longitude, and elevation the calibration was being performed at.
I don’t have access to more detailed information from Yuneec even though I have requested it on several occasions. I have done the static accelerometer calibration once according to the instructions in the extended manual and the compass calibration twice. One compass calibration in Michigan to practice the procedure and the second in Florida in an open area away from as much interference as I could manage.
So far so good for me. My TH Pro flies steady and has not given me any cause for concern to this point and I only hope it stays that way. I hope that how you care for and maintain your aircraft keeps yours working in top form and condition.
I think all agree that the compass being magnetic gets aligned with local magnetic north (aligning the compass with your local magnetic declination). How often that needs to be done, or how far you move in any N/S or E/W direction before needing to recalibrate also seems to be a matter of personal preference (although if you are still under warranty following the manufacturers guidelines would be highly recommended).
As for the accelerometer calibration (static) there is an opinion that they are calibrated during the initialization routines. That may be correct, but I think they are just checked for functionality and send the system information about the position that the H480 is in compared to the stored calibration values. The only way to know for sure either way is through confirmation by Yuneec engineers/technicians that have access to that information.
I believe the true north and level surface for the static accelerometer calibration since I’m sure they are contained in the IMU for the H480. My experience working with Avionics and calibrating and testing IMU’s, we did align the units where the way they mount in the aircraft would have the longitudinal axis of the aircraft aligned with True North and on a level so the rotational axis is aligned with gravity. The calibration procedure recorded the biases of the accelerometers in the IMU’s against known values for the latitude, longitude, and elevation the calibration was being performed at.
I don’t have access to more detailed information from Yuneec even though I have requested it on several occasions. I have done the static accelerometer calibration once according to the instructions in the extended manual and the compass calibration twice. One compass calibration in Michigan to practice the procedure and the second in Florida in an open area away from as much interference as I could manage.
So far so good for me. My TH Pro flies steady and has not given me any cause for concern to this point and I only hope it stays that way. I hope that how you care for and maintain your aircraft keeps yours working in top form and condition.
Phaedrus
Premium Pilot
I don't have evidence. But a typical IMU unit contains Gyroscopes, Accelerometers, and Magnetometers. Direction probably doesn't matter much to accelerometer, but it sure sounds like it would matter to Gyroscope and magnetometer. Bear In mind "Accelerometer Calibration" is just a phrase translated from Chinese for whatever the process is actually doing. For all I know, the correct translation might have been "IMU calibration".
I think I will fail on the conservative side and pay attention to the direction from now on.
(Hope I don't need my mirror again.)
I think I will fail on the conservative side and pay attention to the direction from now on.
(Hope I don't need my mirror again.)
Every direction but one. DOWN is north. At least that's what your compass would tell you if you stand it on edge.
If it weren’t for bad luck, I’d have no luck at all. Gloom and despair.
PatR
Premium Pilot
Bonjour, Je n'ai pas lu tous les messages qui précède, mais de la mémoire, l'étalonnage de la boussole et du gyroscope est une remise à zéro important de faire les 3 autour des sorties, il maintient le drone stable en vol et un RTH parfait sans mauvaise surprise backd, orienter le nord face drone est inutile ..
Après les 2 nords, parce qu'il ya 2:
_la nord boussole / boussole, il est magnétique.
_ La carte nord / nord géographique, il indique aussi le nord , mais avec un réel changement à prendre en compte.
différence entre les 2 nords de plus de 50klm.
Ceci est appelé déclinaison magnétique.
Après les 2 nords, parce qu'il ya 2:
_la nord boussole / boussole, il est magnétique.
_ La carte nord / nord géographique, il indique aussi le nord , mais avec un réel changement à prendre en compte.
différence entre les 2 nords de plus de 50klm.
Ceci est appelé déclinaison magnétique.
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Translated; from French to English
Hello, I have not read all the above messages, but from memory, the calibration of the compass and the gyroscope is a significant reset to make the 3 around the outputs, it keeps the drone stable in flight and a perfect RTH without a bad surprise backd, to orient the north face drone is useless ..
After the 2 nords, because there are 2:
_the north compass / compass, it is magnetic.
_ The map north / north geographic, it also indicates the north, but with a real change to take into account.
difference between the 2 nords of more than 50klm.
This is called magnetic declination.
rdonson
Premium Pilot
Phaedrus
Premium Pilot
Just for grins, the last time I drove from Eureka to Orange County, 700 miles apart, I did not bother to re-calibrate the compass.
I did this as a test.
OC is +11 deg 41 min (+11.6883)
Eureka is +14 deg 17 min (+14.28333)
That is only a 2.60 degree difference but combined with the distance many would feel the need to recalibrate the compass.
I observed no difference in the flight performance, positioning accuracy, or any other issues between the 2 areas.
This is with an H+ with Build 822/829
This site allows you get your declination (variation) accurately:
This site allows easy conversion:
www.rapidtables.com
I did this as a test.
OC is +11 deg 41 min (+11.6883)
Eureka is +14 deg 17 min (+14.28333)
That is only a 2.60 degree difference but combined with the distance many would feel the need to recalibrate the compass.
I observed no difference in the flight performance, positioning accuracy, or any other issues between the 2 areas.
This is with an H+ with Build 822/829
This site allows you get your declination (variation) accurately:
Magnetic Declination on Map
Click on the map to find the magnetic declination at your location
www.magnetic-declination.com
This site allows easy conversion:
Degrees,minutes,seconds to decimal degrees converter
Degrees (°), minutes ('), seconds ('') to decimal degrees angle converter and how to convert.
Phaedrus
Premium Pilot
On other point of nomenclature.
Declination and variation are the same thing. They measure the angular difference at your location between magnetic and true north.
Deviation measures the errors introduced into a magnetic compass from local sources, hunks of metal EM fields, etc.
Declination and variation are the same thing. They measure the angular difference at your location between magnetic and true north.
Deviation measures the errors introduced into a magnetic compass from local sources, hunks of metal EM fields, etc.
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A couple of days ago, I booted up and took off from a sloping surface. The TH immediately straightened itself up to level and flew normally.
