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Compass calibration alternative

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For the compass calibration we spin the micro-copter around in two different directions in order that the 3 directions (dimensions) of the compass can detect the strongest magnetic field to know direction of north.

The calibration steps with spinning the micro-copter are VERY DIFFICULT with a large and heavy octo-copter.

I see that also for the large and heavy MK3500 the same method is to be used. I do not know how this copter can be calibrated by a single person. Is it possible?

I am looking for a better way to calibrate compass. Holding the copter vertical and turning myself would be much easier. My idea: Following the photos of calibration process, in step 2a the copter is normally held horizontal and copter is spun around arm 2 and 4. Instead I would hold the copter vertical in arm 4 and turn around my own axle. In step 2b I would hold the copter vertical in arm 1 and again turn around my own axle. Step 4 would be a repeat of step 2. This should provide similar north-south changes to the compass as normal method, but compass dimension should be interpreted different.

@HolgerB:
This method does not work with the current software ( 2.18 ) but would it be possible to make a new compass calibration method like this?
« Bearbeitet von Foersom am 28.04.2017 13:13. »
Entwickler, Admin
Registriert seit: Feb 2006
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During calibration it is important that all magnet sensors "see" the maximum and the minimum of the magnetic field.
It is not nessecary to rotate the entire copter.
But in the european area we have a magnetic inclination of 60°. That means, that you need to tilt the copter at least 60° for each axis.

If you want to rotate the MK vertically, the MK doesn't measure tha max and min values.
But the calibration is in the open part of the NC and you could change the code on your own. Basically you just need to extend the magnetic vectors by a trigonometric function.
http://svn.mikrokopter.de/websvn/filedetails.php?repname=NaviCtrl&path=%2Ftags%2FV2.18a%2Fncmag.c

Regards,
Holger
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HolgerB meinte
During calibration it is important that all magnet sensors "see" the maximum and the minimum of the magnetic field.
It is not nessecary to rotate the entire copter.
But in the european area we have a magnetic inclination of 60°. That means, that you need to tilt the copter at least 60° for each axis.

Thank for the explanation. I understand now that during calibration the compass chip has to measure the max/min magnetic field value accounting for inclination, not just max/min horizontal value. I will have a look on the software later.

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