Leg compass alternative ?

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I have replaced a leg compass on two of my birds, one would not fly straight (this was a recently acquired second hand bird) the other bird had done 30 flights and all of sudden compass error that would not calibrate.

With parts getting harder to get, especially here in Australia, is there an alternative to the leg compass or a part you can fit to the leg ?

I would like to buy a couple of spares but as I cannot find any in Australia I am keen to find an alternative. My birds are running dev 3.7 except one, its on open solo 3.

Appreciate any help or suggestions thank you in advance
 
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Hi @Robpower maybe my solution will work for you to.

last time, after mine disaster, Compass Error kicked in and went through calibration, the green line didn't went to end, so I couldn't calibrate it at all.
today went out to test again. after powering on, again Compass Error, but this time going through calibration, the green line goes till the end, and I got warning - Calibration Failed. tried some 10x, all the same - Calibration Failed

After that last disaster, I searched the www to find out what could cause it and how to resolve.
Actually, there are 2 compasses, one in the leg and one in the same Solo beneath extension bay (I assume in Pixawk cube - so magnetic interference and other errors kick in when placing metal or electronics to close there)
The primary and default compass (as I understand) is that in the leg, compass in Solo - 2nd

In Mission Planner and Solex you can disable either of those.
I was without NB outside, so in Solex parameters searched for COMPAS... last three parameters are for COMPAS1 =1, COMPAS2=1, COMPAS3=0 (1-enabled, 0- disabled).
Changed COMPAS2 parameter to 0 and Sent update.

Immediately Compass Error disappeared from controller.
I restarted both - drone and controller. No Compass Error anymore. Checked again in Solex parameters if COMPAS2 is disabled (it was).
To be sure, I did Compass Calibration and it did perfectly.
Then took drone in the air - everything OK.

So, maybe your leg compass are not the problem, but the internal one.
Please check and inform back

p.s. from Solo total disassembly, mine GPS parameters went up (maybe connector was not pressed fully or something other), now getting 19-23 satellites, 0.5-0.6 HDOP :cool:
 
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Hi @Robpower maybe my solution will work for you to.

last time, after mine disaster, Compass Error kicked in and went through calibration, the green line didn't went to end, so I couldn't calibrate it at all.
today went out to test again. after powering on, again Compass Error, but this time going through calibration, the green line goes till the end, and I got warning - Calibration Failed. tried some 10x, all the same - Calibration Failed

After that last disaster, I searched the www to find out what could cause it and how to resolve.
Actually, there are 2 compasses, one in the leg and one in the same Solo beneath extension bay (I assume in Pixawk cube - so magnetic interference and other errors kick in when placing metal or electronics to close there)
The primary and default compass (as I understand) is that in the leg, compass in Solo - 2nd

In Mission Planner and Solex you can disable either of those.
I was without NB outside, so in Solex parameters searched for COMPAS... last three parameters are for COMPAS1 =1, COMPAS2=1, COMPAS3=0 (1-enabled, 0- disabled).
Changed COMPAS2 parameter to 0 and Sent update.

Immediately Compass Error disappeared from controller.
I restarted both - drone and controller. No Compass Error anymore. Checked again in Solex parameters if COMPAS2 is disabled (it was).
To be sure, I did Compass Calibration and it did perfectly.
Then took drone in the air - everything OK.

So, maybe your leg compass are not the problem, but the internal one.
Please check and inform back

p.s. from Solo total disassembly, mine GPS parameters went up (maybe connector was not pressed fully or something other), now getting 19-23 satellites, 0.5-0.6 HDOP :cool:


Hi @makatanav

Thank you for your reply, I did actually do what you said in your post , that's how I found out the leg compass was bad. I had this problem way back with my first solo, and did what you suggested and it cleared the error but I have never flown with only one compass, I didn't think you could do that.

I put a new leg compass on and all good, I just wanted to get a spare one for future, I have collected up a few spare parts for my fleet as parts will get harder to get.

I did read a post on degaussing, might give it a go, I have two legs here in a box that are no good, not sure it will work but nothing to loose. Here is the post I read:

"Easy fix that works. Degauss the compass! Coil up about 20 feet of 24 gauge wire in a coil about 4 inches in diameter and connect it to a 6 volt AC output of a wall wart. Make sure it is AC, DC will not work. Now energize the coil, place the coil around the compass leg on the solo and slowly remove the coil. Turn on Solo and behold..no magnetic interference problem. You may have to do this a few times depending on how much the compass sensor has be magnetized. I had the same problem, no matter where I put the Solo, the readout on the transmitter had the display " Magnetic Interference", after the degaussing everything works fine."


Nice to see the improvement in satellites, which GPs do you have, I use the MRobotics one in all my birds.
 
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I had this problem way back with my first solo, and did what you suggested and it cleared the error but I have never flown with only one compass, I didn't think you could do that.

Nice to see the improvement in satellites, which GPs do you have, I use the MRobotics one in all my birds.
On the 3DR Solo with LiIon 9000mAh battery | up to 30min flight time guy was saying that he disabled internal compasss and is flying with no problems. I red also somewhere, that due software limitation some time ago it was no possible to disable, now it is possible.

mRo GPS u-Blox Neo-M8N also in mine.

Interested if the coil thing will be working 👍
 
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jxo

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I also had compass Mag Interference issues that ultimately were due to a bad leg compass. f you can find one, the old HERE GPS module has an integrated compass that can replace the leg compass. I also made several flights with the leg compass disconnected with no obvious problems.
 
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Here GPS sell on e-bay for $50.00 three on there now for that. I have bought two for $40.00 . They have worked fine.
 
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I know it's a year later but normally the cable breaks at the PCB and resoldering solves the problem.
 

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