Fixing DJI's Compass Problem

[Fximaging]

Hello Everyone....

I have been selected to participate in the beta program to help fix the compass issues here on this forum. I just thought you might want to know that yesterday, I downgraded my firmware to 1.08 (from 2.0), and my phantom flight is much improved. The j-hook is still there in the first few seconds of flight, but it disapears quickly. My altitude is more consistent, and my spins are much more centered. I have the iosd-mark2 on my phantom, so i am going to record some flights and export them into google maps (i think this is the program) where we should be able to see a graphical view of the flight. I am then going to put firmware 2.0 back on, and do the same thing. My only issue is i installed my iosd inside my phantom, so i dont have access to the usb port. I never planned on using the recording feature, but now..... I am going to try and install an extension cable out and down one leg to make it easy to access. Anyhow, you may want to try downgrading.... It is a major improvement as far as i am concerned.

David

 

[NYRangers99]

Thanks Ianwood…appreciate the info…if i decide to rotate it I will def let you know…still undecided if I wanna mess with it and rise flyaway…just very frustrating thats this is happening..I really hope DJI is working on this problem and hope they get it fixed soon…Was watching some videos with F550 with Naza M..video was from back in 2012 and he was getting TBE at first take off also…but again seemed to settle down after a few minutes, seems its been a problem for a while…here is the video..kind of long but he gets TBE right off the bat
http://youtu.be/mWS9oqBdWOI

 

[NYRangers99]

FXimaging…I agree..I downgraded also, definitely a big improvement over 3.0…3.0 was horrible

 

[ianwood]

Hello Everyone....

I have been selected to participate in the beta program to help fix the compass issues here on this forum. I just thought you might want to know that yesterday, I downgraded my firmware to 1.08 (from 2.0), and my phantom flight is much improved. The j-hook is still there in the first few seconds of flight, but it disapears quickly. My altitude is more consistent, and my spins are much more centered. I have the iosd-mark2 on my phantom, so i am going to record some flights and export them into google maps (i think this is the program) where we should be able to see a graphical view of the flight. I am then going to put firmware 2.0 back on, and do the same thing. My only issue is i installed my iosd inside my phantom, so i dont have access to the usb port. I never planned on using the recording feature, but now..... I am going to try and install an extension cable out and down one leg to make it easy to access. Anyhow, you may want to try downgrading.... It is a major improvement as far as i am concerned.

David

I saw that you posted about it being better back on 1.08. I am curious how that may play into it. There is clearly a non-volatile adaption (resets after each flight) that slowly corrects for the issue. What I don't know is if there is a persistent (remembered between flights) adaption that is somehow also involved but because of the bug works against fixing it. I feel like the hooking has gotten worse for me despite consistent compass mod values. Others have reported the problem developed over time after having the P2 for a while and it was OK in the beginning. Could be that flashing new firmware wipes out the persistent adaption.

Maybe you could see if you notice a progressive worsening on 1.08 before jumping back to 2.0. That would help corroborate a persistent adaption as well as a volatile one.

 

[Fximaging]

I will do that. I intend to fly again tomorrow, and download the flight data. i an going to do multiple forward/backward passes, rotations and hovers. I will be flying several times a day during the next week, and i will retest at the end of the week and record that data as well.

 

[Lenny7118]

If any of you are on facebook. I would suggest you go to DJI's page and bug them about this. If enough of us do this, we might get a response. Link below.

https://www.facebook.com/#!/DJIglobal

I just went on DJI site on Facebook and did not see any mention if this problem. I wrote about it ! Is anyone else going to or just complain , seriously ! If we don't complain to DJI it won't get fixed

 

[phantomguy]

Is this compass problem completely separate from the "Naza M Yaw Drift" problem found on so many google hits?

 

[Lenny7118]

Is this compass problem completely separate from the "Naza M Yaw Drift" problem found on so many google hits?

If your P2 is drifting ( J Hooking ) left or right and not flying in a straight line but drifts than I guess yes. It was narrowed down to the messed up compass on the P2. Someone wrote a long article on the problem and it comes down to the Magnetic Declination. I read about it first on RC groups forum and I think it's reposted on this site.
http://www.google.com/url?sa=t&rct=j&q= ... 2518,d.cWc

 

[landonkk]

Hello Everyone....

I have been selected to participate in the beta program to help fix the compass issues here on this forum. I just thought you might want to know that yesterday, I downgraded my firmware to 1.08 (from 2.0), and my phantom flight is much improved. The j-hook is still there in the first few seconds of flight, but it disapears quickly. My altitude is more consistent, and my spins are much more centered. I have the iosd-mark2 on my phantom, so i am going to record some flights and export them into google maps (i think this is the program) where we should be able to see a graphical view of the flight. I am then going to put firmware 2.0 back on, and do the same thing. My only issue is i installed my iosd inside my phantom, so i dont have access to the usb port. I never planned on using the recording feature, but now..... I am going to try and install an extension cable out and down one leg to make it easy to access. Anyhow, you may want to try downgrading.... It is a major improvement as far as i am concerned.

David

Thanks for the info. Did DJI ask you to downgrade for purposes of their testing, or did you do this yourself? Please keep us apprised of the situation as much as you can - I'm curious to know how they will go about troubleshooting this problem.

I don't remember my P2 hooking like this fresh out of the box but I don't know if that is simply because I was new to it and simply didn't notice or if there is something larger at play (ie. the flashing of new firmware wiping out persistent adaptation that ianwood hypothesized) Did the first batch of P2's come loaded with 1.08?

 

[ianwood]

I just went on DJI site on Facebook and did not see any mention if this problem. I wrote about it ! Is anyone else going to or just complain , seriously ! If we don't complain to DJI it won't get fixed

DJI is actually looking into it. If you read back a page or two you'll see that I outlined a rough plan to draw attention to this if the need arises. But as it stands now DJI is listening. They've sent some of us some equipment to record data that they can then analyze to look into it further. I will keep everyone posted on new developments as they happen. BTW, where are you based? I don't have your location in my list of people who are affected by this.

Is this compass problem completely separate from the "Naza M Yaw Drift" problem found on so many google hits?

I am not familiar with this. Can you point me to a succinct summary. I don't have the bandwidth to sift through so many Google hits. at the moment.

To the beta testers, I think you are free to wire up your OSD Mark II and do some preliminary tests if you like. I haven't put mine in yet. I assume Terry will let us know what the next steps are. We should all aim to at some point in these tests, to coordinate our test procedure to make sure that we are collecting consistent information.

 

[tom3holer]

I have a new P2Z3 to replace my P2Z2 and after upgrading to the latest S/W I did some tests and am cautiously optimistic with the results.
I was seeing all the classic problems, Toilet Bowl, J hooking and not flying in a straight line.

I tried this on the old P2 by offsetting the compass and had marginal results.
This time I offset the compass about double the variation in my area. You offset the compass to the left if toilet bowl is clockwise and visa versa. I offset it about 25-30 deg. After that I did a compass calibration which I had not dome before and this is again with the newest S/W. Then much to my surprise it was operating perfect. Normally when going forward at a good clip if I centered the pitch stick to stop it the Phantom would stop but make a rather J hook to the right and to the left if backing up. Now it just stops and no hook. The toilet bowl effect is also completely gone.

Hope this helps for those that live in areas of high variation.

Tom

 

[ianwood]

I have a new P2Z3 to replace my P2Z2 and after upgrading to the latest S/W I did some tests and am cautiously optimistic with the results.
I was seeing all the classic problems, Toilet Bowl, J hooking and not flying in a straight line.

I tried this on the old P2 by offsetting the compass and had marginal results.
This time I offset the compass about double the variation in my area. You offset the compass to the left if toilet bowl is clockwise and visa versa. I offset it about 25-30 deg. After that I did a compass calibration which I had not dome before and this is again with the newest S/W. Then much to my surprise it was operating perfect. Normally when going forward at a good clip if I centered the pitch stick to stop it the Phantom would stop but make a rather J hook to the right and to the left if backing up. Now it just stops and no hook. The toilet bowl effect is also completely gone.

Hope this helps for those that live in areas of high variation.

Tom. A couple people have been testing this. If you can let us know if you see any hooking in the other direction towards the end of the flight or if it stays straight right up to the end of the flight, that would be helpful. Thx.

 

[jedi88]

After trying to re-set my compass with magnets about a dozen times, I cannot get my mod values below 2000.

Ordered a new compass and will test, I am suffering from toilet bowl syndrome.

 

[obiwan_pierogi]

OK, check this video out.. I rotated the compass approx. 17 degrees clockwise (as view from above), as my copter had a very strong left drift, and suffered from the TBE.. But now I'm wondering if this creates another problem.. It'll be a couple of days until I get my prop replacements, so the shakiness you see on the video is a result from flying with a couple of warped blades, so try to ignore that.. But watch closely... On all my straight runs, you'll see the copter image bob up near the end.. This is the point that I release the toggle switch.. But notice how the copter continues on, after releasing.. Especially, on the long run over the pool towards the building.. It travels at least an extra 30 to 35 feet, before stopping.. Is this normal? Or does the forward movement create an inertia that keeps the copter moving in a straight line, until the gps takes over? I did notice, in spite of my bad props, the copter flew straight ahead, as opposed to skewing to the left, when lined straight up with an object in front.. Also, for the most part, the final drift at the end was slightly to the right.. Before, if I tried this, the copter would drift a good 25, to 30 feet to the left.. even on a short run.. (by the way, a good 10 mph wind was blowing at the time) https://www.youtube.com/watch?v=MS4DhKG ... e=youtu.be

 

[ianwood]

Switch to ATTI and if you can fly straight, your props shouldn't be an issue. I see some right hand hooking in your video. How much of a correction did you apply to the compass? How many minutes into the flight is this video clip? Compare the beginning of the flight to the middle and end and see if you can see any differences. I suspect it'll be straight to start with and then hook right after a couple of minutes.

As for the rising up or lowering down at the end of a forward movement, I think that is a secondary effect of the hooking and TBE. For it to carry on after you let go, that is to be expected to some degree. It all on the delta speed.

 

[obiwan_pierogi]

My copter had a major left drift, even if I only flew 30 feet straight ahead.. it now has a slight right drift, given the amount I've turned it.. The dips at the end, is when I release the toggle.. When you fly straight at high speeds, the front normally tilts down.. When I release the forward toggle, it bobs up.. But then you see the copter carrying on a bit further.. According to a fellow copter owner, his stops on a dime.. So I'm thinking: is this forward movement, a consequence of rotating the compass? The amount of forward movement, is almost equal to the amount of left drift

 

[holoboss]

Thanks for posting this info, I am in Victoria, BC Canada - northwest shore. I experience these problems at random. on one day all is perfect, a joy to fly, I can photograph all I need without issues. and on next flight it goes scary - phantom flies like drunk, making wild circles, and I can't make it fly straight. it is to such extent that I am afraid of causing damage by hitting something in the area. I try to control it, but usually there is 2 to 3 meters lag before I can control it - only to see the copter will go crazy in another direction. Then again - next day all is fine...

 

[holoboss]

If there is going to be a firmware fix for it - can it be separate from other firmware updates please - not to correct the fly restriction zones (I actually will have a job photographing for a small airport! so, if I am blocked - it will make no sense. and I am a big boy over 56 years old, and can decide what is good or bad idea when flying).

I also hope it would not add the OEM battery warning, which is simply not a fair play. I am not updating firmware because of this issue. I should be able to make my own decision as for supplies, not being forced to pay DJI so much more money than other batteries cost. (just saying!)

 

[RockyMtnOutdoors]

Hi Ian, after you mad me aware of this issue today when you commented on my "go-home crash" posting, I decided test my P2 tonight when I got home from work. I have this same TBE as you all have. In fact I have it pretty bad. It gets better as the flight goes on. I tried a compass calibration, it did not fix it. I started to upgrade to version 3.0 of the software, and it the assistant software told me I have a compass error. Should I buy a new compass?

 

[RockyMtnOutdoors]

I just finished upgrading to V 3.0, and holy crap on a cracker!!!!!! :shock: my TBE is super intense now. and forward flight drifts to the left BIG TIME. I hope this issue gets fixed soon