Tarot Roll Drift Issue

[steve fh]

Well after several good flights with the Tarot gimbal the dreaded horizon drift issue appear this evening. Seems to be linked to yaw motion. Very frustrating 

anyone had similar issues with other controllers and if so what was the solution ?

[Hands0n]

Could that not be an issue of calibration? Where the gimbal controller thinks it is at a different attitude to the aircraft and its FC? I';m making a weld guess here because I haven';t even set up a gimbal before. But just watching the video clip is very suggestive of that.

Sent from my C6603 using Tapatalk 4

[e.chipev]

I have the same problem..
I guess the gains are not right but I got tired adjusting them for 2 weeks now...
It might be something else (I hope so)...

Desire rc - alexmos controller
Asp gimbal

I haven';t done 6 axis calibration... have you?

[QuadBod]

What platform are you guys flying? At one point this was looking like high-frequency vibration related. I haven';t been following it since I don';t seem to have the same problem (550 carbon quad, 930KV motors).

[steve fh]

I haven';t done 6 axis calibration... have you?

On the Tarot there is no faciity to carry out a calibration.

I';ve just done a load of reading and been through the gain set up procedure as per the Tarot manual. Just flow and the issue is still there but less pronounced.

Sorry to hear you are also having issues but glad it';s not just the Tarot system that suffers.

I';ll be amazed if it';s vibration related as it seems 100% linked to when the machine yaws and i';ve got multiple level anti vibe on the Y6 which is jello free even with out of balance props.

I';m running direct off a 1000mah 3S lipo (not the flight battery) but might try running via a 12v BEC as it will give a more stable voltage.

[steve fh]

What platform are you guys flying? At one point this was looking like high-frequency vibration related. I haven';t been following it since I don';t seem to have the same problem (550 carbon quad, 930KV motors).

Y6   http://www.multi-rotor.co.uk/index.php?topic=3843.0

[QuadBod]

I';ll be amazed if it';s vibration related as it seems 100% linked to when the machine yaws and i';ve got multiple level anti vibe on the Y6 which is jello free even with out of balance props.

I was dubious, but that was the conclusion that was arrived at collectively by a few guys on another forum. Equally, I';d be surprised if it';s configuration related, as there are plenty that work beautifully with the stock configuration. Odd the yours worked okay initially, then started drifting.

[steve fh]

I was dubious, but that was the conclusion that was arrived at collectively by a few guys on another forum. Equally, I';d be surprised if it';s configuration related, as there are plenty that work beautifully with the stock configuration. Odd the yours worked okay initially, then started drifting.

It seems motion linked to Yaw.  This is yesterday evenings flight with tweaked gains and it is consistent in it';s behaviour linked to Yaw.

If I roll it down and up the horizon restores.

[QuadBod]

Oh, yes, definitely Yaw related, sorry, I didn';t mean to suggest that';s not what triggers it. More a question of trying to figure out why some people have a problem with roll-drift on yaw, and others don';t. It sounds like you';ve ruled out vibration, which was one suggestion I';d read. Must be very frustrating if you';re affected by it.

[steve fh]

I';m wondering if it';s linked to the mounting point. Mine is directly on the centre of the machine at the CoG.  I';ve have load rails on the way to try it out in front

[QuadBod]

Interesting, mine is out front. If the rain ever stops I';ll mid-mount it and see if I can induce the problem.

[QuadBod]

Okay, the rain reduced to a light drizzle, although still quite gusty out, so I moved the Tarot to mid-ship and set sail.

Sorry to report that despite some fairly aggressive yawing (hard left 90 deg, hold, hard right 180 deg, hold, back to centre, hold, etc, as well as a full speed 360 deg pirouette), I couldn';t induce a noticeable roll drift. Which is not to say you shouldn';t try moving yours out front to see if it affects anything, but moving mine to the centre didn';t appear cause the problem.

Since I could see the props and skids though I did gain a new-found respect for just how much the quad gets chucked around in even moderate gust, and how well the T-2D does at compensating for it.

[Marty McFly]

just a quick question,im in the market for a new Gimble +controoler and untill this thread thought the tarrot was very good,in general is it better than the RC Timmers one please,thank you,Marty

[QuadBod]

It is very good - and in terms of out of the box experience, I';d say superb; I';m using stock settings, where as most you have to tweak and tune to get them stable. However a minority have been unfortunate enough to suffer from this yaw induced roll-drift. It seems to affect other gimbals besides Tarot though, so you either have the problem or you don';t.

I don';t think it';s any more common with the Tarot, there are just more Tarots out there than any other individual brand, so you';re more likely to hear of of it with Tarots than say the RC Timer.

All anecdotal, and my personal opinion of course, and I may be biased by not having a problem gimbal, but I';d say go for it.

[steve fh]

For pug and play it';s ok. However the horizon issue I have is making it good as useless for any sort of quality footage.

I';m about to order a third party controller and gyro so I can convert it to run Nul Code to try ad resolve the issue.

[QuadBod]

Okay, the rain reduced to a light drizzle, although still quite gusty out, so I moved the Tarot to mid-ship and set sail.
Sorry to report that despite some fairly aggressive yawing [...] I couldn';t induce a noticeable roll drift.

I';m about to order a third party controller and gyro so I can convert it to run Nul Code to try ad resolve the issue.

No thanks necessary... 

[steve fh]

I';ve made few gain changes inducing dramatically reducing the Integral Gain on the roll.

It';s better but not perfect

[QuadBod]

I think the problem may be your location.

Apparently you live in a country where it';s considered okay to overfly members of the public (including a mother pushing a baby in a pram with her child in tow) with an inverted weed whacker.

[teslahed]

Apparently you live in a country where it';s considered okay to overfly members of the public (including a mother pushing a baby in a pram with her child in tow) with an inverted weed whacker.

Unfortunately i have to agree here. Flying a hexacopter over members of the public in a park like this is quite a risky and irresponsible thing to do. Any hexacopter big enough to carry a brushless gimbal is also big enough to do some serious damage if it did manage to crash into someone. There are so many potential causes of catastrophic failure on even the best made multirotor that you can';t be sure your hexacopter isn';t going to cause a serious incident one day if you keep flying it like this.

You can';t fly in a public field like that and expect to be safe. Please reconsider the amount of space you give people.

[steve fh]

Having viewed the clip in the clip in the cold light day yesterday morning I have to say I';m in complete agreement with you both.

Some how I';ve gone from only ever conducting brief tests there when there is no one about to that. Serious lack of judgement and off for a serious word with my self.

[teslahed]

Serious lack of judgement and off for a serious word with my self.

None of use are borne knowing this stuff. I';ve made a few errors of judgement myself with things like this in the past. I managed to fly into a lamp post once with a mini FPV quadcopter during testing - i really should have been flying in a big field but i had flown line of sight in that area before and thought i';d be fine FPV (i was impatient). Lesson learned the easy way (i just damaged the quad) 

You flying skills and multirotor look perfectly fine to me - it';s just a question of that tiny possibility of something going horribly wrong, which might not be your fault when it does. I';ve seen my quad randomly flip and fall out of the sky once or twice in the past for no obvious reason where i had zero control or ability to recover or even aim the multirotor on the way down. If there had been lots of people in the field at the time it would just have been a question of chance as to whether i hurt someone or not.

It';s easy to go from small hops to full scale flights without realising. I guess that makes you a real multirotor flier now

[steve fh]

It';s easy to go from small hops to full scale flights without realising.

Too right Chris. I used to never do anything more out there than a brief close range hover to mess with Naza gains when it was deserted.