MicroArduCopter, 3" props, Omnibus Nano, Success!

Most of the parts arrived this week and I got a variable temperature soldering iron for Christmas, so having done it once I am pretty much most of the way through not repeating the mistakes I made last time.

I’ve used acrylic conformal coating in the past because you can solder through it easily. Not great for wires though, but maybe nothing is.

I just finished a copter today that I’ve been working on all winter… Supposed to be the final product of all the testing I did w/ other copters over the winter (testing the new kakute mini and all the vibe issues I was having, etc).
This copter has the least vibrations out of any of them… But it has the lean issue very badly. It’s not really flyable w/out GPS signal, because for whatever reason, having GPS makes the lean issue go away for the most part. W/out GPS, it’s pitching forward and leaning to the left more than I can compensate for, after I’m flying for a couple minutes.

I really don’t get it. Vibes are around 5 in the logs. My other kakute mini copter I was working w/ all winter is 15 on average and peaking to 30+. It had the lean issue, but much less than this.

Maybe I’ll try rounding up everyone w/ the issue and see if we can get logs and figure out if there’s anything we can do about it. Marty was recently posting about the issue on his copter and me and a couple other people quickly blamed vibrations. I was completely sure it’s vibrations. On that last copter, as I fixed the vibrations, the lean issue did get better. But now I’m not sure again. I don’t think it’s possible to get them lower than they are. so frustrating.

I got the ts100 portable temperature controlled iron to put in my backpack for repairs while I’m out. But it’s really great! I use it for almost everything now… other than when I need a very hot iron.

Hi Alberto
Sorry if I repeat myself:
Are you using rubber grommet to dump the FC?
Are you using foam to cover the baro?
Next step dynamic notch to filter vibrations.

Hi Andrea, obviously yes!
I used the ones supplied with the nano v6 omnibus and rubber ring on the nylon stand off. Double foam on the barometer. I thought a 3 “was less critical than a 2”.
I’m waiting for the usual, I think they are indispensable on any nano copter

I have a question about these parameters, that i have setting in this way on my 2" quad and 3" quad:


I can’t find anything on threads about defalut param on sub 250

What the right setting for 3" quad?

Thanks :slight_smile:

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Auto Tune came up with ~ 37xxxx (P_MAX & R_MAX) for a 3"

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On my 3" quad with 1104 5400KV motors and 2S battery I have:

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I set them to 0 - which means basically go as fast as you can. On big copters this is a bad idea because you can overload the motors but on small copters I don’t think there is much of a downside. Autotune will set these base on the fastest response it sees from the vehicle when twitching.


Ok … Thanks a lot.
Now the problem is flow hold with CX OF optical sensor. In final part of this video the quad have fast oscillation like wrong PID.
has anyone had the same problems?

Can you get a log? It would easier to tell which axis is the problem - otherwise looks like D-term feedback to me, so reduce your D-term by 1/2 on each axis and see if that helps.

Yes :slight_smile:

In stabilize and alt hold now flies well, but the problem is only in flowhold mode with optical sensor

I don’t really understand flowhold, but you appear to have a lot of noise on the sensor:

What are your flowhold settings? I would try more aggressively filtering (i.e. reduce FHLD_FILT_HZ), but I am not sure how a small copter would respond to those kinds of changes.

Thanks Andy, my flow hold setting is default like wiki, and i force to 3 EK2_GPS_TYPE.

EK2_GPS_TYPE = 3 to force the EKF to only use the optical flow sensor and not use the GPS

Good news!! with FHLD_FILT_HZ 2
it flies almost well with few oscillates!!
Can I go down to less than 2?

There are some P & D terms for FHLD you could also try reducing those instead

Thanks, do you remember which are?



Hi all,
have you seen this great job?
Are the parameters that come out correct for our little 3 "quadcopters?

Yes, that guide is great! I think his limits on the graphs are for 5" props, but you can interpolate down to 3"… I haven’t tuned from scratch in quite a while, but reading through the guide, I think it covers everything.

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