[Filippo94]

I just did, and it works, the servos react correctly, not shaking. It means even this very little vibration that the mechanic causes is not something the CC3D can tollerate?

[daveapplemotors]

The main gear in you video sounded rough.

Also, perhaps the tail boom needs grounding. I have heard of that.

[Filippo94]

I have a bit of wobble on the tail drive gear, but I've read it's normal non-so-much-precise helis. Will try to reduce it.
Grounding the tail boom? You mean that it's causing a shortcut?

Edit: It's less than this one, I'd say slightly more than half than that. (I found out how to post videos!!)

[daveapplemotors]

Yes, that tail gear is terrible. I bet that a good gear fixes you up.

And, I have heard that a tail boom ground helps keep static electricity from becoming a problem.

[Filippo94]

Isn't there a way to raise the gyro noise tollerancy lowering the stabilization efficiency? I saw online helis with worse oscillations being able to fly pretty well, honestly it leaves me surprised to see I can't even put blades on because of resonance...

Edit: Found it, let's see if tuning it allows at least to have a working setup to test with.

Edit: Of course it didn't solve the issue...

[Filippo94]

I'm going to order again another spare batch for this heli. What to do if the new gear is not as straight as I need, or if it's not going to reduce the vibrations enough?

[daveapplemotors]

Don't worry. It will be hard to find another gear that bad. Will a T-REX gear fit?

[Filippo94]

I think so, the Tarot 450 has most of components compatible. this specific gear has a bit of difficulty passing through the main frame, the other one seems a bit thicker, in the worst situation I'd just have to remove one side of the frame. Only thing that bothers me is that here in Italy there are really few Align stores, and often they have not all the things needed, so I have to wait them to come here from England....

And in meantime I can not keep troubleshooting, since if the tail gear goes not in place, I can not check for other vibrations, or components needing replacement (another 10 days of waiting). One thing is for sure, I'll never buy again 2nd hand products at this level, for the "toys" in my signature it's not a big issue, these machines can get much worse than I thought instead...

[Filippo94]

I discovered a shop which had everything I needed, today the new gear arrived, it's much more straight, close to perfect, and with also a different tape under the CC3D, most of the issues seem gone. I'll try now to balance the tail blades, and then the main blades again, hoping to see no oscillation from the CC3D  .

I've also noticed that if I don't lock the heli, the vibrations on the servo are much lower compared to when it's locked. Maybe the support on which it is mounted amplifies the vibrations? Where should I clamp it to test?

[Filippo94]

I'm really starting to wonder if it's better to trash the whole project.
I've balanced the blades multiple times, checked everything that could cause vibrations and tried to fix as much as I can, Still without blades I get a slight resonance that I can see only through the correction of the CC3D, and with the blades I get really dangerous wobbles close to 50% throttle and after, if the heli was not clamped to the table it would have exploded touching the ground in a few seconds. Tracking is just perfect, I can't distingue the two blades looking at them on a side at low RPM. This board is just ridicously sensible to any kind of noise, and at this point seems the only thing preventing me from flying the heli.

[Filippo94]

Looks like the vibrations now are low enough to use the filters, when the wind will calm down will finally try to fly it. Right now it still tends to tip over at take off. I need a proper space where to fly it, where I can give it a good push to raise it in the air, instead of being scared to give pitch in this little area...

[Filippo94]

Today the heli had finally a maiden flight!

Accelerometers are responding well, but gyros (tail's more visible/investigated) are really really sloppy. I tried raising the P to as high as I could without oscillations, but the tail keeps being quite oscillating when giving input/stopping it. If I raise it more it starts oscillating. I have some play in the tail I have to get rid of, but the behaviour of the tail seems not correct to me.

I surely have to do further tests, and tweaks, but right now, do you have any tip on how to solve it?

Ah, this is in rate mode, with heading lock it seems to always want to correct user's input, maybe it is indeed trying to keep heading direction like if it had a compass?

I tried to place the heli on a flat surface and to compensate the inclination of the CC3D in the attitude panel (due to irregular bottom, the board is not perfectly level on the stick sponge tape). Though with Attitude mode the heli as a visible drift. Is there a more effective way to zero out the inclination of the board, or is it better to just not try to compensate it? Also, is there a way to change the Attitude's inclination target? Helis tend to not be deadly horizontal to have a stationary hover, due to the tail rotor generating a lateral force. A solution is to  keep the heli a bit tilted (usually to the right). Is that possible to be accomplished, without having to make the board think it is not level?

Here's the UAV file (the middle flight mode is just for vibration tests, it has its own switch)

[daveapplemotors]

Horrray! A maiden flight!

Don't worry about fixing the tail slop mechanically. I have two HKs that have 10-15 degrees slop. The tails are great. That is what PID is all about, que no? I don't have fast servos either. My friend's Trex 250 with the really, really tight tail linkage does NOT fly better.

Don't worry about "board perfectly level" If you fly in Attitude or Rattitude then it may becomes important.

I see you have one mode set for Rate Trainer. How is that?

I fly in only Rate , Rate, AxisLock for tuning. I try Bank 3 first. It has the highest PID numbers that might cause some oscillation. I can switch back to Bank 1 in flight with one easy switch if it gets squirrelly. If I try Bank2 I can switch back to Bank 1 from there very easily, also. Bank 1 has the lowest numbers but if I like the way Bank 3 flies I make it the new Bank 1 and adjust Bank 2 higher and Bank 3 higher still. Repeat. If Bank 3 flies good save time and don't try Bank 1 or bank 2. Swap Bank 3 into Bank 1 and raise the values until you see oscillation on each axis.

Also I adjust Yaw neutral value until it hovers 'hands-off".

Try that with yours. You can get close to good PID numbers faster that way. Too bad we have only 3 settings Banks...
Look at my PIDs . My I values are just over 50% P.

Today I ran a few packs through Amarillo doing just that. It is really good. I like it. I may experiment with Rattitude, Attitude, Vbar and Acro+ on Amarillo  just to learn how they feel after I get the other one, Blackie, doing something  autonomously.

BTW if you got 5 TX modes I bet you can do 6. Adjust endpoints of both inputs to fine tune.

[Filippo94]

Yes, I can get 6, this is the topic where I explain it: https://forum.librepilot.org/index.php?topic=1413.0

Thanks for the tail slop, that'll save me some moneys

I do fly Attitude at the moment, it helps me controlling the heli while I do tweaks, as right now the heli responds in a quite unprecise way, this helps me keeping a referement while flying. When will be finished, I'll switch to rate, and start tuning that, knowing that if things get wrong Attitude works and can save my heli. Will just eyeball the tilt of the board based on the result of the attitude zero position while flying, like they are trims. Right now with stick at zero position the heli drifts quite fast back and left. The way I adjusted it right now is placing the heli on a horizontal surface, and looking at the telemetry setting numbers untill the board thought to be level. Clearly this "scentific" method did not work, so I'll go for the good old Try and error

I've set 4 flight modes, just thinking a way to use more flight modes, I have Attitude and Rate Trainer as a switch combined with "up" position of one other switch, and Rattitude and Rate as the results of the first switch combined with "down" position of the other switch. Just like having an aggressivity switch . Since they're close together, it needs my finger to just switch up both to fastly jump into "panic mode" activating Attitude. Right now I can not trust Rate too much, since the gyros still need tuning.

I also discovered the heli had no power enough to keep the tail straight (giving max right yaw barely moved the heli on the right), I figured out the tail servo neutral position was to be set not centered. This should be specified though, it's.... the third time, a "center" position has not to be in the center, this is starting to get quite confusing honestly.

I keep the 5th flight mode as manual, just to check the vibrations of the heli when I swap blades, or just want to be sure about resonances. once my tuning session is over, I'll remove that from my TX, so I will not activate it on accident, yet I can reuse it without having to get back to the netbook.

Thanks for the banks suggestions, I just assumed they all were the same, will try like you said.

[Filippo94]

So, this sunday was my 2nd day of flying the heli, this week I did absolutely nothing.

Unfortunately had not the possibility to record a video, but I finally discharged my first lipo in one go .
Was a pure joy, incredibly stable, even though it had yet some oscillations, and a such cheap hardware to fly with.

So, the banks showed to me the same exactly settings between each other (of course the first one had my settings). Today I worked on setting Attitude to be as reliable as possible, and same for the tail. So far I came out with a pretty solid tail, which doesn't hold the position with pitch pumps though, I'll have to do further investigations. Rate was the tail setting.

Attitude has a strange behaviour instead. I managed to get a correct "center" to hover the heli, the cyclic response is pretty snappy, up to oscillating if I esagerate, but even so the speed with which it returns to self level target is pretty slow, seems like not having it at all when attempting fast flights. It does center, but takes a few seconds even from a slight bank angle. Seems also to slowly oscillate a bit around the center, like a ball rolling toward the bottom of a bowl. Is there any way to get a faster "centering speed"? Raising P causes it to oscillate even more when I suddently change bank angle. I really like it though, makes flying really interesting compared to what I expected from it.

Rate works, but has not been tweaked, I just checked it responds good enough to handle the heli.

I also managed to lower the noise filter for the gyros, but I saw that the adviced max value for noise is 0.02, I have it around 0.05, was at 0.15 to get rid of resonances on the bench tests ...

Next things to do: try and check HeadingLock for Tail, get a snappier response from Attitude, configure Rate, getting rid of the various oscillations that occour on the tail at different flight speeds.

I'll keep attaching my progresses on the settings, so who is interested in checking it maybe has something to learn. BE CAREFUL, I'm not an example of who knows everything