Tricopter unstable / Can't get good footage

[Craftydan]

Steveis's V1.18S1 Pro appears to be the latest, and should be available in the kkmultikopter flash tool's repository. His latest "lite" version is 1.17S1 lite, but the primary difference is fewer settings and options available.

If you feel comfortable with leaving that-intriguing-switch-over-there alone until you know what it does, then pro is just fine. Otherwise, you can remove that temptation/confusion by going with the lite.

 

[Fern-Fox]

Does the lite have the switch for auto level on/off?

 

[Craftydan]

They all do pretty much.

 

[Fern-Fox]

Ok I flashed it with V1.18S1 Pro and heres how she flies (Mostly defaults, just tweaked very few settings)

Still a bit shakey and this footage would be unusable for any videos.. but for the maiden its pretty good. So how do I go about tuning it?

Also, that footage was done with a 4000mah, Ill try with a 2200mah tommorow, might be a bit more stable.

 

[Craftydan]

Looks like a great maiden flight

A good guide for tuning the gains can be found starting on pp. 5 of the old kk2 manual:

http://www.hobbyking.com/hobbyking/store/uploads/181270330X7478X47.pdf

Sounded like there was a little bit of jitter in the throttle -- the gains should clean that up. Otherwise, it should become more controllable . . . which means better video comes from better control. You've seen the air-to-air video tips episode right?

 

[Fern-Fox]

Thanks

So, I used those two tutorials and some others I found on YouTube and I've found my p-gain sweet spot (85-90)
But I still have these problems:

• It gets thrown around by wind (very hard to control in wind)
• It yaws around by itself, it seems as though the yaw starts to drift in one direction
• Altitude is hard to control, I give it 1/2 it sinks, I give it 7/10 and it shoots up, I give it 6/10 to counter it and it shoots down, it's just really hard to manage my throttle.

P/I gains:

P gain: 85
P limit: 100

I gain: 0
I limit: 20

I've tried adjusting my I gain but it makes it even harder to control my height

Any help?

 

[Fern-Fox]

Any help? ^

 

[Craftydan]

- Stay out of the wind. Not forever, but tuning the board and learning throttle managment isn't trivial, and wind makes things worse. If you're leanring, wind *always* makes things more compicated.

- The "I" on the board is the *only* thing that will counter drifting angle in acro -- without it you are manually balancing the frame on a beachball, while trying to keep it from moving laterally . . . if the frame can't stay at the angle you put it, you'll always end up chasing the whims of the craft instead of sending it where you want it to go. Set it to 1/2 P and if it's not wobbling, leave it there.

- Turn down your Throttle stick scaling. right now if you go to 70% it climbs . . . wouldn't it be nice if that 70% were spread over more of the stick's throw? reducing the stick scaling will do just that. you *don't* want this forever, but until you've learned how to manage your throttle, you need to spread that stick out to amke the "sweet spot" wider.

- Most importantly . . . learn to fly. I know that's what you're trying to do, but seriously this isn't a setup issue. Managing a throttle on a rotorcraft can be mind-bending: Throttle doesn't control your vertical speed NEARLY as much as it controls your vertical acceleration.

Lets say you've got a spot on the throttle -- the "sweet spot" that when it hovers the throttle is there . . . but settign your throttle there doesn't guarentee a hover. Say you're descending, rasing the throttle to the sweet spot will not make it instantly hover . . . the craft is still carying momentum. You've got to first cancel the momentum by going past the sweet spot and as the last of the momentum bleeds off, you ease back to the sweet spot.

The critical part of this . . . you have to stay ahead of the craft's momentum and position in your controls by stopping before it shifts the other way. This takes time to learn and practice, which is why most people spend **SOO** much mind-numbingly boring time practicing hovering. While they're learning the controls and balanceing the craft, they're also practicing managing the throttle. (BTW, if your craft isn't level, or spends most of it's time rocking back and forth, the sweet spot isn't in the same place . . . becasue it'll take more thrust to stay up).

Keep at it. Adjust the throttle scaling to make it a little easier, but you will get the hang of it.

 

[Fern-Fox]

Yes!!! I finally got it! It flies great now! Totally controllable. My only problem is its not 100% stable, does that just mean I gotta not fly in wind for stable video? Or is there any tuning I can do or training?
Ill make a video of it flying, she flies great with auto-level off, I can almost get it into a hover like its in GPS hold
I adjusted my stick scaling on my throttle to 70, but now it takes off at 90%, so I brought it back up to 100, how do I get it to take off at %50?

Thanks a bunch for the help, you rock man

Also: one more thing, my COG was off by a couple inches, I got it almost completely center, that really helped alot.