V-Bar assistance

[th3tick]

Please feel free to send me over to the VStabi forum if that's a better idea, but I thought these were so very basic, I'd just go ahead and stick to old reliable ;)

I got my Logo 500 out today, and started doing some more testing, but two things came up that I haven't experienced before on it. I probably just missed them, but anyway...

Elevator is sharp, but when I just dead release it back to neutral, it sort of bounces back. I figured this was the "strikes back" bit in the setup, and bumped that by 3 (little, if any effect), then 5, then 9, and it still appears to be doing it.

If I punch the collective a bit, it seems to jerk the tail to the left (tail-in). Is this compensated for by Tail Torque Compensation's Collective setting, and I just need to increase it?

It's about 40 degrees here and I wasn't sure if it might be a temp issue, or an idiocy issue, but here I sit. I also just recently put on the AOF, so I suppose the elevator issue could have something to do with that instead. Settings for it are defaults (5/65).

John

[BruceW]

How did your cyclic feel after changing speed and range from the last conversation?

[th3tick]

It's improved, but still needs work. I originally went with 30% expo, but bumped that up to 40% before I started in on these. I left the ATVs at 80%, but have lowered the aileron and elevator cyclic speed quite low (-8 on both, I think), but it's still extremely fast in doing both.

There's a point at which I almost wondered if the changes I've been making have much of any effect.

I flew it back-to-back with my T-Rex 500, and I think that didn't help. There are a number of odd little behaviors I need to fix with the Logo/V-Bar. Agility, however, ain't one of 'em!

John

[th3tick]

Attached is my VStabi file that's giving me troubles.

Side question: which Live mode values matches to which bank? I have three values which come up: one large negative, one almost 0, and one large positive. I just can't figure for sure which one bank 0 goes to - negative or positive.

Thanks,
John

[BruceW]

I noticed that your text file is named trex500.txt. Are you using that for your Logo500?

[th3tick]

Yeah, that should be Logo500. Let me tweak the name. :arggg:

[Flybar-less]

I figured out the bank switching with the live screen. Set bank to 0,1,2,3 on the overview page and it will tell you which bank is selected.

[www.vstabi.de]

Hello John,

this is Rainer from the VStabi.de forum.

Please attach your actual setup here as a file, i will have a look about the values.

[www.vstabi.de]

Uuuhhhh .... there will be a lot of things to improve ...

- check the swash servo mid position (testmode, swash levelled), trim values are very high
- At cyclic use this values for 1st test: Proportional = 35, Hiller = 20, Bell = 80, Paddle steering itenstiy = 47
- AOF off. AOF only needed wit P > 40 at elevator.
- Cyclic gyro deadbands decrease to 5, rudder also.
- Paddle weight 95
- Servo throws and mid pos at rudder very unsymetrical. Try to improve.
- Trim out the heli at classic mode.
- use ccpm trim at the servo end pos. to get really good climbing up / down behaviour
- be sure that the direction of the static torque compensation is set right

[th3tick]

I thought I'd trimmed things pretty well, but clearly, I got a lot of improvement. After re-centering the servo horns mechanically, the trims on the three cyclic servos went:

-40 -> -26
11 -> 2
-51 -> -23

I was also able to improve the tail to a -20 trim, and 54/62 for the travel limits. Those were copied to all banks.

I followed the rest of your settings, and stored them in bank 2, leaving my originals in 0, and another set from RJohn in bank 3.

I'm not quite sure what you mean by these last two, however:

- use ccpm trim at the servo end pos. to get really good climbing up / down behaviour
- be sure that the direction of the static torque compensation is set right

For the first, do you mean to just ensure the swash is level at both ends of the collective using CCPM trim?

Can you elaborate on how to get the static torque compensation direction correct?

Again, thank you for your time and attention. Sorry to be so much trouble.

John

[th3tick]

OK, I think I get the torque compensation. When I move the collective up quickly, the rudder gives a little thrust left, which I think is indeed backwards.

I see how to adjust it, but where does one reverse it?

John

[Flybar-less]

You can just make the value negative.

The CCMP trim under the Expert menu, I have never had to use if everthing is mechaically set right.

[th3tick]

OK, much improved. I feel like I'm on the verge of getting this right now.

Only one thing I noticed on the first flight: it seems to have a slow pitch nose-up roll to it, no matter the input. As soon as I stop, it starts pitching nose-up. Is this something to just use trim on the Tx to resolve?

I'd also be interested to know where you came up with the numbers you suggested. I wouldn't normally expect to have to go tweak the expert mode stuff initially, would I?

Now I'm excited to get out there once the weather improves a bit!

Thanks!
John

[th3tick]

You can just make the value negative.

The CCMP trim under the Expert menu, I have never had to use if everthing is mechaically set right.

I must be being dense. On the CCPM expert menu, what item do I adjust?

On further review, it actually is pushing right. I was noticing a little bump left going from full negative to full positive, but from mid-stick in either direction it adds a little right. It seemed to be behaving correctly today, as well, barring the pitch issue.

John

[Flybar-less]

Which setup do you like?

Don't use TX trim.

The cyclic comps can be adjusted independantly under Ex Rudder. My Ail and Elv usually are 5 points different. get the collective comp working right fist, the Elv, then Ail. Aileron seems to be the hardest and is if off can produce different results at different speeds. Check you CG too.

RV suggests setting the Deaband for cyclics to 5, I believe your tail setting is already at 5.

There's more versatility in the Expert menu.

[Flybar-less]

I think RV is taliking about finetrim under CCPM, which I have never used.

[th3tick]

Which setup do you like?

I'm going to have to defer that answer until I get some space to play in later today. So far, both are such an improvement, I haven't quite sorted it out yet.

My slow pitch up seems to have disappeared now. I hope it was a mistake I'd made all over the place that I just cleaned up caused by hitting "tab" instead of return after changing numbers directly. Ugh, that one hurt!

The biggest difference I saw between the two setups was that the proportional on both elevator and aileron was different - 35 vs. 95. Do you have a description of what that setting does?

I'm attaching my latest two, in case it helps anyone.

Thanks again, all :clappp
John

[Flybar-less]

My simple understanding of Proportional is that it is the amount of direct input from the stick that overides bell or any other stabilizing/counteracting settings. This is cool because you don't have to wait on the flybar, and this is what gives instant response, yet the Vstabi system retains stability and precision.

[th3tick]

There's more versatility in the Expert menu.

That's what I expected. I'm just surprised that you don't/can't get a well-behaved setup without the expert menu. I probably just started with crap, and didn't know how to tweak it.

Ah well, better flying ahead!

Thanks for all your efforts, RJohn! :thumbup:

You should write a tutorial for the settings you understand the meaning of ;)

John

[Flybar-less]

John,
Your bank 2 file has cyclic gain of 156%, this ought to be around 100%-110%.

[th3tick]

That was a leftover from my original setup. Not sure where it came from.

Is the cyclic gain like the normal gyro gain?

John

[Flybar-less]

No, but there has been some discussion on what exactly it does. If you changed the cyclic gain back to 100 you should be able to increase the cyclic ring to about 90.

[th3tick]

Well, I can't quite characterize why, but the one you sent me, tweaked for my setup changes, seems to fly a bit more connected. I clearly need to spend more time flying, but today was a bit cold to put in the kind of time I wanted to.

I'd say I did my first shiver maneuvers today. Just like crack, but far less control!

Oh, and I now know how to break up a V of geese faster than anything!

It flew great, and I'm much happier with it in general. Again, thanks.

John

[th3tick]

Next weirdness...

While poking at it on the bench, I noticed that the tail gradually creeps so that the slider gets all the way to the right. If I re-center it, it starts the creep again. The little graph on the expert shows it as the green line progressing down.

Just weird, and even though my servo doesn't bind, this makes the servo sing when it gets there. weird -> annoying.

John

[Flybar-less]

Drives me crazy too!