RunRyder - 500 VBar issue

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e-Mikado Logo 400 500 600 > 500 VBar issue

GScott
Key Veteran
Location: Lewis Center, OH

I'm still a VBar newbie but I'm having an issue with my Logo 500 and I'm not sure which setting to change. When I come out of big loops the tail shakes very bad. Sometimes it seems the entire heli is oscilating. I'm running a Hacker 10L with a 9254 on the tail and using Extended mode. I believe my tail limits are 47 and 52 and the gain is 50. Is this just a gyro gain issue or something else?

10-19-2008 04:42 PM

firechicken
Heliman
Location: ma

is it just a tail wag?... could be that your normal gain (p) is too high.

try dropping it by 5 points at a time

10-19-2008 06:13 PM

dahld
Senior Heliman
Location: Bakersfield, CA, USA

A few questions

Is the shake only in the tail, or can it possibly be the whole heli? And, does your head speed go way up as a result of coming out of the bottom of a loop?

The reason I'm asking is, I'm trying to see if the shake is head speed dependent. If you're not sure, then run the head speed up in a hover, and see if the heli shows any signs of shaking like you see at the bottom of a loop. This info might make figuring out what's happening easier.

Dave Dahl

Kyle Dahl (age 15) - Team Mikado
Team FlightPower USA
Team A Main Hobbies (amainhobbies.com)

10-20-2008 04:26 AM

Jafa
Elite Veteran
Location: Sydney, Australia

10-20-2008 09:33 AM

GScott
Key Veteran
Location: Lewis Center, OH

After flying yesterday I think it is just the tail. I reduced the gain to 46 and it helped but it still occassionally shakes. I also noticed that it doesn't roll quite right. I can only manage 1 roll in FFF before I lose all momentum. I've uploaded my current config to my gallery. It's in a zip file named Logo500Vbar.

10-20-2008 02:53 PM

GScott
Key Veteran
Location: Lewis Center, OH

Just realized the config file is not the latest one. I'll post the correct one this evening.

10-20-2008 03:17 PM

Jag72
Elite Veteran
Location: 20 minutes south of Boston Mass...

couple of things to look at...

you can either focus on the gain for the tail AND/OR

you need to look at the Torque compensation values for the Ail/ELEV/Collective...

if these aren't set right the tail can have issues...

10-20-2008 05:05 PM

LJS
Veteran
Location: Minnesota, USA

Hi GS,

My flybarred Logo 500 also lost momentum in right rolls during forward flight because the tail would drop. I've been told that it's a phasing issue. I corrected it with a 7% up elevator mix with right aileron.

Something for you to check is to see if it does the same thing when you roll to the left. If it's a phasing issue, the nose should stay level or actually drop when you roll to the left. I didn't add any down elevator mix to the left aileron, but I've been told that that is common too.

Hope that helps.

Keep 'em flying.

LJS

600E, 1910 1Y, 8S FP4270, GY611
600N, OS50 Hyper, GY611
Logo 5003D, 600+, 6S TP 5000, DS760

10-20-2008 06:17 PM

OICU812
rrProfessor
Location: Grande Prairie, Alberta, Canada

LJS this is Vstabi, if you are getting phasing in Vstabi, you need to correct it mechanically by the swash driver, or simply add right or left clicks into the swash menu. The vstabit takes out interactions that a flybar would not.

...Once upon a time there were Nitros, flybars and frequency pins...

10-20-2008 07:03 PM

GScott
Key Veteran
Location: Lewis Center, OH

My current config has been uploaded to my gallery.

10-21-2008 01:41 AM

Jafa
Elite Veteran
Location: Sydney, Australia

I will upload my setup on Monday for you to look at

You tail setup is a little unusual and the gain is way too low
(so I assume your tail mechanical gain is way too high)

Did you use the live menu and then set the sub trims of the TX
to get zero input on the collective, aileron, elevator and tail channels?

Have you also increased the ATV end points on those channels
to get the live menu throw values closer to 2000?
I think not (it's not documented I think)
as you have a very high collective rate
and an extremely high tail rate

Increasing the TX end points to get live values closer to 2000
gives you more granuality of control
and gives you greater throws within VStabi

It would be really good if you could find a better horn for the tail
(or drill a hole in the round disc at the exact correct possition) to avoid using trim on the tail

Then use adjustment mode to play with the rudder
(don't use the TX stick - use the rudder slider in adjustment mode)
You want to get the travel limits the same on both sides
and you want to use a reasonable servo throw value
Your throws are a little small, mine are 60
so you need to move the ball on the tail servo
closer to the center (mine is about 14mm)
Once your throws are the same you can set the center position to 0

You should be able to reduce your tail rate from 150 to 100
(mine is crazy fast at 100 but I know very advanced pilots
do run very high values like 150)

At this point you will be able to lift the tail gain to ~75

You will probably also be able to reduce your
collective to tail mixing from 30 to 25
Is suspect you had to increase this to mask the tail setup issues

Your -44 setting for the piruette optimization
does not look right at all, mine is -18
(This will just change the feel
it wont cause the problem you have encountered)

After you have increased your TX collective ATV end points
you will be able to reduce your collective common on the swash page
(mine is 85)

You've got a bit of trim on the cyclic channels
This has forced you to to mess with the high/low trims
(because the trim results in unequal travels)
This will work - but you need to make one change
I assume your trim settings are to level the swash -this wont fly correctly
I also assume you did the trims in classic mode?
VStabi needs +8 added to the elevator at max collective
and -8 added to the elevator at min collective
So your max collective elevator value sould be +4
and your min collective elevator value should be -7

Well, that's what I would do,
give it a go and see what you think

Lepton | TRex600Nitro | Sceadu | Freya | Avant | Predator Carbon Max

10-21-2008 10:24 AM

GScott
Key Veteran
Location: Lewis Center, OH

Thanks Jafa.

The heli was purchased used and I have just been tweaking the setup it came with. Looks like I just need to start from scratch. Is there a good start to finish tutorial anywhere? I read the VBar Wiki but there are apparently some gaps. I don't remember anything about the Live menu setup you described. I do have a few questions.

1.) What settings do I use to level the swash? If all the servo arms are 90 degrees and the rods are equal length and it is still off.

2.) CCPM interaction. How is this corrected? In my non-Vbar setups I would use travel adjust at high and low stick but on the VBar I used the Fine Adjust.

3.) Is the Live mode adjustment documented on the Wiki or anywhere?

Is the Logo 500 template a good starting point for a new setup? Thanks.

Gary

10-21-2008 02:31 PM

Jafa
Elite Veteran
Location: Sydney, Australia

No problem Gary - happy to help
Takes a while to get up to speed on VStabi

1) Something is wrong with your mechanical setup
Either the servo arms are not ar 90 degrees
or the rods are not equal
If both were perfect the swash would be level

If you don't fix it mechancially,
You have to be in classic mode and use the software trim
The latest software has a setup sequence to follow
It's pretty easy and gets you into the zone nicely

2) Fine trim is correct (in classic mode)
But if you can get your horns setup at 90 deg
you will find you don't need any fine trim

But note that you need the +8 & - 8 added to the elevator trim
This is why you are loosing forward speed
the nose is slowly going upwards
If you do pitch pumping you will find that the tail does down also
Once you add +/- 8 to the elevator this is all fixed

So get the swash level and then add these values to the elevator

3) Somewhere I saw a brief mention about setting up the tx by watching live mode
but it's really something that people in the field have come up with

4) The Logo 500 preset is very safe and flys well
It's just not a hot setup
Great starting point and easy to improve cyclics from there

Lepton | TRex600Nitro | Sceadu | Freya | Avant | Predator Carbon Max

10-21-2008 10:18 PM

ivor-bigen
Senior Heliman
Location: Harlow. UK

nice post jafa.
does this "But note that you need the +8 & - 8 added to the elevator trim"
aply to the other mikados eg a 400. i am tweeking a 400vbar (my first ever vbar)

logo 10, 500 3d, 14 carbon, 400vbar , zoom 450, raptor 90, xcell fury

10-21-2008 10:42 PM

HOMEPAGE

Jafa
Elite Veteran
Location: Sydney, Australia

It applies to all VStabi installations as far as I know

1) If you try to do say 5 consecutive rolls
and find you loose forward speed
or in a bad case the heli wants to enter a loop
2) Stationary aileron flips/rolls result in nose up / tail down
2) Climb 30 feet and then come down hard - repeat a few times
You may find the nose goes up and the tail does down

These in flight behaviors all show
that you need these elevator correction values

But the values to use do differ from model to model!
You can run the software (not plugged into your model)
and get the preset for your model
You can then see the default setting appropriate for your model
This is an excellent place to start

Make sure you exit the software
I once messed around with the settings
and then plugged my model into the computer
I expected the software to obtain my model settings
Instead it down loaded the on screen settings into the model
Lucky I had a backup of my model settings on disk

Cheers...

Lepton | TRex600Nitro | Sceadu | Freya | Avant | Predator Carbon Max

10-22-2008 01:46 AM

GScott
Key Veteran
Location: Lewis Center, OH

I did a factory reset and loaded the Logo 500 template. I was able to get the servo mid's much better this time. I also changed the travel adjustment on all the necessary channels to get 2000 in the Live menu. Most ended up around 125%.

10-22-2008 02:08 AM

Jafa
Elite Veteran
Location: Sydney, Australia

10-22-2008 10:04 AM

OICU812
rrProfessor
Location: Grande Prairie, Alberta, Canada

I run +14/-14 on elevator values on my 500 to avoid the dolphin effect, on my 600s I think around same as well. Also you should do climbouts with no wind and see if it pulls either way, then if needed you can adjust your aileron values in that same menu, then go inverted no wind again and do negative climbout and observe if it leads a certain path, then of course you can correct this by changing the bottom aileron value. This if not adjusted can offer some weird elevator tic tocs and also throw off your aileron tic tocs and four point tic tocs and big bens n stuff. BTW all my tx values are 100%, I use the cyclic gain in the ccpm menu I think to get my % of throw over 8%. 103% on logo 400, 109% on Logo 600 and 700 gets you this throw with tx values of 100%. Just another way, you can do the endpoints as well as mentioned, preference is all I like to keep it in the software.

...Once upon a time there were Nitros, flybars and frequency pins...

10-22-2008 10:38 AM

Jafa
Elite Veteran
Location: Sydney, Australia

Yup - that's one thing that can confuse people
Different techniques to achieve the same thing
It's important to understand how/why they work

My Logo500 is flying pretty darn well
The climbs are true (but have not had a really calm day)
The tail down tic tocs are fine

The aileron tic tocs have a bit of an elevator pull
so yeah, maybe I need to use more than 8 points

The aileron tic toc action has a slight diagonal effect
(rather than rotation on true 90 degree vertical it may be 95 degrees)
I was wondering if that would be my phasing?

Lepton | TRex600Nitro | Sceadu | Freya | Avant | Predator Carbon Max

10-22-2008 12:25 PM

GScott
Key Veteran
Location: Lewis Center, OH

What is the best way to increase the cyclic response? I do like fast snappy rolls and flips.

10-22-2008 02:01 PM

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e-Mikado Logo 400 500 600 > 500 VBar issue

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