Vortex setup question

[mark_w]

Evening,

I have been running through the setup of my vortex on my 700LE with a dfc head and all is going well.

When I get the 8 degrees menu I have 2 questions

1. Mine goes to -8 not 8, but all the swash movements are ok, is this ok?
2. The percentage that I need to set to get 8 degrees is 79% is this too low or ok?

Thanks in advance.

Mark

[Flat Eric]

+/- is fine, it's 8 degrees you are looking for either way I believe. 79% will be fine, I am setting one up on the same heli and got 80%

[Andy from Sandy]

79% will be fine, I am setting one up on the same heli and got 80%

I am not going to disagree but how do you know it is going to be fine or optimal?

My setup also has low numbers and I know it works but it may not be optimal.

[mark_w]

Vortex setup question

My setup also has low numbers and I know it works but it may not be optimal.

Ok, so hopefully it will fly, even if not optimal.

Do you know what the value represents? Is it todo with the amount of servo travel needed to gain 8degrees? Thus being different on different helis based on the linkage setup and location of the ball on servo horn?

[Flat Eric]

I am not going to disagree but how do you know it is going to be fine or optimal?

My setup also has low numbers and I know it works but it may not be optimal.

I am no expert but Angelos says to keep it below 120 and if I remember correctly the starting value is 80

[Andy from Sandy]

Do you know what the value represents?

No. At present there is probably not alot of data but you know with those other guy's unit they show you where you need to be and what represents the best place to aim for.

I just like to ask when people say something will be fine, how they know that is all.

[mark_w]

Vortex setup question

I just like to ask when people say something will be fine, how they know that is all.

Sounds sensible to me.


I might have a play around with link locations tomorrow and try to get the value closer to 100% or at least try and understand how it changes.

[Flat Eric]

No. At present there is probably not alot of data but you know with those other guy's unit they show you where you need to be and what represents the best place to aim for.

I just like to ask when people say something will be fine, how they know that is all.

If the instructions say to keep it below 120 why would 79 not be ok?

[Andy from Sandy]

Dont know where you are trying to go with this

Absolutely no-where. I read that the value wants to be below the 120 but just wondered if there was an optimal value that would work better than anything else.
Honestly, nothing more sinister than that.

[mark_w]

Vortex setup question

I think this thread has gone in a slightly different direction.

Started out as is 79 ok, which I am happy to accept your answer that it is.

Now the question is, is it optimal and what does the value actually mean?

[Andy from Sandy]

Sorry if you think I am saying you have something wrong. I am not doing that. The numbers I have are also low and the model is flying fine. It is more about information gathering to see if a particular value would be even better somehow.

[raptorheli2]

Evening,

I have been running through the setup of my vortex on my 700LE with a dfc head and all is going well.

When I get the 8 degrees menu I have 2 questions

1. Mine goes to -8 not 8, but all the swash movements are ok, is this ok?
2. The percentage that I need to set to get 8 degrees is 79% is this too low or ok?

Thanks in advance.

Mark

1. +/- doesn't matter, if you flip your gauge it will read the opposite. the important thing is the 8 deg to start with and the servos/corrections go the correct way.

2. the reason 120 was mentioned was like everything there is a sweet spot. it is exactly the same as the tail except your now on the swash. if you are between 80-120% i personally would leave it there. e.g 120 on the pod to get 8 deg means your mechanical gain is perhaps too low (depending on heli design). in other words you could maybe go out a hole on the servos and get this down. there is a lot to this from swash size, ball length from swash to the head, servos used (yes they do travel diff amounts) etc.

hope that helps.

cheers

[Angelos]

One thing to consider... different servos will travel difference distance for a given signal. I have observed as much as 50% more travel. So if one servo was at it's ideal travel at 80% the other would be at 120%. Because of this difference I have allowed the 8deg adjustment to go past 120% but I don't think this is really necessary and for the majority of cases it means that if you have gone that far you probably need to move your ball links one hole out.

Given the differences between servos it is absolutely not possible to say between x% and y% on a parameter is good and if you are above of below that is not optimal. That applies for the Vortex and every other flybarless system. So how do I set mine? A bit of experience and roughly by eye though you can use a protractor of you wish (plenty to download and print on the web). So here is what we aim for...

The servo ball link moves on a arch. The push-rod tracks the ball link but because of their mechanical arrangement their relationship is a sinusoidal. As the attached plot shows the first 35 degrees (left or right from the servo center) are practically linear. Thus the push-rod travel is proportional to servo rotation. However as we go past 35 degrees the push-rod starts to move less and less. Past 60 degrees the non linearity get very exaggerated.



Conclusion:

If you can make the maximum servo travel fall between 50 and 60 degrees (full collective and full cyclic combined) I'd say it is very good.

If you are much below 50 degrees then you are not fully utilising the servo travel and thus you are losing some of the servo resolution. Move the ball links one hole in which increase the servo travel.

If you are above 60 degrees then you start to introduce a lot on non-linearity in your swashplate geometry. Move the ball links one hole out which will reduce the overall servo travel.

Cheers,
Angelos

[mark_w]

Vortex setup question

Angelos - thanks for taking the time to explain, I am going to have a look at see what is happening on my heli just out of interest.



I don't think I will be able to get above the 79% as from what I am reading above I would need to move the balls in further which I cannot do. But I am now happy that this value is ok to use.

Tail setup next and I have just seen the tail vid is up, perfect timing