KA50 Target Designator "a bad JOKE"

[RagnarDa]

The issue is that some of the people here claim that this nose-dive is a bug. I've said it's not (because of the explanation I gave in my post and yours here (they are the same).

 

But some people claim it's still a bug because with FFB there is no dive. And indeed if that is the case that would be suspicious (I'd expect the dive to be there always). I'm just trying to understand. I know I had my own share of AP doubts back in the day.

Ah, ok. But I do think the game treats FFB and non-FFB sticks entirely differently. The nose-dive happens because the player doesn't center his stick fast enough, but this shouldn't happen with a FFB because it doesn't need to be centered. Its real center position is irrelevant, the center-position of the FFB is where it has the least count-force which corresponds to the actual center position of the non-FFB.

[Havner]

The nose-dive happens because the player doesn't center his stick fast enough

 

In the previous post you said yourself that this is not possible because of the central position trimmer mode and that the nose dive is caused by the release of 20% AP authority (and I agree with those). But now you contradict yourself :smilewink:

[sorcer3r]

The nose-dive happens because the player doesn't center his stick fast enough,...

 

No, that is not what I wrote:

Virtual stick will also move without input = non-ffb stick is already in its central position.

[RagnarDa]

In the previous post you said yourself that this is not possible because of the central position trimmer mode and that the nose dive is caused by the release of 20% AP authority (and I agree with those). But now you contradict yourself :smilewink:

Huh? My comment was with the assumption that the Central Position Trimmer mode is off. When you click the trimmer button with stick deflected on a non-ffb stick this deflection gets added to your virtual stick deflection so if you deflect your real-life stick say 5 degrees, the virtual stick will be 5 degrees. If you press and release the trimmer without moving the real-life stick the virtual stick will be 10 degrees deflected. If you do the same again it will be 15 degrees deflected and so on. Hence you need to quickly move your stick to the center after you have trimmed else you will make a hard manouver. This is the original behavior as I have always understood it.

[Havner]

Hence you need to quickly move your stick to the center after you have trimmed else you will make a hard manouver. This is the original behavior as I have always understood it.

 

 

I assumed in discussion that we know how to trimm properly so either we use central position trimmer mode or move the stick to the center within 0.5s :-)

 

I'm trying to figure out how the AP behaves excluding person's mistakes in handling the stick.

 

So the only explanation I got for non-FFB is 20% AP authority release on click trimm. I'd like to see a track with FFB stick.

[sorcer3r]

Huh? My comment was with the assumption that the Central Position Trimmer mode is off. When you click the trimmer button with stick deflected on a non-ffb stick this deflection gets added to your virtual stick deflection so if you deflect your real-life stick say 5 degrees, the virtual stick will be 5 degrees. If you press and release the trimmer without moving the real-life stick the virtual stick will be 10 degrees deflected. If you do the same again it will be 15 degrees deflected and so on. Hence you need to quickly move your stick to the center after you have trimmed else you will make a hard manouver. This is the original behavior as I have always understood it.

 

But the question is how should the virtual stick behave when your non-ffb stick is in central position before trimming.

[RagnarDa]

But the question is how should the virtual stick behave when your non-ffb stick is in central position before trimming.

Do you mean that if you keep your real-life stick centered and click the trim, the virtual stick moves (in the cockpit)?

[sorcer3r]

Do you mean that if you keep your real-life stick centered and click the trim, the virtual stick moves (in the cockpit)?

 

yes.

[Flagrum]

Given the situation that the stick is in the neutral position ("centered" wether it is the physical center in case of a non-FFB stick or the current, trimmed center of a FFB stick) AND the helo is in a stable attitude, the AP does not generate any input - as it is not necessary.

 

If the pilot now applies a force to the stick and causes the helo to change its attitude, the AP tries to counter that (within it's authority). If the pilot now depresses the trimmer button, the AP disengages and the input of the AP vanishes.

 

Example:

 

1. Stable attitude with pitch 30%, stick is centered, AP applies +-0%
   
2. Pilot increases pitch to 40% (nose goes down), AP applies -10% (nose comes up slowly again), helo is (physically) again at pitch 30%
   
3. Pilot depresses trimmer button, AP disengages and applies +-0%, stick is still at 40%, helo is at 30% -> nose goes down to 40%
   
4. Pilot releases trimmer (and in case of non-FFB re-centers stick), helo is at 40%, stick is centered, AP applies +-0%
   

So far, this behaviour is the same, no matter if FFB or non-FFB.

 

Now Click-Trim:

The difference to the example above is: in case of FFB, the helo has no time to really react to the difference in pitch of stick=40%, helo=30%, AP=-10% (see point 3). The re-centering of the FFB stick is instanteous and immediately the situation of point 4 is archieved. --> no/very tiny nose down effect

 

For a non-FFB, central trimmer stick, there IS quite a delay until the stick is centered -> nose drops. Basically, for a non-FFB, central trimmer stick, the "release trimmer to set the current attitude as new trimmed attitude" is not complete until the stick is physically re-centered.

[Havner]

But the question is how should the virtual stick behave when your non-ffb stick is in central position before trimming.

 

Not exactly, the original issue was about nose dive, so the stick is not in the central position (but deflected forward without the trimm).

But with the central position trimmer mode it shouldn't move anyway when you click trimm.

[RagnarDa]

I assumed in discussion that we know how to trimm properly so either we use central position trimmer mode or move the stick to the center within 0.5s :-)

 

I'm trying to figure out how the AP behaves excluding person's mistakes in handling the stick.

 

So the only explanation I got for non-FFB is 20% AP authority release on click trimm. I'd like to see a track with FFB stick.

I believe there are two separate things going on here. When you are flying fast forward and have stick trimmed hard forward - more forward (say 30 degrees nose-down) than is required to keep the attitude that has been last commanded to the AP (say 20 degrees nose-down) - the stick will be deflected a lot forward but the AP is trying its best to move the nose up to 20 degrees. You are also (probably unconciously) deflecting your real-life stick forward, which means the AP is fighting both your trimmer position and your real-life stick. Now if you move the stick forward even more (to increased the nose-down a bit more) and then press the trimmer two things will happen: first the AP will disengage and the swashplate will move 20% forward, then you new trimmer position will be added to your already large deflection which will give you a hard nose-down. Always remember that the trimmer-button both commands which attitude the AP-attitude hold will strive for and trimmer position addition to the previous trimmed position.

[karambiatos]

 

For a non-FFB, central trimmer stick, there IS quite a delay until the stick is centered -> nose drops. Basically, for a non-FFB, central trimmer stick, the "release trimmer to set the current attitude as new trimmed attitude" is not complete until the stick is physically re-centered.

 

even with centered stick options clicked on, the helicopter will still have a 10 degree nose drop when your release the trim.

[Havner]

For a non-FFB, central trimmer stick, there IS quite a delay until the stick is centered -> nose drops. Basically, for a non-FFB, central trimmer stick, the "release trimmer to set the current attitude as new trimmed attitude" is not complete until the stick is physically re-centered.

 

In Central Position Trimmer Mode this doesn't happen. The AP just assigns whatever it needs to assign, virtual controls get a new center and your physical are blocked until you recenter them. There is no delay in AP. The only delay is for you to regain control of the heli.

 

then you new trimmer position will be added to your already large deflection which will give you a hard nose-down.

 

How can those happen with Central Position Trimmer mode?

[karambiatos]

if someone wants to easily see how everthing works in relation to the AP and joysticks, go to D:\Program Files\Eagle Dynamics\DCS World\Mods\aircrafts\Ka-50\FM

and in the FMOptions.lua file, change

HelicopterTrimmerTauInverse = 7.0

to

HelicopterTrimmerTauInverse = 1.0

or

HelicopterTrimmerTauInverse = 0.1

 

thisll slow down the time the trimmer takes to kick in.

[RagnarDa]

even with centered stick options clicked on, the helicopter will still have a 10 degree nose drop when your release the trim.

 

How can those happen with Central Position Trimmer mode?

Actually my comment was under the assumption that the Central Position Trimmer Mode is off. First of all make sure there isn't any jitter in your controls that would prematurely recenter your stick. I just checked with the Central Position Trimmer Mode and trimming position that is stored is the deflection you had when you release the trimmer unlike the normal mode, so this mode is probably more useful if you are using the click-trim method and not the hold-release method.

[sorcer3r]

If you say "nose goes down" does it also mean the stick in your cockpit will move forward?

 

Pilot depresses trimmer button, AP disengages and applies +-0%, stick is still at 40%, helo is at 30% -> nose goes down to 40%

[Flagrum]

If you say "nose goes down" does it also mean the stick in your cockpit will move forward?

No. The stick in the cockpit only moves if the player deflects the joystick. The AP causes no movements of the controls.

 

Maybe you confuse this effect with the A-10C? There the stick in the cockpit and also a FFB joystick move if you use the trim hat.

[sorcer3r]

No. The stick in the cockpit only moves if the player deflects the joystick. The AP causes no movements of the controls.

 

If my stick is in central position (no ffb) and I press the trim button I see a small movment of the virtual stick. This could cause the dive issue on nose down trim I think.

I will upload a trackfile later

[Havner]

If my stick is in central position (no ffb) and I press the trim button I see a small movment of the virtual stick. This could cause the dive issue on nose down trim I think.

I will upload a trackfile later

 

The nose dive is when your stick is deflected significantly without the trimmer and then you press trimm.

[lxsapper]

The nose dive is cause like it was mentioned before by the fact that you are not returning the sick to center fast enough (0.5s), and it's very hard to do smothly and acuratly. Thre is no nose dive in central trimmer position if you are smoth with the controls. With a FFB joystick for the most part there is no nose dive but you run into other possible problems. With my MSFF2 I find that the possible positions the trimmer holds the stick in both the Y and X axis are actually very crude and spaced. I don't know if this is a hardware limitation or if the software not sending apropriate data to the joystick, but there's a good 3-4mm stick travel distance between the positions I can get my MSFF2 to hold. This causes bumping when trimming. Click-trimming seems to agravate the problem, and the best aproach apears to be using this aproach: 1- holding the trim button, 2 - Moving the Cyclic, 3 - Releasing the trim button. That way it's possible to be very precise with preaty much no bumping and no surprise nose dips whatsoever.

[karambiatos]

The nose dive is cause like it was mentioned before by the fact that you are not returning the sick to center fast enough (0.5s),

so when i make the trim kick in, after 2 seconds the dive still happens.

 

how do you explain that?

[Havner]

Thre is no nose dive in central trimmer position if you are smoth with the controls.

 

Not true.

 

See the attached track. This is made WITH Central Position Trimmer Mode. TM Warthog (non-FFB obviously).

 

1. I press and hold the trimmer before take off

2. With the trimmer pressed I stabilize the heli at 75-80 and release the trimmer

3. I let it stabilize (HUD zoom, 80 is visible).

4. Then without touching the trimmer I push the stick forward (it's clearly seen that I fight the AP)

5. I accelerate to around 230 and let is stabilize.

6. Then I hit the trimmer (press and release)

 

Nose dive clearly visible.

The virtual stick in the bottom left corner didn't move at all. If you move the camera down a little you'll see that the stick inside the cockpit didn't move as well.

 

And I have no problem with this dive (it's not a bug to me) as I explain it (the best I can) with AP immediately releasing its 20% authority when you "click" the trimmer. I've described this in the following post (with image):

http://forums.eagle.ru/showpost.php?p=2071011&postcount=52

 

Now, what I find strange is that people claim that this particular thing (like on the track) won't happen with FFB stick:

http://forums.eagle.ru/showpost.php?p=2071467&postcount=65

 

I find it hard to believe. But if that is really the case then my explanation must be wrong and there is some bug somewhere.

 

That's why I'd like to ask once again for someone with FFB stick to make exactly the same track I did and post it here please.

trimmer-nose-dive.trk

Edited May 21, 2014 by Havner

[BaD CrC]

I thought this topic was about how ED is dropping down support on BS, not on how to use trim....

[Flagrum]

I thought this topic was about how ED is dropping down support on BS, not on how to use trim....

This is about how ED is dropping support on BS and not fixing trim ... if it needs fixing ... or so. :o)

[Itkovian]

Thanks. I know it's incorrect thing to do. I just want some confirmation whether it behaves differently than it does on non-FFB.

 

I tested it, and I can confirm that there is no sudden dive. The only "jerky" movement is caused by your own hand jerking when the FFB suddenly cuts out and back in. If you have proper control, click trimming will not cause a nose dive or anything of the sort with FFB.