no bug Settings Without springs and ffb

[petsild]

Hi,

I use the cyclic setting No springs and ffb and for the pedals the central trimmer position mode.

Now when I use the trim button intended for the pedals it also activates the cyclic.

This causes me a double deflection, the other trim choices in the special behave the same way.

I haven't flown the Apache for a long time, I don't know when it has been malfunctioning.

[Lord Vader]

Hi, @petsild

Can you please show us or explain your assignments for the trimmer switch? 

[petsild]

I am using a springless joystick with a friction brake, I need the trim to be active only for the pedals.

So the settings Without springs and ffb, the trim should not interfere with the cyclic.

I am adding a picture of the Huey where the trim works correctly when set to No springs and ffb.

Thank you very much for the support.

[Raptor9]

@petsild, the red X symbols that you are seeing in the cyclic and pedal axes on the Controls Indicator overlay is the "force trim reference positions", which is what the Flight Management Computer (FMC) uses as a reference for SCAS and Hold mode logic. This is always present regardless of the trim settings you have selected in the Special tab of the Options.

The cyclic and pedal trim settings in the Special tab only affects how the game measures the axis of your hardware inputs when pressing/releasing the force trim button in the game, to account for mechanical differences between your physical hardware and the real AH-64D cyclic/pedals, but the force trim reference position is part of the AH-64D simulation itself.

There is only one force trim button in the AH-64D, which interrupts the force trim on both the cyclic and the pedals simultaneously. When the button is released, the force trim reference positions update to those positions in cyclic and pedals. But these reference positions are part of the FMC simulation, not the DCS input logic. You can read more about it in the DCS AH-64D Early Access Guide, in the AH-64D chapter, FMC section.

[petsild]

This is ideal for a spring joystick, but without springs it will increase the axis deflection for me and that is wrong.

[petsild]

I don't need trim on the X/Y axis if the lever stays in the position where I need it.
It works fine for Huey.

[Floyd1212]

Take a screenshot of your trim options in the Special Settings tab.

[firefox121]

En 2/6/2024 a las 12:52, petsild dijo:

Hi,

I use the cyclic setting No springs and ffb and for the pedals the central trimmer position mode.

Now when I use the trim button intended for the pedals it also activates the cyclic.

This causes me a double deflection, the other trim choices in the special behave the same way.

I haven't flown the Apache for a long time, I don't know when it has been malfunctioning.

Two questions, Are you using a FFB or non FFB joystick, if the answer is yes, go to axis tab and at the joy column set the ffb forces to minimun, this will prevent your you to deflect.

I uses to happen with my sidewinder ffb, other opftion is try to enable/disable ffb efects on main options screen and see the behaviour

Aso I your joy is a sidewinder ffb you must check the invert axis oprions at ffb setting axis

[Raptor9]

51 minutes ago, petsild said:

This is ideal for a spring joystick, but without springs it will increase the axis deflection for me and that is wrong.

I just tried it without any springs installed on my joystick and it worked as intended. When I moved my joystick to a position forward and left, then pressed the force trim switch, the stick position within the game remained in the exact same position. When I released the force trim switch, the stick position in the game still remained the same. I am not seeing any additional axis deflection simply from pressing the force trim switch as you are stating. The logic is working identically in the AH-64D and the UH-1H.

[petsild]

I've tried all trimmer settings.

Central Position trimmer mode for spring joystick the best choice, it is unusable for me.

Joystick Without Springs and FFB I have to confirm every deflection with a trim.

So far the best choice for me, but it requires updating deviations.

In theory, I should choose the INSTANT Trimmer FFB Friendly : but if I activate the trim, the deviation increases.
It is possible on a device with FFB that the trim behaves correctly and there is no doubling of deviations.

[Raptor9]

Instant Trim can be used with a spring-centered stick or with a FFB stick. I use a spring-centered stick and use Instant Trim myself (this is the same logic as the Default trim setting that has been around since DCS Black Shark first came out in 2009).

I believe the confusion lies with the role that the force trim reference position plays in DCS AH-64D. To reiterate, it has nothing to do with the trim settings from the Special options. It is a function of the real AH-64D's FMC logic, and is updated every time the pilot stops pressing the force trim, regardless of the trim emulation settings in the game.

[petsild]

I have to describe the problem more and add the behavior of the trimmer in the track file or video.

[petsild]

After some testing, I found a larger range of problems.

Just look at the very short track, I will leave out the foot pedals, they are not the topic of discussion.

In stable flight, I activate force trim and everything behaves correctly so far.

The helicopter maintains altitude and speed, but if I perform a trim reset, the cyclic deflections suddenly change and the Apache flies straight into the ground.

At the same time, she is physically still in the same position, so the center of gravity has probably changed?

When repeating with AL/Right on, the height stabilization does not respond.

 

The same simulation this time with the Huey, where the activation of the trim and reset does not interfere with the cyclic only for the foot pedals and so it is completely correct when the joystick is without springs with a friction brake.

Htrim.trk Atrim.trk

[Lord Vader]

@petsild

The Trim Reset button serves the purpose of removing all added trim positions to 0 (zero) deflection. If you keep the stick in the same position after pressing it, it will read that current position of the stick and add that input. If you return the stick to the pure center when you press it, does the behaviour still occur?

Also, the AH-64D is very peculiar. In activate the AL mode on the Hold mode (trimmer Right), the aircraft needs to be in stable flight or a stable hover, if not it will never engage if you are beyond the limitations.

[petsild]

 

We still don't understand, I don't need a trim for cyclic, the Specials Joystick Without Springs and ffb option should work correctly for that!
With this setting, it has to ignore the cyclic trim, and unfortunately that doesn't happen.

[Floyd1212]

I also watched the track, and see you using the Trim Reset function, which causes the nose to dive.  (This is odd to me, as I am used to the nose pitching up dramatically when the Trim Reset is used.)

You probably don't ever want to use the Trim Reset with a springless joystick with friction brake anyway.  That function is designed for people with sprung joysticks to immediately return the trimmed state of the aircraft back to zero to match the neutral state of their centered joystick; mostly to get them out of trouble if their currently trimmed state is unmanageable.

You should be holding Force Trim Release (FTR) while moving your cyclic, then release FTR when you have your desired attitude.  Your stick should stay in place because of the friction brake, and the red cross in the controls indicator should be centered over the white diamond.

[Raptor9]

6 hours ago, petsild said:

We still don't understand, I don't need a trim for cyclic, the Specials Joystick Without Springs and ffb option should work correctly for that!
With this setting, it has to ignore the cyclic trim, and unfortunately that doesn't happen.

Petsild, pressing the Force Trim/Hold Mode switch on the AH-64D's cyclic to the Force Trim Release (FTR) position does more than just interrupt the force trim that holds the cyclic and pedals in place. In the UH-1H, pressing the force trim button releases the force trim brakes on the cyclic and only this. But as I stated in the previous comments, the FTR (ie, "force trim" button) in the AH-64D does that and more. It interacts with the AH-64D's Flight Management Computer, which is what the red X symbol represents as the FMC's force trim reference position. As I said above, I highly recommend you review the FMC section in the Early Access Guide. The AH-64D is not a UH-1H; it is much more advanced with a complex flight control system.

The Trim Reset command is intended to return the offset positions of the simulated controls in the game cockpit to center, to re-sync their positions to a spring-centered joystick that a player is using. The command is not intended to be used with a spring-less joystick. What is happening is you have your stick in a position that is offset from center, with the FMC's force trim reference at the same position. When you press the Trim Reset command, the game is interpreting this as rapidly returning the cyclic's force trim reference to center and then instantly applying a forward cyclic deflection forward away from it, which is why the SCAS is commanding an additional motion to the swashplate position (green cross).

Floyd1212 brings up this point and other valuable points above. If you do not wish to read the FMC section in the Early Access Guide, then what it comes down to is that you should be pressing the force trim any time you move the cyclic and/or pedals, and then stop pressing it when you achieve your desired attitude or flight state.

A thread that you may find useful is linked below. The OP uses a similar setup with a physical stick that holds its position when he lets go, and he too was getting confused as to why he should still trim when he thought it was unnecessary. Please pay attention to my responses in that thread.

 

[petsild]

So I read it and I try to absorb why such a simple thing is made so complicated.

Mainly the condition to constantly confirm every deviation.

I turned on the custom trimmer from VKB again and the result of the behavior is the same as the Huey helicopter.

I performed a few basic maneuvers and did not notice any negative effects at all.

What am I missing if I fly cyclic without trim?

Edited June 5, 2024 by petsild

[Floyd1212]

1 hour ago, petsild said:

What am I missing if I fly cyclic without trim?

For one thing, when you want to engage the Altitude and Attitude Hold modes, you need to trim out the aircraft before enabling them.

[petsild]

I tried that first thing, both functions work without trim.