read more: FFB Tweaks

I've worked with x4fab to add a new feature to the Custom Shaders Patch (as of 0.1.51) and the description is fairly brief so I thought it's worth going into a bit more detail about what this does.

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Gyro Implementation

[ ] Active check to enable
Strength 25% adjust effect strength
AC has an "Experimental Gyro" FFB effect whose purpose was adding gyroscopic effects to the steering. It never lost the experimental tag and all it's generally recommended for is damping down oscillations on direct drive wheels.
This is that, developed slightly further based on my understanding of the nature of gyroscopic forces. I have a pretty solid case for making this change, and I believe this force exists in actual cars, and AC's original experimental gyro does not.

The developed version still suits the purpose of damping oscillations, but more importantly it decouples the body from the front wheels - so if the front wheels are pointing in a direction and the body moves around them, no gyroscopic precession happens, and no force is generated. Concretely, what we're talking about here is oversteer - on the original experimental gyro, the force acts counter to self-alignment during oversteer. With this new implementation, self-alignment is allowed to occur freely, or, if the oversteer is so quick that the wheels can't self-align, it'll actually push in the direction of alignment.

25% is simply equivalent to the original force multiplier used on experimental gyro when merging it with other FFB forces. Ultimately, the same as the other amplification ffb effects like road and slip effect, the slider is available to magnify it if your hardware's limitations are obscuring the effect.
As of CSP 0.1.53 the strength slider is outdated. A calculation using the suspension geometry now provides the right precession-based force for each car.
The description is a little bit misleading; this replaces "Experimental Gyro" so disabling it is superfluous, if this is Active, experimental gyro is not. Still, it won't hurt to disable experimental gyro and be certain it's off.

Now that I've said what the intent is, I will also note the following: this changes FFB in pretty much every dynamic situation. It's not just an improvement for drift cars or for vintage cars that oversteer constantly; any time the car moves around on the tires it feels slightly different from before. To me, it's a positive change, it's clearer what the car is doing, and I have heard similarly positive comments from testers. Nonetheless, I am not omniscient, I have not driven all these cars in real life, it's up to you to decide whether it improves your game or gives you better sim feeling the rubber or what. Modifying games to improve the FFB is a fine tradition starting with some extremely thorough efforts in rfactor1, and this is no different (maybe a bit easier to install).

I will note that it slightly increases max forces when cornering so if you have stuff set up to barely clip, you'll need an adjustment downward in global ffb mult.

Range Compression

Range compression 100% - 100% is the "default off" of this effect
[ ] Range compression assist - check to convert cars' "steer assist" into range compression.

New FFB Tweak available as of 0.1.53. The name comes from the audio world, where dynamic range compression means bringing up the quiet sounds while leaving loud sounds at their original volume. This is a much more second derivative friendly version of the Gamma effect.

The percentage is straightforward: Set it to how much you want to multiply small forces. Or adjust it in sync with your overall gain if you want to maintain the level of small forces and change large forces. For example, 200% compression + 50% gain = original 100% on small forces, larger forces decrease. If you're curious, the curve at the point of maximum force is simply the inverse, 200% compression will cause large forces 50% of the original delta in force. But in combination with 50% gain, you're moving the original maximum force downward and the ceiling before the game clips is much higher.

Think of this like power steering: you only want it to assist the heavy forces and give you maximum feel of the light forces.

This is very much an "adjust to taste" thing, it operates smoothly enough that you're safe running it upward of 300%, and I have seen IRL data indicating that manufacturers effectively go as high as 600% in power steering systems, when they want to bring 20+N forces down to a comfortable 2-3N.

Steer assist is a built in per-car feature of AC that applies a gamma function to that car's FFB. If you check Range compression assist, then FFB Tweaks will calculate an appropriate range compression adjustment, and disable steer assist. This should give you a far more normal FFB feeling (no weird bumps around center) while retaining the original goal of giving high downforce cars enough low-speed FFB to be drivable.
 
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Guess it all depends on the wheel, car and what exactly is meant by oscillation here.
On Simucube2 I did not notice significant change with oscillation on straightaways, Stereo also posted on discord new beta version that has strength calculation based on caster, which fixes feel of increased resistance in turns with high mechanical grip cars.
But what also changed is gyro not acting as a SAT damper anymore, when it was resisting wheel quickly snapping back after understeer slip.
It might not be an issue if your wheel or settings use high damper already as it more or less might take care of that to a degree, but those who used to run lower level to preserve details and wheel agility will be affected.
Unfortunately just increasing damper will also affect overall wheel weight, speed, and muffle some details.
Stock Gyro was good in that regard acting as dynamic damper that was not always ON.
Good to see some development there, but afraid it needs more tuning for wider audience, including DD owners.
I know from how the code actually works that a lot of what you’ve mentioned is just placebo and some is just misinterpretation of what’s going on.

The original KS gyro used the wrong inputs to the gyroscope equations, it’s physically incorrect almost all of the time. All this change does is fix/replace the equations and give them meaningful scaling (via “caster”, which isn’t really caster but that’s irrelevant at this level) instead of the arbitrary scalar used by KS.

So in terms of you asking for the effect to get adjusted, there’s nothing really to adjust about the effect itself besides force magnitudes (dependent on suspension geometry - might come later). It’s entirely physics based, so if something is wrong, it’s almost guaranteed to be an issue with the ffb as a whole, not this specific part.
 
  • Deleted member 197115

Don't know man, just telling what I can reproduce repeatedly with it on and off, so placebo is out of question, it's just too obvious.
If you have SC2, I can share my settings and you can try it yourself.
 
Don't know man, just telling what I can reproduce repeatedly with it on and off, so placebo is out of question, it's just too obvious.
If you have SC2, I can share my settings and you can try it yourself.
The " fixes feel of increased resistance in turns with high mechanical grip cars " is placebo (the "caster" multiplier is going to be very close to what the recommended settings were for the first version of extended gyro in cornering situations, so it'll feel the same), the rest is just how it is. Like I said, the KS gyro effect is just not correct, so any comparison to it doesn't make much sense.
 
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  • Deleted member 197115

I think even Stereo's description in OP is pretty accurate on what exactly is missing now, or at least my own interpretation matches experience.
Right here.
Concretely, what we're talking about here is oversteer - on the original experimental gyro, the force acts counter to self-alignment during oversteer. With this new implementation, self-alignment is allowed to occur freely, or, if the oversteer is so quick that the wheels can't self-align, it'll actually push in the direction of alignment.
And this is exactly the problem, it does it too quick now, creating that snap back effect even after understeer as nothing counters self-alignment force.
I will wait for other Simucube users to test and chime in.
The easiest way to reproduce is by using these settings, perhaps even drop Damper to 5% as it does not have to be that high with stock Gyro on that car.
Take KTM XBow to Zandvoort, initiate aggressive turn in with some tire slip and let wheel go with little to no assistance after tires start gaining traction after understeer causing wheel self align. With stock gyro it gets slowly returned to the center position, with new gyro it violently snaps back and even overshoots if not stopped.
The difference is just too obvious and strong to miss.

I think that was my last post on the subject, switching back to stock "wrong" gyro and moving on with my life.
 
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I think even Stereo's description in OP is pretty accurate on what exactly is missing now, or at least my own interpretation matches experience.
Right here.

And this is exactly the problem, it does it too quick now, creating that slap back effect even after understeer as nothing counters self-alignment force.
I will wait for other Simucube users to test and chime in.
The easiest way to reproduce is by using these settings, perhaps even drop Damper to 5% as it does not have to be that high with stock Gyro on that car.
Take KTM XBow to Zandvoort, initiate aggressive turn in with some tire slip and let wheel go with little to no assistance after tires start gaining traction after understeer causing wheel self align. With stock gyro it gets slowly returned to the center position, with new gyro it violently snaps back and even overshoots if not stopped.
The difference is just too obvious and strong to miss.

I think that was my last post on the subject, switching back to stock "wrong" gyro and moving on with my life.
Nick's description is meant to generalize the feeling of what happens in a way that makes sense to the reader without delving into what's actually wrong with the old version.

The actual reality is that the KS formula uses the coordinates of the tire relative to the car instead of relative to the world, which is simply wrong (gives the wrong force direction), and fixing it changes the behavior of the resulting FFB. Nothing more, nothing less. The current one might not be the perfect solution to all FFB problems, but it's objectively more correct for its intended goal than the original version. Whether you or anyone likes it is a different matter.
 
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Oh boy, finally a proper gyro and i don't have a wheel to test it nooooooooooo T_T.

Many thanks to Stereo, mclarenF1papa and rest that made this small feature a reality!! :) :inlove: You guys are great.

@Andrew_WOT What you describe with snap back is the very point of gyro as a physics driven effect, while the Kunos experiment was more to simulate damping in the steering. Both effects supposed to work similarly only on straights and work literally opposite way when sliding.
Also gyroscopic forces can be scary strong. So while i'm yet to test it, what you describe fits exactly what i'd expect it to do.

Anyways modern sims don't simulate most of the damping that happens in real steering, so switching Kunos gyro (which basically was speed sensitive damping effect) to this gyro will feel less like real car from "feel" point of view but will also be more realistic from "physics" pov. It's just that even with best hardware we are still far from true realism that such contradictions can happen.
 
I'm up to 55% on my v2.5 Fanatec and lowered gamma a little to 90 and it feels great for most cars I tested.
A lot more road in hand. This is close to what I am looking for.
But each car feels a little different.
The F40 still feels like an old worn farm tractor.
Also the DRM Revivals are quite dead compared to the RSS GT Pack which are a handful.
 
  • Deleted member 197115

@Andrew_WOT What you describe with snap back is the very point of gyro as a physics driven effect, while the Kunos experiment was more to simulate damping in the steering. Both effects supposed to work similarly only on straights and work literally opposite way when sliding.
That I can clearly see and feel. I am just not completely sold that it wasn't intentional behavior as original Gyro was developed specifically for less dampened DD wheels. Now the behavior for primarily intended audience changed, leaving no replacement option for removed part, except of course sticking to stock Gyro.
I am actually surprised that non DD owners use Gyro at all, if not oscillation and snap back fix, I'd never touch it myself as it dampens some fine details even on DD wheels.
And oscillation should be of a lesser, if problem at all, on slower reacting, naturally dampened belt driven wheels.
Anyway, it doesn't seem like there can be a reasonable solution for both as one removes what the other one needs.
At least we have two options now for different applications.
 
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That I can clearly see and feel. I am just not completely sold that it wasn't intentional behavior as original Gyro was developed specifically for less dampened DD wheels. Now the behavior for primarily intended audience changed, leaving no replacement option for removed part, except of course sticking to stock Gyro.
I am actually surprised that non DD owners use Gyro at all, if not oscillation and snap back fix, I'd never touch it myself as it dampens some fine details even on DD wheels.
And oscillation should be of a lesser, if problem at all, on slower reacting, naturally dampened belt driven wheels.
Anyway, it doesn't seem like there can be a reasonable solution for both as one removes what the other one needs.
At least we have two options now for different applications.
There isn’t an intended audience associated with either...it’s just a physics effect that’s been added to the FFB. One version is physically wrong, one’s physically more accurate. Whether a given wheel needs damping added overall is another question.
 
I guess AC devs would disagree with you on that one.
There’s a significant difference between something being “developed specifically for less dampened DD wheels” and what Aris said. The sentiment from Stefano (who actually wrote the code) was that it would be most helpful for DD wheel users because they would notice the biggest difference, but it was not actually designed for that purpose. If you think Stefano, who hates canned FFB effects, would spend time developing something solely for the DD userbase (0.0001% of users at the time gyro was added), I don’t know what to tell you. It was designed to add gyroscopic precession forces from the wheels to the FFB; a side effect was helping oscillation with DD wheels.

The old gyro may as well have been an entirely canned effect with how it was implemented. Which is okay, it was always labeled as experimental and mistakes happen. You can swear allegiance to that all you like, just be aware of what’s actually going on.
 
  • Deleted member 197115

Lots of assumptions but I haven't seen any other explanation of this feature purpose from Kunos. All I know it was very welcomed and heavily used by DD owners, non DD users usually didn't touch it at all, no need.
I had T300RS at the time it was introduced and didn't start using it until after moving to OSW, it just didn't do anything for me besides adding damper making wheel less reactive.
 
  • Deleted member 197115

All I have found from Stefano is that belt driven wheels should avoid Gyro (software dampening) altogether. If you have any other references, please do share.
Lord Kunos said:
Then there is "Dynamic Damping" (aka "Gyro" in AC1) that is a different kind of damping that raises as the front tyres velocities go up. This is NOT using the hardware damper effect and goes through the normal FF base channel.

Why is damping important and why you should care?
In a real car there is a certain level of damping in the steering wheel due to the friction of the column element and so on.. some of the available simracing wheels have some damping built in the construction of the unit, generally DD and gear based wheels have very low damping while belt driven wheels have much more.
Thus on a wheel with low construction damping it could be useful to add some via software either via "min damper" and/or "dynamic damper".. wheels with lots of built in friction/damping should avoid software damper alltogether.
When driving the effect of dampers is a "stiffer" feeling wheel but also a numb(er?) wheel because the damper is "eating up" microvibrations.

And another comment from Atle
Regarding the gyro, I was told by Aris that the majority of beta testers didn't like the gyro effect, only the ones with dd wheels, so the devs decided to make it an ini file option. Most people with dd wheels will be enthusiasts that know their way around ini files.
 
All I have found from Stefano is that belt driven wheels should avoid Gyro (software dampening) altogether. If you have any other references, please do share.


And another comment from Atle
The Atle comment just confirms that they intended to roll it out for all users but some didn’t like it (maybe because it’s wrong...or something) so they added the option.

I still don’t understand where you’re going with your argument or what your point is besides that you don’t like the new changes. Any friction damping in a steering system is going to be fairly independent of wheel speed. The only remaining “damping” is from gyro precession, which has now been correctly added.

In any case, the code won’t be changed based on user opinion, it’s physics based so there’s no room for adjustability unless the calculation itself is wrong (and it used to be). Friction damping might be added but you may as well do that through the wheel driver anyway.
 
  • Deleted member 197115

I don't want you to see this as an argument, and I am all for positive changes in AC including FFB and definitely do not want discourage you guys from trying to improve on what we have.
My only feedback is that trying to make the feature work for systems it was not intended originally your made it unusable for primarily target audience. You kept Gyro portion but completely cut out "dynamic damping" part.
Throwing the baby out with bathwater kind of situation.

And for damper at driver level, afraid that doesn't work as well as gyro, even at 20% all I get is heavier, muffled wheel with still strong snap back, with stock gyro damper at 5% is all it takes to make it civilized while keeping all the details. I have spent 2 days testing all possible options, damper, friction, inertia, lowered slew rate, none of those can make it feel as good as stock Gyro.
Hope my feedback can help you, if not, please feel free to ignore, as long as stock flavor is still available as an option, we should be good.
Thanks
 
I don't want you to see this as an argument, and I am all for positive changes in AC including FFB and definitely do not want discourage you guys from trying to improve on what we have.
My only feedback is that trying to make the feature work for systems it was not intended originally your made it unusable for primarily target audience. You kept Gyro portion but completely cut out "dynamic damping" part.
Throwing the baby out with bathwater kind of situation.

And for damper at driver level, afraid that doesn't work as well as gyro, even at 20% all I get is heavier, muffled wheel with still strong snap back, with stock gyro damper at 5% is all it takes to make it civilized while keeping all the details. I have spent 2 days testing all possible options, damper, friction, inertia, lowered slew rate, none of those can make it feel as good as stock Gyro.
Hope my feedback can help you, if not, please feel free to ignore, as long as stock flavor is still available as an option, we should be good.
Thanks
We got rid of the dynamic damping because that’s not a real thing...the code in AC was an incorrect attempt at adding gyroscopic precession forces (and that’s all it was! There’s no special dynamic damping section, that effect was simply the result of incorrect code), all Stereo did was fix it. And once again, DD users are not the targeted audience of any of the gyro effects. The code was written (by KS) before anyone realized it would help DD users the most. But like I said, the effect in vanilla AC is simply fictional.

And my point about adding it at the driver level was exactly that...those are the only kind of forces that make sense to add. If they don’t fix your problems, either something *else* in the ffb is wrong, or your perception of what’s correct is skewed. The old gyro made no sense from any perspective other than a hardware bandaid.
 
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11/10 really makes you Feel The Rubber ™.

In all seriousness, Andrew, please, just try some internal friction damping setting or something on your wheel. A bunch of DD wheel users are not reporting what you are, so perhaps their setup is different.
DD wheels have the benefit of not having pretty proportionally large internal damping like gear wheels do; and the downside of not having it. So I believe it really should be added back in via software. I wouldn't be surprised if you just FRICTION = 0 on a real car and it snapped back extremely violently as well.

I don't own a DD wheel though nor drive on one every day so if that matters to you then take it into account.
 
  • Deleted member 197115

Sounds like ACC code is still broken then as it still has both and even renamed it to Dynamic Damping to more clearly reflect feature intent.
Strange move if it was just a bug, don't you think?
https://www.assettocorsa.net/forum/index.php?threads/what-is-damping-in-ffb.55408/#post-1030215
Lord Kunos said:
Then there is "Dynamic Damping" (aka "Gyro" in AC1) that is a different kind of damping that raises as the front tyres velocities go up. This is NOT using the hardware damper effect and goes through the normal FF base channel.
Lord Kunos said:
Infact ACC there is no gyro (it is now renamed dynamic damping because that's basically what it is)
 
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