Improving rF2 force feedback?

[deak1944]

he (Connor Caple) probably is right on this.
In rF2, the correlation between FFB and LateralVel is about 60%, so one may feel tires' slip. There is no correlation between FFB and longitudinalVel of tires, so there is no way one can feel "slip angle" per se from FFB. If one claims he/she can feel "Slip angle" from sole FFB, that might be wrong. It likely is from collective feels from his brain training on all visual, audio, and hand feels and foot action. Hence one may be sort of as if feel "slip angle", because the longitudinalVel info are fed to his visual and audio sensory.

Since one cannot feel "slip angle" from sole FFB, then one cannot feel a transitioning to "sliding state" --- tires sliding from sole FFB. I personally believe, rF2 did not use a critical "slip angle" to trigger sliding state in their modeling. There might use others such as "GripFract", etc.

I agree that in real life one pay far less attention on FFB feel. Our brain naturally pay more attentions on other feels, such as your body from g-force, visual and audio and foot action etc. FFB feel on hands more or less like is on subconseisous level, instead. It is true on any 3Dof, 4Dof or 6Dof motion simulators. I have 3DoF motion rig. I never thought I need to forcus on FFB feel until I got into that forum. I tried many time to focus on FFB feel to see if I can feel any sliding on my rig. But no way. My sliding feel always from my butt feel on the seat (since my seat is in motion).

How does the wheel feel with the motion rig turned off ? Just as a test?

 

[Led566]

...

Direction change of the vehicle generates a torque on the steering column by load changes. Slip produces a reduction of torque on the steering column, while this is a bit more complicated, but basically and the most simple example is you should feel slip on the steering axle.

...

You are right.
Theoretically speaking steering torque generated by tyres is at minimum in correspondence of the slip angle where the tyre generates maximum lateral grip.
So, when the tyre exceed that slip angle and the car increase sliding, the steering torque increases.
In FFB terms, when entering a corner one should feel in sequence: torque decrease-max lateral grip-torque increase.

 

[Ari Antero]

See this is the fundamental issue with what i'm reading about "realistic" FFB vs whatever else. The settings you posted use the static effects of spring and damper that aren't even connected to what the cars are doing, how does that possibly help you feel the cars better? They're just static effects that don't do anything differently no matter how the car is behaving.

A realistic FFB should be working in conjunction to what the car is doing at all times and should have nothing else getting in the way of that, which is why i think it would give more feedback than a canned FFB. Can you explain exactly what you feel from the cars with your settings? Because i can explain exactly what i feel through all areas with my settings since it connects to the car.

Well, this is going to be hard to explain with my "rally English"

I have never said that your FFB is wrong and I am also aware that my FFB is using static effects of spring and damper.

As I wrote before:"I think that most of us know that contact patch is not ready and ISI has made statement that that we need also new build before new contact patch is going to be released." and what I mean is that it is too early to judge rFactor2 FFB because contact patch and new build is not released yet, we don`t know how it is going to feel and the only thing we know is how it is now.

I own Historic GT car (vette 69) and I have also had opportunity to test other types of historic cars and my FFB is based to this real life feel how steering is when you enter and exit turns/corners, feel of braking etc. I have never claimed that it is realistic FFB everything is based to feel of the car, not how it is connected to the car.

 

[Ari Antero]

Well, if that's what you prefer. Have you at least tried my settings though? You might be surprised by how much you can feel with it.

I agree that the physics are not complete, but it's close enough that the behavior of the wheel is very realistic based on the behavior of the car. Whether the car is realistic or not, really doesn't make a difference if the wheel rotates with the car as it should, the rest is all in the small details, and we're at a point where those small details are just too small for any human to be able to discern from, at least in my opinion. Especially since there are so many variables involved.

yes I did try you FFB, could you post Thrustmaster Control Panel settings also and I give it another go

 

[Domi]

Why do you use overall strenght to 100%? If I recall correctly most linear experience is about 60%.

 

[speed1]

You are right.
Theoretically speaking steering torque generated by tyres is at minimum in correspondence of the slip angle where the tyre generates maximum lateral grip.
So, when the tyre exceed that slip angle and the car increase sliding, the steering torque increases.
In FFB terms, when entering a corner one should feel in sequence: torque decrease-max lateral grip-torque increase.

Basically every load change is transmitted to the steering system, simplest way to illustrate it is when the vehicle is out of alignment, no matter if it has slip or doesn't follow the optimal direction, the straight, even than some forces pulling and pushing at the steering arms.

I'll may come back later to this topic, for now i have to do something and i'm late.

 

[TechAde]

so there is no way one can feel "slip angle" per se from FFB. If one claims he/she can feel "Slip angle" from sole FFB, that might be wrong.

Please take a quick peek at the attached ATLAS grab, from a very quick run on a skid pan with the Skippy. The green trace is steering input, the grey trace is steering shaft torque, the blue trace is FFB output.

It shows there is a clear & obvious drop in steering torque as I crank on more lock, inducing front tyre slip.

Please, can we put this silly idea that "You can't feel slip in the rF2 FFB" to bed now?

 

[speed1]

I remember seeing a graph which showed that it was slightly more non-linear than 70%, and by slightly, i mean a barely noticeable amount in practical terms. It only becomes non-linear at the very tip of the max torque, so you would have non-linearity over a big bump or something, it's not a big deal and you would never notice it. It's better for me at least, to have it set to 100% so that the rest of the torque is there and easily felt.

Exactly why i use 100% as well. It would not recommend to limit the controlers max cababilities because not all incoming forces overload it and drive it to its max limit and it keeps staying fast in response in relation to its starting torque cababilities and overall speed. I don't think that 60% leads to the best torque charecteristic at all. The max torque can be limited with the car multi to avoid clipping.

TechAde let the people the freedom to explain there opinion, it is intresting to hear and know how different people think.

 

[TechAde]

TechAde let the people the freedom to explain there opinion, it is intresting to hear and know how different people think.

If that opinion is based in fact, of course, but when the opinion is blatantly false it does more harm than good if nobody points out that it's false!

 

[speed1]

True that but may they just don't know it better and be teachable.

 

[Mibrandt]

feelings are rarely based on facts and all the graphs and data in the world Will not change how ppl feel things. The ffb of the isi formula 2 car is a good example - its supposed to be realistic according to data but to me it feels totally wrong and weird. Maybe because i have a cheap wheel - g25. Well cheap in rf2 World that is.

 

[Joe]

Please take a quick peek at the attached ATLAS grab, from a very quick run on a skid pan with the Skippy. The green trace is steering input, the grey trace is steering shaft torque, the blue trace is FFB output.

It shows there is a clear & obvious drop in steering torque as I crank on more lock, inducing front tyre slip.

Please, can we put this silly idea that "You can't feel slip in the rF2 FFB" to bed now?

You 100% misunderstood my statements. Please read again very carefully. What I stated:
"In rF2, the correlation between FFB and LateralVel is about 60%, so one may feel tires' slip. There is no correlation between FFB and longitudinalVel of tires, so there is no way one can feel "slip angle" per se from FFB. If one claims he/she can feel "Slip angle" from sole FFB, that might be wrong. It likely is from collective feels from his brain training on all visual, audio, and hand feels and foot action. Hence one may be sort of as if feel "slip angle", because the longitudinalVel info are fed to his visual and audio sensory."

Yes, you can feel slip, there is no argument on this. But NOT "slip angle" from FFB!!!!

 

[Joe]

I don't know what "LongitudinalVel" is but i can feel the transition to a sliding state in rF2 through the wheel. There's always a certain direction that the steering wheel wants to point at any speed, when you turn into a corner, you're actually pulling the wheel away from the direction that it naturally wants to follow, which is simply straight forwards usually, and as long as the tires have grip, you can maintain this turning angle, but once the tires start to lose grip, this immediately effects the steering torque, and just as an easy example to understand:.......

This feel likely from your visual combination, not from FFB. The FFB has no output info of "Longitudinal", all are laternal. Most people confuse about this. Statements like (on stationary rig):

"I can feel slip from FFB" --- True;
"I can feel slip angle from FFB" --- false;
"I can feel sliding from FFB" ----- true;
"I can feel lossing grip: transitioning to sliding from FFB" --- false

Regards,

 

[TechAde]

You 100% misunderstood my statements. Please read again very carefully. What I stated:
"In rF2, the correlation between FFB and LateralVel is about 60%, so one may feel tires' slip. There is no correlation between FFB and longitudinalVel of tires, so there is no way one can feel "slip angle" per se from FFB. If one claims he/she can feel "Slip angle" from sole FFB, that might be wrong. It likely is from collective feels from his brain training on all visual, audio, and hand feels and foot action. Hence one may be sort of as if feel "slip angle", because the longitudinalVel info are fed to his visual and audio sensory."

Yes, you can feel slip, there is no argument on this. But NOT "slip angle" from FFB!!!!

Obviously I am misunderstanding what you mean.

As I understand it slip can mean two things, slip ratio (longitudinal slip aka wheelspin) or slip angle (lateral slip).

Are you meaning one of those two definitions or something else entirely?

My graph shows clearly that as slip angle increases steering torque decreases. I fail to understand how that means you can't feel slip angle.

 

[Joe]

Obviously I am misunderstanding what you mean.

As I understand it slip can mean two things, slip ratio (longitudinal slip aka wheelspin) or slip angle (lateral slip).

Are you meaning one of those two definitions or something else entirely?

My graph shows clearly that as slip angle increases steering torque decreases. I fail to understand how that means you can't feel slip angle.

I do not know how did you get your slip angle. My understanding slip angle is a classic defined Lateral vs Longitudinal.

 

[TechAde]

I do not know how did you get your slip angle.

Sorry, I'm not understanding what you mean at all.

I created slip angle at the front tyres by purposely turning the steering wheel, I mentioned that in my post: "as I crank on more lock, inducing front tyre slip."

Maybe the colloquialism of "cranking on more lock" isn't clear? It simply means I turned the steering wheel, hard, purposely inducing a large slip angle on the front tyres.

Would it help if I added some calculated channels to the plot showing the calculated slip angle of both front tyres?

 

[Joe]

that would be nice if you actually show calculation of slip angle of yours by the data, which may benefit to all.

 

[Joe]

I just explained that it's a range of torque, you'll instantly feel it if you go even slightly over the max turning radius as the car starts sliding from the rear end, since you will feel more torque from the steering at the exact moment that it starts to slide and the transition from "grip" to sliding is relatively gradual, of course depending on the tires and car, but it's gradual enough that you will easily feel it starting to happen before it's too late. It would be possible to feel this even if i were blindfolded and unable to see the monitor, so it has nothing to do with what i'm seeing, my eyes aren't attached to the steering wheel, my reflexes simply cannot be that fast, not unless you think i'm Spiderman.

Just because you don't feel it doesn't mean i can't, or that any good racing driver can't.

I can't really explain it any better, and you don't seem to want to believe it even when you've been shown telemetry which proves that there is a nearly instant change in torque in the steering as changes in grip occur.

OK, you probably agreed:
"I can feel slip from FFB" --- True;
"I can feel slip angle from FFB" --- false;
"I can feel sliding from FFB" ----- true;

but disagreed:

"I can feel lossing grip: transitioning to sliding from FFB" --- false

I may not be able to prove this in either way by using Telemetry data. This is because such "transitioning" is black-art for rF2, since rF2 new tire model dose NOT use the concept of "Slip angle", we really do not know what is a critical point where the transitioning occurs. If you can feel such transitioning from sole FFB, then it is your subjective feel. In motion rig, I feel rear traction loss while rear tires sliding from my butt. Of course, this is subjective feel too.

 

[TechAde]

that would be nice if you actually show calculation of slip angle of yours by the data, which may benefit to all.

Here you go, updated plot attached.

Red trace is slip angle of the LF, orange trace is slip angle of the RF (in degrees).

Slip angle is calculated with the following function:

return (57.2957795 * atan2($LF_LateralGroundVel, -$LF_LongitudinalGroundVel))

Note the 57.2957795 converts the results from radians to degrees.

 

[Joe]

Here you go, updated plot attached.

Red trace is slip angle of the LF, orange trace is slip angle of the RF (in degrees).

Slip angle is calculated with the following function:

return (57.2957795 * atan2($LF_LateralGroundVel, -$LF_LongitudinalGroundVel))

Note the 57.2957795 converts the results from radians to degrees.

Thanks for the charts. Lets look into this deep to understand this.

The correlation between FFB and SteeringShaftTorque is 0.90 (90%)
The correlation between FFB and LF_LongitudinalGroundVel -0.02 (2%)
The correlation between SteeringShaftTorque and LF_LongitudinalGroundVel -0.58 (58%)

So, yes there is some correlation between SteeringShaftTorque and LF_LongitudinalGroundVel, but it does NOT transfer to FFB. In other words, yes you see some correlation between SteeringShaftTorque and slip angle (as calculated), but not the same as seen in FFB.