Physics right or wrong?

[Frederic Schornstein]

Disclaimer:
First of all please don't make that a fanboy discussion. I always try to be objective and leave my personal preferences out of the way. I am always willing to accept, if something I don't like on emotional basis, is better than what I like on emotional basis.

Ok I hope I covered that part and this won't get into a "You are a fanboy of this and that thread".

Prequal:
Like most people I eagerly awaited the release of Assetto Corsa. I read about all the licensed content, loved the screenshots and everything. I didn't drive the tech preview, because I didn't want to get a false impression, because it was all still WIP. The day AC was released on Steam I bought it.
I started really testing it after the first update were the FFB was fixed.

I do really like the game and wanted it to be good and so far my only issue are the physics. Most people praise them and they get a lot of love and I do confess, that in external videos they look great.
The car dives in on the braking, you see all the weight transfer and everything. No other sim offers that!

Example:
But as soon as I drive it, it feels just so wrong to me. Just one example: I tested the BMW Z4 GT3 at Monza. I know the track very well and usually drive GT cars, so a perfect combination for me.
Despite all the massive understeer you get everywhere in AC even with setup tweaks, I wanted to point out something you can judge on a much more objective level. So I will talk about the braking distance.

Every racer knows how hard the first braking zone in Monza is. You have a low downforce car and arrive at 260+ kph and have to break down to 60-80kph. So if you look at a lot of GT3 onboards on youtube even with cars, that do have ABS and are a bit restricted due to BOP. They all break before the 200meter board.
That said, I can brake at the 300meter (270kph) board and have the car at a total stand still at 150meters. If I brake for the corner I can brake at or after the 150 meter board.
So we already have a 25% shorter braking zone compared to a real life car with equal or less power and ABS, which I didn't use.

Test conditions:
So now people would start arguing, that I maybe run more downforce and stuff and that is the weirdest thing. I tried to figure out the "worst" braking performance. I used hard tyres and removed all the downforce from the car for this test.

I don't want to get to much into the details of the cornering behaviour and the understeer and that you can just pull on tons of lock and don't get any turn-in oversteer.

Is my opinion qualified?!:
A lot of simracers don't have a lot of reallife experience and I didn't race a GT3 car in my life, but just a quick background:

I drove Race07, rFactor1 and now rFactor2 and I am a pretty good driver in rF2 especially in rear wheel drive touring or GT cars. Even in the new Civic I was racing for wins after 30mins on an unkonw track, so I can quickly adapt to new cars and tracks etc.

In my free time I did some kart races with friends and even on an unkown track with for me unkonw more powerful karts than the average rental karts on a bit cold track I got within 1,9 seconds of the track record within 15min and reduced it to 1,5 seconds in a further 15min.
Keeping in mind that real professional Kart drivers practice their and I had maybe 2 or 3 hours track time in karts ever, I would say I am not a bad driver.

So when I jump out of rF2 into a kart it just feels like home. I apply nearly the same technique and everything. When I jump into AC it all feels wrong. It is so hard to get wheelspin. You can turn the wheel so much, that you would end up in a wall in real life.

I also spoke to some guys with actual racing experience and they got the same feeling.

The end:
I really wanted AC to be a very good sim and I do love everything about it, but these physics keep me from driving it.
In a sim I don't want it to be easy, I want it to be as realistic as possible, but in AC you can apply some really bad driving technique to get quicker laptimes.

 

[Stelios]

As designed

Imagine if you had just spent 1.5m Euros to buy that pos !

 

[Radek Zukowski]

Well, EInstein is a large dog,,,woof woof....common bark with me: WOOF WOOF.....that's right my boy. And as i steer Einstein starts barking WOOF...WOOF....nice sound when your doing turns. I love that dog.

What Einstein has to do with it? Do you think that rF2 uses some algorithms based on special or general relativity, or maybe quantum mechanics?
If you'd used Newton as an example it would make much more sense. Ah, those trolls.

 

[Ho3n3r]

Sry I thought you meant my "real wheel" . Yes I tried it feels a bit weird with no virtual steering wheel

Sorry that I got you wrong after the lot of "unuseful" comments here I thought it was just another one of those

It actually feels, and is, weird with a moving virtual wheel. I can understand having it on FIXED in certain situations, but not moving at all, never.

This way, you will also get out of your head the OCD obsession of having to align on-screen wheel movements to your physical wheel. It's an unnecessary pain, without which you can do really.

 

[Frederic Schornstein]

It actually feels, and is, weird with a moving virtual wheel. I can understand having it on FIXED in certain situations, but not moving at all, never.

This way, you will also get out of your head the OCD obsession of having to align on-screen wheel movements to your physical wheel. It's an unnecessary pain, without which you can do really.

I guess it depends on what you are used to. My driving position is in a way, that I don't really see my wheel, so a virtual wheel for me is great, but at the moment if you want faster steering you have a diffrence between reality and virtual wheel. I hope we get some fine tuning options for that e.g. changeable steering lock.

I tried it for sometime without the virtual wheel, but it is so weird, if you are used to have it for years. I rather look at a virtual wheel that moves to fast than no wheel at all.
If you have a better driving position than mine, it would might be a diffrent story, but my driving position aint gonna change.

 

[Ho3n3r]

I guess it depends on what you are used to. My driving position is in a way, that I don't really see my wheel, so a virtual wheel for me is great, but at the moment if you want faster steering you have a diffrence between reality and virtual wheel. I hope we get some fine tuning options for that e.g. changeable steering lock.

I tried it for sometime without the virtual wheel, but it is so weird, if you are used to have it for years. I rather look at a virtual wheel that moves to fast than no wheel at all.
If you have a better driving position than mine, it would might be a diffrent story, but my driving position aint gonna change.

I get the fact that you're used to it, and if it really your preference, it's great

But for me, it felt like I was watching and concentrating on the on-screen wheel movements a little too much - not a lot, but too much still, and I could use that little bit of concentration it takes up, better on the track.

When I turned it off, it felt weird at first for me too, but now I'm so happy I did it, because my hands feel like they move more naturally now - like I feel the car, instead of watching the car combined with the on-screen wheel.

My seat position isn't in a place where I see it either - but that's OK, as the racing is more about feel than sight when it comes to the steering wheel.

 

[Boby Kim]

T

What Einstein has to do with it? Do you think that rF2 uses some algorithms based on special or general relativity, or maybe quantum mechanics?
If you'd used Newton as an example it would make much more sense. Ah, those trolls.

Dear Radek, i
Last post from me on RD cause i truly had it with people like you Radek. First: you are absolutely right! Im stupid, of course its newton instead of Einstein. But i do not understand why that makes my a troll? By the way, while you are so smart, maybe you can explain in front of the class what a troll is because i do not know, that is how stupid i am. But im very glad that you try to disgrace me in public! Thanks you very much you are such a nice person. I bet everybody in your direct environment knows this. Have lots of love and fun in your life.

To everybody: thanks for the fun and laughter. Bye bye now!

B.K.

 

[Radek Zukowski]

Well, I think you're a troll because instead of trying to do a sensible discussion, your posts look like this:

"Well, EInstein is a large dog,,,woof woof....common bark with me: WOOF WOOF...."
"You could say Einstein is a straight dog. Woof...woof....my gosh, love that sound. Bark boy!"
"Oh Rui...im just a farmer boy knowing how to milk a cow."
"AC: when i turn the wheel, the car follows..."


Also, I didn't say you're stupid, troll != stupid.
Also, I'm not that smart, just interested a bit in physics.

 

[Damien Wintz]

I am not a physics freak but I recently launched netKar Pro again (mainly for Trento Bondone... ) and I have to say, the feeling seems quite different to AC.

I mainly drove the Osella and mid class Formulas and when compared to AC, it just seems much more communicative on the limit. You can basically just "test" the limits of the car multiple times in every corner by giving slight steering inputs one way or the other. It just feels really good. In AC, I cannot seem to get such a precise and instant feedback, the steering feels more "sanitized", dampened in some way.

Maybe it's because of the more complex tyre physics model (dampening from the rubber of the tyre or something in AC...) but I seem to like NKP's feeling better when it comes to steering inputs.

If you look at real onboards it also seems that drivers adjust a lot their steering input in the corner themselves, correcting very subtle understeers and oversteers. It doesn't seem to happen in AC, you can just jam the steering one direction and practically keep it that way for the entirety of the corner, without losing much time.

I know this post isn't very scientific, I just wanted to express my feelings about both titles.

 

[Rui Santos]

I am not a physics freak but I recently launched netKar Pro again (mainly for Trento Bondone... ) and I have to say, the feeling seems quite different to AC.

I mainly drove the Osella and mid class Formulas and when compared to AC, it just seems much more communicative on the limit. You can basically just "test" the limits of the car multiple times in every corner by giving slight steering inputs one way or the other. It just feels really good. In AC, I cannot seem to get such a precise and instant feedback, the steering feels more "sanitized", dampened in some way.

Maybe it's because of the more complex tyre physics model (dampening from the rubber of the tyre or something in AC...) but I seem to like NKP's feeling better when it comes to steering inputs.

If you look at real onboards it also seems that drivers adjust a lot their steering input in the corner themselves, correcting very subtle understeers and oversteers. It doesn't seem to happen in AC, you can just jam the steering one direction and practically keep it that way for the entirety of the corner, without losing much time.

I know this post isn't very scientific, I just wanted to express my feelings about both titles.

Put this post in Assetto Corsa forums...

 

[Damien Wintz]

There's already a thread on that, with good arguments on both sides. Some people seem to prefer AC's feeling, but it's hard to tell which is more realistic without actual telemetry data (including steering inputs).

http://www.assettocorsa.net/forum/index.php?threads/netkar-pro-versus-ac.4137/

Now I remember that NKP suffered from pretty bad exploits (search for hotlaps on youtube, you'll see what I'm talking about...), and AC clearly seems like an improvement on that side. AC's biggest issues might be related to the lag that seems to be happening between the computation and the rendering, hence the less "direct" feeling, and lost "precision" in the inputs.

 

[Pawel Ziolkowski]

There's already a thread on that, with good arguments on both sides. Some people seem to prefer AC's feeling, but it's hard to tell which is more realistic without actual telemetry data (including steering inputs).

http://www.assettocorsa.net/forum/index.php?threads/netkar-pro-versus-ac.4137/

Now I remember that NKP suffered from pretty bad exploits (search for hotlaps on youtube, you'll see what I'm talking about...), and AC clearly seems like an improvement on that side. AC's biggest issues might be related to the lag that seems to be happening between the computation and the rendering, hence the less "direct" feeling, and lost "precision" in the inputs.

I wonder how much "precision" is there IRL actually. At this point i believe a well set up sim gives more feedback through steering wheel than what real racing drivers get. The g-forces there make all the difference.

Until we get an force feedback seats, its really about striking balance between realism and giving enough feedback to the player so that it's possible for him to control the car to the same extent as IRL. For example of this AC already implements things like wheel slip rumble effects, because we can't really feel the wheels slipping on a screen.
Yes it's not an realistic effect but it does allow us to control the car in a more realistic way.
The same would go with precision feeling.

I would agree that AC has less precision than in NKP (or some other sims). But at the same time it feels more "right", just like you would expect real car to behave. Even thou it's harder to actually feel the car at the limit.

More OT

We are so close to "realism" right now that we should drop the "right or wrong" and focus more on hardware. That is wheels, CPU/GPU/screen configurations and limitations. The right setup can make all the difference!

On that note the lag that Damien mentions could be a product of hardware problems and the fact that AC physics engine runs only at 50hz.
50hz is kind of low number and when there are other problems it might just amplify them.
edit: looks like it's unconfirmed/wrong info

 

[Stereo]

I wonder how much "precision" is there IRL actually. At this point i believe a well set up sim gives more feedback through steering wheel than what real racing drivers get. The g-forces there make all the difference.

There's quite a lot of opportunity to lose precision IRL really. The steering rack can be a bit loose, any of the connections up to the wheel hub can be loose (the ends of the tie rods need some form of bushings). More importantly there's a lot of flex in the tires. Less so with low-profile tires, but the contact patch can still move from side to side as load is put on it. All of these would exaggerate how much you need to saw the wheel back and forth to make a given amount of adjustments.

It's of course also to keep in mind that the wheel's not exempt from G forces. When your car hits a bump, you'll feel the movement in your hands - not turning like FFB, but bouncing up and down. Removing that type of feeling from steering inputs is gonna make it feel different cause the wheels just don't have those degrees of freedom. Running across a curb in a well setup car isn't going to push forces through the steering rack, but you will feel the bouncing in your hands.

I do have issues with the way AC tells me about oversteer, but I've never driven that hard in a real car so I don't know what the wheel-feeling should be. I mostly pick up on it by watching the track carefully as I corner, and knowing the situations when it happens. Other games have made the FFB tell the story a lot better (LFS comes to mind) but I don't know if that's realistic or just compensating for other missing forces.

 

[Michael Hornbuckle]

On that note the lag that Damien mentions could be a product of hardware problems and the fact that AC physics engine runs only at 50hz.
50hz is kind of low number and when there are other problems it might just amplify them.

Link to this fact please.

 

[mclarenf1papa]

Link to this fact please.

LOL.

I'm wondering how the physics engine can possibly run at 50 hz if our FFB wheels get information at over 300 hz (some even closer to 900)....

 

[William Levesque]

I do have issues with the way AC tells me about oversteer, but I've never driven that hard in a real car so I don't know what the wheel-feeling should be.

What I'll say depends on having a car with good steering feedback, so considering this:

You will feel understeer through the wheel, it'll get looser as you turn in. In most cars it isn't in your face though, it's more subtle, but still noticeable.

Oversteer however you won't feel it through the wheel, since the front wheels aren't really affected by the back end stepping out. You'll feel it once you are sideways and the wheel wants to straighten out, but not before. You'll feel subtle changes of rear grip through your butt mainly, and instinct depending on how well you know your car.

 

[Chris]

I'm surprised this thread is still going... Atleast it's back on topic

 

[Michael Hornbuckle]

What we've learned so far:

Assetto Corsa uses a simplistic tire model with physics running at 50hz yet somehow feels closer to driving a car than any of its far more sophisticated tire model using competitors. And something about a dog named Einstein.

 

[Pawel Ziolkowski]

Link to this fact please.

Hmm there was quite big thread on AC forums, (here: http://www.assettocorsa.net/forum/i...-jittering-motion-when-rendering-at-60hz.3756)
Now it looks locked, with a reply that the physics run infact with higher speed. Unfortunately I can't find any more detailed dev-posts on the matter. (i would swear i saw a devpost somewhere a month or so ago)

So it looks like it was false claim sorry.

 

[Requiem84]

I am not a physics freak but I recently launched netKar Pro again (mainly for Trento Bondone... ) and I have to say, the feeling seems quite different to AC.

I mainly drove the Osella and mid class Formulas and when compared to AC, it just seems much more communicative on the limit. You can basically just "test" the limits of the car multiple times in every corner by giving slight steering inputs one way or the other. It just feels really good. In AC, I cannot seem to get such a precise and instant feedback, the steering feels more "sanitized", dampened in some way.

Maybe it's because of the more complex tyre physics model (dampening from the rubber of the tyre or something in AC...) but I seem to like NKP's feeling better when it comes to steering inputs.

If you look at real onboards it also seems that drivers adjust a lot their steering input in the corner themselves, correcting very subtle understeers and oversteers. It doesn't seem to happen in AC, you can just jam the steering one direction and practically keep it that way for the entirety of the corner, without losing much time.

I know this post isn't very scientific, I just wanted to express my feelings about both titles.

So what carso you exactly compare?

Obviously, the Osella, FF's, Ftarget etc will feel MUCH more precise than any given roadcar in AC.

For a fair comparison, I think we should compare the Formula Abarth to the F2000 in NKP

 

[Deleted member 151827]

The way i see it is this.............If i have fun with the sim the physics gotta be right! Some here way over think this stuff. lololol