Physics discussion thread

Ams2 as improved massively over the years. If there were no more improvements to the physics, I would still say the development was a success.

However after reading the comments about tire flex it does help me understand better what I feel is the thing that makes things still feel off.

The transition of tire grip feels muted, I feel it, but it feels like driving with underflated tires. When the cars lose traction and spin and then regrip, there is no sharpness to it as the tires bite. At speed it is difficult to feel when you are on the very edge of grip. Maybe it nothing to do with tire flex but the feeling is comparable to driving irl with low pressure in your tires.

If Reiza can get the 'sharpness' of grip into the sim, that for me would be the icing on the cake.

 

I think that this video showcases very well what is wrong with handling in AMS and I'm not even sure that it's all gamepad related. It looks like, instead of the car making a turn, it rotates around its axis, thus giving it that floating/sliding effect, particularly noticable when cornering. But even on a straight, it's there. If you pay close attention, the steering wheel animation also seems disconnected from the actual steering. It looks horrible.

On the other hand here is a video from RR from the same creator. Although i haven't played RR, the steering and cornering looks like what I would expect it to be.

The difference between the two is like night and day and this is not gamepad gameplay. Over the years the sliding floating effect has been reported so many times, and it's sad to see how it still hasn't been fixed.

Btw this post was written while discussing gamepad gameplay and moved here.

 

I'm sorry but this guys driving skills are just awful. His straight line braking is just some really non-consitent brake pedal pressing, sometimes starting slow and then pressing more heavily, sometimes then just let the brake go completely. And every single corner he's already back on throttle on corner entry.

And on his spin, what kind of reaction time is that? You can easily see where the car lost it's grip very early, but there is just no reaction at all to stop that.

How do you expect the car to drive when you're constantly upsetting the balance of the car with your brake input and already are on full throttle at the apex of a corner? Also the C8 as a midengine car is very agile and therefore more easy to throw off balance. If you're driving technique is not good as you can't pull off proper trailbraking or smooth throttle input out of corners just stick to Aston, M4 or AMG until you're there.

I'm just done with people not knowing how to drive at all being used as an argument how AMS2 GT3s are slidy. As mentioned in this topic many times, please record some laps with Aston on Mosport in a sub 1:16 pace, which any good driver should be able to pull off, and show me where the cars slides at all.

The Raceroom clip only shows that the game allows some very bad driving inputs since the cars are just glued to the ground with understeer even you only use full or none throttle through a whole race as shown here.

Also his FOV settings seems really off and he should turn off all the camera movements he has on

 

The thing is, i've been having blast with AMS2 since 1.6.9 update and i think the front of the car behaves much more realistically than before.

BUT

I 100 % agree on rotating car axis thing. I just drove bunch of low df variant GT3's around Sebring and messed with the setups.
I tried many things to pin down the rear; differential preload, clutches, engine braking and rear anti-roll bar.
While i had success to make the car more understeery, the rear still wanted to lift up in every low/medium speed corner even without any pedal input.
This makes rotating in AMS2 super easy, because you get the generous slip angle essentially in every corner. I've said it before, but it feels like four wheel steering.

Other than that, i believe AMS2 is very deep simulation and i especially love the SETA tyre model.
In my opinion AMS2 could be the most realistic simulator for the consumer market.

Generally i'm not against "slidey feel" and it feels very natural to me, because i drive powerful road cars in winter without studded tires.
The constant on/off gripping is present essentially in every trip at this time of year.

 

Well I made the post in a topic discussing gamepad gameplay. But seeing that the guy in the video, whom I assume is using a wheel (since it's in one of his descriptions), experienced the same issues as I have, I decided to share it. But the post got moved here. However the bottom line is I don't get any of the floating-sliding-rotating effects in ACC nor in RF2. They drive amazing. So I doubt that it is solely a skill issue. I have tried so many things to fix this issue. Car setups, controller sliders, controller input curves, fixed camera. I have just given up. I don't know what the deal is, the gamepad support or the game or both. But I also know that these issues have been reported from people using a wheel.

Look at the turn he makes at 2:00, the car looks like it's going sideways instead of turning then it suddenly straightens out by rotating in its axis, giving it that sliding/floating effect. Super weird. Even with a ****ty driver the car should not behave like that.

 

Agree. Cars rotate around it axis. It's called physics.

 

The point being made was that they suddenly rotate as if they werent being affected by the ground beneath.

 

Cars can slide in all four tyres. It's physics. The nonsense of "slow turns without trottle input" bothers me a lot, because people maybe can't understand If you are traveling in some speed, maybe your rear tyres give up first, it's physics again.

But to get rid of this nonsense of "the car rotates around it axis" (what is ok, by the way, because it's a car, and the old physics thing), a vídeo with turns without trottle input:

And a big thanks for free cam, Reiza! Helps to stop this ethernal nonsense.

 

Just look at his inputs. He brakes like 30% while he is still on throttle, which already SHOULD kill your grip instantly since your front tires will slow down while on the rear the brakes and throttle work against each other.

Brake and Throttle now do a little dance at the same time, absolutely unclear what he's trying to do

Then he decides to drop the brake to go back to ~75% throttle while he turns in on corner entry. You will have absolutely no chance to keep the rear planted by giving it a heavy throttle push on entry.

Think about very basic physics for a a moment here. Want you want to do on this fast corner is give a little brake input to load weigth to the front tires to intitate rotation. As the car rotates you want to transition the weigth back to the rear be applying more and more throttle. By giving the car on corner entry a heavy throttle push he put the weigth of the car all the way back, giving the front tires no grip to intiate rotation. The car was still stable with heavy understeering as he accelerated, since the rear tires had all the weigth and grip. But what follows now is...

..a completely sudden drop of the throttle to zero. That pushes the weigth of the car away from the rear, removing the rear grip, so the rear tires had absolutely no chance and slipped away. He managed to get all 4 tires to slip with this.

And how do you try to catch this? Right, keep turning in more and push full throttle hoping TCS will save you. It's just pure luck the car didn't spin out completely here. Just look at this screenshot.


On the very next corner he already remember what trailbraking is and besides stepping the rear out by going from zero to full throttle instantly the car kept it stable.

So there's nothing wrong with AMS2 here. He did everything to unsettle the car and it did. Other sims let you get away with this unclean driving (see his pedal inputs in Raceroom), but it doesn't mean AMS2 is simulating something wrong here or even having wrong rotation axis.

In a real car you wouldn't survive a single lap on a trackday if that's your pedal input

Also I have get out one personal note on this topic: Please don't fall into the trap of trying to use setups to fix driving habits. You won't need to change anything in any of the GT3G2 base setups to make them drivable or even go against 110% AI. If you really suffer from them sliding away or being "unreasonable" to you, we're all here to help. Record and clips, let us analyse your laps and inputs together and see what the cause is.

Also no pedal input doesn't mean you car is suddenly stable. You can lose grip without pedal input since you're not working with any weigth transfer through the corner. Your pedal input in not there to maintain speed but transfer the weigth between front and rear tires where it's needed.

 

"So there's nothing wrong with AMS2 here. He did everything to unsettle the car and it did. Other sims let you get away with this unclean driving (see his pedal inputs in Raceroom), but it doesn't mean AMS2 is simulating something wrong here or even having wrong rotation axis."

Perfect! Maybe someday people can stop talking nonsense because saw someone saying something without any sense, but with some authority like "I drove a GT something and I don't play this, just that, and this isn't right". AMS2 is better in every update, and is a masterpiece that runs in any potato, even in VR, with amazing visuals, physics, weather and content.

Just some lazy powerslides with some "rotation":

 

Fixing the base setups for me is counter productive, since i quite like the loose rear setups and i’m much faster in AMS2 than in any other sim.
Low 1.59’s with the 992 R in Laguna Seca is just a distant dream for me in other titles.

For me, the excessive rear slip when coasting feels very wrong in a high df cars.
And it’s not just the GT3’s.
With the GT4 Aston in Oulton Park i just loved the feel and feedback from the front of the car, but it felt just stupid how easy it’s to throw the rear around.
From the chase camera it sure looks like the rear lightens and lifts up excessively even when there’s no any meaningful weight transfer.

 

Got a heart attack at the last drift into the pits. ;-)
Interesting to see that tyre pressure is 2.6 bar at the front and 2.7 bar at the rear.

 

Today I noticed a "strange" (to me) behavior related to TC.
I was warming up the tyres in kemmel straight at spa, merc amg gt3 evo, inducing understeer by sharply turning left/right in third gear with mid-fair amount of throttle (70% more or less). Once I induced understeer,the traction control would activate (on hud and dashboard).
It seemed not to intervene in cutting power,as expected,because rear wheels were not breaking traction at all, but the tc lights were on.
It seems that tc is driven not only by rear wheel slip but also front wheel slip? Or maybe it's the speed difference between front and rear wheels?but it should not be that much and that fast,and on top of this in that case it should cut power as well...

Maybe this is the same cause that keeps TC lights blinkink also in high speed corners when pushing,without cutting any power since the same corner can be done in the same way with tc off....

I have always been a bit bothered by TC lights veing very very often active...

 

When TCS light is on your throttle input is replaced by a lower value. You don't see it in the in-game input monitor, but with simhub you can read out the throttle input that gets modified by TCS and the Raw input that you actually pressed. so if the lights were on you were running on reduced throttle.

As far as I figured it out TCS in AMS2 always activated at very early slip angle of the car while you're on throttle no matter if front or rear lost the grip. So I agree the TCS in AMS2 is intervening more than it should, but without a separate Slip Angle setting for TCS I get why it's set so sensitive.