Physics discussion thread

Out of curiosity, are you a big fan of AC and ACC? Because both those games, I determined recently are heavily understeer-oriented, which I believe is because people are accustomed to driving FWD cars IRL and because road cars are tuned more for understeer for "safety" reasons. In my opinion, this is the wrong approach.

Are you comparing the front grip in AMS2 in your open wheelers to real world experience, or to other sims?

If you're comparing to real life, exactly what are you comparing? I look at the video of Max you posted and I compare to your lap and I see something almost identical - except that Max is right on the very limit (as you would expect) and he and the car are both reacting to being at that very limit of grip. To me, every single F1 video looks like they're absolutely on rails. With all due respect - I see nothing "wrong" in your video except that you don't look like you're right on the limit. To be fair, finding the limit in the fastest of open wheelers is extremely difficult and I'm nowhere near it myself - hence why I'm racing things like the McLaren MP4/6 and MP4/12C

If you're comparing to your own personal real life experience, are you comparing RWD cars? FWD? How about the quality of your tyres? An old, or cheap tyre will just slide straight ahead, but a high-quality tyre continually tries to "grab" the road as you slide. And I know this, because every single new tyre model I've bought I've pushed hard to find their limits so that I know just how safe I am in my cars. I imagine slick tyres are even better at doing this.

 

Like i said, i’m not an expert.

My real life racing/track days are limited to karts in dry/rain, rallying in gravel and snow and fast road cars with UHP tyres.

I’m very well aware by merits i’m not qualified to say anything about the Pirelli slicks of a F1 car.

AC and ACC - i like them like all sims, but both have their own issues.
The OG AC is complete opposite what AMS2 is.
Way too rigid front tyres because of 1 point tyre contact patch.
And don’t even let me start about the kerbs in that sim.

Best sims to simulate the front tyre grip are IMO iRacing and ACC. In both sims you can really have the front tyres in slip angle, but generally it doesn’t reward you as massively, it’s not as gradual and there is element of danger present.

In ACC, if you overshoot the corner, but manage hit the corner entry and decelerate too fast the front gives up a bit and you lose grip. In that sim the car balance is very important.

In AMS2 in the same situation the front just finds grip magically and starts rotating.

 

The thing is you are driving quite slow with very blunt inputs, in the last two corners you are a gear too high and will be very slow on the main straight. Why it seems like the car rotates indefinitely is cause you scrub off speed and generally arrive at low speed into the corner How many laps did you do consistently with that kind of driving, I think not many. I don't mean to be mean but the driving portrayed there lacks a lot off stuff, you don't load the front very well, inputs lack in amount, precision and timing. Generally that is not nowhere near the limit and driving like that wont' get you there, all it will lead to is overheated / dead tyres and inconsistent driving experience. Try going at 70% pace and gradually speed up when you start feeling the car, It will change your perception when the limit gets closer.

 

Did you read the previous comments? I'm demonstrating the behavior, not driving at any kind of pace.

 

But it's like I said as well - if you're not driving on the limit you're not going to be inducing understeer. You can't compare that to Max's pole lap where he is 100% on the limit

 

What strikes me is that the accelerator pedal acts as a kind of on/off switch, which is particularly noticeable when exiting corners. Normally, TC intervenes if you accelerate too early, which is what I experience in other sims, but in AMS2 this results in sudden oversteer or sliding. I tested different sims and the same car and track in AMS2. Are there others who have had this experience?

 

I have had to turn the accelerator responsiveness down a fair bit within the ams2 control settings.
On default settings I have always found it way to sensitive on my thrustmaster tlcm pedals.

 

This is likely related to the proper throttle model in AMS2. This is actually because in other sims the throttle model exhibits an incorrect linearity (the torque curve at mid-throttle is just an interpolation between the torque curves at 0 throttle and full throttle). This leads to much higher throttle needed. This is unrealistic, as opening the throttle a _bit_ has much higher increase in actual RPMs than opening it the same amount at the end of the throttle (i.e. going from 0-10% is a much bigger difference than 90%-100% throttle).

 

Thanks for the useful info and I have changed some throttle settings and it feels much better now

 

If you still can turn in more and more mid corner you're just not at the limit of the car. You can also easily spot that you're way under the limit by having to steer to the corner exit (and you apply throttle only after you already coasted through the whole corner). This is not how you're supposed to drive. The corner exit has to be the point where the car is pointing to on it's own because of the forces pushing it into this direction. If you can steer to the exit your corner speed is just too slow.

Just take a look at your T7 (the left out of the infield). You bascially coast the whole corner to the apex. What you actually can do when pushing the car is going full throttle out of T6, only lifting the Throttle for a brief moment to load the front tires for the initial rotation before going back to like half throttle slowly applying to full throttle to the apex. When doing this you will easy feel the understeer on throttle since this corner has a very high risk of going too wide and therefore going into the gravel instead of hitting the T8 curb when pushing the car.
Your last two corners are really bad too, you just coast through both in high gear, instead of going back to like 5th or 4th and really pushing it.

Judging by your time of 1:08,7, I was able able to put down a 1:05,8 quickly with stock setup and I'm not even experienced with these cars since I'm rarely driving them. So I'm sorry if this sounds harsh, but I think your issues are much more coming from underdriving the car or inexperienced driving techniques instead of the games physics. A car that is not at the limit/where the lateral forces in corners at not high enough will course allow unclean inputs and behave accordingly.

 

Like i said 2x already, i was demonstrating behaviour, not driving in limit.

If we talk about laptimes with a modern F1 car, i can hit 1:04 in Spielberg in both AMS2 and AC RSS formula hybrids. And that’s without too much setup tweaking.

Not super fast, but since you wanted to compare laptimes there it is.

My point with my video example and writing is to articulate unnatural behaviour of front of the car in AMS2.
Too many of you start to pick up apart my driving inputs based on that video, where i try to demonstrate the problem.

 

Yes, but you appear to be saying: a) cars behave weird in AMS2 because they don't understeer properly ('the front end [...] has all the grip in the world and I can just steer the front however I wish regardless of inertia.'); b) you aim to provide evidence by showing us driving that isn't understeering properly; c) people point out that the way you are driving isn't going to induce understeer; d) you complain that you're not trying to drive fast and those people are not paying attention. I'm not trying to be facetious, I am just at this point confused.

 

Yeah, not facetious at all, just dismissive and try to frame my feedback as illogical.

It was my mistake to try to demonstrate it with the Formula Ultimate, since it probably has highest downforce/weight ratio in any car in the sim and hence it's hardest car to showcase the behaviour i'm arguing about.
It's still possible to see the behaviour from the video i posted, the physics can be wonky even when not driving at limit.

Just a practical example with actual pace that anyone can try: Take a LMDh car and drive the Flugplatz corner in Nordschleife flat out.
Shouldn't be possible IRL, it certainly is in AMS2.

I've made my case with this.
In the end it's ofc better that other users disagree me on this and can fully enjoy this amazing title.

 

I was not aiming to be dismissive, I was aiming to describe clearly and in simple terms (just for myself!) what I understood to be happening in the discussion, because I am interested in understanding what you are trying to say. I'm sorry if you have been frustrated by the discussion as I have found it fascinating.

I unfortunately also don't really understand why your example of LMDh shouldn't be able to drive Flugplatz flat out, or how that relates to the previous discussion.

In any case I'd be very happy to hear more, but it appears that you are not enjoying this any more, so I shan't pressure you.

 

No offense taken, i just can’t commit more energy to this topic since it’s
1. doesn’t change anything
2. just my view and i don’t want to shove it down to your throats

 

I don't really get your point. Just look at how many tracks and cars we have. It will never ever be possible to match every single corner for every single cars to the real life input the drivers have to make. There also so many factors going into this like road and tire temps, rubber on the road, tire wear, setup of that car, etc that it is hard to match real life footage to a sim. Even sims that only focus on very limited classes can't achieve that.

Also LMDhs don't drive on Nordschleife, so how do you know how their inputs should be? And I have to mention that flat out isn't anything you can use as a reference point since it will surely depend on how close you're at the limit of the car.

This is not meant to be offensive or anything like that, I'm just having problems of understanding the point you were trying to make

 

You are wrong about this. I have seen many examples with Reiza improving physics and other stuff over the years when people have been able to prove that some things are wrong. It doesn't mean the devs come here necessarily to discuss it or it happens quickly.

I have driven that car plenty myself on AMS2 and I really have hard time still buying your arguments of it being wrong with the the material you have presented. It doesn't mean you couldn't be right about it either.

 

Would you be able/willing to post a similar video to before, but this time with 1 or 2 full laps at full racing speeds with everything warmed up and settled in for the car?
Even better would be an additional section that slows a key area(s) down and where you can explain in detail what you are feeling and reacting to?
Holy grail will be telemetry data to back it up, but this is not such an easy thing to undertake and far easier said than done... certainly a nice-to-have.

The slowed-down visual and live description would be extremely helpful, I'm sure.

I get where you are coming from with the above quoted points. However, I totally agree with @GFoyle. The Dev's may not be here adding replies, but they are not blind to it either.

If you are able to show something effectively (even if others don't feel it themselves), they certainly will want to look at it in more detail. If they find something amiss off of your efforts, not only they, but we will all be grateful that you took that time.

Some people are sensitive to things on a car that others are not. Neither is right or wrong... but there may be an underlying cause outside of the players influence that if fixed, will benefit even those who didn't initially recognise it.

All the best
Andy

 

Actually i thought about the full course video and i actually put down a lap another day which i would’ve used as an example. Turns out i can’t/don’t know how to save lap record in practice mode. I needed the save because recording in VR is very PITA and even that small clip i provided to you required embarrasing amount of work.

Why not to drive with a display then?
My rig is designed 100 % for VR use, so i don’t even have display facing me in a rig or any kind of stand/desk for the display in front of the rig.

Sounds like bunch of excuses, but that’s honestly the reason why i haven’t done it already!