Physics discussion thread

I can't understand how this sim still doesn't have a proper sense of weight transfer. Even in softer sprung cars you can set the springs (and dampers) to minimum values and there is no sense of the weight transferring to the front or rear. The car feels completely rigid. This probably has a lot to do with why you have to drive it in weird ways, because you can't feel the weight on the nose or the rear of the car. Without this issue being addressed in a proper way, AMS2 will always have issues. Tire model may have its own issues (good and bad) but the inability for the car to transfer weight, or at least relay that to the player means you aren't driving something like a car at all.

 

Not my experience at all .

 

About weight shift:
I drive with Reiza's recommended FFB settings for the CSL DD 8nm (Fanatec app and ingame) and have a very nice feeling of what the car is doing. I use default FFB (had been using default + for quite some time but reverted back to default a couple of months ago because default + felt a bit too informative).

@Sejourner82:
Try to set up your wheel so that you can feel when the outside front tyre starts to roll while cornering (Curva grande at Monza ot the long right hander at Barcelona). It's a very distinct feeling. It occurs when the tyre starts to deform/roll.
If you achieve this feeling you should also be able to feel longitudinal weight shift.
Or maybe it might help to test some custom FFB files (e.g. from Danielkart).

Good luck!

 

Does anyone know why the default setups are so stiff? I feel like default setups really do the sim a disservice and contribute to the slidy/darty nature of the tires and lack of feeling of weight transfer.

It's likely this contributes to divide in opinions about the physics in AMS2. For newer sim racers the stiff settings makes the cars feel really responsive and in control under the limit. However, for more experienced drivers/sim racers the default settings may contribute to the common complaints that the sim feels slidy/floaty/lack of weight transfer.

Of course it's subjective to some degree and I'm sure there are some fast AMS2 racers with the default setups but personally I can't easily push with them using the same techniques I use in other sims. With the setup changes I can rotate the car with the pedals more easily on entry and braking and there's less understeer overall. It's easier to feel what the front tires are doing too when they're not sliding everywhere.

Try making some of the following changes. I'm curious as to what others think.

Soften everything up (decrease tire pressure, springs, rebound rates, anti-roll bar), decrease the engine braking, and decrease clutches and increase preload and coast ramp degrees.

It would be nice if there were two sets of default setups for each car.

 

I think we've officially come full circle if people now complain that the cars are too understeery in AMS2

 

While I do think Gamermuscle is an quite avid AMS 2 hater I have to agree with him here.

I think AMS 2 has made the slip angle much tighter and it really helped a lot, however the core issue is still there if you are a quick driver. During corner entry, especially high speed you never get the feeling that the front tyres actually loads up.

It feels like all the pivoting of the car comes from the center of the car instead of the front and he has a good example of how it compares to a trolley(obviously an extreme difference but it helps explaining the issue) You know you turn the the trolley and all the pivoting comes from the rear casters and the front just rides along.

One expects the front tires to act as the sharp anchor point that digs in and drags the rest of the car around, but instead, it feels like the car is being steered from the middle while the front axle just "rides along" like a set of shopping cart wheels.


AMS 2 is a lot better than it was before and the driving feeling is starting to become really good but I really hope there is a solution to this in the future because I feel like this is the last puzzle Reiza needs to solve with the physics, I feel like its the only true issue left in the driving feeling. I understand it might be very hard to fix this however.

Anyways would love to hear your feedback on this and so happy to see how Reiza is doing really good work right now!

 

He's not an AMS2 hater, as his praise for Reiza in the video demonstrates. He is giving his opinion on the fundamental physics of the driving.
I love AMS2 it's my No1 sim, but I have to agree with GM, you can use the best Custom FFB file you want to increase the feeling of weight, but it is masking the flaw of the physics. The cars are too stiff, the weight just doesn't move around the car in the way it does in other sims.

 

How can someone not being a hater who constantly says stuff like "cars don't drive like cars, they have huge pyhsic holes in them" and "the most basic part of the handing isn't right". Calling this sim a simcade all the time. And then pulling out the argument that it's a skill issue so only high level players like him will recognize these flaws. Even the whole pivot around the center was disproven time and time again. Just go to replay mode and watch cars from above turn in slowmotion

I honestly don't get why people take someone with that claims seriously when his gameplay is just awful with crashing into AIs left and right and divebombing them where he can. He can't even shift properly shortshifting or slamming into redline all the time... Maybe only pros like him will understand that

It's totally alright to not like a sim. But there comes a point where it's just pointless bashing when you have no real arguments and it's just based on feelings and "I'm a pro"

And again, if you find flaws, nobody will say you are feeling wrong. But if you make bold claims like pivot around center, you should at least show some kind of data like videos to showcase and proof what you claim so people can actually look into that

 

Concealing things isn't a bad thing. Altering something to achieve a positive effect can be a solution for many people; eliminating or reducing flaws—or ensuring they go unnoticed—is a good thing. Incidentally, GM does exactly the same thing with LMU and his app, or with his FFB recommendations. Furthermore, it’s no secret that he dislikes AMS2 and won't be playing it anymore (by his own admission).

 

I honestly don't understand that critique. You / he mean that the front tires would have some infinite grip and never slide at all when loaded? Especially at high speed, unless the car setup and aero is very balanced for the corner, I would find it extremely realistic that front doesn't have infinite grip either (and it's tricky to make a setup like that that works in all the corners of a track that have all sorts of corners)

The one trait that AMS2 does have especially, is that the fronts take over the rear (a lot less now that once, but IMO it's still more than in other sims generally) and it's the rear that starts to slide if anything. So it's kinda weird to suddenly hear about fronts not loading up ...

But if we are comparing to shopping trolleys (and anything like that with caster wheels), it's usually the on throttle rotation/easier to get neutral steering that reminds me of that a bit from mid corner to corner exit. EDIT: didn't mean that this isn't realistic (how easy it is to get on any given car/setup is I guess debatable).

(when comparing to other sims, I think the diff's are setup differently still from other sims where especially by default, the coast and mid corner feel like diff is more locked, understeery (and front weaker so you have to apply deeper trail braking to get the rotation) and on throttle it's more open so you tend to have more understeery behavior instead of on-throttle rotation (LMU characteristics especially).

But sure, AMS2 isn't perfect either

 

Well that's the thing the front rarely if ever slides, now that sounds contradicting considering i said you cant feel the fronts loading up. It's like the front tyres just rides along. I'm not saying AMS 2 is a simcade or unrealistic but you can clearly see it in any cockpit view that rotation comes from the center or rear you never get the feeling that the front are turning the car with the front tyres.


I asked an LLM to really emphasize what I mean and I think its a great analogy.

Most Sims (The Wheelbarrow): To change direction, you have to physically lift the handles and use the front wheel to force that heavy barrow to turn. You feel the weight of the entire chassis resisting you, pushing hard against that single front tire. That resistance is what makes the steering wheel feel heavy and "loaded."

AMS2 (The Hovercraft): The car behaves like it is floating on a central puck. When you turn the steering wheel, a thruster in the exact middle of the machine spins the entire craft on its axis. The front wheels aren't actually forcing the chassis to change direction; they are just pointing the way while the whole body floats and rotates around your seat.

What i'm saying its clearly other people who think the same and of all the sims ive tried only AMS 2 has this behavior.

AMS 2 is not a bad sim, that's not what im saying but I think we should be honest in our critique if we want the sim to be improved.

 

My brain just doesn't perceive it that way and I don't think the view from cockpit makes it seem like that either, unless you are using some of the optional camera movement options (lateral g-force effect, helmet/camera leaning) that might contribute into it.

The custom ffb file I use has very strong emphasis on indication of rear grip (creates lightness when rear get's lose) and pretty front grip and understeer (feels like scrubbing), even to a point where it can feel "less realistic" (subjective what you want, but this file works for me personally but I can drive similarly well with defaults on other good customs too). So when I go to a a corner, it's pretty clear to me always if the car is struggling with front or rear grip or both and where the rotation comes from, does the rear go so light that I get the rotation from that (throwing the rear around a bit in controlled manner), is it with throttle with the outside rear tire pushing the car (more locked diff) or is it mainly from steering input and fronts.

IMO here are some of the things that contribute to this:
1) By default (or by just creating such setup, which can be beneficial for fast lap times on some cases), the rear is more easier to get lose on corner entry (stiffer setup, more open diff on braking/coast maybe some reasons for that), so you get rotation from that (which isn't a bad way to get around corner) and don't even need the fronts to that much.

2) I feel the combined grip of braking / turning might be more limited or "peaky" in AMS2, just a little bit too much and the front doesn't want to turn anymore or alternatively the fronts just take over the rear (contributing to #1)

3) On-throttle rotation is more common as if the diff would be be more locked on power than in other sims by default (or there is bigger difference in the grip levels of the outside and inside tires in such situations).

Now also FFB and camera settings for sure contribute to it as well, at least for some players.

IMO it's generally easier just to get the "rotation" effect in AMS2 than in some other sims where you have to work on it more to get there (but desirable to get fast lap times).

Here is some video's related to this subject

(this one had some interesting comments in discussions early on)

 

I think the front end has both too much grip and is slidy/darty at the same time. It kinda darts and skips over the surface instead of biting in when you're able to properly rotate the car.

You all should try to soften the car setup and tweak the diff to be less locked. I wish gamermuscle would try with these setups changes too since I think it helps mitigate a lot of the physics issues he's mentioning in the video.

Try softening everything up (decrease tire pressure, springs, rebound rates, anti-roll bar), decrease the engine braking, and decrease clutches and increase preload and coast ramp degrees.

With the default stiff setups you can really throw the cars around without feeling much weight transfer.

Like try to purposefully induce a tank slapper.

It's possible but it happens all of a sudden. Instead of feeling a progrssive pendulum like build up of weight transfer it's like the cars are too light and have too much grip until suddenly they do not and the car snaps and slides.

To be clear, I'm not necessarily criticizing the physics here. That scenario and feeling may be realistic with the default setups. It just feels really weird and makes it hard for me personally to push and rotate the car properly like I do in other sims. Once I make the above setup changes then I'm able to drive the cars like I normally would.

 

The issue with statements like pivot around the center is that they are just factually wrong. Just go to any race, go the replay and freecam mode. It's easy to see that cars rotate on the front front axle like they should.

Here's a short showcase, I planted the car directly next to the line so you can easily see how the frontaxle turns while the rear waits planted until it get's pulled into the rotation.

As mentioned in other topics, if you're using Custom FFB you might suffer from smoothed out front tire input. On Standard and Standard+ you can easily feel where the front grip ends on turn in and the resistance get's very light - like it does in real life. With Custom FFB you just steer against an artificial resistance and not the actual tire feedback, so you have no feeling when the front tires lose grip. Don't know why this happens, but that's why I moved away from Custom FFB files after a patch a while ago.

Also check your camera settings, deactivate all movement or even go the the classic mode if the camera movement is throwing you off.

I still don't get how you can talk about all cars at the same time. To me so many cars have such a unique behaviour, that I couldn't even talk about "The GT1 pyhsics" or "The GT3 physics" as whole. There are cars that will deliver more feedback, other will suck up some details. Some cars have huge understeer tendancy, other try to slip away the rear when they get the chance. But no car to me feels like it slips or slides "wrong", each does what I expect the real life counterpart kinda does too. There will always be cars that are a hell of ride, some that feel a bit numb or some as if you're driving in easy mode. I would be great if you could point out specific cars and track where you feel something is off or wrong and - again - it would be great to have any kind of videos showing the issue.

 

Great reply mate!

Camera setting all is off, especially the G-force effects that really emphasize the effect. Regarding FFB is really not the issue however, I think most profiles are quite good, personally I love the rack force one but default is fine too. (Be happy to test your profile as well what it now is)

I usually tweak my setups so I get more aggressive frontend grip and less stability in the rear so I don't have/can lean on it as much as. Usually softer front ARB, harder rear ARB, more frontend downforce, less rear downforce.

The effect is not felt during corner exit or slow speed or hairpins, it's in the high speed corners where you whip the car aggressive in the corner and where you lean on the tyres.

Generally the high downforce cars feel better, like the formula edge and LMP2 feels really good whereas the Audi R8 GT3 feels much worse.

Anyways, thanks for your comment!

 

Usually the content creators don't put a tons of effort to these things and especially don't go back and try some suggestions and somebody like GM, who thinks he is always right, wouldn't ever be able to change his stance on the subject anyway, so it's pointless to try to even argue and convince him (I do agree with some of his critique on diferent sims, but even when he tries to get more positive, it generally ends up being more negative in the end, especially on something like AMS2).

I have used Karstein's latest (rFuktor2 Karsten Hvidberg - Eddie de Beer & Friends Tribute) with some minor tweaks in the file for my taste for many months now. I have used many different files in the past, which I think are good too and I do like the Default as well. I'm personally not trying to get rid of some slidey feeling, I'm more about getting the information I want to drive well and understand the car behavior + have enough effects there for immersion too (like road texture) without those being too prominent.

But back to physics, I really recommned to check this video about AMS2

 

I've been watching GamerMuscle videos since he started, he was one of the very first sim game youtubers and he has a talent for communication. He was sharing his opinions on race sims for years before he'd even passed his driving test (which I'm not even sure he has done). I always start watching and then turn off at the point he starts talking nonsense. I've made it to the end of about three of his videos since 2015. Don't fuss too much about what he says, and he does say a lot.

 

Interesting how he can come to such a strange conclusion about things. I guess its not an actually serious or measured look at the physics/handling but still. Compared to someone like Heusinkveld it's a very different mode of thinking and talking about sim physics. Seems to be mostly vibes.

I also find his take very surprising since he seems to spend so much time in AC. I jump a lot between original AC and AMS2 these days and the feeling and handling is so similar!

 

I’m not sure it’s worth trusting GM’s comments about front tyre loading, given how he famously sets up his equipment with a very narrow steering wheel angle of rotation. I seem to recall it’s something like 180deg total or similarly absurd.

It almost becomes a rudder rather than an object rotating through space due to a force applies at the front of the body creating a moment around the center of gravity causing the body’s motion to arc through space.

He creates a very odd and unique set of circumstances, doesn’t understand why that’s an issue then gets the soapbox out. Not a fan.

 

Why are we listening to a Youtuber who has little to no real life experience driving cars at the track in anger? He did what, one track day in that FWD Toyota Celica? LMAO. The last person anyone should be listening to about realism is Gamer Muscle and other Youtubers with little to no real world experience. Enjoy his content for what it is, entertainment and being a shill for AC.
#IYKYK

In the mean time, enjoy my fastest lap at High Plains Raceway from this weekend.