Physics thread

[Ameer67]

Great summary @LogiForce! 👍

 

[LeMansAid]

In pCARS we really have a live pure FFB system that continuously works in sync with the other physics systems within the game to provide you that accurate and real feel of being on a road with a car, and you can feel the difference.
So it's not like other games where you have different curbs but all curbs give a perfect sawtooth to send to the wheel. It's not like that at all.

I do love the way you describe the ffb. It makes me wonder if we might be getting to the point where a sim doesn't need a large helping of manufactured difficulty to satisfy the sim tag. I think as we get in to true sim territory, driving will become easier, because it will connect and extend from each person's real life experience. At the moment it is an exercise unto itself.

pCARS feels like pCARS. The others just feel canned in comparison and... just don't compare anymore, sorry....

.... Which is really the point we want to get at really. Nature by itself is a dynamic and organic entity that never stands still, so eventually we will have to work towards recreating such an environment virtually as well.

Makes me think of the Euphoria engine and how even the exact same input (eg. certain push on a shoulder) will yield minutely different results, because that's just kind of what happens in the real world. I suppose until utter perfection can be achieved in physics detail and calculations, somewhat deliberate imperfection might actually be closer to reality. I can't even begin to fathom the number of variables that would act and interact in real life physics.

 

[LogiForce]

I do love the way you describe the ffb. It makes me wonder if we might be getting to the point where a sim doesn't need a large helping of manufactured difficulty to satisfy the sim tag. I think as we get in to true sim territory, driving will become easier, because it will connect and extend from each person's real life experience. At the moment it is a exercise unto itself.


Makes me think of the Euphoria engine and how even the exact same input (eg. certain push on a shoulder) will yield minutely different results, because that's just kind of what happens in the real world. I suppose until utter perfection can be achieved in physics detail and calculations, somewhat deliberate imperfection might actually be closer to the real world. I can't even begin to fathom the number of variables that would act and interact in the real world.

Truth be told, I actually already use the experience I gain from real life driving in pCARS and visa versa. To be honest, I do drive very sporty on the open road with my Lancia Delta HPE (1999 model), which is a FWD car, and whatever I try in pCARS I also tend to try when safe in real life.
For example I try to compare the feedback I get from cornering in real life to that in the game. This led to Andrew Weber (Physics guru) throwing a few tests at me as well concerning for example tyre sidewall buckling and riding on the edge of the tread.

So actually you can already apply real life knowledge to the game and back. Besides, we community members have to do so because comparing Physics to last/current gen sims isn't the right thing to do. Now we can't all drive a Lotus 89T for example, but we can push our own cars to their limits to see how they react and see what we can apply from that experience to the game. While every car does drive differently, certain queues you get are in fact similar. Else we would always have to learn to drive each car all over again from scratch in real life as well, which we don't. We all can easily jump from a VW Beetle into a Porsche 911 and drive off.

How does applying such experience with our family trolleys apply to a monster like a Lotus 89T without making it feel like well... our own trolleys. lol
Simple... pure technical data about the cars we can get from A) The Manufacturer, B) Technical Books and (Haynes) Manuals, C) Magazines and Interviews, D) Racing Teams and Owners... etc.
Everything you can imagine has already been set in stone. Aerodynamics of the chassis, wings and undercarriage, geometry of the car and linkages, size of the rims and tyres, gear ratios, spring rates, fuel consumption, air fuel mixture, the bore and stroke, amount of cylinders... etc etc etc.

Those cold hard facts should in a Physics system based on causality (action->reaction, cause->effect) be enough to reproduce the character of each car, and even each track.
The biggest problem lies in the things that aren't a nice constant, mostly tyre related. Think about the contact patch dynamics, tread dynamics, carcass deformations, sidewall rigidity, flash heating, heating per layer, rim heat, brake hit heating the wheel arch and everything in it.
There are just so many highly dynamic things being calculated at once, especially with the flexi tyre model we have now, that it took us (devs and community) almost the entire project's development time to sort out what actually does what... and what action in one part of the tyre causes a reaction in the other.
In other words, SMS is trying to re-create and make sense of the black voodoo magic that is actually the rubber tyre.

The rest of the Physics changes have been more from going from a linear style approach to a causality style approach in handling things, where possible (we still haven't got a supercomputer at home) and most important.
The only other aspect, choice, is implemented by you the driver with linear or binary inputs. Steering, throttle, brake, clutch and shifter (SQ or H). After each adjustment to your choice on the inputs the Physics system of pCARS will go from that action into a long sequence of continues actions and reactions.

The fact that current Physics systems have been an exercise by itself is mostly likely because most systems do not interact and/or acted in a linear fashion. Something that is contrary to nature itself. After all, once you see something in nature that is straight cut you assume it is man-made for good reason.
Hence all other games, knowing pCARS, to me feel far too canned and directed by the game developer. The cars and environment often do not feel alive.
A reason why people raved about laser scanning tracks. Even if it is a snapshot of the track, the constant flux of nature acting upon the track's surface makes for that the shape, size, angle from every bump, curb and so on differs (even if it is by a tiny amount). This in return makes the track more organic and adds that undirected action into the mix upon which the Physics of the car have to react. However, if the Physics systems do not have a direction relation to one another, there will be little to no behavioral changes to the car. Even if the track surface itself looks and feels correct, the car will not react completely in the way you'd expect it too; making it an exercise by itself, especially with the minimal output from the game to your senses.


All in all, driving in pCARS is easy. Driving a car on the limit though... that is a different task. Personally I find humps the most treacherous of all, as you can't sense (by that elevator feeling) how far the car is lifting off of the ground at certain times. Such a thing just can't be reproduced in a simple home sim rig.
So even with perfect Physics in a game... if you can't sense it than you can't react to it either (causality link missing again).

Anyway, a perfect Physics engine is one that is based on causality in which you with all your senses will be connected. Maybe it sounds a bit like the Matrix in a way, but that's just the way it is... in my opinion at least.

 

[LVracerGT]

I was just thinking about something while daydreaming about the FFB being based off the steering rack like you were talking about. Does it mean that in an open wheel car for example, if you hit the wall it will actually jerk the wheel out of your hands? Or if you're racing side by side in a tin top and make contact it will jerk the wheel if you make wheel contact? This would be amazing!

 

[LogiForce]

I was just thinking about something while daydreaming about the FFB being based off the steering rack like you were talking about. Does it mean that in an open wheel car for example, if you hit the wall it will actually jerk the wheel out of your hands? Or if you're racing side by side in a tin top and make contact it will jerk the wheel if you make wheel contact? This would be amazing!

Technically FFB wise it could do that, if your wheel is powerful enough to overcome the strength with which you hold your heel.

There are two issues remaining though.
The first is we still have sticky walls in place now, as we known from Shift. However, this has been confirmed by devs to be removed.
Second is the fact that I don't think the wheels have their own collisions mesh. Let alone a dynamic collision mesh that changes shape when the tyre changes shape.

If these two get fixed for the better, sure the FFB system is up to it... technically. Your hardware is the limit though.
In any case, I can't promise how much of an effect will be present at the end.

Maybe someone who has spend more time in multiplayer can chip in as to how bumping feels through the wheel? 💡

 

[LVracerGT]

Technically FFB wise it could do that, if your wheel is powerful enough to overcome the strength with which you hold your heel.

There are two issues remaining though.
The first is we still have sticky walls in place now, as we known from Shift. However, this has been confirmed by devs to be removed.
Second is the fact that I don't think the wheels have their own collisions mesh. Let alone a dynamic collision mesh that changes shape when the tyre changes shape.

If these two get fixed for the better, sure the FFB system is up to it... technically. Your hardware is the limit though.
In any case, I can't promise how much of an effect will be present at the end.

Maybe someone who has spend more time in multiplayer can chip in as to how bumping feels through the wheel? 💡

Even if it's not enough to actually rip the wheel from your hands, an effect would be nice, maybe just a quick pull one way or the other just to add to the immersion of making contact. I can tell you from experience (GT Academy banger race) that contact involving the wheels definitely makes you fight the steering wheel

 

[Igano]

Right now it really depends on the car you drive. The Ford Focus RS is terrible for me (according to the devs it's finished). The Lancer Evo was fine, also the Mercedes 190E and the Caterham. I haven't driven all the cars though.

In comparison to AC I prefer AC because they have gotten down better the overal feeling. From what i sense AC is following a simpler approach to ffb where SMS tries to give out more effects through the FFB.

 

[c172fccc]

The Ford Focus RS is terrible for me (according to the devs it's finished).

I'm not sure what you are takling about...Did you made a mistake...

 

[LogiForce]

Right now it really depends on the car you drive. The Ford Focus RS is terrible for me (according to the devs it's finished). The Lancer Evo was fine, also the Mercedes 190E and the Caterham. I haven't driven all the cars though.

In comparison to AC I prefer AC because they have gotten down better the overal feeling. From what i sense AC is following a simpler approach to ffb where SMS tries to give out more effects through the FFB.

Try this instead...

WMD Members only link: http://forum.wmdportal.com/showthre...-quot-Steering&p=656753&viewfull=1#post656753

Save what I wrote in the 'code' section to FFBTweakers.xml in your [My Documents]\CARS\FFB\ folder.
Also disable all 'masks' in the ' F1 menu->Input->FFB Masks' except the top one, leave that one enabled.

I think the cars will feel better now. Equal to what iRacing feels like when you select linear FFB with a 25.0 strength. The only difference in feel is the tyre (or tyre model) used, the rest are cold hard facts that are both used in iRacing (presumably) and pCARS. So data of the car's geometry and (power) steering rack... stuff like that.

 

[doblocruiser]

To the pCars players in here: Can someone tell me how the experience with a gamepad is? Is it comparable with another console racer or is it completely different?

 

[DG_Silva]

To the pCars players in here: Can someone tell me how the experience with a gamepad is? Is it comparable with another console racer or is it completely different?

Ah, something I can answer, as I play with the X360 pad. One thing that the game suffers with at the moment, is the speed at which the tyres overheat, and so you either get understeer or oversteer. This is not a fault with the simulation; if you were to yank the wheel side to side, it would scrub the tyres like mad, so of course you'd end up overheating the tyres. The fault currently lies with the gamepad damping (ie, how gradually the input turns fully left/right when you move the stick), and this is being worked on.

As with everything in the game, this is fully adjustable; you can change the gamepad damping, deadzone, sensitivity and speed sensitivity. It's still not fixed, but it is being worked on. The FFB on the pad is fantastic, you get to feel everything, but the only thing that is missing is the feedback going over small bumps (again, something that has been mentioned, noted, and will be worked on when the game is in Alpha development).

As for how it feels, don't expect the forgiveness and hand-holding of Forza and GT in it's current phase, it's much tougher. But, as all the others have said, please don't judge pCARS in it's current state. To have the access to the sim in it's current state is unprecedented, and we just don't know if this is a normal way of doing things.

 

[doblocruiser]

Hi DG_Silva,

Thanks again for this information. It's good to hear that the pad also gets the attention. I know the game is "Alpha" and nothing will be judged until it's final release. All I read and hear is very promising.

The way it looks right now pCars could very well benefit of the momentum due to failure of others.

Looking forward to further reveals and impressions!

 

[wicken]

Hi DG_Silva,
I know the game is "Alpha" and nothing will be judged until it's final release.

They are still on Pre-Alpha, they aren't that far away now from the Alpha stage.

 

[arthur666]

Right now it really depends on the car you drive. The Ford Focus RS is terrible for me (according to the devs it's finished). The Lancer Evo was fine, also the Mercedes 190E and the Caterham. I haven't driven all the cars though.

In comparison to AC I prefer AC because they have gotten down better the overal feeling. From what i sense AC is following a simpler approach to ffb where SMS tries to give out more effects through the FFB.

One thing I would like to mention: The Focus RS has 300hp to the front wheels, so some crazy ffb to the wheel under throttle might be realistic. The Evo, Benz and Caterham would be much less of a handful as they are AWD/RWD.
Thoughts?

I might go back and drive the Abarth in AC tonite and see if I notice any throttle-on ffb effects. Especially if we get the Hillclimb with the update today!
...sorry, back to the pCARS discussion.

 

[DG_Silva]

They are still on Pre-Alpha, they aren't that far away now from the Alpha stage.

End of April marks the start of Alpha development, so at the moment they are just implementing the last of the features before locking it down. Oddly though, they are ahead of plan on the AI front, so we should have something to report back to you guys soon.

 

[Igano]

One thing I would like to mention: The Focus RS has 300hp to the front wheels, so some crazy ffb to the wheel under throttle might be realistic. The Evo, Benz and Caterham would be much less of a handful as they are AWD/RWD.
Thoughts?

I might go back and drive the Abarth in AC tonite and see if I notice any throttle-on ffb effects. Especially if we get the Hillclimb with the update today!
...sorry, back to the pCARS discussion.

By terrible I mean that it feels like floating and no friction/resistance on the wheel. I change direction and the weight doesn't transfer correctly.

 

[arthur666]

By terrible I mean that it feels like floating and no friction/resistance on the wheel. I change direction and the weight doesn't transfer correctly.

Ah, that is terrible.

I've been watching this game closely. I will buy the pre-release if it made available again.

 

[LogiForce]

By terrible I mean that it feels like floating and no friction/resistance on the wheel. I change direction and the weight doesn't transfer correctly.

There is talk about that, even talks about what settings do what and maybe use some sort of EQ to 'dial in' each wheel to increase linearity and remove as far as possible the initial FFB delay/deadzone which causes a wheel to be a step behind on where it should be.

Currently I use 100% (max) global strength in my T500 driver (others on 100% too and center spring by game (unused by the game, so that's 0% technically)), and 60% in-game FFB strength. Plus a tweaker to disable signal compression around center and disable all 'canned effects' (and to be double sure I also disable all FFB masks in the F1 dev menu to be sure)).

I have driven many cars with that setting. All feel very response and linear and not a step behind. I tried 100% driver global strength and 75% in game strength, but the T500 than starts to overshoot. Going below 60% probably will mean the T500 doesn't respond quickly enough to the physics going on.

Getting quick initial response from the wheel and a linear signal from 0-100% strength versus degrees of rotation will be the key to improve feel.

 

[HeadsoupBob]

To the pCars players in here: Can someone tell me how the experience with a gamepad is? Is it comparable with another console racer or is it completely different?

It's a bit twitchy around centre. But, there's one setting that has quite a substantial effect - running the 'calibrate wheel' option (yes even though it's the x360 pad) and at the 'hold the wheel at 90º' bit set it so it reads between 180 (no input at all, gives a very GT feeling) and 300, that way the lock-to-lock steering is reduced, but it allows far more gradual and finer control. I found with around 300, gampad filter at 100 and steering sensitivity at 0 I could drive the cars quite easily, even the Formula C and Prototypes.

Work still to be done as the default is very twitchy, but the right settings are almost there and I'm sure it'll all be dialled in properly sometime after alpha starts.

 

[VBR]

@LogiForce - It's very interesting reading your posts about the physics & FFB in P-Cars, thanks for sharing your experience. I have a question for you. When I went on a track day once, I was surprised at just how light the wheel on the Caterham 7 Superlight went when going from a standstill to full speed. Also, the weight on the wheel increased when braking into a corner.

My question is this: in P-Cars, especially for vehicles with no power steering, does the FFB get progressively lighter under acceleration, & progressively harder under braking?

 

[LogiForce]

@LogiForce - It's very interesting reading your posts about the physics & FFB in P-Cars, thanks for sharing your experience. I have a question for you. When I went on a track day once, I was surprised at just how light the wheel on the Caterham 7 Superlight went when going from a standstill to full speed. Also, the weight on the wheel increased when braking into a corner.

My question is this: in P-Cars, especially for vehicles with no power steering, does the FFB get progressively lighter under acceleration, & progressively harder under braking?

Yes it does, and this is even more so with the Ariel Atom V8 which is just massively overpowered.

Also I drove the Toyota GT86 today, a test drive at the dealer. Thank god for connections cause I wouldn't drive it if he couldn't sell it normally.
It was my first experience with an FR layout in a sports car. The only other layout was a Nissan Vanette mini-van, which isn't really applicable unless pCARS would get a VW Transporter license or something (like the one they have in Gran Turismo).

Anyways, the biggest thing I noticed is how extremely little (initial) bite tyres have in ALL simulation racing games at low speed (0-100 km/h). Doing the Elk test or Moose test... however it is called in your country, is a near impossible feat to do in sims.
On the other hand the GT86 was really sharp/snappy and responsive with the steering input. It really was a great experience and an eye opener to a point where many sims will have to take interest in, because there are a lot of below 100 km/h turns on circuits. Also having to avoid collisions means you need cars that can pass that damn in-game moose test.

So let's start to throw some mooses () at our virtual cars and see what happens guys. I would love to hear back from everyone at how their experience is with sudden evasive maneavres (moose test) in games and in real life, and how those compare.

 

[arthur666]

Anyways, the biggest thing I noticed is how extremely little (initial) bite tyres have in ALL simulation racing games at low speed (0-100 km/h).

I've always noticed this as well. I always assumed that the difference is in sims, you crank the wheel as much as you like, whereas in reality, it takes some effort (and produces more drama) to turn the wheel enough to produce serious understeer.
I did experience the "Moose Test" the other month. I'm a used inventory manager at a Ford dealership, and (lucky me) get to drive home all types of cars. I was in a 2013 Mustang GT on an Interstate running about 70mph when I noticed a large piece of plywood in my lane. Luckily, traffic was light, I checked my left and swerved a full lane just in time. I remember thinking, "If I had done that in Race '07, I'ld have just understeered and plowed right over the #@&! board."

 

[LogiForce]

I've always noticed this as well. I always assumed that the difference is in sims, you crank the wheel as much as you like, whereas in reality, it takes some effort (and produces more drama) to turn the wheel enough to produce serious understeer.
I did experience the "Moose Test" the other month. I'm a used inventory manager at a Ford dealership, and (lucky me) get to drive home all types of cars. I was in a 2013 Mustang GT on an Interstate running about 70mph when I noticed a large piece of plywood in my lane. Luckily, traffic was light, I checked my left and swerved a full lane just in time. I remember thinking, "If I had done that in Race '07, I'ld have just understeered and plowed right over the #@&! board."

Wow, lucky you. With your job and avoiding the debris.
My dad had to sway a whole lane with caravan once because there was a whole tree on our lane. And even with caravan the car should have enough bite to pull the whole train out of harms way.

So yeah, avoiding anything on track in a game is a royal pain. Which all boils down to this lack of bite in games. It also should make for more precise movements, like when moving out of a slip stream and initiate a take over (it will look more fluid and less abrupt, even with abrupt steering wheel movements).

 

[arthur666]

Wow, lucky you. With your job and avoiding the debris.

Ha ha, thanks, but don't worry. What it gives in letting me drive nice cars, it takes away by burning my eyes with endless spreadsheets, charts, and the fact that most cars I end up having to drive are at best boring, and at worst, dangerous and unretailable.

 

[LogiForce]

Ha ha, thanks, but don't worry. What it gives in letting me drive nice cars, it takes away by burning my eyes with endless spreadsheets, charts, and the fact that most cars I end up having to drive are at best boring, and at worst, dangerous and unretailable.

Can't complain about my ride today...


Foto 17-3-2014 080 by LogiForce, on Flickr

 

[Punknoodle]

Better than mine:

 

[MaDHaX]

I switched over to PC sim's around 8 months ago now, and missed the opportunity to be a part of the early beta tester's. This game sure does look the part but the most important thing is how the physics will feel when playing on a wheel.

I can't believe I cant get in on this project and Slightly Mad Studios is only 5 mins drive from where I live

Maybe somebody would be so kind for me to use their ID to test it out for one weekend?



Is there nobody that can tell us how it feels? Does it feel like any particular game in some ways?

P.S. just read that early alpha starts in April, my birthday is mid april, hint hint

 

[LogiForce]

I switched over to PC sim's around 8 months ago now, and missed the opportunity to be a part of the early beta tester's. This game sure does look the part but the most important thing is how the physics will feel when playing on a wheel.

I can't believe I cant get in on this project and Slightly Mad Studios is only 5 mins drive from where I live

Maybe somebody would be so kind for me to use their ID to test it out for one weekend?



Is there nobody that can tell us how it feels? Does it feel like any particular game in some ways?

P.S. just read that early alpha starts in April, my birthday is mid april, hint hint

It feels like driving a car, and most closely relates to the iRacing feel with linear FFB. Why? Because (CAD-)data on the cars are hard figures. The only grey and black magic area in which there can be a difference is the tyre model.
So a BMW will feel like a BMW, and a RUF like a RUF, a Pagani like a Pagani, and a Radical like a Radical.

What differentiates you from the real thing (apart from tyre Physics) is the fact that you have limitations with your wheel. There are 3 key points that wheel makers need to focus on.

1. Rotational Speed (start speed, stopping speed and return speed... included)
2. Linearity in relation to torque vs degrees of rotation
3. Amount of torque

In most (if not all) cases you will most likely have a wheel that can not match the speed of the real thing, as it will most likely fail in the return speed. In most cases it is either too slow and is always a step behind, or is too fast and overshoots and is also all over the place in relation to the Physics going on.
Secondly your wheel very likely can't match the torque of the real deal.
So what in most cases happens to get the best linearity out of your wheel is that you have more speed, but less torque to achieve the position requested by the game Physics.

So yeah, you can't have the weight (torque) of the wheel but you do have the same feel and feedback of the real thing, just with a bit less resistance.
That is of course unless you choose to ignore linearity and go for more output of your wheel.


So it feels like the real deal but with less 'umpf' through your own wheel hardware, and the tyre Physics aren't like a real tyre as that's Voodoo magic or something. Very grey area and thus hard to get right.

 

[MaDHaX]

It feels like driving a car, and most closely relates to the iRacing feel with linear FFB. Why? Because (CAD-)data on the cars are hard figures. The only grey and black magic area in which there can be a difference is the tyre model.
So a BMW will feel like a BMW, and a RUF like a RUF, a Pagani like a Pagani, and a Radical like a Radical.

What differentiates you from the real thing (apart from tyre Physics) is the fact that you have limitations with your wheel. There are 3 key points that wheel makers need to focus on.

1. Rotational Speed (start speed, stopping speed and return speed... included)
2. Linearity in relation to torque vs degrees of rotation
3. Amount of torque

In most (if not all) cases you will most likely have a wheel that can not match the speed of the real thing, as it will most likely fail in the return speed. In most cases it is either too slow and is always a step behind, or is too fast and overshoots and is also all over the place in relation to the Physics going on.
Secondly your wheel very likely can't match the torque of the real deal.
So what in most cases happens to get the best linearity out of your wheel is that you have more speed, but less torque to achieve the position requested by the game Physics.

So yeah, you can't have the weight (torque) of the wheel but you do have the same feel and feedback of the real thing, just with a bit less resistance.
That is of course unless you choose to ignore linearity and go for more output of your wheel.


So it feels like the real deal but with less 'umpf' through your own wheel hardware, and the tyre Physics aren't like a real tyre as that's Voodoo magic or something. Very grey area and thus hard to get right.

If this game feels anything like iRacing then i'm sure it will do very well indeed, because iRacing to me feels like one of the best sim racing titles out there at the moment.

I just wish I could test it out myself but I don't think it will be that long of a wait until we see the full release now. And if what you say is accurate and there isn't going to be any difference in the physics across all platforms then Turn 10 and Polyphony Digital has alot to be worried about as they have let down alot of fans and general people alike.

One thing about console that could be a problem but we will see in pCARS, is the ability to configure wheel FFB (such as damper and spring settings) and the degree of the wheel. If SMS can do that on the consoles then that will put them at an advantage IMHO.

*EDIT*

One quick edit.

I was just abit curious as I have driven cars with power steering and ones without, will there be a difference with cars that has power steering to the cars that has not?

Also when a car is stationary the front wheels are much harder to turn for example than when you are moving. Will those features of a car be replicated in pCARS?

 

[Punknoodle]

I have a question regarding brake fade - is it simulated in Project Cars? I realise that most cars in the game are ones that probably have really good brakes and don't suffer badly from fade, but for example, the Evo, assuming it has standard brakes (including pads), would probably start to suffer from fairly bad brake fade after being pushed hard for a few laps.