W.I.P. Goodwood Circuit 0.99

[mantasisg]

Hi, I have started working on Goodwood Circuit this summer. Took a bit of a break after later, and now continuing the project. Track is based on LiDAR data.

A detailed RL tour guide:

A few screens from latest versions

The track also includes wet layout, of which everyone is mad because AC doesn't have physics to suite. You might be sliding out because of too little grip at Woodcote, you might be too safe at Lavant kink. But overall it brings rather nice placebo IMO. The track simulates the need of changing the line as it is when track is wet IRL. It also has puddles with next to zero grip

 

[luchian]

This looks well advanced already, I take it it's not your first track ?

I am all for testing, all kinds of crazy ideas. So voted for trying "wet" track. I guess it all depends on the implementation, and how believable it can be made. If it ends up as a frustrating (instead of enjoyable and exiting) experience, then I'd say it does not worth it. But one must try before that. And when I say try, I mean all the possible solutions for implementing the wet feature.
I guess we should assume from the start that it can't be netKar-like experience, but it could be on some people's liking. I would therefore include it as an option with the help of layouts. Like it ? Fine, go try it out. Don't like it ? Fine, go for normal version. Or better yet provide some feedback and then go for the normal version .

So where is this project now ? Still a long to-do list or.. ?

 

[mantasisg]

No, it is not far off. I think I could rlease it this weekend as ~0.7 version, or perhaps try to work hard for a one more week and release as a bit higher version, maybe ~0.8. To do list is not that long, but not too short either.

It is not the first track I'm working on, but I also haven't reached 1.0 on my few other tracks. I think this will be the first one to reach 1.0 before members meeting in March 2018, if things will go right for me.

As for wet layout. I'm trying to adjust grip levels in a way that laptimes wouldn't be too quick. I like nK rain, but that feels rather flat except that it probably has a few good physics elements, such as contact patch size dependance on speed, I suppose. My approach feels ok most of the time, but at few places feels a bit like ice. On other hand theoretically ice is hydroplaning too. The problem is that if you'd decide to go slow, you would still have same low grip, when in wet track low speed shouldn't reduce the grip too much....

As for TRYING the layout. From users perspective. It is much like trying to watch 40s hollywood movie - the start is slow, you really are just going through it, but the rhythm builds up naturally and soon it is getting more and more interesting. Wet layout is really not for 2-3 quick laps. When in dry you can go flat out after one minute of driving, in wet layout you need to drive at lease 5-6minutes before you find the rhythm and tires generates maximum temps and pressures.

A lot of people will totally dislike the layout because the driving is just too different, you need much more patience. Also I'm introducing different lines in the wet to simracing (not really) - 1/10 will find it out, on racing line it is just too slippery. So you not only have to do totally different inputs but also use different lines.

IRL they don't care as much about tire temps in the wet AFAIK, because high tire pressures is the thing in the rain, as higher tire pressures helps to prevent hydroplaning. I guess wet tire rubber compounds has very low optimum temps. In AC you just take most grippy tire and max out the downforce.

 

[mantasisg]

How to drive in wet layout of Goodwood Circuit in Assetto Corsa



Basics

The very basic thing is to go slow, especially till you get a little bit more temps and pressure in your tires. Additionally till you get in the rhythm. Getting in the rhythm is very important after long time of driving only in the best possible conditions so you would be as high as possible in the fastest laptimes tables. Forget the tables - now you are surviving. You still can use "ideal conditions" and then you'll have something what is just above damp.

1. Madgwick.
2. Fordwater.
3. NO NAME.
4. St. Marys
5. Lavant
6. Woodcote
7. Chicane

1. Brake off line, and aim to go wide. Avoid puddle on the exit and be extra careful when crossing the racing line.
2. Turn in just slightly later than usually, keep the speed low to avoid puddle in the exit.
3. Brake earlier. With some cars it is much better to go wide all the way. Some cars can just slide through the slippery part of usual racing line.
4. Thousand ways to take this curve. You can slowly stay inside. You can shooth through racing line and get grip on the outside, or you can keep outside all the way. Slippery at braking zone.
5. Slightly oily area. Keep of the racing line on entry by going wide. You will also have to go very slowly, because it is very easy to end up in gravel trap. From mid corner to exit stay very very slow, because tarmac is super polished there and rather rubbered. You can try stay in the inside to put the power down earlier or figh the car in more usual line. But don't go totally by the normal racing line.
6. Brake on inside, and stay on inside, midcorner outside is oily, rubbered and polished. be careful on exit as you'll be crossing the racing line, and there is a puddle on the exit apex.
7. better enter slowly, so you could exit quicker and avoid very slippery are with puddles close to the kerb.


How not to do:

Don't start as if it was your usual flat out from the first moment routine, and don't exit when you'll just spin out in the first turn, because you'll be surprised how much slower the ting goes.

 

[luchian]

The approach sounds interesting. Will have to test it to really know how it feels.

The only thing I find a little surprising is this:

Also I'm introducing different lines in the wet to simracing (not really) - 1/10 will find it out, on racing line it is just too slippery. So you not only have to do totally different inputs but also use different lines.

I don't understand why ?
I mean, you already fight with the car, because it's more slippery than usual. But then I need to sort of start a driving quest to discover the "new line" ? Furthermore, in a wet-ish track, the racing line is the first one that dries, so intuition would tell you that "old racing line" is the safest place to be on a wet track.
The only scenario where it would make some sense, is a "track not wet, but with puddles" approach, imo.

What am I missing ? (or do I even understand right what you are saying ?)
And how can I try this wet track ?

 

[mantasisg]

I will probably release tomorrow. Ai work is taking long time today, but the results are OK IMO, maybe AI is just tiny bit too slow.. You will be able to get an idea about lines from AI

I don't know whats the science about drying track, I guess racing line is just slowly switching to normal. And track is drying more over the active lines I suppose, because of tire and car heat and wind which they cause by going by.

The reason behind different racing line is the texture of the pavement, which works very much like tire thread to remove water from the contact patch. Smooth texture is slicks, and rough grooved is semislicks . Soometimes special grooves are made on the tarmac to help removing water, like everything it was pionereed in aviation for runways. You can spot grooves at the grid straight at SPA.

So when the tarmac is used it gets polished and bedrock becomes less deep, smoother texture. Also when a lot of racing is going on a lot of rubber gets embedded into the bedrock, this results in even smoother surface. And finally if some oil leaks then it is terribly slippery.

Now I have to decide is my version 0.7 or 0.8. Maybe tweak a thing or two and release

 

[mantasisg]

Something really special right there

https://www.goodwood.com/grrc/columnists/doug-nye/2017/12/doug-nye-immortalising-period-goodwood-on-canvas/

 

[luchian]

snip

I will have to test it first before commenting more

 

[mantasisg]

Uploaded

http://assettocorsamods.net/resources/goodwood-circuit.118/

I couldn't upload to the site directly, something wasn't working. So I used external source link.

 

[luchian]

I have joined the "new" thread (which gets created when submitting a new resource) with the original thread, so everything is together.

 

[mantasisg]

I think I should do a preview videos for both layouts, but I have to really charge for it, because even 100Mb to upload is a HUGE task for my internet.

 

[luchian]

If you are not in a hurry, I might give it a try. Soon(tm)

 

[mantasisg]

Nah, not really in any rush. It would be huge support from you

If you'd be doing "wet" layout too, then it would be important to use ~correct lines though.

I also had an idea to make a comparison video from both layouts to highlight the differences of driving in them. With dry footage chopped/paused and straights to fit "wet" lap.

 

[luchian]

I've been meaning to ask you a question (feedback from an average user like me ):

Is Goodwood so bumpy IRL also ? I should mention that I have no experience there, not IRL obviously, but also not even in other sims. This is the first time I try this track. The question comes after some testing I have done. For example I was with the Ferarri F40 Stage3 (so going rather fast ), but I was literally almost thrown off the track. Don't imagine something like a bug, I just mean that hitting a few bumps in a series made the (un)balance so pronounced that it was impossible to keep the car on the track.

Does this sound normal ?

 

[mantasisg]

No it doesn't sound normal, but I haven't drove Stage 3 there, only Standard. This version is also a little bit smoother than previous, at something like quarter of the circuit.

Most of those aren't totally bumps, those are more like tiny undulations, but at great speeds they becomes bumps.

I was experiencing continuation when modeling the track, I was learning about undulations from videos, and then from the lidar mesh, and so on. I could have smoothed previous version not enough. But this one should be fine. There isn't much where to go further, unless deleting vertices at great areas where bumps are "not appreciated". I don't want to do that. However, there could be a few bumps of which I don't really find a clue in videos of goodwood. But those are very few, I laso could spot a couple of bumps which seems not to be at my model.

The short answer - yes I very strongly believe that it is quite bumpy.

But it shouldn't be throwing you out. Where was those bumps ? Somewhere around Lavant Kink ? lavant Kink that little left turn in fastest part of the track. It is a bit bumpy there.

Anything similar ?

Will test stage3 tomorrow, I used to drive F1 GTR quite a lot.

 

[luchian]

Very good video. It looks quite bumpy indeed, but I think I felt it even bumpier. I'll try to put up a side-by-side video, it should help clarify this.

Sent from my phone using Tapatalk

 

[mantasisg]

Keep in mind that this guy in the video was about 12-15s off pace I'm free to check S3 mysellf now. I hope it is not so terrible as you are pointing out. I have done millions and millions of laps with a lot of different cars. Before smoothing lavant kink I had to be very cautious with P1 there, but it wasn't too bad. P1 is getting upset in Kunos Nordschleife frequently.

 

[mantasisg]

Now thats a car to test bumps Not even P1 or 911 GT3 Cup comes close. But it wasn't undrivable, but bumps has an impact for pace. Must be very careful at T1 exit which is bumpy. Then there is a bump right before turn in at St.Mary's. Must aproach both carefully.

Standard setup is rather bad. Starting from pressures and ending with brake balance. Pressures in default setup are too low so tire overheats a lot. Toes are very big, so thats not good for bumps. Brakes are too much rear bias, so braking at Woodcote is too difficult. I tweaked those, also increased cambers, and did 1'15'5. The one in the RL goodwood video did ~1'31. Also maybe they have used softer setup, and in AC there is no choice for softer setup.

McLaren F1 GTR is so much more smooth.

After all the circuit is not made for such cars. It is for classic cars befere 70s, also works well as a track day circuit for people with their own road cars.

 

[luchian]

For the sake of comparison, I'll test with the normal F40, not the S3 .

 

[luchian]

So, laps are done, with both F40.
In the normal one, lap time is similar, without pushing, around 1:30 ish.
In the S3 version, you have to go really slow, to be more or less in the same window. I think I did a 1:27 when going slower.

Now the interesting part:
- in the YT video, it's the F40 LM version. Which is quite different than the standard F40.
- in the description of the F40 S3, in AC, the following are written:

The Stage 3 comes with the factory option of modified turbos and boost, to raise the already impressive factory power to over 600 bhp. The car also comes equipped with heavy duty track oriented suspension and slick tires, making this version just a step lower than the all mighty LM racing version.

So.. in the end maybe S3 is the good version to compare the video to .