# [REL] F1 2013 Single Player v1.61 (DX 11 compatible, visors, rain update)

Discussion in 'Vehicles' started by Frenky, Jul 10, 2014.

1. ### FrenkyRegistered

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Hmm will try this in my latest update v1.19, as I already started to upload v1.18 of my mod. And with my upload speed (50kB/s), I don't want to start over again . v1.19 will probably the latest update. I hope that by that time a good F1 2014 mod comes out, so I can make physics for that.

2. ### LgelRegistered

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To Frenky

At first, I wonder how you know that from the figures (0.01, 0.40) the first one is a value of a quadratic function

I was unable to find the formula used by the sim for downforce loss between 0 and 1.5 cm, and I was unable to find an explanation for the 0.01 parameter.

It is an educated guess I made, it is very unlikely that it is a linear function. If you draw a quadratic function you are much closer to reality in my opinion.

Y=ax2+c, where a= 1777,8 and c=(1-0,4) // 40 % downforce loss when bottoming, 60 % remaining.

I calculated the parameters:

Y=1 when ride height = Diff_Limits_Min_Rear_Height, Y=0,6 when ride height = 0.

It gave me this table:

Ride height Downforce loss coefficient
0,000 0,60
0,001 0,60
0,002 0,61
0,003 0,62
0,004 0,63
0,005 0,64
0,006 0,66
0,007 0,69
0,008 0,71
0,009 0,74
0,010 0,78
0,011 0,82
0,012 0,86
0,013 0,90
0,014 0,95
0,015 1,00

I wanted to plot diffuser downforce from bottoming to diffuser limits for rear height.

Because what exactly does "front" and "rear" downforce mean?

I am not an F1 engineer, I do just have some old memories of physics. Your car is a swivel around the CG, when you create physics for a mod you must define aero values that maintain equilibrium between front and rear. If you ignore body aero, you have three downforce vectors (FW,RW, and diffuser) at three different distances from CG.

I suppose than front downforce is from FW, plus or minus part of diffuser (if diffuser center is not aligned with CG), rear downforce is from rear wing plus part of diffuser.

I tuned a 1970 mod (LM Porsche 917, Ferrari 512 S, etc) in RF1, until I had an equilibrium of front and rear downforce i was able to replicate Mercedes looping at will in Mulsanne straight.

Cheers

Alas no RF2 for me until late September, but access to a worksheet and some hdv I copied.

Last edited by a moderator: Aug 2, 2014
3. ### FrenkyRegistered

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Post 1 updated with mod version 1.18. Be sure to download it and have fun racing!
After that I welcome your feedback .

Last edited by a moderator: Aug 1, 2014
4. ### MydriazRegistered

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I didn't know that mod before this release and I must say that I really enjoy it ! Tyres are great !
Thank you very much

5. ### McLeoRegistered

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Anyone know where i can found template of this mod? For develope personal skins. If anyone know, please.

6. ### CoandaRegistered

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Thank you very much Frenky for the latest update. Greatly appreciated!

I have only turned a few sighting laps at Indy with DR TR on medium tyres whilst using a setup I have been working on. Straight away I could feel your changes. More challenging that is for sure. My setup now calls for some more rear downforce on the infield. I might also need to make some further changes to the diff. Early days.

@ lgel. Great analysis and cheers for sharing the data

A couple of questions if I may:-

1. Roughly what is the maximum roll angle a real F1 car would produce? I can't find this answer online.
2. I am trying to setup my 3rd spring dampers. I normally try to have more time on the rebound for the individual dampers. Even with the softest bumps and hardest rebounds I can not produce this. Is that normal for the 3rd spring dampers?
3. Frenky do you have the skills to tackle the centre tyre temp crowning issue? If you did that would be the magic icing!

EDIT ADD: Curious as I am doing some downforce analysis. On one laps in the last RH turn at Indy2014 I had two mass declines in front downforce. Roughly 60%. At this point my ride heights are not low and my throttle % was fairly consistent +/- 0.5%. Any clues as to what would cause this?

Last edited by a moderator: Aug 3, 2014
7. ### LgelRegistered

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To Coanda,

Roughly what is the maximum roll angle a real F1 car would produce? I can't find this answer online.

I don't know, in real world excessive roll would affect tire temps (thru load to outer crown) , aero (diffuser and wings), and weight transfer.

I am trying to setup my 3rd spring dampers. I normally try to have more time on the rebound for the individual dampers. Even with the softest bumps and hardest rebounds I can not produce this. Is that normal for the 3rd spring dampers?

I don't know, if we believe some simple explanation of third springs they work only when both suspension move in the same direction (in straight line to compensate for aero load, and permit softer suspension in corners).

In RF1 I found that they were affecting ride height in curves -which is understandable if you see how they work-, in Rf2 I don't know because until Frenky's work I didn't really try to work on setups.

In my very limited knowledge I tune 3rd spring for straight behavior (not for Fisi which has a different type of suspension). For dampers in RF1 I used damper velocity data that I don't think is available in RF2 at the moment.

With retrospect, I think I always tried to maintain my F1s to low and with incorrect rake until I understood diffuser data.

I had two mass declines in front downforce.

You were driving alone or following an another car?

FWDraftLiftMult=3.50 // Effect of draft on front wing's lift response (larger numbers will tend to decrease downforce when in the draft)

No change of rake visible when this occurred?

May be understeer caused it?

FWLiftSideways=(0.520) // Dropoff in downforce with yaw (0.0 = none, 1.0 = max)

Not near a wall?

Cheers.

8. ### jimcarrelRegistered

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First off, late era f1's and I just don't get a long at all, but this mod has me interested in trying again. It's very good in my estimation. Something about it seems very different from all others I have tried, including ISI's. I can only attribute it to the "physics" that you seem to be trying to bring out in this mod. Very appreciative of your work.

9. ### FrenkyRegistered

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Thank you guys for your feedback, really appreciated.
@Coanda: Regarding the front downforce question. Yeah, exactly what Lgel already told you (thanks for your explanation!). I have to admit, that I forgot to mention, that I actually increased the effect of losing downforce in the draft, especially on the front. It is now 3.50 (from 2.50 I think). I've seen that the CTDP mods use a figure of 4.95, which seem pretty high (also reported by a lot of their forum users). If you were actually in the draft of other cars and/or are able to test it, do you think the effect is too big?
Regarding your question about the roll angle. I honestly don't have figures, but think that it is an area in which my mod could possible improve. Take for example the onboard movie of Hamilton at Silverstone 2013. I'm interested in the slow corners now. If I, in my mod, turn even a Red Bull through the slow corners, than, compared to the onboard movie, it seems to me that I'm a little bit turning an oiltanker. Might also very well my setup or even my driving style/skills. Anyone else think, that the cars should be a little bit more responsive at slow speeds?
Regarding your question about the center tyre temps. Can you point me to the site or forum place, where this issue is adressed? If the problem is "notepad related", there is a small change I could solve it. Otherwise, I think, I lack skills .
@McLeo: I'm sorry, I don't have templates. Maybe Sompir (the mod creator) has?

10. ### LgelRegistered

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Hello Frenky,

Found this info about tires in the car modding section, don't know if you have seen it. //http://isiforums.net/f/showthread.php/19090-Adjusting-wear-rate-doesn-t-work

It is well beyond my reach...

I am afraid that at the moment none of the tires work realistically regarding how spread of temperatures across tire respond to suspension settings (tire model still Wip).

Cheers.

Bye.

11. ### FrenkyRegistered

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Hello Lgel,

Thank you for pointing me to that thread. Interesting read and interesting to read about the differences in TBC and TMG files. I'm still unsure if there is so much wrong with the tyres, exept for the rear temps. However by digging into all the files associated with the tyres I found something not correct compared to reality in the "Trackconfigsbase.ini". For the Silverstone GP it suggests the hard and soft tyres as the human tyre choices. However in reality the choices were hard and medium. This will be solved in the next and probably last update. Changes so far for that update:
* Very slightly increased base drag bodywork
* Slightly decreased base front and rear wing downforce (all cars)
* Slightly increased 2nd order drag from both wings (all cars)
* Drag and downforce only affects cars till 12-13 cm ride height (was 14-15 cm)
* Minor changes on the diffuser. In particularly it uses now a 0.02 "stall function". See post #62 and if interested read http://koti.mbnet.fi/tspartan/gp1975/airoopas/index.php?id=functions.php. I plotted all the functions in separate Excel files (I'm still working on 1 big Excel file). I discovered, based on the functions, that a stall function lower than the "min ride height before stalling begins" results in strange behaviour. Such as more downforce loss at a ride height of 1.4 cm than of 1.0 cm. I therefore suggest for every mod maker to have this value at least as high as the "min ride height before stalling begins" value. On the other hand, changing this value to 0.2 or higher results in a nearly sudden downforce loss at the "min ride height before stalling begins" to a value set by the "downforce lost when bottoming out" value.
* Very slightly increased the human braking power
* Corrected the tyre choice for Silverstone to M/H (was S/H)
* Slightly decreased lift effect of front wing due to drafting (figure changed from 3.50 to 3.00).

I still welcome some feedback before I bring out this update. It may seem quite a lot of changes, but their effect in laptimes in the end is pretty low. v1.18 is still a pretty good version, I think.

Have fun racing!

12. ### jimcarrelRegistered

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Thank you for continuing to dig so deep into the physics.

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Anytime man!

14. ### LgelRegistered

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To Frenky.

I really appreciate the time you have devoted to fine tuning your physics starting on a sound base, I did it with RF1 mods (for my own use) and I know the huge amount of tests it requires before reaching a semi adequate result.

I posted in the general discussion a question that you can may be answer, how can you calculate the position of wheel axles relatives to CG from data in the hdv (to compute leverage of aero devices)?

FWCenter=(0.00, 0.110, -1.51) // Center of front wing forces (offset from center of front axle in ref plane)

Are they computed form [Rear] PushrodSpindle=(0.084835,-0.069897,0.00711) and [Front] PushrodSpindle=(-0.10,-0.150, 0.000) taken from RedBull hdv.

I have an ongoing project of a spreadsheet to help in setting up cars (especially F1) and I am stuck at this point.

At the moment I can't send you any feedback of your new physics.

Thanks.

15. ### FrenkyRegistered

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Nope sorry. I don't know how that is calculated by the game (I haven't found any info on this). In fact, assuming that rF2 indeed calculates with the Center of Gravity (CoG) in stead of the Center of Mass, I even don't know how the game calculates the changing position of the CoG exactly during driving.
If nobody can answer your question, why not send an email to one of the email addresses found here: http://imagespaceinc.com/contact/

I'm really sorry, but some things (also the tyres) still are a mistery to me. On the other hand, I'm slowly starting to understand the shortcomings of rF2. For example, and please shoot me if I'm wrong, it is only possible to describe the downforce and drag levels of wings by a second order equation. Because it is only a second order equation, there is no way to simulate fairly accurate the so-called downforce-to-drag ratio (D/D ratio).
In real life the D/D ratio looks like this (it is in fact a wing of an aircraft, but the line is the same if you read downforce for lift):
http://www.dept.aoe.vt.edu/design/venture/Figures/figure_8.jpg
Especially, the curve at low wing settings can not quite be simulated in rF2. This means, assuming that the drag levels (by comparing top speeds) are oke, that you drive your car at Monza with the lowest wing setting, with quite a lot more downforce, than you would do in reality. And thus in rF2, like in other racing games / simulations, driving with low wing settings at high speed circuits is more profitable than it would in reality. Or did I miss a feature or possibility in rF2?

16. ### LgelRegistered

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To Frenky,

Rf2 cannot be a perfect state of the art simulation, it has to run on actual Pc configurations broadly affordable to the average user (it's not the case at the moment for many users).

You can't expect a sim developed in 2012-2014 to run on the same computers as RF1 in 2005 and in my view it is a very strong limitation to it's diffusion in the current economic situation.

As everything in life it is a compromise, quite good in fact.

I am sure that ISI has better calculation for tires (and many other things), the problem is that they would be to complex to handle by a single PC configuration. Look at a professional simulator, for a single car (the driver) it uses an array of at least five computers (read an article on UK university developed sim for a racing team).

So we must accept it's limitation and enjoy ourselves with it, even if for a dedicated racer it seems to simple, it's complexity is overwhelming for many users.

P.S.

Following Tim's recommendation I bought a nvidia GTX 770 (had to rebuild my 3 year old Pc around, new case, new power font, same mainboard, able to run full graphics, and a totally new experience with a G27 wheel). This setup is out of reach of many people alas.

Last edited by a moderator: Aug 12, 2014
17. ### FrenkyRegistered

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Update news:
I find that some tracks in my mod have rather bad AI behaviour, for example:
on China and Japan the AI is plain slow
and on Monaco and Italie the AI is sometimes crashing in walls or flipping over curbs.
I therefore decided to look for substitute tracks (as I lack the skills and time to improve the AIW of those tracks). I already came up with a better Japan (Suzuka) and Monaco track. Only downside is, those tracks use 2012 DRS rules (so you can use DRS on those tracks everywhere). But those tracks are much better and they will be included in the next update, if and after I get permission from the track makers.
If anyone is able and willing to improve the AIW lines of the tracks in the mod, please let us know. I can upload all the tracks as separate components, if nescessary.

Have fun racing!

Last edited by a moderator: Aug 12, 2014
18. ### CoandaRegistered

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Back from a rF2 break and I thought I would share some data. First thing to do catch up on the old messages.

lgel after further analysis you were spot on. I was in a slipstream. Cheers.

Me too. These day's I keep a heavy eye on sudden loss of downforce. I am still learning abut what the optimal rake angle is and I am sure this is more important now with DRS.

Yes however it could just be my setup. I need more testing on this.

An interesting link: http://www.lolachampcar.com/3rdSpring.html . Different beast for sure. He sure does run his springs allot stiffer.

That is interesting. My understanding was somewhat off. I always knew they were more designed for big brake, high downforce cars however I thought they were designed to control squat or dive under heavy braking or acceleration. I did not think they had such an affect on the primary springs that is until I did this little test today. Here is some data I would like to share with you guys.

This data is taken a mutual resting point once the following rules are qualified:-

'Steering' [%])<0.5 AND
'Brake Pos' [%]==0 AND
'Throttle Pos' [%]==0 AND
'Corr Speed' [km/h]==0 AND
'G Force Lat' [G]==0 AND
'G Force Long' [G]==0 AND
'G Force Vert' [G]==0 AND
'Vehicle Pitch' [deg] <= .05 AND
'Vehicle Roll' [deg] <= .05

I was surprised to see what little effect it had on the pitch angle results at rest and also on track. It does however have some dramatic effects on the Ride Heights & Suspension Position. By the way for those that don't use motec higher values for the suspension position equates to more travel. Same goes for the pitch angle, a higher positive value equates to more dive.

One thing I was surprised and can't explain is the high Suspension Position results in "My Base" test. I would have expected to see them lower than the results in my "Full Soft" test due to firmer 3rd springs and very similar 3rd Spring difference amount. Am I forgetting another variable to consider?

@ lgel I havnt got around to your s.s. yet however I plan to do so over the weekend.

Cheers

Last edited by a moderator: Aug 15, 2014
19. ### LgelRegistered

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Hello Coanda,

First I must confess I don't understand your data about 3rd spring.

3rd spring works mainly when two wheels of the same axle travel in the same direction (so even if it's main goal was to support aero load without a suspension stiff as iron, as you say, they play a role when braking in straight line (less diving of front) or when accelerating in straight line (less squatting).

But look at your ride height in a curve with the same global spring stiffness and widely different 3 rd spring stiffness (I found in RF1 they intervene in ride height, I don't know in RF2).

Optimal rake is just the name of the optimal difference between rear ride height and front ride height for the diffuser to work (was 0,03 in 1.17 of Frenky for RB, was 0 for FISI if my memory doesn't fail).

One of the secondary effects of DRS is to bring rear ride eight up and cause diffuser to lose downforce (good for speed).

Running on 3rd spring is much better than on bumpers.

Some data in the LMP1 from Enduracers for RF1 (quite good physics IMO, you had no 3rd spring defined, and even if the downforce is lower for an LMP than for an F1, you had to run rear springs at aprox 210 N/mm).

So running a rear spring of an F1 at 80 N/mm, and your 3d spring at 200 N/mm, is equivalent in straight line at running your rear springs at 180 N/mm (80 + 200 / 2).

Having an evaluation of downforce on each axis plus weight will give you the amount of suspension travel caused for a given spring stiffness.

If am wrong I welcome anyone to teach me because I am just an amateur engineer.

Cheers.

20. ### CoandaRegistered

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According to this link (http://www.formula1-dictionary.net/rake_angle.html) "But Red Bull use the exhaust gases and their sidepod design more effectively than any other team to 'seal' the diffuser and keep the airflow working through this under-floor area."

@ Frenky - That's ok mate sometime I confuse myself with my own data . It was a simple test whilst stationary to see what effect the 3rd Spring had on ride heights & primary suspension positions. I should have extended this test to on track analysis whilst under heavy loads. The results in "My Base" setup test (which have now been altered) still baffle me a little.

I'm a little confused. That is what this test did. They do intervene as shown in the data.

Thank you I appreciate this additional information.

Its funny you should mention bump/packer analysis. It has been one of my Achilles heals for a long time and something I am interested to understand. How do you work out the vehicle suspension travel range? I presume I if knew this then I am able to see when I am ridding the bump-stops..

I think some time ago we were talking about tyre degradation analysis. Lucky for me Pirelli conducted a secrete tyre test and Dan was busy in the RBR simulator trying to impress and get Webbo's seat so finally I got the nod So I did some and I thought I would share the results.

Jokes aside..

Track: Indy 2014
Car: TR
Starting Fuel: 100lt
Real Road: Private test, preset light rubber with session %.
Test Notes: This test unfortunately was carried out a on controller as my wheel & rig are non operational at the moment therefore the finesse & feedback required to drive these beasts was just was not there. I really had trouble once a tyre went under 35%. Being a clockwise track and with more RH corners I initially thought the LH tyres will hurt the most. And they did however there are 3 high profile curbs that can be mounted very easily particularly on the RHF and in one of my initial tests on soft tyres I was being aggressive and doing this too often. This type of driving really hurt the RHF tyre. Even more so than the LHF. In the following test I drove fairly within the limits and was mainly short shifting 2nd to 3rd. I was not overly happy with my setup. The rake was too high, a little front end understeer, not enough rear downforce for the end of the runs plus for the infield and the brakes were pinching on light fuel loads. That said I manage to get through it. It was not my best driving however it was somewhat ok.

Super Soft: Plenty of grip and to my surprise fairly consistent to the end of the run. I was also surprised just how many laps I could do. I thought I would be in more trouble after 10 laps. I will test this again with my new setup and push a bit harder.
LF: 34%
RF: 36%
LR: 26%
RR: 28%

Soft: As mentioned above on my 1st run I did not respect this tyre enough. It truly got the better of me & I paid for it. On that 1st run the tyre degraded at the same rate as the Super Soft and with less overall grip and not the best setup it was a real handful. On the second run I give this tyre allot of respect and I was mindful of the RF. As you can see from the following data.
LF: 41%
RF: 49%
LR: 33%
RR: 39%

Medium: This tyre is your best mate. A good all-rounder. My favourite tyre. As you can see from the data I spun the car on lap 26 and it hurt my average tyre wear by 6%.
LF: 25%
RF: 33%
LR: 28%
RR: 35%

Hard: I must admit I have not done allot of running on this tyre. Initially to my surprise the tyre felt pretty good and I could almost match my pace on the mediums. About 15 laps into the run I really lost the confidence though as I had some dodgy moments all of them at high speed. My setup didn't help. As you can see from the data I spun the car on lap 20 and it hurt my average tyre wear by 6%. I would like to run this test again with my new setup and maybe place a little less expectation on this tyre.
LF: 25%
RF: 35%
LR: 35%
RR: 40%

Data:-

After this I tweaked my setup addressing some of the issues mentioned above. I may have put a little too much downforce on the rear. I re-run the soft tyre test. I was able to push harder and whilst being on average over 0.5 second per lap quicker. The degradation hit was only 5.3%.

Anyway you may or my not find any of this of use. I just thought I would share my experience..

EDIT ADD: I know we have crowning issues on these ISI tyres. I was unable to get the pressures over 175.

Last edited by a moderator: Aug 18, 2014