Archive for the ‘iRacing’ Category

Found on the iRacing forums recently. Thanks to David Correia for putting this together and for allowing me to share it with everyone. There is a download-able version at the bottom of the page.

Administrative Chat Commands
- Some commands may be shortened, the bolded part of the commands are the shortest form acceptable.
- <> means a required parameter.
- [] means an optional parameter.
- is the name or number of a driver, same as described above.
- [message] is an optional message to be appended to any admin command.
eg: the command ‘!remove #32 Banning for reckless driving.’ would send out the notification:
‘#32 was removed from the system. Banning for reckless driving.’ to all drivers.

Command	Action
!help or !?	Print list of commands available, or list additional information about individual commands.
!admin [message]	Give other drivers admin privileges
!nadmin [message]	Remove admin privileges from driver.
!remove [message]	Permanently remove a driver from the race, can remove spectators as well
!yellow [message]	Throw a yellow if not already active, issue during 1 to go, to extend the caution
!waveby [message]	Move car up to next lap and send to the end of the pace line
!advance [message]	Advance to next session (qualify to grid, etc).
!chat [driver]	Enable chat for all drivers, If driver is specified, re-enable chat for that driver.
!nchat [driver]	Disable voice/text chat for all drivers except administrators, If driver is specified, disable chat for that specific driver only
!spchat [message]	Allow spectators to chat with drivers.
!nspchat [message]	Disable spectator to driver chat.
!black [time] or [L(laps)]	Give a driver the black flag, Default is a stop and go, optionally specify time or laps to hold.
!dq  [message]	Disqualify a driver from the race, but do not remove them from the server.
!eol  [message]	Move driver backwards to end of pace line.
!clear [message]	Clear all pending or active black flags, dq’s or eol’s for a driver.
General
/#	Send driver priviate message
r	From either the driving screen or the session screen responds to the last person who private messaged you.
/rc	Sends a message to the admins of current event. (/rc is short for race control)
/all (admin only)	Sends a chat message to all drivers even if chat is disabled.
Here is the download-able spreadsheet version	Admin Control List Version 1.00 Last Updated 2010-08-03 List of Admin controls for iRacing Hosted sessions.

Yeah, you could say I’m looking forward to this one.

Cheers,

Shane

Excellent kick start by Doug Gegenheimer, a fellow Mid-South club member.

I thought I’d give it a go to record some of my replays and upload them to Youtube, but didn’t know where to start. I found this on the forum and think it will get me up and running pretty fast.

I capture in FRAPs 1280×720 (full res), 30FPS (this requires you to change the ingame display resolution to 1280×720). To eliminate the choppiness, make sure your replay never drops below 30fps.

I edit the clips in Premiere, and export out uncompressed avi.

I then use VirtualDub to convert and resize the final file.

Things you’ll need:
Virtual Dub: http://virtualdub.sourceforge.net/
Xvid Codec: http://www.xvid.org/Downloads.43.0.html
Lame MP3 Codec: http://www.free-codecs.com/download/Lame_Encoder.htm
VLC Media player (optional): http://www.videolan.org/vlc/

Install all 3.

To convert your video, open VirtualDub. Once open,

- Select File/ Open Video File, to open the file you want to convert
- Select Video/ Compression to open the list of video codecs you can use to compress the video
- In the list on the left, select Xvid MPEG-4 Codec, then click the Configure button
- For Xvid Configuration settings, I use:
Profile @ Level: (unrestricted)
Encoding type: Single Pass
Target Bitrate (kbps): 6000 (5000 min for Youtube “Watch in HD” button)
Everything else I leave alone
- Click Ok twice to return to main VirtualDub window

- Select Audio/ Full Processing mode

- Select Audio/ Compression
- In the list on the left, select Lame MP3,
- on the right, select 48000Hz, 160kbps CBR, Stereo 20KB/s
- Click Ok

-Click File/ Save as AVI to export the video.

If you are using 5.1 or other surround sound modes, you might get an error when encoding starts. I resorted to running the game in Stereo mode so that the fraps capture is Stereo and not surround.

Depending on your system, Windows Media Player can start to choke on the 720p file. I recommend VLC instead, it plays the videos much smoother.

Also, you don’t need to worry about the editing and saving as uncompressed avi in Premiere. Just FRAPs, and convert in VD. You can also use VD to join multiple captures.

G’day Folks,

Dave Kaemmer has written up and excellent explanation of what is coming in tire modeling from iRacing. I’ll warn you now, it’s full of physics and mathematics, however if you want to understand just how difficult it is to get right, you should have a read HERE

If you are new to physics and would like an overview of how it works in relation to racing simulations, I’d suggest reading up on “The Physics of Racing” first. There is a copy here

I’ve been enamoured with physics and how it relates to cars for a very long time and even started writing my own game at one point. The interesting thing is that there is so much that is known, suspension geometry, shock physics, that is straight forward to model. (I try not to use easy) A lot of black box physics engines can do most of that stuff to varying degrees.

The tough part is the tire physics, mainly due to the secretive nature of the business. There is also the fact that a game / simulation will take the tires much further over the edge than even the tire companies test and that is a black morass of fuzzy logic and out of the box mathematics. Why? Well mainly due to the existing formulas for calculating forces acting on a tire at the edge explode in corner cases when they get over the edge making the math get all sorts of crazy.

Have a read of the excellent articles and post your questions. I’m thinking I might dive back into it a little to at least be able to answer questions. There are some open source basic looking physics engines around that I also might have a re-look at to show how it works in code … if anyone is interested of course.

Kind Regards,

Shane

Feel free to drop a comment folks, let me know if you like the guide, what you’d like to see added or if you see something that doesn’t looks right.

iRacing FG01 Baseline Version 1.00 Last Updated 2010-05-14 Starting setup based on real world settings from V8 Supercars.

I still use the Setup Tweak Guide a bunch, but there are things missing from it that are peculiar to road cars in general and the FG01 V8 Supercar in particular.

I’m hoping to work with my Graphically Inclined wife to put together a V8 / Road car tweak guide that is similar but that could be a while off. We are also working on some setup sheets and are working on the V8 Supercar one first.

The baseline setup above is what I use for smooth, intermediate tracks and comes in part from the excellent walk throughs that Neil Crompton gave on the real world V8′s : Part 1, Part 2

V8 Supercar adjustments.

Front Springs

Normal range for the front springs are 500 – 1000 lbs, in 25 lb increments

As well as helping to set the ride height and rake, springs help with mitigating body roll along with the shocks and ARBs. Stiffer springs make for more responsive handling with softer springs helping with grip.

Shocks

A lot of fine tuning is done with the bump and rebound of the shocks on the circuit and teams spend a lot of time with it. What they have that we don’t is telemetry showing where the tires are losing traction.

I have some base bump and rebound settings that feel pretty good. I’ll work on the track, turning laps and looking for things that can be helped. A good example of this is there is a large bump at the top of the rise at Road Atlanta before the down hill to the start / finish line. I was finding the rear jumping out at me, so I have stiffened the rebound to slow down the speed at which the shock comes back. This has the added benefit of helping with hitting the curbs which are a good way to pick up time at Road Atlanta.

Roll Center

We don’t get a front roll center adjustment on the iRacing version of the FG01, however working with all the front geometry to get a good feel is important.

Anti Roll Bars

The front Anti Roll Bar ties the front wheels together and controls how the wheels work together through the turns. Both the front and rear ARB’s are adjustable in cockpit. I like to feel what the front is doing, which means I run a softer front that some. A stiffer front ARB will help when changing direction and initial turn in.
Camber  -6.0

The V8′s run a lot of camber, especially at the front. The default starting point is -6.0. This helps front grip at turn in and through the corners at the expense of stopping distance under braking. I tend to try and get tire temps fairly even across the tires, depending on the track. At silverstone, the long straights give the outer edges time to cool, so tire temps tend to be a little off here. You still need a lot of camber to help through the corners, and the lack of big braking areas mean you aren’t sacrificing too much in braking distance.

Caster

Caster effects the twisting of the chassis as the wheel is turned. Caster rotates the front geometry as the wheel is turned. More caster helps with turning the car at the expense of rear grip. I try to balance the caster with the Watts linkage at the rear to help the car turn through different turns at a track. Silverstone was a good example here as a lot of caster helped the car through the slow corners while letting me run a lower rear Watts linkage that gave better high speed grip at the rear for the fast right handers.

At Road Atlanta, there are more medium speed corners that could use more rear roll center/ higher Watts Linkage, so I reduced the caster so maintain balance through the turns.

Toe In/ Out

Toe In   – helps with straight line stability
Toe out – helps with initial turn in

While a little is good, more is not always better. Excessive toe in/ out will greatly affect tire wear.

Rear Springs 200 – 500

Shocks

Roll Center/ Watts Linkage

Lower   reduced body roll – more traction
Higher increased body roll – better turning

Arb – limit body roll
tries to torque the bar when turning

Camber

Rear camber is usually around -2.0 although I have seen much more camber used on setups. More camber on the rear will help get the car through the corners however it can lead to increased tire wear, reduced straight line grip and reduced stopping distances with the rears locking up easier due to reduced grip.

Ride Height

Front ride height is generally around 3″, much lower than this causes the splitter to hit the ground under heavy braking.

Rear ride height is usually 1 – 1.5″ higher than rear to help the car turn.

Higher ride heights will generate more body roll.

To adjust the ride height adjust spring perch at each corner.

A lot of setups have uneven ride heights right to left due to the live axle moving the chassis under acceleration. Generally a little more right side weight to counter balance the torque going through the drive train.

Rake

Rake is the difference in ride heights front relative to rear. More rake (bigger difference between rear and front ride height) = looser car, Less rake = more understeer. The key is trying to balance the car and be able to control balance during the fuel burn by using the front and rear anti-roll bars.

Due to the heavy nature of the car and the relatively soft rear springs used, rake will increase as fuel burns off. These cars carry around 38g/ 120l fully loaded which is a lot of weight to shift through a fuel run.

This means that the Falcon tends to get looser through the run, especially when combined with rear tire wear.

Tire pressures

Tire acts a spring, with softer tires generally offering increased grip. The aim is to have even tire temperatures across the tires, although this is somewhat dependent on the type of track. A track with a lot of straights, compared to corners will see the outer edges cooling between corners even though the corner grip is correct.

Aim for around 200 f across the tires for optimum grip.

Brake Bias

Locking up the rears usually leads to a quick swapping of ends and the air being filled with expletives. While a rearward bias will help you turn the car getting into the corner, too much will lead to bad things. Something to also take into consideration is that as fuel burns off the rear of the car will have less stopping power and it’s a good idea to creep the bias forward as the race progresses.

Driving Style

Ford Falcon FG01 is a big, heavy under tired sedan. With a live rear axle and lots of power it rewards a certain driving style.

Back the corners up, get it stopped in a straight line before turning in. The live rear end tends to push on corner entry so getting it woed up before turn in is vital in saving the front tires.

Roll the car through the corners feeding the power on gently, again the nature of the live axle is to be tail happy on corner exit, this requires a gentle application of power after the apex and full noise applied once the car is pointed down the next straight.

The rake tends to increase as the fuel burns off which leads to more oversteer through the run. This can be countered by lowering the rear ARB as the race goes on. I tend to lower the rear ARB by 1 click every 6 laps or so depending on how bad the rear tires are being abused. The front ARB also can be stiffened as the run goes although I tend to start it at 5 and lowered it to 4 as the front tires lose their initial grip.

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