Weird AI pitstop tactics

[racer69]

I’ve come across two issues with the AI and pitstops in short races this weekend.

The first one is a number of the AI pitting on the second last or last lap of the short races (10-15 lappers around regular size tracks). I assume this is for fuel, is there a way to ensure the AI starts a sprint race with more than enough fuel to need a pitstop?

Second issue was during damp and wet sprint races, the AI is coming into the pits after 5 or so laps seemingly to change tyres, then go back out and complete the remaining 10 or so laps. Are they changing from inters to wets, or is there a way to make them stay out?

I’ve got fuel and tyre wear set to normal, turning fuel use off will I guess fix the first problem, but I’m guessing turning tyre wear off doesn’t fix the second issue?

Thank you in advance, appreciate the help this community provides .

 

[The Iron Wolf]

I’ve come across two issues with the AI and pitstops in short races this weekend.

The first one is a number of the AI pitting on the second last or last lap of the short races (10-15 lappers around regular size tracks). I assume this is for fuel, is there a way to ensure the AI starts a sprint race with more than enough fuel to need a pitstop?

Second issue was during damp and wet sprint races, the AI is coming into the pits after 5 or so laps seemingly to change tyres, then go back out and complete the remaining 10 or so laps. Are they changing from inters to wets, or is there a way to make them stay out?

I’ve got fuel and tyre wear set to normal, turning fuel use off will I guess fix the first problem, but I’m guessing turning tyre wear off doesn’t fix the second issue?

Thank you in advance, appreciate the help this community provides .

Are you using Crew Chief GTR2 Enhancements Plugin? For CCGEP there is a tool that can help you setting up your events.

 

[The Iron Wolf]

So, couple of hints. If you run CCGEP, this tool https://thecrewchief.org/downloads/gtr2/CCGEPMonitor.zip can help in setting up AI events. Run the game in window and simulate the event to see what AI is doing.

You can improve fuel situation by adjusting FuelUsage in track AIW: https://www.isrtv.com/forums/topic/7293-stopping-the-ai-pitting-on-last-lap-and-aiw-fixes/

Then, simulate the event and see what AI is doing, Monitor is very helpful with that.

FuelUage improves things, but to have rock solid solution I use pit strategies. See this thread: https://trackaholics.forumotion.com...t-of-fuel-and-forcing-the-mandatory-pit-stop/ it is time consuming, but I can create nearly perfect events.

Lastly, for wet depending on how intense rain AI may enter endless pitting cycle. You can see that in Monitor, one of the solutions is to make rain more intense and test.

HTH

 

[racer69]

Are you using Crew Chief GTR2 Enhancements Plugin? For CCGEP there is a tool that can help you setting up your events.

I’ve got the anniversary patch but not the crew chief plug in, I will try that out

 

[racer69]

So, couple of hints. If you run CCGEP, this tool https://thecrewchief.org/downloads/gtr2/CCGEPMonitor.zip can help in setting up AI events. Run the game in window and simulate the event to see what AI is doing.

You can improve fuel situation by adjusting FuelUsage in track AIW: https://www.isrtv.com/forums/topic/7293-stopping-the-ai-pitting-on-last-lap-and-aiw-fixes/

Then, simulate the event and see what AI is doing, Monitor is very helpful with that.

FuelUage improves things, but to have rock solid solution I use pit strategies. See this thread: https://trackaholics.forumotion.com...t-of-fuel-and-forcing-the-mandatory-pit-stop/ it is time consuming, but I can create nearly perfect events.

Lastly, for wet depending on how intense rain AI may enter endless pitting cycle. You can see that in Monitor, one of the solutions is to make rain more intense and test.

HTH

Thank you for those links. Will go through them all

 

[Caribstu]

I could be wrong but it's been my understanding you can set the AI by editing the GDB file.

For example:
SettingsFolder = JCW-Mini
SettingsCopy = Grip.svm
SettingsCopy = Haydock MINI Coop RACE.svm
SettingsAI = Haydock MINI Coop RACE.svm

The AI will adopt the set up and pit strategy saved as the RACE.svm
If you're running fuel to the bare minimum (lowest value of 15 laps of fuel for a 15 lap race) then some AI may pit for a 'splash and dash' if the fuel level gets too low, depending on the AIW file FuelUsage ratio.

 

[Caribstu]

So, couple of hints. If you run CCGEP, this tool https://thecrewchief.org/downloads/gtr2/CCGEPMonitor.zip can help in setting up AI events. Run the game in window and simulate the event to see what AI is doing.

You can improve fuel situation by adjusting FuelUsage in track AIW: https://www.isrtv.com/forums/topic/7293-stopping-the-ai-pitting-on-last-lap-and-aiw-fixes/

Then, simulate the event and see what AI is doing, Monitor is very helpful with that.

FuelUage improves things, but to have rock solid solution I use pit strategies. See this thread: https://trackaholics.forumotion.com...t-of-fuel-and-forcing-the-mandatory-pit-stop/ it is time consuming, but I can create nearly perfect events.

Lastly, for wet depending on how intense rain AI may enter endless pitting cycle. You can see that in Monitor, one of the solutions is to make rain more intense and test.

HTH

That's interesting. First i've heard of CCGEP

Is it possible in the software to create a variety of strategies for AI. Say... some starting on a hard tyre with no planned stops, and others on a lower fuel soft tyre one stop?

 

[The Iron Wolf]

That's interesting. First i've heard of CCGEP

Is it possible in the software to create a variety of strategies for AI. Say... some starting on a hard tyre with no planned stops, and others on a lower fuel soft tyre one stop?

CCGEP is Crew Chief GTR2 Enhancements Plugin. Monitor I mentioned above receives data from the plugin, and can be used to get some insights into what AI is doing. It is based on my rF2 monitor, and I decided to port it to GTR2 to simplify monitoring of the AI behavior. It only works with my CCGEP plugin.

Monitor does not automate pit strategy setup. Maybe one day that will happen, but not yet. Currently it's just a monitor (helpful to understand what AI does in a simulated event, or after the race), not pit strategy editor/applier etc.

Thanks for mentioning .svm thing, it's amazing how many ways there are to do similar things in those gMotor based games. .svm approach might be faster/easier for some events than explicit pit strategy discussed in my trackaholics thread. However, explicit pit strategy helps dealing with the pit stall clashes.

 

[jgf]

Fuel usage is a combination of the consumption parameter in the engine file and the fuel settings in the track AIW file, but these also affect the player car as well as AI.

AI pitting can seem rather capricious since they are programmed to pit for many reasons that aren't obvious - weather/track changes, engine "health", body damage, etc. Engine health is often overlooked; you cannot control this directly, it is randomly set at the start of a session, usually between about 20% and 100% (you can see this with the XD plugin). The base for this is set in the .eng file -
LifetimeAvg=10800
LifetimeVar=2250
"Avg" is the average lifetime, in seconds, for the engine; "Var" is variance around that so not all those engines will be identical. So if you start a session with 50% health your engine is already down to half its lifetime. If you abuse the engine the health decays even more rapidly. I believe the AI will pit when their engine health drops to a certain, unknown, level.

For AI to use the player setups you must have -
Vehicle Specific AI Setups="1"
in your .plr file, then copy your setup to the team folder (where the .hdc, .eng files, etc. are located) and rename according to the "SettingsAI =" in the AIW file. Obviously you can edit any setup for whatever you want the AI to have, including tires; but tire selection will only hold for the start of the session, the AI will pit for changes as they see fit.

 

[monzaq3]

And what does exactly the FuelUse line in .AIW file do? The larger the number, the more fuel consupmtion is, right?

In this thread (https://www.isrtv.com/forums/topic/7293-stopping-the-ai-pitting-on-last-lap-and-aiw-fixes/) it's assumed that for a realistic fuel consumption FuelUse should be 16x laplength. Is it anywhere near to how it really works?

 

[Nebehr]

Not necessarily 16x. For me it worked with 11-12x. It might depend on the car you are using. Also, lap length in AIW itself may be calculated incorrectly.

It is in fact not necessary to simulate the event to see if AI will have enough fuel, because apparently it is calculated similarly for player and AI. Therefore I usually fuel the car for "1 lap" and then go to open practice and see if it lasts for one lap. If it does, fuel consumption in AIW is set correctly (or perhaps even excessively).

 

[jgf]

The AIW file fuel usage affects any car at that track and is, from what I've read, an oddball computation. It reflects fuel consumption per rpm; so driving wheel diameter, gearing, and engine type all factor in to a value of how much fuel is burned per revolution, this is then applied to how many revolutions the engine turns during a lap. What default values are used for this I've no idea. Mainly adjust it so your "thirstiest" cars will pit at reasonable times; assuming the fuel consumption parameter in their .eng file is reasonably correct.

 

[Durge Driven]

Sorry I don't understand problem if you want to run sprint races with no pits you just turn off fuel usage ?

 

[monzaq3]

I have a similar issue but with long races, not with sprints: some AI cars tend to pit during the last 2 laps of a race.

The situation is: the race distance is, say, 50 laps, and I adjusted the fuel consumption of each AI car so that the "thirstiest" ones would pit not earlier than on lap 29 or 30. This means that the full fuel tank of each AI car allows them to run at least 60% of a race distance — thus, they should be able to easily make the remaining 40% to the end without additional stops. But some cars can't.

I watched the replays of the races where the issue persists, and there are definitely no aerodynamic problems with the pitting cars. I can assume that tyres may be the reason: probably AI cars are able to run 60% of the race on a harder compound (medium or hard), and during the first stop they switch to softs that aren't endurant enough to run the remaning laps. But it's just a hypothesis. Anyway, any solutions and suggestions are totally welcome.

 

[jgf]

If it's always the same AI then it is probably fuel consumption or tire wear, either can also be caused by a very aggressive AI driver. Ride with those drivers for a few laps and see if they are locking the brakes or getting sideways too often.

Otherwise, aero damage is not always visible, so that could still be an issue; an off track excursion or a bad spin may cause an AI to decide he needs new tires; as could a temperature or weather change. Unfortunately we have no way of knowing why a particular AI pits at a particular time unless we witness something that accounts for it. There may even be a random factor in the game that will have a car pit on a certain lap.

 

[monzaq3]

If it's always the same AI then it is probably fuel consumption or tire wear, either can also be caused by a very aggressive AI driver. Ride with those drivers for a few laps and see if they are locking the brakes or getting sideways too often.

Otherwise, aero damage is not always visible, so that could still be an issue; an off track excursion or a bad spin may cause an AI to decide he needs new tires; as could a temperature or weather change. Unfortunately we have no way of knowing why a particular AI pits at a particular time unless we witness something that accounts for it. There may even be a random factor in the game that will have a car pit on a certain lap.

Thank you! Regarding the tyre wear: there is AIWear line in each car's .tyr file that adjusts the tyre wear of AI cars, am I right?

And no, it's not necessarily the same AI, but there are several AI cars that struggle with this issue from time to time.

 

[jgf]

Yes, that tyr adjustment controls wear, but will affect all AI cars using that tyr file. If you want to adjust for one type of car, copy that tyr file to the car's root folder (where hdc, eng, etc. files are located) and rename it, make the edits, then open the hdc file and point it to your new tyr file. (Tyr files will be read no matter where they are so renaming is necessary, though the copy could be left in the Teams folder with the other tyr files; I put it in the car's folder simply so I know which cars are using custom tyr files.)

If no driver is consistently plagued you are probably experiencing the game's random factor, designed to provide some realistic variation in performance (so a strong driver doesn't always win and a backmarker may occasionally finish in the top ten).

Also, make certain you have no multiple talent files for any drivers; the file names do not matter, it is the name on the first line in the file that the game reads. Not sure what happens in this instance, various people have stated the game uses the first one it finds, or the last one, or ignores both and falls back on default values; either way it's rarely what you want. Tom's Talent Scout helps immensely, here it shows I have two files for Adam Jones, with different abilities-

(Note that Talent Scout is from 2008, you may need to run it in XP or Vista compatibility mode, and if you have a lot of talent files it may appear to be not responding while it scans.)

 

[monzaq3]

Yes, that tyr adjustment controls wear, but will affect all AI cars using that tyr file. If you want to adjust for one type of car, copy that tyr file to the car's root folder (where hdc, eng, etc. files are located) and rename it, make the edits, then open the hdc file and point it to your new tyr file. (Tyr files will be read no matter where they are so renaming is necessary, though the copy could be left in the Teams folder with the other tyr files; I put it in the car's folder simply so I know which cars are using custom tyr files.)

If no driver is consistently plagued you are probably experiencing the game's random factor, designed to provide some realistic variation in performance (so a strong driver doesn't always win and a backmarker may occasionally finish in the top ten).

Also, make certain you have no multiple talent files for any drivers; the file names do not matter, it is the name on the first line in the file that the game reads. Not sure what happens in this instance, various people have stated the game uses the first one it finds, or the last one, or ignores both and falls back on default values; either way it's rarely what you want. Tom's Talent Scout helps immensely, here it shows I have two files for Adam Jones, with different abilities-

View attachment 647598

(Note that Talent Scout is from 2008, you may need to run it in XP or Vista compatibility mode, and if you have a lot of talent files it may appear to be not responding while it scans.)

Wow, I didn't know about that utility, thanks! And if there are two files for the same driver, how that affects their pit strategy?