Lap Simulations - Team-BHP

Hatari · 2nd April 2004, 22:55

How does an F1 team approach the challenges of a new circuit? Engineering Director Pat Symonds explains how simulations work… and why they don’t!

As a team, we relish the challenge presented by a new circuit. For drivers, it requires precious practice mileage to be spent looking for the nuances that can shave hundredths off the lap time. For the engineers, though, the challenges begin many months earlier with lap simulations: while it now takes just 40 seconds to simulate a lap on the computer, programming the sophisticated models behind this is a lengthier task…

Logically, the earlier one can start the process of informing the lap simulation, then the better prepared one is; however, this is not always easy. The starting point for a lap-time simulation is to obtain an accurate circuit map from which the trajectory of the car along the racing line can be described mathematically in three dimensions. Once the circuit configuration has been finalized, detailed maps are issued by the FIA, and work can begin. The boundaries of the tarmac are digitized, and fed into the first stage of the simulation programme, which uses mathematical ‘cost’ functions to determine the ideal racing line –this what a skilled driver does intuitively.

Once the racing line has been established, a car model with an ’average’ set-up is introduced. From this, a variety of wing settings and gear ratios can be evaluated to get the basis of the set-up. Once this has been done, refinements are made to weight distribution and suspension settings in order to minimize the virtual laptime. Subsequently, the team can begin to look at energy requirements from the tyres, to help choose the appropriate compound, and at this stage brake energy requirements, and to some extent brake cooling requirements, can be calculated.

However scientific this may sound, though – as indeed it is – a number of ‘imponderables’ can lead to errors in the simulation, that often cannot be corrected until the circuit has been seen and, indeed, until the car has first run on it.

The first of these are the kerbs: where the simulation is only able to assume a driver will use the limits of the tarmac, in reality, they use kerbs wherever they can. If they are relatively smooth and low, they will be used to shortcut what had previously been the ‘ideal’ racing line.

Much more problematic, though, is the variation in grip levels: of the circuits raced on in 2003, grip levels varied by as much as 15%, and if one includes the early sessions at Monaco in the equation, this figure rises to 24%. Naturally, working 5000km from the circuit, we can do nothing but assume an average level of grip and work from there until further information is available. For Bahrain, however, we know the grip level to be similar to that at Malaysia, which is just 2% below the average. However, to put this into perspective, a 3% variation in grip level on an average circuit can bring a change in lap time of around 1 second and just to make things worse, this parameter varies continually, even during the same day… In order to insure against this, the team conducts numerous simulations at different grip levels in order to have a bank of data at their disposal in the event of changes, so that the appropriate car set-up can be decided upon as quickly as possible.

Once that has been completed, and the car is running, we then begin running more simulations for race strategy. In fact, before making our decision on Saturday, over 1,000,000 race scenarios will run through the team’s computers!

FOR THE RECORD..
the lap times were predicted to be in the 1min. 30s
DEAD ON !

GTO · 2nd April 2004, 23:06

Hey,

Great article...I clearly remember Jenson Button being asked how he coped with the unfamiliar tracks in his debut season with Williams-BMW in 2000 - The answer? F1 games!! He acknowledged the fact that they helped him learn his way around the track!

GTO

Dippy · 2nd April 2004, 23:14

I guess no game has the Bharin and Shanghai circuits in them so for now its upto the good old scooter to get a feel round the new tracks

Cheers

Pferdestärke · 3rd April 2004, 00:40

I dont know if this video has been posted here b4, but is a good download, check it out
URL:
http://www.mainax.com/movies/simulator_700kbps.wmv

As we were talking about Simulators I thought i'd be a good Idea to post this one. (Right-Click on the URL and Save Target As.. )

Wraith · 3rd April 2004, 03:13

The qualifying on saturday is sure gonna be lot of fun.with no teams having any experience with the track its gonna be anybodys day tommorow ep with the ups n downs of tyre performace and the sand thing!!
Its gonna be exciting to watch qualifying!!

I have my money on Micheal winning the race!!

Hatari · 3rd April 2004, 20:00

yeah wraith.. betting on MS looks like the safest thing to do !
man.. the ferraris' are blazing !

2nd April 2004, 23:06	#2 (permalink)
GTO Team-BHP Support Join Date: Feb 2004 Location: Bombay Posts: 13,115 View My Garage	Hey, Great article...I clearly remember Jenson Button being asked how he coped with the unfamiliar tracks in his debut season with Williams-BMW in 2000 - The answer? F1 games!! He acknowledged the fact that they helped him learn his way around the track! GTO __________________ GTO Change the way you think, and watch the world change around you. Please don't PM for support. Use the Contact Form instead. Please read the NEW Team-BHP FAQ section for all your queries.

2nd April 2004, 23:14	#3 (permalink)
Dippy Team-BHP Support Join Date: Feb 2004 Location: Mumbai, India Posts: 4,575 View My Garage	I guess no game has the Bharin and Shanghai circuits in them so for now its upto the good old scooter to get a feel round the new tracks Cheers __________________ My name is Adrian Sutil. You can call me ADDY - Force India dippy@team-bhp.com

3rd April 2004, 00:40	#4 (permalink)
Pferdestärke BHPian Join Date: Mar 2004 Location: Bombay Posts: 269	I dont know if this video has been posted here b4, but is a good download, check it out URL: http://www.mainax.com/movies/simulator_700kbps.wmv As we were talking about Simulators I thought i'd be a good Idea to post this one. (Right-Click on the URL and Save Target As.. ) __________________ Reasons aside.. Its just not a Ferrari. Ferrari?? The Italian Trash..? Kill Bill

3rd April 2004, 03:13	#5 (permalink)
Wraith BHPian Join Date: Mar 2004 Location: Mumbai Posts: 75	The qualifying on saturday is sure gonna be lot of fun.with no teams having any experience with the track its gonna be anybodys day tommorow ep with the ups n downs of tyre performace and the sand thing!! Its gonna be exciting to watch qualifying!! I have my money on Micheal winning the race!! __________________ Remember RESPECT is EVERYTHING

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
One Lap of America	madan80	Motor-Sports!!	1	8th May 2008 21:43
The best qualifying lap I have seen..	Hatari	Motor-Sports!!	5	27th January 2005 23:44
Best lap timmings	Team Fiat	Shifting gears	0	16th November 2004 06:26
Best qualifying lap of the season ?	Hatari	Motor-Sports!!	1	21st September 2004 15:38
Nordschlife lap times	ported_head	Shifting gears	4	8th June 2004 02:53

2nd April 2004, 22:55	#1 (permalink)
Hatari BHPian Join Date: Feb 2004 Location: New Delhi Posts: 413	How does an F1 team approach the challenges of a new circuit? Engineering Director Pat Symonds explains how simulations work… and why they don’t! As a team, we relish the challenge presented by a new circuit. For drivers, it requires precious practice mileage to be spent looking for the nuances that can shave hundredths off the lap time. For the engineers, though, the challenges begin many months earlier with lap simulations: while it now takes just 40 seconds to simulate a lap on the computer, programming the sophisticated models behind this is a lengthier task… Logically, the earlier one can start the process of informing the lap simulation, then the better prepared one is; however, this is not always easy. The starting point for a lap-time simulation is to obtain an accurate circuit map from which the trajectory of the car along the racing line can be described mathematically in three dimensions. Once the circuit configuration has been finalized, detailed maps are issued by the FIA, and work can begin. The boundaries of the tarmac are digitized, and fed into the first stage of the simulation programme, which uses mathematical ‘cost’ functions to determine the ideal racing line –this what a skilled driver does intuitively. Once the racing line has been established, a car model with an ’average’ set-up is introduced. From this, a variety of wing settings and gear ratios can be evaluated to get the basis of the set-up. Once this has been done, refinements are made to weight distribution and suspension settings in order to minimize the virtual laptime. Subsequently, the team can begin to look at energy requirements from the tyres, to help choose the appropriate compound, and at this stage brake energy requirements, and to some extent brake cooling requirements, can be calculated. However scientific this may sound, though – as indeed it is – a number of ‘imponderables’ can lead to errors in the simulation, that often cannot be corrected until the circuit has been seen and, indeed, until the car has first run on it. The first of these are the kerbs: where the simulation is only able to assume a driver will use the limits of the tarmac, in reality, they use kerbs wherever they can. If they are relatively smooth and low, they will be used to shortcut what had previously been the ‘ideal’ racing line. Much more problematic, though, is the variation in grip levels: of the circuits raced on in 2003, grip levels varied by as much as 15%, and if one includes the early sessions at Monaco in the equation, this figure rises to 24%. Naturally, working 5000km from the circuit, we can do nothing but assume an average level of grip and work from there until further information is available. For Bahrain, however, we know the grip level to be similar to that at Malaysia, which is just 2% below the average. However, to put this into perspective, a 3% variation in grip level on an average circuit can bring a change in lap time of around 1 second and just to make things worse, this parameter varies continually, even during the same day… In order to insure against this, the team conducts numerous simulations at different grip levels in order to have a bank of data at their disposal in the event of changes, so that the appropriate car set-up can be decided upon as quickly as possible. Once that has been completed, and the car is running, we then begin running more simulations for race strategy. In fact, before making our decision on Saturday, over 1,000,000 race scenarios will run through the team’s computers! FOR THE RECORD.. the lap times were predicted to be in the 1min. 30s DEAD ON !

3rd April 2004, 20:00	#6 (permalink)
Hatari BHPian Join Date: Feb 2004 Location: New Delhi Posts: 413	yeah wraith.. betting on MS looks like the safest thing to do ! man.. the ferraris' are blazing !