The Williams-Toyota F31 – More (and Less) Than Meets the Eye

by David Phillips on September 29th, 2010

On the face of it, designing and building a virtual version of the Williams-Toyota FW31 figured to be the most formidable challenge yet faced by iRacing.com.  After all, Formula One is the technological pinnacle of the motorsports world, and it takes a virtual army of engineers, technicians and mechanics just to start a modern Grand Prix car.

Thanks to the unprecedented access granted iRacing.com by AT&T Williams – not to mention the close working relationships that developed between the iRacing staff in Bedford, Massachusetts and the AT&T Williams team in Grove, Oxfordshire – the virtual FW31 came together remarkably quickly.  Given the benefit of blueprints and mounds of real world data, creating iRacing’s version of the car was, if not the work of a moment, more straightforward than might be imagined.

“People think that it should be really complicated,” says Eric Hudec, vehicle dynamic engineer at iRacing.com.  “And for Williams, starting and developing the car from scratch, I’m sure it was.  But when you’re dealing with it in a package that’s already finished it’s really not that much different from your ordinary race car.  It’s got a lot of extra little systems, but all the basics sort of work the same way for a Formula One car as they do for a Skip Barber car or a Star Mazda.

“They have suspension geometry that is pretty standard; a few of the bells and whistles are different but all in all it’s sort of the same.  The components are more expensive and they do some things differently for packaging and aerodynamic reasons but, overall, it’s not that complicated.”

The devil, however, is in the details.  While building the basic car and developing its basic – albeit awesome – on track performance may have been relatively routine, adding the state-of-the-art touches that truly separate an F1 car from any other race car has been anything but a simple process.

“What’s complicated are all the finicky little details, including in-cockpit driver adjustments which most cars don’t have,” says Hudec.  “Most of our cars have gauges, dials and those sorts of things to monitor the car’s systems.  But with the Williams, you can pretty much change some major performance factors of the car from the cockpit.  That’s been difficult, from my side, figuring ‘OK, you’ve got these knobs and dials on the FW31, how do I make it so someone racing on their simulator can use the buttons on their steering wheels and keys on their keyboards to affect the same performance parameters of their car?’

“A lot of work goes into the background that says ‘When I hit this button it should make something change on the dash and then affect the physics of the car.’  And the FW31 has a whole bunch of those knobs from differential knobs to an engine braking knob to engine power, so on and so forth. Those have all been built into our FW31.”

Actually not all of them have been built into iRacing’s virtual version of the car.  That’s because, in some respects, the iRacing Williams-Toyota is ahead of its real world counterpart.  Take fuel mixture, for example.  Owing to many factors – ambient temperature, relative humidity, barometric pressure, to name a few – the settings for optimal fuel/air mixture in a real world F1 engine are constantly changing during the course of a race.  Not in iRacing where it’s always mainly sunny and 72 degrees.

“The fuel mixture knob on the ‘real’ car is used if the telemetry shows the fuel mixture’s not precisely right,” Hudec says.  “On our cars the fuel mixture setting is always precisely right.  So we don’t need that knob.”

One aspect of the Williams-Toyota FW31 – be it real or virtual – that is not always precisely right is the aerodynamic setup.  One needn’t be Sam Michael or Patrick Head to understand the aerodynamic downforce that glues a car to the road in the corners is the aerodynamic drag that slows it on the straightaways.  The long–standing prohibition of “moveable” aerodynamic devices has been somewhat modified of late to allow F1 cars one “reset” of their front wing angles per lap.

That cockpit adjustable front wing will be incorporated into iRacing’s version of the car.  When that occurs remains to be seen, however.  And that has less to do with the design of the virtual race car than with the rules ramifications to the iRacing scoring system.

“You are allowed to adjust the front wing angle on the fly in F1, but only once per lap – and back again,” says Hudec.  “Let’s say you go past the pits and your front wing flap is 20 degrees.  You can change it to 30 degrees and then back again, on one lap.  The next lap you can change it to 15 degrees, and then back again, but you can only change one step per lap.

“So that’s kind of interesting, but I’m not sure that’s going to be implemented right away on our car.  There is some underlying code that needs to be changed in order for that to happen. It’s complicated.  The iRacing software needs to know when you complete the lap and record what your previous wing angle was and if you changed it already or not, and implementing that is going to take a little time.”

Indeed, it may well be that iRacing’s virtual Formula One car will imitate the life of a real Formula One car in that its development is ongoing.  And if the Williams-Toyota FW31 that debuts at the start of 2010 Season Four is a bell or a whistle short of the real thing?  Not to worry.

“We will do our very best to get as much out there on the car the first go ‘round,” says Hudec, “but there will be additional features we add as we go forward.

But I’m confident that what we produce, right off the bat, is going to be a realistic – and fun – experience for our members.

“It’s in testing mode right now and it’s mind-blowing.  The performance is unbelievable.  I’ve really enjoyed the project so far, making small changes and getting feedback from the testers, including people at Williams, saying ‘That’s cool’ or ‘It was better before . . .’ I can’t wait for the members to try it out.”