Reasoning your way through the FSAE design process

[Gruntguru]

Originally posted by exFSAE:
Certainly agree that a decent driver will make heaps more difference in lap time than any sort of flexure joint or "optimized kinematics" BS.

This would be an interesting study... say you have a number (10? 20? 100?) of pre-packaged vehicle setups. Some differences in tires.. kinematics.. differential.. whatever. Run them all through a lap time sim, with 3 different driver models for each - a great driver with a nice full round G/G plot, a medicore driver with maybe a rhombus or diamond shaped G/G plot, and a crap driver with the ol' "+" shaped G/G plot.

Of the setups or design philosophies you could play with... would they rank order the same among all three drivers?

Probably not. Even among elite drivers, there can be large differences in setup preference (and pace).

[Bemo]

The old driver discussion...

In my opinion it's just one more aspect of the challenge in FSAE. If you want to be competitive at comp you will definitely need a good driver. So at some point during the year you have to decide who that should be. And the decision should be based on good reasons. The chosen drivers have to bring the necessary talent of course, but they also must be available for testing.
If you finish your car early your drivers can practice a lot before comp. So finishing it early must have a high priority. It helps you to develop a good setup, make the car reliable, perhabs even change some designs. And it helps you to have well trained drivers at comp.
A good example took place at FSG in 08. Before the Autocross there was a special event. Bernd Schneider and Mike Rockenfeller (both DTM drivers) were doing a couple of laps on the Autocross course with our 07 car and the 07 car from TU Munich. Although they are professional drivers with a lot of experience, they weren't able to come near the times, the winning teams did later in the Autocross. Even they would have needed a certain practice time to get used to the cars.
Driveability is definitely underrated by a lot of teams. No matter how good your drivers are you will be faster with a car which behaves predictable and which isn't too exhausting to drive.

[DMuusers]

Originally posted by Bemo:
The old driver discussion...

In my opinion it's just one more aspect of the challenge in FSAE. If you want to be competitive at comp you will definitely need a good driver. So at some point during the year you have to decide who that should be. And the decision should be based on good reasons. The chosen drivers have to bring the necessary talent of course, but they also must be available for testing.
If you finish your car early your drivers can practice a lot before comp. So finishing it early must have a high priority. It helps you to develop a good setup, make the car reliable, perhabs even change some designs. And it helps you to have well trained drivers at comp.
A good example took place at FSG in 08. Before the Autocross there was a special event. Bernd Schneider and Mike Rockenfeller (both DTM drivers) were doing a couple of laps on the Autocross course with our 07 car and the 07 car from TU Munich. Although they are professional drivers with a lot of experience, they weren't able to come near the times, the winning teams did later in the Autocross. Even they would have needed a certain practice time to get used to the cars.
Driveability is definitely underrated by a lot of teams. No matter how good your drivers are you will be faster with a car which behaves predictable and which isn't too exhausting to drive.

Quoted for truth. Driveability is one of our highest priority. You don't win competitions if only one person can drive the car well and everybody else can't. Yes you need talented drivers and yes experience in racing helps a lot, but nothing else compares to FSAE. The tracks are much different to anything else, even between competitions. An easy to drive car isn't only less exhausting for you drivers, but is also easy to be driven fast by everyone. Your drivers can act on instinct even if they don't know the track (and maybe the car) very well.

And a +1 to this thread aswell. Everybody should listen carefully to what Bemo and Geoff says. Even the best teams can learn from this thread.

[Charlie]

Great stuff Geoff and others.

On the driver front I want to clarify one thing, especially for newer teams. Many teams think the driver element is out of their control, but it isn't. A car can be built that is much more drivable than another, and testing improves driver's abilities dramatically.

Just wanted to point that out, as it is in Kirk's response if you read deep enough but I'm afraid many won't.

I don't think I see drivers themselves as important as Kirk or exFSAE do. I certainly don't see them as 'the single most integrated factor in doing well at comp.' Our team worked on a car that was easy to drive for most people and the result was we usually had plenty of capable drivers. For that reason I don't necessarily agree that a top 10 driver could bring a 20th place car to the top 10. Many cars are fundamentally flawed and won't give good driver feedback and a good driver would be just as unable to cope.

[RobbyObby]

Can one of the Mods please sticky this thread? This is some of the best reading by far on this forum! Kudos to Big Bird.

With regard to drivers, we are currently having heated discussions about exactly what Gruntguru pointed out. All of our driver training this year has been in last year's car, and some think that we should decide our drivers once the new car is built because the fast drivers are going to be fast no matter what car you put them in. However, others think that we should let everyone get their fair "tryout" in the new car, since it might suit some drivers better than others, especially compared to last year's car as two major car goals this year are driver ergonomics and driveabililty.
Have any of you guys had an experience where one of your faster drivers from the previous year just could not cope with the new car. Or vice versa, one of your "okay" drivers got in your new car and blew everyone away?

[flavorPacket]

Originally posted by RobbyObby:
Have any of you guys had an experience where one of your faster drivers from the previous year just could not cope with the new car. Or vice versa, one of your "okay" drivers got in your new car and blew everyone away?

Nope. The more FSAE experience they have, the better they are. Maybe if you made a really big change in your car (4 banger to single or 13s to 10s), this might matter more. In my experience it was best to put someone in the car who knows how to execute at competition.

[Big Mo]

Originally posted by flavorPacket:
Maybe if you made a really big change in your car ...13s to 10s, this might matter more.

This is why we were wondering about this question. I know what the data and the tables say about the change in handling, but for a driver, how big is the step down to 10s?

EDIT: The other big driving conflict we are facing is the tradeoff between training drivers and getting the car done. The more we drive the old car, the more money and effort goes into it and away from the in-progress mobile.


Also, agree on the sticky proposition. If this is good enough to be emailed out at Swift, its good enough to deserve a sticky.

[JoshH]

RobbyObby and Big Mo,

I don't have specific experience with FSAE but as an experienced racer (FF,DSR) and SJSU ME Alum I figured I could offer some of my experience. I general the fast guys are fast in just about anything, there’s just something about how certain people interface with the vehicle and can sense the limit. But I would urge you to expand your thinking from just fast to fast and smart. The best drivers are great at balancing risk and reward, but can also wring the car out when need be. These people should stand out.

Josh

[bob.paasch]

Originally posted by flavorPacket:
Maybe if you made a really big change in your car (4 banger to single or 13s to 10s), this might matter more.

Between 2007 and 2009 we went from 4 cylinder to single and 13s to 10s. For autocross and endurance, our fastest drivers were still our fastest drivers.

For acceleration, with the drop in power a low mass driver became more of a premium.

[flavorPacket]

Originally posted by bob.paasch:
For acceleration, with the drop in power a low mass driver became more of a premium.

After being beaten consistently by a girl 40 lb lighter than me, I couldn't agree more!