Survey about new aero rules

[Bemo]

I definitely agree that the rules are too vague and things have to be properly defined. There are enough unclear rules already.

Stuff like you suggest with having the cars driving through a gate or whatever if you want to limit things like height or width of the cars is something I can fully agree with. It's simple and there is nothing to discuss about. It fits or it doesn't - end of story. But in my opinion there is not a real necessity to limit the size of the cars in any way. The track layout gives the constrains (if you think about it). If you show up with a car which is too wide and/or long you will have a hard time on the course and that's it. As you said, if there is a max. width given it is very simple for the students to choose their track width as it is already given.

In general I'm also not a fan of the periodic change of the rules sets. In my opinion it makes the series a bit artificial (it feels like the stupid stuff in motorsports is done nowadays for "better show"). If they want to prohibit designs like this year's Ann Arbor car you could just modify the rule about what is considered to be "open-wheeled" (just increase the space which has to be kept free around the tires.

It's also a bit of a random choice to do this periodic change for the aero rules. You could also make a rule which sais that two years you have to use a 4cyl enginge than two years a V2 and then a single to force them to change the engine concept...

[Z]

The track layout gives the constrains ... If you show up with a car which is too wide and/or long you will have a hard time on the course and that's it.

Bemo,

Yes, this has been my point all along.

In Nature, it is the environment that shapes the species. Similarly, in FSAE the Rules can be very open with very few constraints (ie. only genuine "safety" Rules), yet the organisers can still "shape" the car by adjusting the tracks.

So:
* Track with lots of tight-and-twisty slaloms and hairpins = Car that is short, narrow, has lowest-possible-yaw-inertia, and probably also lightweight, non-aero, and low-powered because of low overall speeds.

* Track with mostly mid-to-high-speed sweeping corners = Car with mega-aero, and can be much longer and wider, with higher yaw-inertia, and probably needing higher power engine.

* Track with lots of bumps 3-10 cm high, with wavelength 1-10 metres = Car that MUST have good supple suspension, rather than having a suspension that LOOKS super sophisticated, but doesn't actually work because its springs are rock-hard!

For this approach to work the organisers would have to announce the track layout a year before comp. Or, perhaps, they could just say "Next year we will have a bit more "tight-and-twisty", and a lot more bumps...".

On the other hand, I think it would be particularly interesting if the different major comps around the world each had very different tracks in any given year. That way the "big teams" that attend many comps would have to build an "all-purpose" car so they can score reasonably in all comps, whereas the smaller "local" teams could build a "specialised" car that best suits their comp. Superstar team vs home-field advantage... Who wins?

Importantly, the Rules never have to change.

Z

[MCoach]

So:
* Track with lots of tight-and-twisty slaloms and hairpins = Car that is short, narrow, has lowest-possible-yaw-inertia, and probably also lightweight, non-aero, and low-powered because of low overall speeds.

* Track with mostly mid-to-high-speed sweeping corners = Car with mega-aero, and can be much longer and wider, with higher yaw-inertia, and probably needing higher power engine.

* Track with lots of bumps 3-10 cm high, with wavelength 1-10 metres = Car that MUST have good supple suspension, rather than having a suspension that LOOKS super sophisticated, but doesn't actually work because its springs are rock-hard!

For this approach to work the organisers would have to announce the track layout a year before comp. Or, perhaps, they could just say "Next year we will have a bit more "tight-and-twisty", and a lot more bumps...".

Z

So you mean to say that you want a Michigan road race -- because that perfectly describes the neglected, pot-holed, roads around these parts. We could do some mid to high speed sweeping corners with some up and down hill sections through the city, move it into the neighborhoods and parking lots for some tight twisty runs (still a many potholes) and then maybe hold accel on the highway (still just as many pot holes).

[BillCobb]

So you mean to say that you want a Michigan road race -- because that perfectly describes the neglected, pot-holed, roads around these parts. We could do some mid to high speed sweeping corners with some up and down hill sections through the city, move it into the neighborhoods and parking lots for some tight twisty runs (still a many potholes) and then maybe hold accel on the highway (still just as many pot holes).

D19, from Howell to Pinckney. Most fun in a 5-Series (E46).

[Kevin Hayward]

I like that there is an effort to gain feedback directly from the teams, but I feel there are a number of reasons that will almost invalidate the results.

Firstly, how are the results going to be treated given that they do not attempt to gain any information about the person entering the data. Some teams may not give a response, some teams will actively push members to respond in massive numbers. Unless careful data treatment is applied it will not show any true measure of whether these rules are generally accepted or rejected, even if there is almost universal agreement.

Secondly the questions are probably the wrong ones to ask. A set of rule change directions are presented, with little ability to discuss other options. Furthermore no requirement is made for survey responders to state why they agree for the changes. They only get to make comment if they disagree. This means limited scrutiny for the reasons on one side of the discussion.

My third point is that true feedback from the teams is discouraged by surveys. How about feedback is requested in the form of short reports dealing with the fundamental statements that can be made public and subject to peer review. Almost like a discussion forum ...

...

On the issue of whether the rules are well founded I believe that the reasons for introducing the rules are flawed, and do not appear up for discussion:

Reason 1:
It is often commented by judges, officials and others that have been involved in the various competitions for many years “wouldn’t it be great to change the rules to offer the students a new challenge”.

Flaw:
I have also heard many calls for rules stability. Some say one thing, some say another. The true mark of whether the students have an adequate challenge is if the teams and cars are uniform in design. I think we see the complete opposite of this in the competition. If anything the latest rule change to aero increased, rather than decreased variation. Addittionally there are new challeneges posed in the areas of hybrid and electric competitions. Frankly if a team feels that it is not challenged in FSAE it is wrong.

Reason 2:
A few of the better funded teams have done well with large wings that attempt to fully exploit the aero regulations, but it has been noted that many teams have followed down this path because other teams have been successful rather than because they understand how the benefits will be achieved.

Flaw:
The differences in aero packages is quite apparent, there does not appear to be a lot of whole-sale copying going on. While it is undoubtedly true that some teams lack understanding of why, that particular concern can be expressed in all areas of the car. Why does that team run 10" LCO's, why do they run a 450 single cylinder, why are they running double a-arms, Ohlins dampers, Drexler diff etc. I fail to see how a change to the rules will increase understanding within a team. I would also argue that wings are not necessarily linked to funding of a team. Unlike more expensive equipment such as Motec ECUs, Ohlins dampers, Drexler diffs, multiple sets of super soft tyres wings can be produced quite adequately with fibreglass at $10 a linear metre and wire cut styrofoam. Instead aero packages are much more closely linked to team size, and design capability. Surely we want to encourage areas of the car that influence teams to get more people involved, rather than buying off-the-shelf.

Reason 3:
It is likely that the aero regulations will need to change in 2015 as there are concerns that the wings are too large, several wings have detached from cars causing concern about the safety of marshals and some of the cars have become unstable such that in several cases they have almost rolled over.

Flaw:
No decent argument has been made that makes the point clear that aero cars are inherently more unsafe than non-aero cars. Such arguments can be made in the form of calculations / simulations or as an analysis of statistics of failure. I have seen 1 FSAE car rollover, it was a non-aero car, that went over due to absurd caster jacking and poor corner-weighting. I have seen numerous FSAE cars, both winged and non-winged cars lift inside wheels. I have seen more non-aero components detach than wings falling off. Although I would not want to trust my informal observations. I would rather look at hard data, and vehicle dynamics modelling. Frankly a good collection of inceident reports would be invaluable for the future of this competition. For example if you saw that fire occured much more often than wing failure you might mandate better fire prevention rules, or if suspension failure occured regularly you might start mandating minimum structural standards.


From a basis of argument if your reasoning is potentially flawed then it follows that your response is unlikely to be adequate. My personal take is that there are some good reasons to limit aero performance on the basis of limiting vehicle performance from a safety perspective, however these reasons have not been presented. Furthermore as Z mentions there are plenty of ways within the current rules of limiting performance through track design.

What I believe the initial feedback should have been about was to establish a reasoning framework that the aero regulations can be formed around. A discussion on the agreement on the fundamental reasons would be more productive than discussing options based on potentially flawed goals.

Kev

[Dunk Mckay]

As you say Kev, most justification for limiting wing size for safety concerns could be applied to many systems on the car (and in most cases are not). The only legitimate concern one could put forwards for wings, over any othetr system that could (and often have) fallen off. Is that very large wings are liable to do more damage if the hit someone. A debatable argument as any shattered piece of carbon the width of the car gong fast enough could do a lot of damage to a person, no matter the cross section, and size doesn't necessarily limit mass (heavier=higher momentum=higher injury) as a massive wing made with autoclaved prepreg carbon could weigh the same as a small wing over-engineered and made by wet-lay. But the argument does still stand up as while some large wings might be light enough to be relatively safe, you can't restrict the manufacturing method (not fairly anyway) so the only way to limit mass in worst manufacturing scanario, is to limit size.

So on that basis, from where I'm standing, size limitation for safety does stand up.

I do have as light concern with these suggested rules that they are forecast for 6 years at least. I was really hoping to see a much larger rules overhaul in that time. Pretty much everyone seem to agree that the rulebook is far longer than it needs to be to meet the overall objectives of the competition, or at least no one has argued that it should be made longer. Yet having 3 rule sets will make it longer. Yes so you can ignore the rules that don't apply, but it just more daunting lines of text for the newcomers and uninitiated, and that really does put them off! Why bother setting the rules for the next 2 years so far in advance, why not just change the rules, say that the aero rules will be fixed for two years, then during that 2 year period, see what people like, see what they don't, see where people perhaps need to be challenged more and come up with a new set for the following 2 years. Ideally a new set that intwertwines nicely with all the other new rules that have been brought in, replacing long cumbersome unclear rules with very clear, short but sweet ones.

[Murphy_49]

I have been working with FSAE Aerodynamics for four years and I agree with a lot of what is being said in this thread. I would say:


1. If the judges want to offer the students a new challenge (reason #1), the number of restrictions added should be complimented with equal or more restrictions lifted elsewhere to keep designs changing rather than boxing them in and causing everyone to bring the same car.

2. Copying other teams (reason #2) should not be a reason to change rules as it is accounted for in design. If a team is simply copying another team rather than designing the aerodynamic package themselves it will show when they present based off of what they know. As long as they understand everything behind the design and agree with the results and reasoning they are learning the necessary concepts. (This can’t be done without going through the entire process themselves)

3. The issue of reliability (reason #3) of the aerodynamic packages should not be addressed by limitations of design, but by structural validation. Much like the standardized tests a monocoque must meet.

[acedeuce802]

As mentioned previously, why only mention aero when talking about teams copying others designs? I agree that something needs to be done to try to force a more ground up design approach, but limiting the aero doesn't seem like a totally beneficial way to do this. I like the two methods already stated, one being to change the track. Right after Lincoln, it can be stated that the 2015 track layouts will have an average speed of 25 mph, or 45, or whatever, and different minimum corner radii. This will force teams to consider not only their aero redesign, but it will force overlooking the design of the entire vehicle. The other way would be to change point allocation. What if acceleration accounted for 200 points? Would teams show up with 7.5" rear tires, 6" fronts, and most of the weight on the rear wheels? Would teams go as far as considering switching motors? If fuel efficiency accounted for 250 points, would that alone drive the size of aero packages down? If cost were a 200 point event, would top end aero teams consider ditching the aero package all together?

[mech5496]

Adam, I totally agree, and this would force a bottom-up, back-to-basics approach, but it would also make the differences between the big teams and the smaller ones even bigger, as big teams with lot of resources have proven faster to adapt.

Would teams show up with 7.5" rear tires, 6" fronts, and most of the weight on the rear wheels?

We show up like this anyway.. :P

[Dunk Mckay]

What if there were two point systems on offer, and teams could choose which group they wanted to be put in upon registration? The standard points awarded would stay as they are, but an alternative points system would offer a greater number of points available.

Only a little more thought would be needed for track design. With two sessions, one running the usual track while the other runs similar track with a few modifications, such as making the track wider/narrower, adjusting slalom spacing, bypassing some corners but adding others (many real world race tracks have multiple layouts). The types of track changes that will be made would be announced earlier in the year along with the rules and point systems.

So there would be two types of teams: Those that don't have the capability to make drastic changes every year would be able to perform steady incremental gains with their vehicle design, as they should be now. And those that have much more of a challenge, but think they are up to the task. The rewards need to be greater for the incentive.

The two major problems I see with this are:
A. That a number of teams are going to chase the points when they don't have the capability and will just end up crashing and burning. So perhaps only allow teams to choose the alt points if they have finished endurance at at least 1 of their 2 most recent FSAE event attendances.
B. Balancing the points system could be difficult. Especially if it is changing each year. So what seems like a gamble based on the teams capability could just be a gamble based on how favourable the points system is. In this case I would suggest making the alternative points system results based, i.e. have some sort of equation that bases the points awarded on the best results from the standard rules (yay, another way to add more complications and debate!)