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franz887
11-27-2006, 08:31 AM
What do you think?

Is it ok, if a car wins design (or is pretty good in it) and it doesn't run any (or all) of the dynamic events???

Should there be a different way of judging?

Bill Kunst
11-27-2006, 02:13 PM
theory of design vs. execution?

It is a good way of thinking if you are trying to win. Your car must run all the events, and hae a good design. What happens to the team with the amazing car and a blown engine after skid pad? I don't think that we can expect every good car to always win/compete in all events. Look at the world of racing, plenty of teams end up as non-qualifiers or at the back of the pack due to some type of failure or poor execution of a good design.

Should the team who kicks ass in acceleration be discredited because they didn't make design finals? Its like a girl, you want the complete package.

Jersey Tom
12-05-2006, 09:47 AM
You can have a good design and bad luck. I like the way its split up.

The better your design the more you can mitigate bad luck though. I don't recall any cars doing great in design and then horrible in dynamic.. other than mechanical problem DNFs in Enduro. But that's racing.

Biggy72
12-05-2006, 04:56 PM
I don't know about tying the design event and reliability together, but I would like to see something like bonus points awarded to teams that finish all events.

flavorPacket
12-08-2006, 10:57 AM
I don't recall any cars doing great in design and then horrible in dynamic.

3 letters, Canadian, ends in S, I'll give you one guess

terra_dactile
12-09-2006, 11:42 AM
Hello ,
Yes as mentioned by flavor packet, we at ETS have done very well in the design event, and not so hot in dynamics events over the past few years. FSAE 2004 4th Design event, Fstudnet 2004 1st Design, Fstudent 2005 1st design, detroit 2006 2nd Design, California 2006 1st Design. The difficulty with doing well in design lately is that you have to have a very light car, but with a light car you have to know all of your real track time loading inorder to insure that a safety faxctor of 1.5 or 2 is really accurate. Say this what really suck is that over the past few competition , we have never finished the endurance, however it is never because of fatigue or overloaded parts, but issues with preperation, checking nuts, bolts, flat tires, loose center lock nuts, brake pedal adjustements, cheap switches etc... Maybe the reason we have had this trouble is that if you want to win design, it has to be your priority from the beginning to the end of the project, meaning alot of time is spent doing project such as torsion test, crash tests, stiffness test, inertia test etc.. inorder to impress the judge of the accuracy of our calculations, where as testing on the track instead of spending time trying to win design might have made us better drivers and maybe even more competitive on the track. What we must never forget is that the whole point of this competition is to train engineers for the automobile industry, we have learnt alot over the past few years and when it come to getting jobs after competition every one of our team members can chose a job that resembles what they were doing in the team, Some examples of job offers we have gotten are the following: TRD Nascar(Engine project), Bosch, Tilton Racing, Newman Haas Racing,Ilmor engineering Inc,StopTech,ACG (Mclaren F1), Performance Friction Brakes, Continental Teves,Ford, GM, Chrysler and many more...This is in no way me tring to show off, but the point is that obviously winning design does not give as many points as winning the endurance or any dynamic events, I believe the rules should stay the same, giving those who don not design a new car every years more points for finishing the dynamic events would just make this problem worse (sorry Biggy but its true, there are teams that show up with very similar car to the years before, get raped in design event , but kick ass on the track)
If your were to take the best FSAE drivers, I am convinced that if you put them in any of the top 20 Cars, they would be the fastest on the track.
However we are not here to be come proffesional drivers, we are here to learn how to become engineers in the automobile industry and although we at ETS have not performed at competition how we have during testing, when everything falls together and we do well in the dynamic events, we are going to win the overall competition! Hopefully that is during the time I am still on the team. Take all of the static event points in Detroit 2006 or California 2006 and we were number 1 out all the teams competiting. We just have to prove ourselves on the track now!

Just for your information, ETS has a strong dynamic history, Formula Student 2001 2nd overall, 1st overall dynamics events, endurance, autocross etc..FSAE 2001 6th overall with zero points from the acceleration event because of a broken driveshaft, 1996 FSAE 3rd overall, 1st design.

Sincerely,

Jude Berthault
ETS FSAE 2003-Current
Vehicle Dynamics Leader

Biggy72
12-09-2006, 07:46 PM
From what I have seen I believe a well established team should not have any trouble at all having enough time and forethought to prepare their car for a particular competition. If a part is not reliable, redesign it. If you're putting it together the night before comp and you don't know what works and what doesn't I think that's your own fault.

BrunoC
12-09-2006, 11:11 PM
I think Biggy has found the major point to be competitive, preparation. Preparation is very important in every thing. For examples, to obtain a good note at your final exam you prepare yourself at least one week before it. When you do your own carbon fibre tub in house, with the resin infusion process, you spend a lot of time on the mould preparation to have a nice finish. To obtain a good result in dynamic events, you prepare your pilot at least one month before the competition. That is where it gets complicated. Like my colleague Terra_dactille, said we are not pilot, we are soon to be engineer. The purpose of the competition is to apply what you learn during class and after class. Because, if there were no project like formula SAE, then the only application of your knowledge would be during class project. Anyway, if you plan to do good in design, you should at least prepare design board, that will get taken in photo by others teams, and show to the judges that you understand what you did to the car. En terminant, I wish the best of luck to all formula sae team on the 2007 event.

Bruno Côté
Space Age alloy machinist/composite master
École de Technologie Supérieure
Member since 2005

Answerforsomeguy
12-11-2006, 11:42 AM
You hypocrites at ETS.

Complaining about fast cars that are not "redesigned" every year.

This from a team that took 1.5 years to bring a car to FS 2005, and then used what 60-75% of it 10 months later in FSAE East 2006/FSAE West 2006 and then saying you didn't have enough time between July 2005 and May 2006 to tune and test your car and train your drivers.

And having a slow car in skidpad, acceleration, and autocross means you have a slow car even if one day you do happen to finish Endurance once in a while.

A well-designed slow car is just a well-designed piece of scrap. In the real world you design to make a profit/win (unless you are doing research at some University or government organization). A great design that loses is worse then a poor design that does well because at the end of the day you wasted a lot of time and resources to create something that isn't close to being the best.

Focusing too much on design because you are training to be an engineer misses the entire point of the competition. The competition is not about design, its not about driving skill, its not about marketing. Its about learning what is neccessary to design, manufacture, test, and market a small scale engineering project (design, build, competition, sponsorship). Its the whole picture, from the multi-year plan to the smallest detail.

A team that does poor on track has no purpuse being in the top 15 of design in FSAE East.

The worst example is Delft FS 2003. Wins design, fails brake test.

"But the simulations say our car is the best and our design is so Supérieure...."
Who cares how much CFD, FEA, modelling and simulation you do. The only teams that should be in the top 10 for design are the ones that can defend their design both in the presentation AND ON TRACK.

terra_dactile
12-11-2006, 03:32 PM
hello Answerforsomeguy,
First of all it is always nice for those who post to mention there school name/ full name etc.. inorder to show that they are ready to back up what they say on this forum.

In 2004 we were at Formula student and in 2005 we returned to formula student, with elementary level math that makes for one year to make the 2005/2006 car, as a small team 8-12 members we made the decision to have 10 months as you mention to get a car that could compete with the best teams in FSAE EAST. Our plan did not work out as we planned, for your information the reason we did not finsh the endurance is because of my adjustment to the brake pedal,during nuts and bolts the screw used as a stopper for the brake pedal return was tweaked alittle to forward, meaning that there was a little bit of pressure in the brake system before you would even apply the brakes, three laps into the endurance this caused enough heat to lock up all four wheels.This is my fault and it is a shame that this wasted our good advantage of having ten months to test. I went on with lots of greif to win 2nd place in Brake design and First in Calfornia. Is this a design error, or is it just shitty preparation, I obvioiusly feel pretty bad to have caused this shame for my team.

During my previous post in no way was i trying to make excuses for our results, we made the choice to use lots of our time doing tests for design. Your comment of about FEA makes me laugh because in 2004 that was our team exactly, lots of simulations but no physical tests. If you think that telling the design judges we used FEA is why we win design then you have no idea were the level of engineering has gotten, inorder to be considered for the design finals at any SAE competitions, come see me at competition and I will show you the track data/physical test you would like to see, inorder to back up every simulation we have done.

I agree with the fact that a good engineer is not one who make a perfect looking design on paper and simulation and then has the product fail.

The competition rules are perfect the way they are, they make sure that no matter what the comprise we choose there is always something we forgot about and can learn from, our track organization was terrible in Detroit 2006, we got the 7th fastest skid pad time and got it taken away because we were so unprepared that our drivers did our two runs on the same skid pad site, It is clearly stated in th rules that, if there are two sites for the skid pad then the first driver uses one and the second driver has to use the other.

I make no excuses,I Feel that teams like Texas A&M should get more credit in design, because obviously with out a doubt they are the fastest car on track,no matter which of there drivers is behind the wheel, they obviously understand there car on track like no others have been able to within my 3 years experience in formula SAE competitions.

I look forward to meeting you at FSAE EAST or Formula Student this year it should be a great competition.

Sincerely,

Jude Berthault
ETS FSAE 2003-Curent
Vehicle Dynamics Leader

Ben C-M
12-11-2006, 06:45 PM
Before we get too hostile, I'm going to throw in my 2 cents:

I think the comment about simulation versus physical testing brings up an interesting point. I'm sure that every team knows they need physical testing to validate their design, and that any simulation also helps when trying to get design points, but how often does a design judge look at the data (for simplicity, on track data) and say "You guys are slow" and dock you points because of it. From what I've seen, the judges focus on the methods and understanding, but very little on the performance (unless something is out of wack). I personally think they should consider the on track results, at least after the semis.

On the other hand, the purpose of this competition is to score the most points. The point system is set up so that teams require multi-tasking and proper management in order to maximize their point totals. Teams that don't prepare for all the events will not win. That means that a team that does poorly on track, no matter how well they do in design, won't win the competition. Unfortunately, the design event has its own glamour and there are teams that focus all their attention on this one event, which is basically fooling the judges.

The basic purpose of the design event is to judge who shows the best use of engineering to meet the design goals. One of the major design goals is performance, and another is reliability. I don't think that either of these two things are well considered by the judges.

I have a problem with saying that the teams that do well dynamically are the ones that keep their cars the same every year. The cars that do well dynamically are the ones that are fully prepared and don't make mistakes. They're the ones that got their cars finished early instead of putting their car together at the last minute, got the on track testing so that their car was set up perfectly, developed their drivers so that the drivers were comfortable in the car and able to push it to its limit. Setting the brake bias wrong (or whatever) is a silly mistake, but there are teams that don't make those mistakes, mainly because an endurance run is routine for them. Preparation is probably the #1 thing for this competition, and it takes planning almost a year in advance, as well as a lot of discipline, to consistently finish endurance.

Obviously where you decide to spend your time, be it design or on-track or at the bar, is reflected by the points system: the only difference is that design has the most glory.

/Ben

Big Bird
12-14-2006, 05:13 AM
Well firstly I think the barbs at the ETS guys were unnecessary. On the one hand I thought their posts were on topic, helpful and in no way deserving of attack. On the other hand I'd add that these guys' engineering design is first rate, and any wins in design they have had over the years are well deserved. There are files full of photos of the ETS cars here at RMIT, and we have learnt more about design from their cars than any other team in this comp.

Rather than rag them, why not try to strike up a diplomatic conversation? I couldn't think of a more approachable team.

As for the point of this topic, there are already an abundance of points available for performance - the on-track events. We all know the overall purposes of the comp, and the specific purpose of the Design event is to test design knowledge. Sure, some of this can design knowledge can translate to vehicle speed, but that is only a small part of a very large story.

ETS win design because they present a great car and have wider design knowledge than other teams. Full stop. You can try to do better, or you can have academic arguments about why you think it is unfair. Your choice will determine how successful your team will be.

Cheers,