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Nick McNaughton
12-19-2004, 06:25 AM
Folks,

We're putting together a few notes on the 04 Aussie comp to talk about at the follow-up review meeting, before everyone forgets how it all went down.

The whole comp ran extremely well, but we got thrown a few curveballs - namely in the design and cost events, which weren't run how we expected them to be. The strict marking guideline for design judging was a little unexpected, but I actually preferred the way the cost event was run, compared to how the letter of the rules say... it was probably a better test of what we're meant to get out of this competition than getting asked things from a list.

How did everyone else go with the static events? Anyone care to pass comment on how discussion with judges went during the design event? All comments welcome, it'd be nice to know how it ran for everyone else...

Frank
12-19-2004, 08:14 PM
ok, in the "cost discussion"

they didn't ask about the (rehearsed answers) parts listed in the rules

and the design judges were a bit random

some didn't seem to know what they were looking at

our marking sheet suggested we performed poorly on our engine score because

cfd on your radiator shroud not done?
logging oil pressure not done?

4.03 second acceleration run, finished both endures without a hint of restart problems..
makes you wonder....

for the benefit of the chassis judges...

next year we will bring a chassis torsional stiffness rig to the comp

there'll be a cad model supplied before the comp

all teams will need to do is supply 4 small steel plates about 250 * 250 * 6mm
and bring dumb shocks

for that matter, why dosn't the design judging get serious

i'd make it mandatory

tech inspection first

weigh in
cg test (during tilt test)
dyno run (inertial correction run)
chassis torsional stiffness

ALL BEFORE JUDGING BEGAN
(and i'd include that if you can't do the above tests, you don't get judged)

Nick McNaughton
12-20-2004, 03:13 AM
We got some interesting comments in the design marking sheet too, but no cfd on the radiator shroud is a bit tough.

If the design event was run with all those tests, the judges would have a great idea of a very small part of the entire package. It's like assessing a picasso by noting the presence of black and blue paint.

To do things properly (inertia of everything that moves, shock performance, suspension geometry, brake consistency, engine drivability, and so on...) isn't practical, but all of these things will reflect in your dynamic event performance. At the very least, I think there should be a design final judged after the completion of all dynamic events, with your performance in the dynamic events fair game for discussion with judges.

Frank
12-20-2004, 03:49 AM
suspension geometry can be visuallised by those who know what they are looking at

and yes damper performance needs a dyno, but anyone can bring their own damer dyno results

the above are NOT able to be determined visually, and they are very important metrics

for suspension judging I suggest each team has to fill out a set spreadsheet, that describes the static behavior of their car

since >95% of cars run double wishbone, with push/pull rods, and four springs, or a monoshock.. these would suffice

cars with other suspensions could devise their own comparative spreadsheet

http://www.uq.edu.au/fsae/suspension/four_springs.xls
http://www.uq.edu.au/fsae/suspension/front_and_rear_monoshock.xls
http://www.uq.edu.au/fsae/suspension/front_monoshock.xls
http://www.uq.edu.au/fsae/suspension/rear_monoshock.xls

for example our car has 4 springs and a front (drivers adjustable) ARB
ours would look like this
http://www.uq.edu.au/fsae/suspension/uq.xls

regards

(mr pants down) Frank

Jarrod
12-20-2004, 03:14 PM
i agree Frank, if these 4 tests could be conducted on every car, then the cars can be directly compared, at least eliminate some of the 'optimistic' dyno and chassis test results that we see. With only 20-30 cars at the Aus comp, if every team got organised we could have these tests completed on thursday, getting a dyno would be the only tricky part, but i'm sure something could be arranged without a great deal of hassle. Perhaps if Pat is watching he could put in a few ideas? Any other teams with opinions on this? I think at least autocross should be run before completion of design finals.

Frank
12-20-2004, 08:20 PM
'optimistic' , that's one way to describe the situation

Yeah i could see it a bit of a nightmare in the US comp, but the aussie comp would be easy

open the place Thursday morning first thing, and most will have scrutinizing, brake, noise, tilt, and measurements done.

presentation and cost on Friday morning, and design on Friday afternoon (for the stragglers to have a last chance making it through scruit and measurement)

just make sure the test are (relatively) repeatable

and i agree, design finals saturday night

BryanH
12-20-2004, 11:48 PM
I'm sure the guys at Dyno Dynamics would jump at the chance to support fsae. Plenty of Uni's have purchased DD dynos
Hope your test rig is stiff enough for a real carbon tub.

PatClarke
12-21-2004, 02:49 AM
Someone mention my name????
Its difficult for me to comment about Design Judging as I am a senior design judge in the US and the UK. Although I see what Frank is getting at, I doubt it will happen.
I too was somewhat disappointed at some aspects of design judging this year, however, most of the previous years gremlins had been exorcised.
Next year, with improvements learned from this year it will be perfect http://fsae.com/groupee_common/emoticons/icon_wink.gif
I would like to see the preliminary judging select cars for a final, based on all the usual parameters. These would go to a final, where the slate woul;d be wiped clean, and a single group of judges, comprising the leader of each design crew and the specialists like Ron T, Peter G and even Claude R. if we can have him, judge the winners on Saturday night. No team should qualify for the finals in judging if they have not started in at least one dynamic event. In the case of a team getting chosen as a finalist, but unable to start in dynamics, including the Enduro on Sunday, they simply go to 'best of the rest' who didn't make the design finals. This would mean that design results might not be final until lunchtime Sunday.
At the US event, a Dyno sheet is required for all finalists to enable proper powertrain judging. As Half Assed ( http://fsae.com/groupee_common/emoticons/icon_wink.gif) has suggested, it would be great to have the guys from Dyno Dynamics come help us.
Regards to all, I hope Santa is kind and I wish you all a Happy Christmas/Hanukah or whatever else is appropriate at this time of year.
Pat

PS, Tokyo Denki did get their car running, albeit 2 weeks late. They can be seen testing at this address http://www.tdu-card.jp/projects/fsae/assets/kyou/041219_sh.wmv

Pat

Nick McNaughton
12-21-2004, 04:52 AM
Pat,
Our feedback on the design judging will no doubt support changing to that sort of arrangement. Another thing that'd be nice is if the all-star judging team gave a guest lecture before the comp, like in 2003. That worked pretty well...

Frank,
If teams are 'optimistic' about test results, the design judges should be of the experience and calibre to call them on it. Tall stories tend to not stand up to educated scrutiny, so all the event organisers need to do to solve this is provide the educated scrutiny. In any case, all teams should be armed with extensive test results and supporting knowledge for the design event, and each should be just as important as the other in the judge's eyes. Having said that, an on-site dyno and associated glory prize would certainly add something to the competition.

Perhaps the resources that would have been used measuring torsional stiffness and CG etc could be put towards organising another dynamic event ... like a 3 lap sprint event on the autocross track, preceding the single lap event. Track and surface specific setup would be possible, and it'd give the teams a better shot at achieving their best one lap time. Just an idea...

Eddie Martin
12-21-2004, 11:44 PM
I think the biggest problem with that plan, Frank, is the volunteers and officials you would need for an extra day. sae-a struggled to get enough to run the enduro on sunday. I don't see how you would get an extra day in the schedule.

On the design and cost judging more people with experience in fsae and motorsport should be the judges, some don't have as good an understanding of the competition as is needed. This has improved a lot over the last couple of years but it can keep improving. I think a design final is a must though.

Frank i don't know much about the powertrain side of things but not logging oil pressure is pretty silly. Just cause it seems to be working fine doesn't mean there isn't a problem.

Frank
12-22-2004, 05:31 PM
when we get a dash Eddie, next year http://fsae.com/groupee_common/emoticons/icon_wink.gif


Nick, "If teams are 'optimistic' about test results, the design judges should be of the experience and caliber to call them on it."

Can you seriously expect someone to be able to judge chassis torsional stiffness from inspection?

Surely a team like UWA that invests so much, intellectually and fiscally, into the behavior of dampers must be resolute about chassis stiffness?

Nick McNaughton
12-22-2004, 09:04 PM
Beyond a ballpark estimate, probably not. However, the actual number is only half the story - the discussion that goes with it is arguably more important than the number itself for the design event. Chassis judges ranking teams on the number they quote as torsional rigidity without other considerations is as bad as engine judges ranking teams based on peak hp and nothing else. If that's what's happening, the accuracy of the quoted number isn't the biggest problem. Wouldn't suprise me, we were informed in the design event that the chassis and suspension are actually the same thing. To think, we've had it wrong all these years...

As for us, thanks to the technology and materials we use, we can make all sorts of stiffness compromises to help other systems and have it still come out rediculously stiff. This doesn't in any way detract from how important a stiff chassis is to damper performance, as you say...

V2 - Italy
12-23-2004, 03:57 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Frank:
suspension geometry can be visuallised by those who know what they are looking at
cars with other suspensions could devise their own comparative spreadsheet

http://www.uq.edu.au/fsae/suspension/four_springs.xls
http://www.uq.edu.au/fsae/suspension/front_and_rear_monoshock.xls
http://www.uq.edu.au/fsae/suspension/front_monoshock.xls
http://www.uq.edu.au/fsae/suspension/rear_monoshock.xls


(mr pants down) Frank <HR></BLOCKQUOTE>

I can't open your link.
Could you help me.

BryanH
12-23-2004, 05:55 PM
Frank, If you want a dyno shootout at 2005 it would have to be set up and operated very precisely to get repeatable results. I've found that low inertia cars on soft tyres are notoriously difficult to get repeatable chassis dyno graphs off. But after much testing in the last 2 years on zetec f-fords and the occ. f-sae I've found that repeatable runs are possible. Also Dyno Dynamics have done much R&D on repeatibility due to the dyno shootout craze.

The method I use is to hold the car by the clamping the front wheels only and such that the rear tyres can't lift off the back roller at any time during the acc. run. If the tyres do lift off the graph will be +20% higher, as the software is allowing for the inertia of 2 rollers. (on a full size car this has almost no effect)
Hard or cold tyres can wheelspin and this produces a high looped curve (+30%) but is easy to pick. Ideally all cars should be tested on the same brand and compound. Certainly need to be at the same tyre pressure.
A method of quick safe adjustment of the front ramps would need to be done to allow for diff. wheelbases.
The rear straps are fitted loosely only for safety.could be left off. I've found that static loading soft slicks into the rollers causes a dramatic increase in friction/power loss at the top end of the power run (15-20%).
To answer a much earlier Q from John Bucknell the correction factor is calc by the software which asks for all atmo reading hourly and corr. factor I usually see is around .970 to 1.00 (we are close to the sea)
In "shoot out" mode the software is locked and no operator adjustments can be made.

Merry Christmas hoping your mother-in-law is easier than mine Bryan H.

woollymoof
12-25-2004, 09:31 PM
We spoke to one of the Dyno Dynamics guys earlier in the year, when we were sorting out our dyno, about a shoot out at the comp. He said it costs DD about AUD$100k to do Summer Nats and although it would probably cost a lot less to do FSAE-A, it's still unlikely. But having said that, he wasn't the boss. Perhaps a call from SAE-A or petition might go along way.

The guru of guru's
12-27-2004, 02:18 AM
Why is a dyno shootout so important, i understand it could validate everyones charts however some teams are not purely power driven, and opt for a different approach to achieving a quick car....a dyno shootout would have to be classed.....4,2 and 1 cly. Otherwise you would have teams such as rmit and us battling against the gongs turbo 4. Maybe a power to weight ratio contest is in order http://fsae.com/groupee_common/emoticons/icon_wink.gif

Frank
12-27-2004, 04:29 AM
i guess the success of a dyno shootout depends on what gear ratio people have in top gear

The guru of guru's
12-28-2004, 12:09 AM
it all sounds like a bit of a wank....how bout a comp where you time how long it takes for each uni to restart their engine after the first half of the enduro...

Nick McNaughton
12-29-2004, 05:32 AM
Forgive me for trying to drag this back on topic, but does anyone else have any comments on how the static events were run?

ben
12-29-2004, 08:07 AM
I thought the cost judging in Aus was noticably worse than in the US or UK. Thequestions they ask were just too vague and they didn't cover the required elements in as structured a way as the other two comps. I thought presentation in Aus was fair.

As far as design goes, I like the idea in Aus of having a specific suspension guy, powertrain guy, etc. However if you're going to do this, you must have an electrical judge as well. Those of use who did a lot of work on electrics shouldn't have that work passed over because non of the judges present is specifically there to look at it.

Ben

Amos
01-02-2005, 08:08 PM
Have just come accross this thread, thought i would say a few things regarding cost and design, (seems reasonable considering the thread title!!)

I am nowhere near as experienced in design judging as others here (as i have only attended one comp. and this was my final year) but from what i gathered it was in the most part reasonable. Myself and what i like to call "rear end guru" were judged for suspension design, it seemed that a lot of questions were asked - yet not too unreasonable, and that they were also competently answered (usually by Clausen). Other than suspension though, the chassis leader seemed fairly happy with how things went and the Drivetrain leader was a little suprised at some of the left field questions like "wheres the flow calcs for the air filter?" This seems a bit strange to me!

Other than that i think the design judging was fine - but i might be a bit biased considering the results!

On the other hand i would like to pass comment on the cost report. I was generally unhappy with this event. It seems to me that a large amount of experience in the event is the only way to win. We costed our vehicle as close to the exact price as we thought possible (Well Pete did anyway!), and for being honest we got absolutely slaughtered.
From what i gathered (I was not part of the cost judging) the judges had already made a decision on our position before they even walked into the tent. They simply asked whether we could explain why our car cost twice as much as nearly every one else's in the field. This seemed a bit odd considering the professional/expensive look of most of the cars in the field. How could our car cost twice as much as anyone elses? Sure we had a lot of NC machined parts and custom made parts, but we still couldn't see that larger gap in cost.

At this point i would like to make clear that i'm not whinging about how we placed, nor am i whinging at how the judges did their job. I am however dumbfounded by how other teams are able to cost parts so low!

Greg H
01-04-2005, 12:33 AM
Our car was costed low because it was based on the production of 1000 units, some teams overlook this and price it for one-offs. We also lowered our cost because we use cheap materials and simpler design. I made last year's cost report and I can say it is accurate to my knowledge.