(And apologies all for the response - wasn't meant to be that long! Nor is this an aero thread - mods feel free to move it elsewhere if deemed appropriate.)
 |
|
|
|
|
|
|
|
(And apologies all for the response - wasn't meant to be that long! Nor is this an aero thread - mods feel free to move it elsewhere if deemed appropriate.)
Geoff,Originally Posted by Big Bird
Yes, of course you may offer your criticisms! I love them. How else can we ever make progress?
And, to hopefully keep this progress going, here is some more critical thinking...
Yes, it is certainly true that there is great diversity in Nature, and even Kardashians can be "fit" enough to fit in. But this is due to the great number of "ecological niches" that are available in Nature.The nature of the complex ecosystem that we live in is that there ARE multiple winners...
...
In the game of life we have mammals and marsupials and insects and bacteria and the Kardashians and fungus...
...
In summary ... multiple winners.
In FSAE terms this translates to there being many "First Places" available for individual events, with each of these being thought of as individual little niches. So one type of car design can win Cost, while a fairly similar, though slightly different, car wins Fuel Efficiency, while a very different car would probably be needed to win Acceleration.
So, yes, sure, lots of different designs can all be winners. (And BTW, I agree with you the FE should be about Fuel Economy outright, with no adjustment for speed.)
BUT!!!
My earlier comments were simply noting that a study of Nature (ie. "ecology", or whatever else it might be called) suggests that regardless of how many differently designed cars show up at an FSAE comp, there is always ONLY ONE design that, IN THE LONG RUN, will prove to be slightly better OVERALL than the other designs. Overall victory in FSAE is like a single "ecological niche". There is only one "Overall Winner", and that is the Team that gets the most points out of 1,000. Simple as that.Same in FSAE – there are enough competing requirements that there very well be multiple EQUAL strategies, but some focussing on cost and manufacturability, and others on carbon fibre and track speed.
There are many subtleties here (such as "bad luck"), but the important point I was trying to make is that the current wishy-washy, let's-all-give-each-other-a-hug, feel-good notion that "all solutions are equally valid" is very misleading!
Note, however, that changing the Rules (or even just the track layout) changes the "Overall ecological niche". This then changes the car design that is "Overall the fittest". And, also, just because a particular car proves to be "Overall fittest" at this comp, does NOT mean that it is absolutely the BEST possible design. Some small mutation of one of this comp's losing cars, may well devour all else at the next comp.
~~~o0o~~~
As a hopefully helpful aside, I might ask: What animal on the Serengeti Plains would be the best role model for an FSAE car, or Team?
I would suggest looking at the African Wild Dogs, aka Lycaon Pictus = the Painted Wolf. These carnivores are certainly NOT the largest or most powerful ones out there, nor are they particularly fast. But these rather scrawny looking creatures, similar to the average stray mutt wandering around your town, do have two traits that FSAEers could usefully copy.
Firstly, they, like early H. Sapiens, have excellent TEAMWORK. Physically, they need this to bring down prey that is much larger than themselves. But their "there is no I in team" ethic also extends to feeding their youngest and oldest members first (the fittest members eat last). In FSAE terms this might equate to intensive training of your first-year members to get them up-to-speed as quickly as possible, and perhaps inviting alumni back to the workshop for free-beer-and-pizza nights so you can benefit from their valuable experience.
Secondly, and again like H. Sapiens, they are PERSISTENCE hunters. They might lack outright power, and speed, and things like sharp retractable claws, but they more than make up for that with stamina and persistence. In FSAE terms this might equate to lacking money, or CNC-tools, or wind-tunnels, etc., but nevertheless having a keep-at-it, get-stuff-built, keep-it-simple, start-testing, rebuild-that-broken-whatsit, do-more-testing, never-say-die attitude, ... that in the long run gets you to that big feast at the end of the year!
My guess is that the above two traits are the main reasons why the Wild Dogs are by far the most effective hunters in their ecosystem. Whereas lions and the other major predators only have dinner after about 30% of their hunts, the Wild Dogs score a win about 90% of the time. In FSAE terms they "score in (almost) all events" (where have I seen that quote before?), and they very rarely DNF.
~~~~~o0o~~~~~
SEXUAL SELECTION.
==================
Along with "survival of the fittest", it is well known in ecological circles that an individual can pass their genes on to future generations by simply being SEXY! This requires an easy-to-survive environment, but just the ability to "do it" with the opposite sex early and often enough, is enough for those "sexy genes" to propagate.
Some insect species have very different looking males and females. Sometimes some of the males look remarkably like the females. So, while big, hunky, alpha-male is busy doing his thing (eg. fighting off the other alpha-males), the girly-boy males can sneak in, and then, ahem..., pass on their genetic heritage. A more obvious example is the male peacock who is burdened with excessively large tail feathers, which probably REDUCES his survival-fitness. But, boy, when he spreads them, don't the girls come-a-running! Pure SEX-on-drumsticks!!!
I mention the above because I reckon that most modern motorsport is a lot more about "sexual selection" than it is about selecting the "fittest" possible cars.
A good example is Push/Pull-Rods&Rockers. These originally "evolved" to improve the aero-fitness of some cars (ie. the ones where clean aero-flows were important). But like the peacock's feathers, PPR&Rs are nowadays on countless cars simply because the purchasers, or spectators, or in the case of FSAE, the other students and (some) Design Judges, think that they are SO DAMN SEXY!!!
Take, for example, the widespread use of PPR&Rs on FSAE cars that make no attempt at aero downforce, or even at reduced drag (eg. spring-dampers high up ABOVE nose, so messing up the flow). Or PPR&Rs on the latest mega-buck $upercar, which has "pushrod suspension, just like on real racecars", even though these are completely hidden from any aero-flows.
Worth noting that at this comp, Monash, who did quite well, had a bucket full of last year's PPR&Rs that they showed the DJs as evidence of how they "lightened, simplified, and improved reliability" of their car, with no adverse affects on performance. Yep, direct-acting spring-dampers. NOT SEXY, but the car was fast...
And then there are those five minute, Team-Leader presentations at the beginning of the Design Event, that look remarkably like the elaborate courtship rituals of Bird's of Paradise, and the like...
~~~~~o0o~~~~~
Two more brief comments (lest this post again gets too long...)
1. I agree with what GTS (Annonymous Aero Judge) has said above. My summarised interpretation of GTS's posts is (please correct if wrong):
"You can get at least as much of an aero-performance gain as Monash gets from their wind-tunnel, or other teams might get from their Super-Computerised-CFD, by simply using A LARGE DOSE OF AERO-UNDERSTANDING to tell you where the air should go, plus a few square metres of plywood/whatever to push the air where you want it to go, plus some wool-tufts/smoke-bombs/Go-Pros/whatever to let you see if the air is actually going where you want it to go."
The most important ingredient above is the "aero-understanding".
~o0o~
2. Any feedback from the Driver-Swap day? (Or are you all still getting over hangovers???)
Z
Last edited by Z; 01-04-2014 at 07:05 PM. Reason: splening!
Yes! Nothing in principle to correct.
(You'll probably get more than what most get from the CFD becuase good CFD is bloody hard, and because no one showed evidence of any solid workflow structure - think about that latter point.)
I am surprised to see nobody addressed one of the big talking points of 2011 and 2012 that is; the average track speed.
After a half shit storm in 2012 that was mitigated by the teams really not being arsed to continue arguing with Rob Chadwick & Co (mainly because he shrugged us off didn't listen and said well its good for entertainment, If you want entertainment take out the cones and put all cars on track, Or go watch race series.)
The avg track speed was said to be 40-48 km/h and it was 65km/h in endurance.
Again this year the rules were released with 40-48km/h average speed and this time much to my amazement the avg track speed was touted at 94 km/h (i have not seen it myself but thats the paddock talk)
This is ridiculous,you have a team who has designed their car for 45km/h done all testing in that region only to come and see it double this is un-fair and not to mention un-safe. Seeing the rmit car in auto-x up the back straight scared the living daylight out of me (pre-oil spill with a shit engine).
How is this allowed to keep happening? - Also just checking the rules again there is two speecs stated, 40-48 or 48-57 with 105km/h speed cap.
Furthermore, again the inconsistent scrutineering was apparent when two identical chassis' with steering wheel height infringements were present, one passed the other failed.
Also, a new rule brought in by scrutineers after 7 years of doing so we are not allowed to use button heads on suspension clevi. This is nowhere in the rules and is now said to be a "critical" bolt. How are 2 M6 bolts "critical" when they have a higher UTS than the glue holding the a-arm? yet even after showing the glue tests and a bolt calc we are still forced to replace all bolts.
There was also talk in 2011 about moving these sort of disputes into design event territory (i.e is you steering wheel is too high but passes roll over) this is bad design as you have not met rules but is still safe. I am not worried about my hands in a roll over if the rear roll hoop has collapsed, I'm already fucked.
Also, the rules state we cannot touch cars when stopped in endurance except to help the driver yet in either 2011 or 2012 (which ever melbourne sent a conrod out to play) all four teams on track were allowed to pull into pits and have jumper batteries to start. Why is this allowed? - The justification was well its an un-scheduled stop....well so is an off track or a stall on the start line why can't we use them then? This again returned to fashion in 2013.
I think there is a great amount of thought and effort being put into the comp and i appreciate everything that is being done but perhaps we could address some of these issues aswell.
For Design event i always thought it would be cool to set up a Q&A between teams whilst judges observe. Where teams judge other teams about their cars, this would allow the judges to see the thought path of the students when assessing new designs. Would love to see some nice arguments too.
Last edited by Moreboost; 01-04-2014 at 06:38 AM.
Not entirely sure, but it sounds like your complaining that they wouldn't pass your illegal chassis? I would say the problem is more that they passed the illegal chassis the first time, not that they rightly failed it the next.
I assume you're referring to this rule? There not much room for interpretation flexibility there.
T3.12.4 The top-most surface of the Front Hoop must be no lower than the top of the steering wheel in any
angular position
It's not just bad design if you make something that doesn't meet the rules IMO. It's failing to meet the first and most important design criteria you have as an engineer.
Would the scrutineers just be following this rule?Also, a new rule brought in by scrutineers after 7 years of doing so we are not allowed to use button heads on suspension clevi. This is nowhere in the rules and is now said to be a "critical" bolt. How are 2 M6 bolts "critical" when they have a higher UTS than the glue holding the a-arm? yet even after showing the glue tests and a bolt calc we are still forced to replace all bolts.
T11.1 Fastener Grade Requirements
T11.1.1 All threaded fasteners utilized in the driver’s cell structure, and the steering, braking, driver’s harness
and suspension systems must meet or exceed, SAE Grade 5, Metric Grade 8.8 and/or AN/MS
specifications.
T11.1.2 The use of button head cap, pan head, flat head or round head screws or bolts in critical locations is
prohibited. These locations include the driver’s cell structure, and driver’s harness attachment.
Note: Hexagonal recessed drive screws or bolts (sometimes called Socket head cap screws or Allen
screws/bolts) are permitted.
Wow. Moreboost, that has come across really angry. I have no problem with criticism, but an angry rant littered with swearwords doesn't really help your cause a great deal. I'll address a few of these points, and I believe that the above poster has done likewise.
Firstly, for the sake of your own credibility I would strongly suggest checking your facts and figures before posting. Basing your first argument on unchecked hearsay is a pretty risky way to introduce yourself. Doing a quick check - Endurance is 22km long, we achieve this in 32 laps, therefore each lap is roughly 700 metres long. 94kmh is roughly 26 m/s, therefore to complete 700 metres at 26m/s, the average lap time would have been 26 seconds. Was it? I'm afraid it was nowhere near that.
As for naming and shaming Rob Chadwick, when you won't even put your own name to your writings, well I put that down as poor form. Rob has a tough job, one which exposes him to a lot of criticism, and he has to make firm decisions and stick to them. He does so with good humour, and he does so voluntarily. When he lays out a track each year, he can be guaranteed that someone will complain about it, whether it be fast, slow or otherwise. And at Werribee he has very little creative licence to do so, given the base track he has to work with. We have had recent criticism that the tracks were too slow, so he opened it up a little. Now it was too fast...
In terms of his approach, would you rather he changed his mind every time a team came up and complained to him? Should we set up the Endurance track by negotiation - and change it upon whim during the weekend? I think you would have a lot more to complain about if we stopped Endurance half way through to change the track just because another team didn't like it.
As for your arguments about batteries, you gave detail of the Melbourne incident in a previous year, but you have given no detail about what you are complaining about this year. So what exactly happened this year to raise your ire? As for the previous incident, well if a car has to stop at an officials directive, through no fault of their own, then they simply should not be penalized the energy required to restart the car. If the car stops from its own error, whether that be an offtrack or otherwise, then it should start under its own power. Simple.
I thank you for the constructive feedback at the end of your post, and in fact your final point is somewhere we want to take the Saturday night design feedback session. I will wear the fact that we did not get around to fully implementing it in 2013, but it is on the cards for coming years.
Kind regards,
Geoff
Geoff Pearson
RMIT FSAE 02-04
Monash FSAE 05
RMIT FSAE 06-07
Design it. Build it. Break it.
That is an interesting point (although 94km/h seem highly unlikely to me). Anyone has average speed data from other competitions? I guess I can figure them out by myself by looking at total times and total distance though...
That actually sounds like a nice idea to me!
EDIT: Geoff, you posted some seconds before I did, great to hear that!
Last edited by mech5496; 01-04-2014 at 06:37 PM.
---
Harry Bikas
UoP Racing Team
UoP Racing website
UoP Racing on Facebook
UoP Racing on Twitter
UoP Racing on Youtube
Hi Geoff,
There is one swear word and it is not aimed at anyone. Shit doesn't even count these days.
94km/h is probably (most likely...ok it is?) an exaggeration, point being it was much faster than expected again.
I am not trying to come across as an angry brat or to shame Rob i am just saying what i experienced throughout my time in the competition. The attitude given to us throughout that event and it was to more then just two teams that queried the track speed and neither of us were taken seriously, lightly or at all. We asked for one thing for future years and that was to update it in the rules.
I am not complaining about the speed, i am complaining that after 2011s tantrum nobody bothered to let the teams know the avg speed would go up again.
In terms of the approach (to track making) i suggest sticking to the guidelines posted in the rules. Then even if someone does try to argue you can look at the rules and close the dispute.
The thing that caught my ire, more then 2 people in the endurance pit area (touching the car, i pay enough attention to see what they were doing). This can be put down to marshals not catching on but they were around for awhile around the cars and marshals did not seem to worry.
So this may be an interpretation of the rules problem i have? (i seem to get it a lot)
D8.11.1 The vehicle must be capable of starting / restarting without external assistance at all times once the
vehicle has begun the heat.
Also, Aukland 2011 stalled because it had to emergency brake behind a stalled vehicle on track they are not allowed to use a jumper the car could not start and DNF'd endurance. The only fault, they were at the wrong place at the wrong time like the cars in Melb's endurance.
I don't mean this in a smart-arse manner.
Luxs yes, terrible design, it shouldn't have been allowed in either cars. FYI neither are/were my car. This was just an observation, a-long with a short list of in-consistencies over the years.
You can get grade 10 or 12.9 button heads. The critical locations is what i was referring too (hence the glue tests). More disappointing was that the students, who had put in the thought/effort to justify their choice of bolt were not heard when pleading their case.
It was all meant to be constructive, these are just my experiences, I am sorry if i grazed anyone's ego.
Edit: I didn't/don't mean to try and shame anyone i have the utmost respect for the organisers and officials, I'm still here like everyone else because i think this competition is one of, if not the best thing (except all the females hurling themselves at me) about doing an engineering degree and i want to see it thrive and continue to develop better students.
Last edited by Moreboost; 01-05-2014 at 04:27 AM.
I'm of the understanding that most teams loved the track layout, Monash and UWA I know expressed concerns with a particular section of track on the Thursday and it was sorted out nice and early. The difficult part in designing a track layout is predicting the performance of the cars to get the ideal average speed. This years track was legal (except maybe for width, but that is more of a venue restriction than something done on purpose.)
As for students trying to justfy their choice in bolt, ie to use a pan/button head. Did they read the rules? Every design must be bound by the rules, just because it may force your design to be less than perfect it is still the rule.
Aus comp seems less strict than international competitions (never been international, maybe one day) but I don't mind, Aus comp is fun! Isn't that what makes this whole learning thing more enjoyable?
tl;dr
Design the car within the rules.
ex-UWA Motorsport
General team member 2013-15, Vehicle Dynamics Team Lead 2012
Project Manager 2011, Powertrain minion 2009/10
Just checked the data for our car (UQ). Average speed was 57km/h, max speed was 113km/h. It's faster than the 48km/h, but hardly close to 94km/h. Personally I loved the track and didn't think it was too fast at all. It also presented a new challenge for us because we'd never really needed to use the brakes that much and all of a sudden we were standing on them into a chicane at 110km/h and cooked them, causing us to hit the over travel switch (shout out to Big Bird for his Roxanne cover during enduro 2). The previous slow tracks never tested the cars in this aspect nearly as much and I'm glad the car was tested for more attributes than just direction change ability.
Posting Permissions
Reply With Quote
