I guess my teams 2nd place car at FSAE-M is no good.Quote:
Originally Posted by Claude Rouelle
Though I do wonder what the weight sensitivity to lap tone is. Maybe we could have been 1st...
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I guess my teams 2nd place car at FSAE-M is no good.Quote:
Originally Posted by Claude Rouelle
Though I do wonder what the weight sensitivity to lap tone is. Maybe we could have been 1st...
Julian,Quote:
Originally Posted by JulianH
Ah, that is the only type of pre-event that we do. We have our faculty advisor rigorously scrutinizer our car. I was more referring to the formal pre-events like Formula North, ZF race camp etc, mini-competitions.
Noah
Formula North is a "real" competition; not a mini-event.
ZF Race Camp is just a nice help for all ZF sponsored teams. As written above, I really like this event, it helps to "calm" the team members that never experienced competitions, you have a lot of fun and see how the others are doing it.
Can you tell me why you think that your team would be not able to participate in such an event? Let's say it would be ~4hours drive from your university (which is probably the average time that it takes all ZF Race Camp teams to come to Southern Germany).
Will,Quote:
Originally Posted by Will M
The answer to your question above, as I see it, is in the mini-essay below.
However, I have no idea what "...the goals of the FSAE leadership" are. For the last 30 odd years they have certainly NOT appeared to be interested in improving the teams' reliability, because they have provided very little "external pressure" to fix that problem. In fact, in Oz last year they rewarded the unreliable teams!
~~~~~o0o~~~~~
HOW TO MOTIVATE A DONKEY.
=======================
Traditionally, you use the "carrot and stick" approach. Depending on circumstances, you can use one, or the other, or a bit of both.
For example, if the donkey is starving, then dangling a carrot in front of its nose works great.
But if the donkey has just gorged itself on a basketful of carrots, and you hang a second basketful of carrots in front of it, then, for obvious reasons, the donkey thinks, "Are you kidding..., I'm about to explode!".
And he sits down and moans about how bloated he is.
~~~o0o~~~
CASE STUDY 2.
=============
For the few years around 2006+, RMIT was the top team in the world. Then they fell in a big hole, and have never recovered.
~o0o~
Two years ago RMIT-C came to 2015-Oz-comp with an as-close-to-mini-F1-car as you could imagine. Full-CarbonFibre-monocoque, CF-wishbones-with-push/pull-rods&rockers, longitudinally-mounted (ie. F1-style) turbo-charged 85+ hp Yamaha Genesis/Phazer engine (WITH 3-D-printed-titanium-exhaust-manifold), followed by a bespoke 4-speed-CF-cased-gearbox, followed by a viscous-LSD, ... and many other shiny things.
Suprisingly, given the lightweight-twin engine, their claimed mass was a rather portly 185 kg (though probably more, see below). But with all this bling abounding, who cares about some objective numbers? Certainly not the Design Judges, because they gave them,
Design Event points = 140.. Yep, second-place in DE!
And how did this smoking-hot, mini-F1-car perform on track?
Well, TOTAL Dynamic points = 54.4!
So, all things considered, a complete success!
Huh? Why?
Because, as one RMIT-C Team-member explained just a few days after the competition (see 2015-Oz-comp thread),
"Seriously the aim of all this is to ... get a job [and] Two of our members ... have landed employment off this project..."
Clearly, the "carrot" in FS/FSAE is to "get a job". That is most easily done by producing a lot of generally useless, but very shiny, junk, which impresses the DJs enough to give you very high points in the prestigious DE, which then puts you at the front of the queue for that high-paid job.
~o0o~
So, with the 2015 Team-members well rewarded with carrots, which direction do you think the 2016 Team-members were motivated to take?
Well, they arrived at 2016-comp with an all-but-identical car to the 2015 car. The only obvious change was that it had one less gear. And, somewhat confusingly, despite their spec-sheet claiming a mass reduced to 175 kg, the scrutineers' scales said it had porked-up to ~215 kg (both w/o driver).
So, with the mass comfortably above Dunk's suggested minimum, did this mean they had built a much stronger car, with the aim of increasing reliability and thus completing all Dynamic events?
Nope. Their TOTAL Dynamic points = 45.1. Worse than last year.
But Happy Days, again!
Their Design Event points = 136.9. Just a smidge below last year's.
Surely good enough for a walk-up-start at any top-paying job.
~o0o~
So, ... with the 2016 Team-members given another basketful of motivational "DE carrots" to munch on, in which direction do you think the 2017 Team-members will go?
Will they focus on the boring complete-all-Dynamic-events reliability? Or on the get-a-high-score-in-DE bling, and then off to that dream-job next year?
Z
(PS. Claude, I agree 100++% with you that the teams should do a great deal more testing. But try convincing them of that! I might post another mini-essay soon about some of my futile efforts to convince teams of such. :()
That's not very nice Claude. I was merely proposing a thought experiment.Quote:
Originally Posted by Claude Rouelle
What I do get, is that most teams break down because they made X part 'too thin' , and didn't have time to test it properly because they spent it all trying to save even more weight. You've said as much in your "Test, Test, Test" post.
I am playing devil's advocate a little, because I know a lower weight limit does not solve the root cause of the problem. But to do that means somehow forcing the team to do thing s like full FMEA's, proper timing plans, etc. Which would make the whole competition very unappealing, especially when most engineering students call it: "Formula Stupid, that competition where all the cars break down."
I am currently in the position of said 'poor employer'; often supervising new graduates at work. There a lot of lessons that I want them to have learned. But FSAE students don't go away saying, oh we should try to implement better failure mode avoidance. They talk about fixing that one thing and then making their car "lighter, more powerful, faster, etc, AND more reliable."Quote:
Originally Posted by Pat Clarke
I had a 12 month industrial placement leading up to my final FSAE year. During which time I did a ton of research and spent most of my lunch breaks on here and slowly learned not to focus on mass over reliability, mostly thanks to Big Bird's wise word. We went from a DNF team to finishing all events.
Sometimes to learn something people just need to be told. Then they start asking and understanding why.
Your welcome, this was partly my intent.Quote:
Originally Posted by Z
Competition results made available online already do this.Quote:
Originally Posted by Z
The problem is, I was in a team with really good engineers, but I also with some people that should be banned from ever doing engineering professionally.
So looking at the result of the whole team doesn't help much. If the standard deviation within a team is high, then you have no idea what you're getting.
I don't think DE should be dropped, but changed to: Engineering Event. The work 'design' has far too much association with aesthetics, an not how something actually works, or why.Quote:
Originally Posted by Z
I'd like to see it broken into two parts, the Specification and Validation sides of the system V. Starting at a high level, of how they believe they can perform at comp, all the way to what each individual part specification. Then back up through how they they tested their engineering against all their performance targets, and ultimately how they performed at the competition.
The DE purports to do this already. But there is no true attempt to check any of the validation work, if simulation and testing is not done properly, then the results of these a worthless. There is no way of checking these have been done properly, except.... dynamic events. All you have to do is run the design event at the end of the weekend, AFTER all dynamics event and you have all the validation you need.
You can compare their predictions to what they achieved. First you judge if their targets/predictions were fair, considering their resources, then you compare these to their actual performance, and have a discussion about why their not the same (be it a large or very small difference), and score according to their understanding.
Why not include this as part of the DE submission? We require that teams designs the car themselves and judge them on this, so why not require that they test their car as well?Quote:
Originally Posted by Claude Rouelle
If they are meeting their goals, then those goals are not about satisfying employer requirements.Quote:
Originally Posted by Will M
Learning from mistakes is great, but first you have to know what that mistake was. I fear this is rarely the case. Teams will just correct the one thing that went wrong and come back the next year and something else will break. The mistake was not the design of the car, but the way in which they went about engineering the whole project.
This is great if you're being watched by an expert swimmer. But pretty reckless to do on your own.Quote:
Originally Posted by Claude Rouelle
(Academic staff are rarely expert swimmers).
Now this is an idea I can really get behind, and the sort of thing I was hoping to get out of this discussion.Quote:
Originally Posted by Kevin Hayward
YES. THIS!!Quote:
Originally Posted by Claude Rouelle
This is Failure Mode Avoidance, a standard industry tool I know well, and there are much more rigorous ways of doing it that just standing around the car (although that may come into it). The problem is that most team's don't do this, and unless something changes about the competition and it's rules they will continue not to. We can say it's their responsibility all we want, but at the end of the day, it's our responsibility as educators to make sure their are learning to use the right tools, if they could do that on their own there would be no need for FSAE in the first place!!Quote:
Originally Posted by Claude Rouelle
This is exactly the sort of comment that is such a problem. Someone as respected as yourself saying something so judgmental of teams with 200kg+ cars is going to make those team bias their decision making towards low mass, and sacrifice reliability. They will make that mistake, where they otherwise wouldn't have because "Claude Rouelle said we had to be sub 200kg. So logical engineering decision making be damned, we'll just make sure we hit that target."Quote:
Originally Posted by Claude Rouelle
In the last 10 years the two most successful cars my team ever made weighed 250kg, and 225kg. The first was our best ever finish at competition, and the second saw the biggest jump in reliability and results for a number of years. The long term goal each time was to refine those concepts to reduce weight. But, too much focus on weight due to a design judge comment after the 250kg car landed the team with a 200kg car that wasn't any quicker and broke all the time. Following the 225kg concept (ran for 2 years), the team vision fell apart due to new management; they wanted to earn the praise of people like yourself and mandated a super lightweight car. They were the worst year in our team's history.
(I could make a joke here about the reasons people no longer want to listen to experts, #Brexit, but I won't).
But my team aren't the only example. I've spoken to so many teams who go on about getting a sub 200kg car. It's an obsession that needs to be removed for this competition to progress. Sub-200kg might be the right thing for most teams if done properly, but that needs to be a result of proper engineering decisions.
I tell you what, if my team are ever in a position of doing really quite well, and have a car that weighs 199kg, as unlikely as you may claim that to be, I'll make sure they add 1kg of ballast, just for you, Claude. ;)
Dunk
Lost of verbal diarrhea, tentative of justification, pretty pessimistic views, lack of YES WE CAN / WILL MAKE IT HAPPEN attitude, not very useful.
But you give me chance to elaborate on an important point
You wrote : "What I do get, is that most teams break down because they made X part 'too thin". Nope that is not that is not necessarily because the parts are too thin. The goal is to maximize tire grip AND reduce forces on each suspension and chassis part with smart design. It is all about how you distribute the tire forces and moment on your uprights, suspension, chassis etc... That is why design judges ask students to demonstrate both choice of materiel and shape of chassis and suspension elements tanks to load path calculations. Working on the part thickness will improve stiffness and reduce compliance....which will increase the forces on car parts (F= MA). Vicious circle. Think about the way a force of 450 N can be applied on a 0.3 mm egg without breaking it.
LOW MASS DOESN'T SACRIFICE RELIABILITY: WITH SMART DESIGN LOW MASS DOES IMPROVE RELIABILITY!!!!!
****
"In the last 10 years the two most successful cars my team ever made weighed 250kg, and 225kg" BS. What does it prove? Ask your former team members what they would have done if they would have had the choice to add or remove 10 Kg? How come we have several reliable winning cars circa 150 KG or less? (and do not tell me that is because they have bigger budget; I will ask back: do they win because they have budget or do they have budget because they win?)
******
"Why not include this as part of the DE submission? We require that teams designs the car themselves and judge them on this, so why not require that they test their car as well?" Again Outside-In solution. It is up to the team to do it. Inside-Out. Do organizers and design judges need to hold the hands of 17 - 24 years old?
*******
Claude
Julian
I am not suggesting to optimize everything. Your team design and run very competitive, light and most of the time very reliable cars. Every time I (and other judges) speak with your team members in Design (often in finals) it is a pleasure to see your knowledge and enthusiasm. You may have many assets starting with your excellent university (although we have to wonder why some even more prestigious with bigger budget universities such as MIT or Harvard or Cranfield do not show up - or if they show up perform poorly in FS - I have my opinion - but that is another debate) but I guess that despite you have nearly new team members every year, one of the main reasons your team is often on top is that you have an organized system of transmission of information from one year to another.
Here is my point: Big or small budget that is what many teams seem to be missing: they do not seem to have learnt from mistakes from previous years.
My name is Simon and I have been with the Running Snail Racing Team (UAS Amberg-Weiden) for four years now (I have done the software for the cars).Quote:
Originally Posted by Claude Rouelle
Of course the scrutineers need to be qualified. And yes, many issues met in inspection are avoidable. In the last year we did not have any issues in scrutineering at all, but the reason for that was mainly because those who where responsible did it in their second or third year. Normally, most of the people are in their first year and they make mistakes. Pre-events are helpful in these cases.
I totally agree with you on that inside-out-approach, but there is no reason not to do both. In fact, many of those great teams actually attend pre-events (e.g. AMZ, Delft, Karlsruhe, Stuttgart, ... the ZF Race Camp).Quote:
Originally Posted by Claude Rouelle
When I talked to the teams I got the impression that many break downs also happen because of battery issues (BMS, empty, heat), electronic problems, sensor problems (electric cars) and failed attempts to restart at the driver change, leaking fluids, other engine or clutch troubles (combustion cars).Quote:
Originally Posted by Dunk Mckay
However, when talking to teams that suffered mechanical break downs (too thin parts etc.) most of those teams were way below 100km of testing, many of them did not test at all and did parts of the car assembly. A weight limit would not change very much in my opinion, because those teams would still do their first meters at the competition and fail.
The best solution to improve results and reduce mechanical break downs is IMHO just to force the teams to do more testing. So as you suggested in the first post, a vehicle status video where the team must prove that the car is running properly would be great for every competition. However, I would not give additional points for teams that are able to provide the video, but instead just exclude all teams that fail to provide it (about one month before the competition).
Those teams can be replaced with teams from the waiting list that were able to build a running car. FSG does this already (although until last year, you could apply for an exception). This should be communicated to all of the teams and would built a lot of pressure to get the cars running in time. Also I feel that a team that failed at the registration quiz but was able to built a running car deserves it more to take part at a competition than one that succeeded at the quiz but did not build a running car in time.
It would be interesting to see, how testing corresponds with reliabilty/success. At least for my team, there is a clear dependence:
2013: ~600 Test-Kilometers before the first event, 1 pre-events, 3/3 Endurance finished (6th FSUK, 7th FSG)
2014: <100 Test-Kilometers before the first event, 0 pre-events, 0/3 Endurance finished (17th FSG, 15th FSA)
2015: ~150 Test-Kilometers before the first event, 2 pre-events, 1/3 Endurance finished (24th FSG, 3rd FSH)
2016: ~600 Test-Kilometers before the first event, 3 pre-events, 3/4 Endurance finished (4th FSG, 1st FSH)
Have been enjoying this thread. A bit of history, when I started design judging (c.2000) in Michigan, Design Finals were Sunday morning after Dynamics were over. By then, only about a dozen judges were left to talk with 3-5 FSAE teams and look at their cars. After talking with the teams, we sat in a circle and came to a final ranking by simple vote or consensus. Reliability played large in our decisions.Quote:
Originally Posted by Dunk Mckay
When the schedule was shortened to remove this final event on Sunday morning, I was quite vocal in my objections.
Someone may have a better explanation for the change, my understanding was that shortening the event by a day was a large cost saving. It may have been part of the move to Michigan International Speedway, which is (I think), quite an expensive facility to rent and use?