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BillCobb
10-03-2013, 12:25 PM
I'm starting to see an increase in the number of self propagating threads from commercial software vendors who are making pitches for their products in the name of better engineering. I don't agree with the notion that blindly running commercial software amounts to an engineering education. (Last I checked this was supposed to be a university level educational undertaking). Some are now reposting material presented much earlier in time,` in the name of being current, when I feel that its only to keep their products in the sunlight.

Quite frankly, some of the claims being made and the techniques being recommended or passed of as 'technology' are just plain wrong. Its clearly aimed at students unwilling or unable to get educated on the subjects presented and wanting to get ahead of the rest by taking shortcuts around a classroom, laboratory, shop and track experience.

I'm not taking about classes being offered (even for compensation), just turn the crank products offered for sale which seem to have made up their own technology in the absence of facts or experience. I'm now even seeing fudge compensators for use when the facts don't line up with the computer outputs.

I hope the judges are seeing through this because this is a student competition, not a commercial venture. Let these vendors establish their value with results in the professional world, not in the minds of students or faculty here wanting to 'compete' as quickly as possible.

Sorry for the dispute, but I'm just recollecting a project GM once contracted out to a major local university involving rollover analysis. (Of course, the GM internal Vehicle Dynamics department would be too prejudiced to ever come up with a fair conclusion). Sure enough, their ADAMS results correlated perfectly for the maneuver being studied. Just for laughs, I used THEIR vehicle model to run two other ISO open loop handling tests in ADAMS. However the disappointment in these basic findings was not amusing to anyone on our side of the aisle. "They" had used only 1/2 of the MEASURED roll and yaw inertias in order to get their astounding rollover test results. When the 'correct' values were used, the correlation was ridiculous.

I'm unanimous with myself on this. All I'm suggesting is that these vendors be moved to their own discussion area, perhaps with a solid warning about the consequences of using their products.

Big Bird
10-03-2013, 12:41 PM
I'm right behind you Bill. I've been struggling to contain my annoyance at a recent thread hijacking by a commercial vendor pushing his / her wares on a participant asking questions about lapsims. Unsubstantiated, uninvited, unwelcome...

DougMilliken
10-03-2013, 12:44 PM
Bill -- excellent idea, for what it's worth you have my third (was: second -- I was still typing when Geoff's post went up). Another example of questionable behavior: we originally published team contact info along with the FSAE TTC finances spreadsheet--until a software vendor spammed every TTC member (6 or 7 years ago).

In my experience, design judges see through the use of commercial software as a "shortcut", at least in most cases.

To everyone else -- here's proof that Bill doesn't always write in riddles!

Edward M. Kasprzak
10-03-2013, 12:52 PM
Bill, Geoff: You're reading my mind. I, too, am disturbed.

And I'll second all of Doug's comments.

Big Bird
10-03-2013, 01:05 PM
Well Ed, I guess I will have to second your second, which seconds Doug's second, even though I was first...

Edward M. Kasprzak
10-03-2013, 02:15 PM
Maybe it's time to switch to a binary system. I give all of the above posts a "10". :)

ed_pratt
10-03-2013, 03:11 PM
I have to agree with this and 3rd... 4th?! the argument.
There has definately been a bit more of an infulx of these sort of posts recently, and while some have been useful and relevant to the OP, most are not.

I appricieate the desire to get(buy) a bit of software which will allow us to get some rapid experience with whatever we need. But, it does rather decract from the educational prcoess of making your own and failing to get it correct the 1st time around.

Throughought my education/research/working life I've invariably learned more from my mistakes than I have from my first time triumphs. I expect the students I teach to put in the effort themselves as I want their learning outcomes to be the same/better than my own. This is one reason I push as many as I can to take part in this competition.

Ed

BillCobb
10-03-2013, 07:19 PM
What would you all say about providing vendors with ad space which would have links to their wares? I don't mind knowing what's offered and available. But when the reply or thread directs procedures based on dubious theory or data, I get ill.

BTW: the change in roll and yaw inertia values done to improve the Tahoe rollover study results was substantiated by the claim that the measured values must be wrong and that a factor of 2.00 just made sense to change them when the correlation improved. This prompted me to adopt an expression about "large values of two" that later paid for itself in my many engineering discussions and presentations.

I hope this suggestion improves the forum credibility and reinforces it's purpose.

There are NO stupid questions.

exFSAE
10-03-2013, 08:29 PM
Valid points, for sure.

This general topic is a bit of a tough balance though. While FSAE should be an educational experience, I think it should educate a student to be a good practical working engineer. Seems often it's easy to get into the mindset in college of, "Well money is tight and my time is free... so I'll just do this all myself!" For simple stuff, sure. Or if you have a team of professional programmers, sure. But a lot of times in industry the best choice is to buy the off-the-shelf software, do your own validation, and go from there.

So how do you balance that out? What's the balance of in-house versus commercial? How do students at the FSAE level know what vendors are reputable?

I suppose I'm also speaking to this point entirely based on my own experience which had very minimal faculty adviser input. That's probably the best position to give direct feedback to the student team in what's worth pursuing and what isn't.

Kevin Hayward
10-03-2013, 10:11 PM
I add my agreement to those already in agreement.

I think in general a vendor thread group for all things software and hardware could be a valuable resource as well as a way to avoid in thread advertising. It would provide a place for suppliers to present their wares and give answers to student questions, as well as a place for students to search for existing solutions.

In general we should be encouraging students to understand the inner workings of both solutions and designs. Better still that they create their own, clearly understanding the trade-offs they are making.

- Instead of buying the Ohlins TTX44s or the Drexler diff, can you look at a longer term development program to develop something better?
- What are the implications of not including COG height in OptimumLap, or the relative importance of joint stiffness in ADAMS?

It would be great to see 500+ teams each with their own lap time simulator, custom designed power transmission, interesting suspension and steering concepts etc.

When I was involved with the OptimumK project we had to make a few early decisions. First whether it would be a general kinematics program where you could add any sort of linkage, or whether it would have inbuilt suspension types. Obviously we chose the latter, with the primary purpose to provide an easy to access product for the bulk of clients. It was the right call, but it meant that if you had a different suspension system than the ones we had allowed for you couldn't really analyse it. This is despite the fact that the maths behind it used very general solvers. In effect you were paying OptimumG to do a lot of the harder work, to allow you to iterate.

As a student that would mean that if you have a cool idea of how to make a better suspension system you just can't analyse it in the program. This is the same with any simulation software. Your solution landscape is bounded by the software creators imagination and/or resources.

I would say the same exists for hardware. There are plenty of great coilovers on the market. Pick an appropriate one and run with it. Except when you do that you are restricting yourself to one style of springing medium and one approach to damping. How about interconnected systems, rotary dampers, torsion bars? There are plenty of better solutions out there that involve not staying with what is available off the shelf.

I think a big part of the problem is that students believe that the vendors are much more capable and provide fundamentally better solutions than they are able to do. While this attitude protects markets it is just not true. Unfortunately this prevailing attitude is pretty deeply ingrained. When we rocked up with a custom design, manufactured, and tested interconnected suspension system in Oz 2004, we were asked (by professional engineers) what catalogue we got it out of, as well as being accused of breaking the rules by having the work done by a commercial company.

Don't design a lap time simulation because you either want a cheaper way out, or purely for the educational experience. Do it because in some way you can make it better, in a way which will help you improve your overall performance. Cut back the graphics so it can run more sims in the amount of time you have. Hook it up to an automatic optimisation routine. Investigate different tyre models. Look for n-dimensional pareto boundaries for multiple objectives, study the effect of vehicle path as a function of track width, investigate design concepts not normally offered in commercial sims, investigate the effects of uneven tracks surface and friction, etc.

In one year it is difficult to create something better than what is available off the shelf, but what about a 5, or even 10 year program?

Kev

dynatune
10-25-2013, 05:24 PM
Personally I do not think that there is any serious harm in indicating that some people can have also a commercial interest, as long as the comments of those people add, do help the ongoing technical discussion with quality info. Obviously "spam" is out of the question. I truly believe that any engineer should be capable of dividing a pure commercial message from a technical message. If he is not able to do so, the commercial message is the least of his problems. And if someone adds a link to some literature, to software or to a website, there might still be something to learn, there might still be something interesting to read on that link. Maybe not for all the very experienced and (as it looks sometimes somewhat prejudiced) senior members here, but for some of the young members a world of new information might come along. In fact I have received from this forum many messages from junior members who were very happy to learn about new views and most of all who were very happy to learn with a tool that allowed them to examine a few of their thoughts. Beyond that I like to mention that I have seen quite some rude comments from senior members versus novice engineers when they made "stupid" questions and even myself being a "junior" member have had the luxury of getting this treatment from people that did not have a quarter of my experience in real life. This is a behavior the senior members in this forum should dedicate attention to. In a scientific world all senior scientists should welcome every new member, how ignorant he or she may be at the time and form him or her to the best engineer possible. That is I think the mission of this forum, and I think we should all support that mission. Whether the educational info comes from commercial sources or not is of secondary interest. But I subscribe to the idea of establishing a new thread group about everything commercially available in the area of vehicle dynamics.That would seem to me an excellent idea.

Cheers

Dynatune