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Thread: Two simple rules to improve results.

  1. #1

    Two simple rules to improve results.

    So I've been giving advice to my old team, and on occasion members of other teams if I strike up a rapport with them at comp.

    I've also spent many a Sunday afternoon watching car after car breakdown, either at Silverstone or watching Hockenheim live on Youtube.

    Everyone is unhappy about the amount of teams that breakdown in the grand event. It is, to some extent embarrassing, and to listen to the commentary at these events, it is expected.

    But no-one is actually doing anything about it.

    I mean seriously, no-one. Sure the IMechE will say they run the "Learn-to Win" event, and FSG have a technical debriefing for team members coming back next year, and there's Pat's corner, and the 'Learn and Compete' book (best attempt so far, but no longer available and needs updating). But these have been going for years no, things aren't getting better.

    Some will argue it's up to the teams. It's always been up to the teams to build a car that works! But the current rule book makes them build cars that don't!

    So I've had enough. I have two simple rules, that I believe will make a significant difference to the situation.
    (Not that I think these will ever be implemented under the current regime, but hey ho).

    New Rule Number 1:
    -When weighed, your car must have a minimum mass of 200kg.
    10 points will be deducted for every kg under this threshold.

    New Rules Number 2:
    -All teams have the option to submit an advanced video of their running car up to 30 days ahead of the start of the competition.
    20 bonus points will be awarded for submitting on the deadline date, for each additional day before this deadline an additional point will be awarded, up to a maximum total of 50 points.
    The video must show the car completed with all bodywork and include clips demonstrating the presence of all safety features (driver harness, head rest, impact attenuator, brake over travel switch).
    A member of your academic staff must sign off to say that all systems demonstrated/shown in the video are indeed functional and the final versions intended for competition.

    The problem with 90% of teams that DNF, or worse, DNS at comp, is that they worry too much about the wrong things. Chasing fractions in performance instead of reliability and timeliness.
    Offering a minimum weight will take some of the pressure off weight saving, so corners won't be cut where they shouldn't be.
    Offering Bonus points for being able to demonstrate a running car in advance of the competition (but about as late as any good team should be looking to have a completed car), will add even more emphasis on the time pressures this sort of project entails.


    A few preemptive arguments.

    -Why 200kg?
    200kg is about right for a basic space-frame non-aero car, that doesn't break the bank and is relatively easy to manufacture.

    -Most of the teams that break down don't build cars less than 200kg as it is.
    This is true. But they'd like to. Most of these teams are in the 200-250kg region. Currently each year they talk about making their car as light as possible, so the next year can go even lighter, and ultimately make that 175kg car. If they know they can't go below 200kg, they won't be pushing so hard to cut mass out of every single system.
    A lot of teams in the 175-200kg region, with mostly well built cars breakdown more than they should (you know who you are). They go from top 10 at one comp, to bottom half the next. They are inconsistent because each year they try to shave that little bit extra weight to make their car that little bit faster. Ultimately they probably end up weighing the same because they fixed reliability issues with weight in one area, while doing the opposite in another, continuing the cycle.

    -But if there's no longer a drive to save as much weight, won't it make choosing an engine easier? Everyone will just run 4 cylinders! This competition is supposed to be about having total freedom of design choices.
    Firstly, I don't think they will, I've seen plenty of singles and twins over 200kg, especially full aero cars.
    Secondly, as for the total freedom of design choice argument, I think that's a bit ridiculous. It's an engineering competition; real world engineering is flooded with restriction and limitations. Yes, it's good to give lots of freedom so all the cars aren't the same, but we already have a pointless maximum displacement rule, which limits choice for no good reason. As I've said I don't think this will limit choice, perhaps some teams will sway a different way, but in the end haven't 4cylinders' proven to be more reliable anyway? Isn't that what we want?

    -Bonus points mean a team could theoretically score more than 1000
    Yes, so? Team with most point wins. How does that change anything?

    -Demonstrate break over-travel in a video? You could just film someone hitting a non-wired in switch, with someone off camera hitting the master switch to cut the power. What about all the safety features, they could just mock them up so save time.
    Yes, but that would be cheating, and for so little gain (how long does it take to wire in a single switch? Not 24 hours). Plus they've had a member of the academic staff sign it off; in most cases, if they were found to have lied this would have severe consequences for their job, they wouldn't take the risk.

    -But what about dry vs. wet weight? What if some teams have empty tanks and no oil?
    I'm not interested in discussing the semantics of this, that's not the point. Ultimately you have to be over 200kg at all times during the comp, be that in scrutineering, before design judging, or in parc ferme after endurance. Heck, it wouldn't be hard to have some roll on roll off corner weights set up at the entrance/exit of each event (although that might be excessive).
    Last edited by Dunk Mckay; 03-12-2017 at 06:17 PM.
    Dunk
    --------------------------------------------------------
    Brunel Racing
    2010-11 - Drivetrain Development Engineer
    2011-12 - Consultant and Long Distance Dogsbody
    2012-13 - Chassis, Bodywork & Aerodynamics manager

    2014-present - Engineer at Jaguar Land Rover

  2. #2
    Build a 150kg car, put 50 kg of tungsten right below the CG. Better yet, have it adjustable so you put it rearward and high (maximise long. load transfer and attempt to lift front wheels) for acceleration, and then low and under CG for every other event.

    I think the intent here is fine, though I believe it would just introduce a different fine-tuning objective.

  3. #3
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    Winning Strategies.

    Allow me to add, based on my experience, that choosing a smooth driver/operator can be an important factor in vehicle durability. Someone who is hard on the steering, throttle, brakes, tires and suspension springs will cost you in long runs. The reward(s) for longevity are big for ANY product design.

  4. #4
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    Dunk, it has been my experience that most of the cars that break or don't start are already over 200kg.
    Any minimum weight rule is flawed because of the various car designs. A composite, 10" car with a single cylinder engine vs
    a spaceframe, turbo 600/4 on 13" wheels and with a full aero package can not be bunched together.
    Those choosing a lightweight, low power engine do so to save weight...don't ask them to add 50kg of ballast and become instantly uncompetitive.
    Several competitions, including FSG, already have the requirement to submit a video of the running car.
    The old dodge of submitting a dry car (even to the extent of empty batteries) was identified long ago.
    At FSG there are penalties if your car weight changes significantly during the event...and they do additional weighing!

    Remember, FS/FSAE is an engineering competition with a motorsport theme, not a motorsport event.
    The intent is that you make your mistakes and cockups before you are inflicted on some poor employer.
    That seems to work well as the lesson learned by all those members of the DNF teams is KISS!

    Pat
    The trick is... There is no trick

  5. #5
    Fully agree with Pat. (Could be the first time I think )

    The 200kg rule kills the "Delft cars". Even if you can put heavy stuff very low in the car, you will see the massive power downside of a single-cylinder. I think they won't be competitive anymore.
    I think that kills a lot of the possiblities.

    The "present your car X days before competition" is a great rule. I like how it is used in FSG. Maybe it is possible to be a more strict on this and give out penalties.
    What I don't like with your rule is that it would promote even shorter Engineering cycles, less imagination and more "carry over". Teams should push it also between the years!

    Julian
    -------------------------------------------
    Alumnus
    AMZ Racing
    ETH Zürich

    2010-2011: Suspension
    2012: Aerodynamics
    2013: Technical Lead

    2014: FSA Engineering Design Judge

  6. #6
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    I agree with the pre-competition video idea. I have heard that the competition in Japan has some kind of rule about that and it has been successful. The points bonus is an idea that I haven't heard before, but I think it would be a good thing.

    Minimum weight rule, I don't think will be effective. As others have said, a big proportion of the cars that fail endurance are already over 200kg. The problem with it is, being 200+kg does not guarantee that all the weight has been budgeted appropriately into every critical part for equal & sufficient safety factors. There's just no way around the fact that ultimately, if you want to see higher endurance success rates, it depends on the teams to do better engineering. A single minimum weight regardless of engine type, chassis type, wheel size, presence of wings, etc, is very arbitrary too. A car that's 190kg could add a 10kg wing package to meet minimum weight, does that make it any more likely to complete endurance? No, likely the opposite. A 200kg minimum weight would also kill some design freedom and make certain concepts uncompetitive, which I think is a bad thing.

  7. #7
    I'm not denying that a 200kg weight limit make certain designs uncompetitive. It absolutely does. My argument is: so what?

    The aero limitations opened up a number of years ago, all of a sudden you had to have aero to be competitive.
    They've been constrained back a little since then, but other than by default, I don't think it's possible to win a competition without a proper aero package.
    That's a a change that basically ruled out any teams that didn't have the resources (money, skills or manpower) to build a design concept with an aero package.

    So "killing" certain design concepts is no justification not to change things.
    If anything, in this case, it would probably level the field a little. Decent smaller engines are harder to come by, especially for teams in certain parts of the world.


    Additionally, based on 200kg it only really kills the the design concepts of teams that currently reiterate the same successful design every year. If the teams really are as good as their car, and not just resting on the laurels of those that came before, then changing their concept shouldn't be an issue.

    Pat, as I stated in my opening post, the cars that fail the most are indeed already over 200kg. But these teams have all been lead to believe, by the culture of the competition, that mass is really important. I don;t know of many officials doing much to dissuade that idea. Weighing in immediately before Design judging at FSG for example is extremely misleading. All else being equal, and within a reasonable mass range (180-250kg) a kilo is worth maybe 1-2 points at comp, based on dynamic events. But in design judging it can really depend on the judges; I don't think any DJ would award points for intentionally having a heavy car, but many would penalise you for not trying to be as light as possible.
    At least with some sort of limit, the discussion does from: "Why didn't you try to have the lightest car possible?" to "Why didn't you aim for the 200kg limit?" Which I think is a much more interesting conversation.

    Also from the whole ballast point of view. The question becomes: "I see you can built a very lightweight car. But is ballast really the best use of the remaining mass available?"
    (I can think of a few ways that would increase performance much more than ballast that are currently legal).



    If we really are saying that allowing design freedom is an untouchable objective, second only to safety requirements, then there are pages and pages of rules that need to be stripped away. Rules that are far more restrictive than a minimum weight limit, that don't offer new, different challenges but simply close doors on different opportunities and bias the competition towards teams with more resource who build the same car year after year.

    The 200kg mass limit wouldn't need to be fixed either, it along with a few other specific variables (e.g. aero packaging) could be adjusted every couple of years as a matter of course. So no team would be able to sit back and relax with their carry over concept, simply tweaking it for each minor rules change.
    In some cases this does play into the hands of teams with the resource to invest in new development every year. But on the flip side, on occaision, a cheaper, heavier, simpler car, with no aero, would be given a fighting chance.
    Dunk
    --------------------------------------------------------
    Brunel Racing
    2010-11 - Drivetrain Development Engineer
    2011-12 - Consultant and Long Distance Dogsbody
    2012-13 - Chassis, Bodywork & Aerodynamics manager

    2014-present - Engineer at Jaguar Land Rover

  8. #8
    Narrowing down the number of ways to make a bad car sure seem enticing, but when teams still put rod ends in bending, a weight rule or first drive video won't prevent failure. Time will find them and won't be kind.
    'engine and turbo guy'
    Cornell 02-03

  9. #9
    I am a fan of requiring a video some time before the competition. However, the idea of 'bonus' points really doesn't end up working. All you've done is move the deadline to the time of maximum bonus points. So instead of 30 days before the competition, teams will have their cars done 60 days before the competition. That may increase reliability, but it doesn't create bonus points. It just makes the competition out of 1030 points rather than 1000.

    I don't have the time right now (a couple weeks and I'll come back to this) to examine previous year's results, but it would be interesting to see endurance completion rates at competitions that require video of the car driving beforehand to competitions that don't. That metric would be the one to use to justify such a requirement, right?
    Jay Swift
    Combustion Powertrain
    Global Formula Racing 2013-2014

  10. #10
    Dunk,

    You do not get it!

    F= Ma. For a given lateral acceleration the more mass the more force, therefore the more compliance (and less driver control and confidence) and the more effort of each suspension members, chassis etc..

    To avoid deformation and possible rupture you have 2 solutions.

    1. Make the chassis and suspension stiffer which add more mass which add more force which add more causes for compliance and possible rupture. That is the ugly crescendos towards disaster
    2. Design smart. A good distribution of the tire forces and moments on the suspension elements and the chassis (just as an example think about the tire lateral force acting on a wishbone that has one arm perpendicular to the chassis and the other at 45 degrees or on 2 arms that are both at 45 degrees) will prevent concentration of forces and there fore decrease the need for heavy components. There is a reason why design judges ask students to exhibit the load path studies (forces on each suspension elements for different load cases: skip pad, braking, acceleration, combined longitudinal and lateral acceleration etc...)

    At 2011 FSG I judged 2 cars that had exactly the same concept; electrical 4WD one was 80 KW the other 82 KW, no big difference), no wings, tubular chassis. One was 145 Kg the other 230 Kg. More than 50 % of difference for the same concept.
    When I asked the 230 Kg car team why their car was over 50 % heavier for the same concept, their first answer was "but we lost 30 Kg compared to last year" ...which did not answer my question.
    I pushed them to come with a better answer. They told me that the car was heavier "because it had more batteries" I asked them why they needed more batteries and the answer was that with the same amount of batteries than the 145 Kg car they could not finish the endurance.
    The question then became why do you have more energy consumption and the answer was ".....because the car is heaver!!!!...."

    The heavier a car is the heavier it will have to be. The lighter a car is the lighter it can be.

    If a rule about weight should be created it would be that car over 200 Kg should be penalized.

    It is possible to make car that is light, stiff, aesthetic, easy to manufacture and maintain. To do that you need to
    a. inspire your self from nature. God is the best designer; n egg with a shell of 0.3 mm thickness can sustain a force of 450 N in its vertical axis? Have look at the FEA of a tree branches and roots fibers....
    b. Form follows function. 1 Functions and then 2 Form, not the other way around. And that is one of the traps in which many, many students fall: they start designing the car before having a complete list of the functions that the part is supposed to fulfill.
    The typical example is the team that starts designing the chassis without having determining where there suspension pick up points will have to be. You will often see on that type of car the suspension points or the rocker or damper attachment right in a middle of a tube... which create compliance.....that you can wrongly fight with stiffer and heavier tubes.

    Designing an heavy car is going against all the efforts that the automotive and aircraft industry is trying to reach. More energy consumption. more recyclability issues. Not what a Design competition is supposed to achieve.


    As far as the video way before the competition it is a rule that is already applied in Germany, Japan and India.
    Claude Rouelle
    OptimumG president
    Vehicle Dynamics & Race Car Engineering
    Training / Consulting / Simulation Software
    FS & FSAE design judge USA / Canada / UK / Germany / Spain / Italy / China / Brazil / Australia
    [url]www.optimumg.com[/u

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