1st revision of 2015 rules released

[Yannick]

I will also comment on the tires:

In my opinion spec tires are not a good idea. We have seen that different tire size can work well in different conditions. Let the teams figure out what is best for them. I think this diversity is important to FS.

I agree however that there is a trend to play a lot with the tires to get more performance out of them. This will lead to (even) more money being spent on tires, which is debatable if it is sustainable for the educational aspect (a lot of this knowledge is probably only useful for hill climbing). I don't see a problem with teams using tire softeners per se, it was allowed in my understanding in previous years. But know the extent of what teams are trying to do with tire softeners is getting out of bounds in my opinion.

To come back to the example, at FSA, there were 3 teams that for sure used a lot of the stuff. As Julian said, some of the tires were wet after the tire protectors were taken away (definitely not water). Also after doing some suspension checks before endurance (and thus touching the tires) my hands were full of rubber.

The problem is more, as Julian pointed out, that teams have started to have different sets for Acc., Skidpad, AutoX and Endurance. This is, again in my understanding, not allowed. While it originally was the same compound, they are not anymore due to the treatment. A similar / same issue is possible with a team that has self made tires. How do you know if they have the same compound on all dry tires for example?

I think the suggestion by Julian makes a lot of sense. Like this learning about tires and tire modification is not prohibited but there are some bounds given.
Another way of handling this is how it is already done at FSG (for custom tires only), where you have to present all tires you have with you. Then the officials selects random sets of four which are marked accordingly.

Cheers
Yannick

[apalrd]

In my experience, Michael and Andrew, complaining about it in this forum does not change anything. You should take it up to the rules committee. When FSG announced some serious Aero restrictions for 2014, the guys from Monash wrote a nice document where they explained why the rules are too strict - not purposeful.

How can I contact the rules committee for Formula SAE in the US?

The Formula Student Germany website clearly lists the members of their board and rules committee, and an email to contact all of them by. In fact, their Contact page directs me to their Officials page 'for specific issues', and suggests emailing the relevant people directly.

For Formula SAE, the only page I see is http://students.sae.org/cds/formulaseries/contact.htm which lists the names of the manager of each program, and a single email to direct all inquiries related to CDS. Surely this can't be the place to email the rules committee specifically?

[JulianH]

I got an answer from Kaley (kzundel@sae.org) about the ridiculous 300V limit. I think she forwarded the mail and came back to me.

It took only a week, sadly my reply 14 minutes later (August 19th, 2013) was never answered.

Another possibility would to contact Tobias Michaels (michaels@Formulastudent.de) from FSG. He is responsible for the electric rules (maybe he even was part of the ETC rules implementation...). He is a great guy and forwards your letter to any responsible from the states.

[DMuusers]

So I'll add in my say on tires:

- On the topic of self-designed tires and different compounds: First I want to say that we (TU Delft) haven't competed on different compounds at any competition that we attended, although I heard there were some rumours flying around. It's understandable that these rumours are there, since you can't really see if the acceleration tires are the same compound as the scrutineering or endurance tires. During scrutineering we also handed in a signed document by our sponsor stating that all slicks were the same compound aswell as all the wets. I also think people underestimate how hard it actually is to create a compound that is currently better than the Hoosiers, although it's not impossible. However, I don't think teams (custom tires or not) should be prohibited to use more than one set. Mainly because anything can happen during competition to the tires rendering them useless, for example a puncture. It would be extremely demotivating, and I think also not in spirit of fair and equal competition (though that's debatable).

- On the topic of tire softeners: using tire softener actively alters the compound. Since the rules state all slicks should have the same compound, tire softeners are (in my opinion) banned since you cannot show that all tires are the same compound after using it. Besides, it can be extremely dangerous since you're basically degrading the molecular bonds of the tires, which can cause them to rip apart.

- On topic of scrutineering the tires: in FSG they tell the teams with custom tires to bring them all so they can decide which 4 are a set (in case of multiple tires). I think this is a great solution and should also be applied to all teams. This makes sure that no team uses at least different amounts of tire softener. The downside is that heat cycle testing and such become obsolete, however I feel that with the Hoosiers at least the fewer heat cycles the better.

[JulianH]

Daniel,

I heard the rumours in Germany as well. Someone of your team said that you have been testing different compounds, so it's not a long thought from "they have different compounds" to "they'll use different compounds". I don't insinuate that Eindhoven or Delft really did that, but you understand that this is something obvious to think... I think the German solution: "We decide which tire is used when" is just perfect to end such rumours.

About multiple sets:
I still think that it is a good idea to limit the number of tires to one set. In case of a puncture or something strange happening, of course teams can rescrutineer a spare tire...
Why do teams need more than one set?
If we leave out the Endurance, you don't drive more than 3-4km at an event. I think 22+4km should be an easy task for a tire. Even if you customize it.

I know that it is a large advantage for a team like yours to really develop a tire just for 22km instead of like 100km for a regular Hoosier tire. But you still can make it work with a bit less advantage...


If you ban tire softeners or what ever chemicals because they are "dangerous", one would have to ban student developed tires as well, because you also can't assure that they did not play with such stuff. Not every team has a big partner like Delft/Eindhoven/Darmstadt.. maybe one day there will be a team coming to competition with KARACING or TUFAST tires.. we don't know.

The team with soaked tires is running those since 2010 at least and there was never a tire rupture (in fact I never seen such a damage at an FS event)... in the last 5 years I saw at least 10 flying wheels and 5 burning cars which are both probably more dangerous than a tire rupture..

[DMuusers]

Hi Julian,

we tested different compounds yes. I actually have written 2 reports of our compound tests (iteration 1 and 2) and have discussed this during engineering design at all competitions we attended. At the end though we decided on one compound to go on our slicks. We actually don't have any tires with different compounds lying around for the DUT14 because they were simply never made (I should know, I designed them).

I also agree that maybe a limit of 2 or 3 sets seems very reasonable (1 set acc, skid, autox, 1 set endu. or 1 set acc, skid, 1 set autox, 1 set endu.) and then have the scrutineers pick the sets for which event. Right now one set of our tires should last an entire competition quite easily, but if something is wrong with one of them, it could be that we (or if some other team had a puncture or whatever with this rule) wouldn't be able to compete properly.

Another thing about the development of compounds. It's not something that you just 'do'. I don't think any team will be able to do this without a significant and highly specialized sponsor. There's a lot of reasons highly trained specialists design these compounds so therefore I'm not afraid that a team will make their own tire without a sponsor. You can always add a rule that the tires must be produced by an official tire company if you really think students can do this on their own.

How do you know that teams that used tire softeners have never had a rupture? It's something most teams wouldn't like to share on facebook anyway

[apalrd]

I got an answer from Kaley (kzundel@sae.org) about the ridiculous 300V limit. I think she forwarded the mail and came back to me.

I submitted an inquiry to the rules committee via Kaley. Hopefully the RC clears up the torque vs throttle rules, as well as a few others from the ETC section.


On a slightly related note, MCoach and I are also putting together an analysis of the noise output of stock production cars, to submit to the RC regarding the new 100 dBC idle rule. As it is, we have already found 2 cars which fail during warmup-idle. This is an issue which affects all teams, and I know we'll have quite a challenge meeting the 100 dBC idle with our muffler weight target on our single cylinder engine.

[Kevin Hayward]

Yannick,

Please note the suggestion was for homologated tyres rather than spec. This would stop custom tyres, but everything else would be okay.

I completely agree with the 4 tyres per comp, maybe with up to 6 allowed to account for a puncture(s) They can be randomly numbered by a scrutineer such that the first four must be used until damage occurs.

...

I am not sure that custom tyres are legal as per the current rules, and am conflicted by their use. On one hand it is great to see teams going that far, and engaging industry. However it seems pretty clear that without external specialized knowledge that it is not possible to design and construct the tyres. To quote Daniel:

"I don't think any team will be able to do this without a significant and highly specialized sponsor. There's a lot of reasons highly trained specialists design these compounds so therefore I'm not afraid that a team will make their own tire without a sponsor."

This looks like a violation of A6.1 and A6.3. For other difficult design areas (such as custom engine) it has been proven to be in the capability of a team to do the complete design and fabrication inhouse.

I think if such an engagement was to lead to a FSAE tyre available to all who ask it would be a different matter, as it is students assisting in the development of a commercially available product. I would say this occurred with Goodyear previously, but obviously with almost no input on design (more on feedback and testing). In this scenario you can have students actively involved in tyre design and development, but without a violation of the rules. The teams involved in the development would still have sole access to the information they developed if they wished.

...

This is the interesting thing about new rules. You think that the announced changes will have the biggest effect (i.e. big aero changes), but I would suggest that by making teams aware of tyre treatments and putting bounds on their use will have a much bigger impact over the full field. Any serious team should be considering what to do. Previous rules have banned it outright, maybe it has been seen in later rules as a matter of interpretation, but now there are clear guidelines of when tyre treatment is okay.

Kev

[Jan_Dressler]

I.C.1.7.1 Restrictor, supercharger, throttle ONLY - I understand the reasons for this change for the turbo designs, but with bypass/recirculation valves etc banned, this now creates a big issue for any positive displacement supercharger, which are quite happy to operate in partial vacuum. Would a propriety internal relief or bypass valve be considered illegal?

I agree. IC1.6.1/1.7.1 + 1.7.3 (Why should the use of recirculation valves be prohibited?! I honestly cannot find any reasonable motivation for that. Open blow off valves, okay, to prevent any chance of getting air in after the restrictor, but "closed" systems? Does not make any sense at all to me) + 1.16 (not more than 10% throttle during braking) basically prohibit the use of positive displacement superchargers. Completely. Turbochargers are less affected, but here the recirculation valve would have been needed as well, as an anti surge valve and simply to keep the turbo spinning, when the throttle is placed behind (and no open-throttle-anti lag system is allowed).

Why change the throttle position, which encourages the teams to use turbochargers, and then create IC1.7.3 which in combination with 1.16 makes the use of all kinds of turbo- or superchargers near senseless? I don't get it.

[Kevin Hayward]

I was just browsing through the old rules (much easier because they are much shorter). I had missed the obvious:

"No traction enhancers may be applied to the tires after the static judging has begun."

Which clearly makes traction enhancers okay to use. It was my old and incorrect interpretation that led to me thinking otherwise. Please disregard my comments about this being a change. It also represents an increase in safety in the just released rules.

Apologies,

Kev