Anticipated rules changes

[TG]

Just curious as to what people think of the anticipated rules changes (http://www.sae.org/students/fsae-rulechanges.doc). I think I know who the first one is aimed at.

[TG]

Just curious as to what people think of the anticipated rules changes (http://www.sae.org/students/fsae-rulechanges.doc). I think I know who the first one is aimed at.

[Matt Gignac]

I think our front hoop from this year may be the cause for rule change number one. Off hand I think it was something like 30 degrees from vertical. It probably wasn't the best in terms of rollover protection, but that geometry helped with ergonomics and chassis stiffness quite a bit.

Wish I would've seen this before we started design... basically we gotta start the frame design over.

By the way, does anybody know for sure what kind of minimum angle we're looking at for the front hoop? Do you think the rules committee could answer that question yet?


Matt Gignac
McGill Racing Team

[Dan G]

We had to compromise w/ the judges on some of the wording around the foot protection. They conceeded that we met them as written, but they politely asked us to "fix it" anyways.

And its no mystery who's behind the industrial engine noise requirement changes.

[Chris Clarke]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">"¢ In Rule 3.3.5.2.C, the wording will be changed so that the Front Hoop Braces "must extend to the structure in front of the driver's feet"� not "should extend"�. </div></BLOCKQUOTE>

Here is Rule 3.3.5.2.C for the 2005 rules.

C) The Front Hoop braces must be constructed such that they protect the driver's legs and should extend to the structure in front of the driver's feet.

So from the sounds of this, we need to have the bracing (1" x 0.065") extend all the way to the front bulkhead. Is this what everyone else takes it as?

[Jarrod]

yes Chris, that is the intent.
we had a discussion with Michael Royce about this in 2003 at the australian comp, our front hoop braces only went to the "mid-bulkhead", where the front of the front wishbones come in, which is about level with the drivers shins. He didn't like it, and told us that was one of the rules that would be changed then. We had tubes running from the front bulkhead back to this node, but it was thinner tubing.

[Chris Clarke]

Jarrod,

We have had the braces run to our steering bulkhead since about 2000 (we have thinner tubes running to the front bulkhead), our front roll hoop also makes a 30 deg angle with the vertical. We havent had any problems with the judges regarding either of these for as long as I can remember.

Did the judges mention anything about the brace having to be one continous tube?

I briefly looked to find a date when the rules were posted last year, and it was mid-sept when they came out. That is a pretty long time to wait to make changes to the chassis, especially when it looks like there may be some significant changes to the rules.

[syoung]

The lateness of the rules publication gave us pretty big problems this year (when the new side-impact bar height was announced) - and we were only modifying last year's car, for the 200 Series of Formula Student (i.e. an otherwise fully-designed spaceframe, for 7 weeks after FSAE)!

[BStoney]

The addition/modification of the rule about the front roll hoop braces extending to the bulkhead is going to present design challenges to keep weight down. In our current design, it adds almost a pound by doing this (since it's 1 x .065 tubing).

Kind of sucks especially if you have a chassis design that is good and working, but that is engineering design challenges for you!

[Jarrod]

Chris,
no i don't think the tubes would need to be continuous, crossovers like some cars have on rear hoop braces would be acceptable i would imagine. It is a foot protection thing, so your feet and legs are completely enclosed in framework. The judges didn't say much about it, it was just Michael Royce as he was walking around the pits checking out the cars, in general discussion.

[Denny Trimble]

I hope they release the new rules soon, because we're starting frame design now, and I know of a couple teams that were building frames at this point last year, not to mention the teams who didn't make it to Detroit this year and who already have frames...

It would be nice to know exactly what the new footbox rules will be so we can go ahead without having to redo everything later.

[Matt Gignac]

We're one of those teams that has already started frame design, and I sent an email to the rules committee about some clarifications to these rules, or at least a good indication of what we can expect them to be (particularly concerning front hoop angle and footbox triangulation and front bulkhead support)

When I get a response, I'll post it here

Matt Gignac
McGill Racing Team

[Chris Clarke]

I think that they will have a few emails on the desk Monday asking about the new rule changes, I sent one yesterday asking the same thing basically.

[Erich Ohlde]

The bottom of the seat will be required to be no lower than the lowest frame rail or a TBD sized longitudinal tube that passes under the seat.

I think KU is in part responsible for this one. in our car the driver sits on around 8 layers of carbon which is the lowest part of the car http://fsae.com/groupee_common/emoticons/icon_smile.gif

[Pavan Dendi]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by jayhawk_electrical:
The bottom of the seat will be required to be no lower than the lowest frame rail or a TBD sized longitudinal tube that passes under the seat.

I think KU is in part responsible for this one. in our car the driver sits on around 8 layers of carbon which is the lowest part of the car http://fsae.com/groupee_common/emoticons/icon_smile.gif </div></BLOCKQUOTE>

No lower than the top of the lowest frame rail or no lower than the bottom of the lowest frame rail? I take it that the intention of this rule prevents the seat from being flush with the bottom of the car?

[Sam Zimmerman]

The Idaho team not only has a complete frame, but it has already been wrecked, had the front cut off, and rebuilt. I hope they saw the rule changes.

[syoung]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Chris Clarke:
I think that they will have a few emails on the desk Monday asking about the new rule changes, I sent one yesterday asking the same thing basically. </div></BLOCKQUOTE>
Anybody had a reply yet?

[Chris Clarke]

I haven't recieved a reply yet. I will post the reply here as soon as I get it.

[Matt Gignac]

Here's the reply I got:


FORMULA SAE
RULES CHANGES
FOR 2006
PART II

Further to the summary of 2006 Rules Changes that was published on the SAE website last month, the Rules Committee has done some more calculations and has had further meetings. Although the final text of the 2006 Rules is still being finalized, the Committee feel that as a number of teams are already designing their frames for 2006, it is appropriate that the current thinking of the Committee on certain major items be passed to the teams.

The Committee's direction is that:
· The maximum allowable angle of the Front Roll Hoop in side view will be 20 degrees to the vertical.
· Contrary to the announcement at the Awards Ceremony and in the earlier June posting, Rule 3.3.5.2.C will remain unchanged, and we will NOT mandate that the Front Roll Hoop Braces "must extend to the structure in front of the driver's feet."� Recent calculations indicate that it does not necessarily achieve what the Committee intends, and may be counterproductive. However, other rule changes to protect the driver's feet will be implemented.
· For instance, the first sentence of Rule 3.3.6 will state that "the driver's feet must be completely contained within the Major Structure of the Frame."� The intent is that the driver's toes do not stick above the frame, and we may even add words to make this explicit.
· The current thinking on the Front Bulkhead Support is that Rule 3.3.6.1.D will be deleted and be replaced by a new Rule 3.3.6.2, which would read something like:
o 3.3.6.2 Front Bulkhead Support
The Front Bulkhead must be securely integrated into the Frame.
A. As a minimum, the Front Bulkhead must be supported back to the Front Roll Hoop on each side by Frame Members at the top (within 50.8 mm (2 in) of its top–most surface), and at the bottom.
B. The Support must have node-to-node triangulation with at least one diagonal brace per side.
C. All tubes of the Front Bulkhead Support must be constructed of closed section tubing per Section 3.3.3. (This will be 1.00"� x 0.049"� minimum).
D. Monocoque construction requires an approved Safety Equivalency Form, per Section 3.3.2. The form must demonstrate that the design is equivalent to a welded Frame in terms of energy dissipation, yield and ultimate strengths in bending, buckling and tension.
The section on Impact Attenuator will then become 3.3.6.3.

Michael Royce,
Chairman,
FSAE Rules Committee

[TG]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Matt Gignac:
However, other rule changes to protect the driver's feet will be implemented.
·For instance, the first sentence of Rule 3.3.6 will state that "the driver's feet must be completely contained within the Major Structure of the Frame."� The intent is that the driver's toes do not stick above the frame, and we may even add words to make this explicit. </div></BLOCKQUOTE>

Interesting. I wonder if they will state it similar to the rollhoop requirements where it would be satisfied by either the teams driver with the largest feet or by a 95th percentile foot. http://fsae.com/groupee_common/emoticons/icon_smile.gif

[Chris Clarke]

I was just sent the same response, they are going to post it on SAE.org, but it will be the exact same thing as above.


Glad they told us now, our Front Roll Hoop is 30 Deg to vertical, and we are already well within the design/build phase. That could have killed us if they posted it later, as is, it makes for a lot more work.

[Chris Clarke]

I forgot to mention that they said they will be publishing the official rules in early-september like last year.

[Mike Cook]

Guys I have been working on next years frame and have ran into soome problems with the new rules. Specifically:

A. As a minimum, the Front Bulkhead must be supported back to the Front Roll Hoop on each side by Frame Members at the top (within 50.8 mm (2 in) of its top–most surface), and at the bottom

C. All tubes of the Front Bulkhead Support must be constructed of closed section tubing per Section 3.3.3. (This will be 1.00"� x 0.049"� minimum).

So, I need to have .049 ROUND CLOSED tubing all the way back to the front roll hoop on the bottom and top. For the top this really isn't a problem. But on the bottom we run two square tubes from the front roll hoop all the way up to the front bulkhead. We mill and drill the box tube for our suspension points. With this new rule it seems I won't be able to do this anymore, I will have to mount our suspension points on tabs outside of round tube. I'm not a big fan of this. Has anyone else thought about this particular problem or sent Mr Royce an email?

[Matt Gignac]

1" square tubing with a wall thickness of .035 has higher EI than 1" round tubing with .049 wall, so I'm sure you will be allowed to do some kind of equivalency calculations to use square tubes instead of the round ones.

I think 1" square with .035 wall ends up being a bit heavier than 1" round with .049 though.

Matt Gignac
McGill Racing Team

[Chris Clarke]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content"> So, I need to have .049 ROUND CLOSED tubing all the way back to the front roll hoop on the bottom and top. For the top this really isn't a problem. But on the bottom we run two square tubes from the front roll hoop all the way up to the front bulkhead. We mill and drill the box tube for our suspension points. With this new rule it seems I won't be able to do this anymore, I will have to mount our suspension points on tabs outside of round tube. I'm not a big fan of this. Has anyone else thought about this particular problem or sent Mr Royce an email? </div></BLOCKQUOTE>


As Matt said, you will be able to use square tubing provided that it meets or exceeds the minimum requirements of the round tubing. You will have to fill out and send in a safety structural equivelancy form (SSEF) showing that the comparison of the two. All they really want to see is the EI comparison.

In the 2006RulesChangesII document, they mention that the tube will be a minimum of 1" x 0.049". If this is the case that the minimum wall thickness is 0.049", then you will have to use 0.049" wall thickness tubing regardless, even if 0.035" square tubing is stiffer than 1" x 0.049" round tubing.

[Mike Cook]

My big concern is that the rules say it must be closed tubing. So even if I could use square tubing, having one side cut out of it for our suspension mounting points would void its use as a saftey structure, correct?

[Mike Cook]

This is the response I recieved from the rules committee:


Dear Mike,

Your questions are of general interest. Therefore, we have rephrased them in the answer below. We are planning to put the questions and the answers on the SAE website.

3.3.6.2 Front Bulkhead Support
The 2006 Rules specify that the Front Bulkhead Support members must be made from 1.00 inch diameter x 0.049 inch wall thickness round steel tubing.
Question # 1: Is the use of square tubing allowed?
Answer # 1: Yes. The use of square tubing for the Front Bulkhead Support structure will be allowed provided:
a. The Buckling Modulus (EI) of the square tubing equals or exceeds that of the baseline steel tubing. Note: For this application, the minimum wall thickness of steel tubing is 0.049 inch and of aluminum tubing is 0.125 inch.
b. The team receives approval after submitting a Structural Equivalency Form (SEF) per Rule 3.3.2.

Question # 2: Is the use of cut-outs in this square tubing to mount A-arms allowed?
Answer # 2: Yes. Cut-outs in the square tubing to mount A-arms will be allowed provided:
a. The Buckling Modulus (EI) of the tubing about the weakest axis at the cut-out equals or exceeds that of the baseline steel tubing.
b. The team receives approval after submitting a Structural Equivalency Form (SEF) per Rule 3.3.2.

Rules Committee,
FSAE

[kwancho]

http://www.sae.org/students/fsaerules.pdf
2006 rules are up.

edit: Not working yet. Soon, methinks.

[Dan G]

So it looks like this is the major change Cam Thai proposed to solve the turbo inlet vacuum issue...
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">AIR INTAKE SYSTEM
In order to give teams more design options the Committee is considering a major revision
of the air intake system rules. This change would permit the restrictor to be located
upstream of the throttle.
Since a change to the restrictor sequence would be highly significant, before it is adopted
the Rules Committee needs to fully understand all the potential ramifications and how it
might, or might not, affect the teams... </div></BLOCKQUOTE>

The common conception is that with a throttle after the restrictor, you could effectively have a very big tank of air between the throttle and the restrictor. The engine would run essentially unrestricted upon throttle tip-in, until the 'big tank' was sucked dry and you started breathing in as much as you were pulling through the restrictor.

So dyno numbers and even accel numbers should be relatively unaffected, but you'd have the possibilty of getting some added uumph powering out of corners.

I welcome the proposed rule changes. Most/all newer OEM turbo setups have a blow-through TB. And it should make things safer in the event someone blows an intake tube, since they'll no longer be at WOT.

[raska]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">The common conception is that with a throttle after the restrictor, you could effectively have a very big tank of air between the throttle and the restrictor. The engine would run essentially unrestricted upon throttle tip-in, until the 'big tank' was sucked dry and you started breathing in as much as you were pulling through the restrictor.
</div></BLOCKQUOTE>

On that note, myself and another team member were wondering if individual throttle bodies would become legal.

[kwancho]

New rules are up and working, and don't mention anything about putting the throttle behind the restrictor.

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">In order to limit the power capability from the engine, a single circular
restrictor must be placed in the intake system between the throttle and
the engine and all engine airflow must pass through the restrictor. Any
device that has the ability to throttle the engine downstream of the
restrictor is prohibited. </div></BLOCKQUOTE>

[murpia]

As an aside, is the 'no downstream throttling device' rule interpreted as prohibiting variable valve duration?

Ian

[Dan G]

Martin, good point, this would bring the question of ITBs out again. I almost want to suspect that they'll specifically ban them, as otherwise you'd be able to run nearly stock engine management with just a restrictor slapped on the inlet, which I don't believe the judges would want to see happen.

Alex, you're right. I pulled my quote from the "Notice of Proposed Future Rule Changes" section.

Ian, good question. BMW "throttleless" Valvetronic (http://www.bmwworld.com/technology/valvetronic.htm) type designs would probably be not far off if they left things open for it.

[jack]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by murpia:
As an aside, is the 'no downstream throttling device' rule interpreted as prohibiting variable valve duration?

Ian </div></BLOCKQUOTE>

i dont think the judges worry about teams designing and building their own VVD systems http://fsae.com/groupee_common/emoticons/icon_wink.gif

is there a date for the "new" intake rules? thanks, i am far to lazy to surf the SAE website myself..

[Tommo]

Alex,
See page 108
regarding proposed changes for 07

us aussie teams who will run cars first at australia under 06 rules and then under possibly changed 07 rules in US
could be interesting

tom

[murpia]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by jack:
i dont think the judges worry about teams designing and building their own VVD systems http://fsae.com/groupee_common/emoticons/icon_wink.gif
</div></BLOCKQUOTE>

OK, but has anyone actually received a rule clarification on this issue? Maybe it would depend on how big your plenum is....(!)

Ian

[kwancho]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Tommo:
Alex,
See page 108
regarding proposed changes for 07

us aussie teams who will run cars first at australia under 06 rules and then under possibly changed 07 rules in US
could be interesting

tom </div></BLOCKQUOTE>

Thanks. Never got that far.