Flexible wings 2011

[bot6]

One of those materials could be a simple 15°/-15° carbon fiber and epoxy resin composite.

Basically, you have two elastic moduli working together here: that of carbon fiber (very high) and that of the epoxy resin (much lower). As you pull on the laminate (along the 0° axis), the resin will start stretching, but the reinforcement fibers will just orientate themselves along the strain axis due to the relative "softness" of the resin. Once they are better aligned with the strain, the fibers will start to take some of the effort and suddenly, the material will become much stiffer.

It really all depends on the resin you use and how much you cure it, and the orientation of your fibers relative to the load.

[vall]

Shoot the messenger...

The FIA mandated a slot-gap separator in 2006 when Ferrari was letting the rear wing of the 248F1 flex under load. That, as they say, was that.

So, how about suspension wires to maintain a rigid front wing?

UGH!

A skid block would be better, but how would you allow for rubbing on kerbs?

I suppose one could stamp on any creative engineering by mandating a stiff core to the wing that ran from end plate to end plate. Then we would have a spec series. If you want that then watch Indy.

well, you are not quite right. The wires will only prevent the wing from flexing, but the designers can still come up with very different elements of the wing, no? So, this may the the only viable solution of this issue.

[Richard]

The rule, as it actually stands, IS breached. Not the bending test one, but the ground bridge one (3.15) and the "no aero device under the reference plane" one.

Quoted three times in this thread already.

The dimensional limits only apply when stationary. All parts of the car move and deflect under loading - unless they are infinitely stiff. There is an allowable deflection defined by a load test. RB pass that test. RB comply with the rules.

Cars frequently bottom out, are you advocating prohibition of that too?

[marekk]

The rule, as it actually stands, IS breached. Not the bending test one, but the ground bridge one (3.15) and the "no aero device under the reference plane" one.

Quoted three times in this thread already.

The dimensional limits only apply when stationary. All parts of the car move and deflect under loading - unless they are infinitely stiff. There is an allowable deflection defined by a load test. RB pass that test. RB comply with the rules.

Cars frequently bottom out, are you advocating prohibition of that too?

Car bottoming out makes just some nice sparks, car without FW makes this:




I'm advocating prohibition of that.

[Formula None]

Here is one possibility I cooked up which uses the mechanics of a preloaded spring plate (in the form of a composite plate) to give a non linear deflection response.

http://img59.imageshack.us/img59/6998/flexiwing.jpg

Tim

1. That's a great illustration & idea, Tim. I wonder if it can account for the torsional rotation / changing AoA, as bot6 & some others are suggesting (what some of us are thinking comes from the nose cone drooping).

2. Would it be easier to have a wing that deforms linearly and can still pass the 100kg FIA test, and a nose cone that deforms linearly, working in concert to give us the overall movement we see?

3. What's the simplest possible explanation? The change of rake we see might have nothing to do with the nose or fiber orientation or preloading and might be inevitable due to drag from the increasing ground effect. Wing droops transversely (simple 2D bend) --> ground effect increases --> drag pulls wing back and decreasing pressure pulls leading edge down. Could this explain the complex multiaxis flexing while still using "simpler" or typical CF layup?

[marcush.]

I go back to my original idea:
place a laser beam on the teatray aimed at a target fixed to the front wing centre portion and some point on the outside of the front wing(not shadowed by the front wheels).either take the TV camera to actually see the laser beam moving up or down as either teatray or wing move or have the target as a optical sensor and as soon as the beam does divert from the sensor the car gets black flagged.
Thats simple and enforcable at short notice.Give some tolerance for time say longer than .5s and we have it sorted.

I don´t think it is possible for Neweys gang to design a wing that deflects synchronous to the teatray yet ..

[Lindz]

Yes, you can scrutineer every wing by putting them in a wind tunnel. As I've mentioned before, that would be onerous.

Better to accept the rule as it currently stands and allow ingenuity to find a way to work with it. Surely this sport cries out for ingenuity? Infinite testing will only result in a serious of identical cars with no room for creativity at the boundaries of legality?

Its the same issue about the Melbourne car park run off. Its always been there, cars always use it, the brave venture onto it and win, the foolhardy stray onto and look like idiots as they rejoin over the grass.

Enjoy the ambiguities, that's where the creative folk are found.

The rule, as it actually stands, IS breached. Not the bending test one, but the ground bridge one (3.15) and the "no aero device under the reference plane" one.

Quoted three times in this thread already.

The one about "absolutely no flexing" has been scrapped as it was inapplicable.

I agree with both of you. Here are my opinions:

-I think if RBR weren't concentrating on THIS development, they would concentrate on something else. They are a very creative group of people, led by the most creative designer in F1.

-You can't DQ a car because you see pictures of it doing something 'illegal'. You have tests to deem what is and is not illegal. If the car or parts pass this test... well, then what? You say it's legal in real-life testing, but illegal in pictures?

-When in motion under racing conditions, you are contending with unpredictable (or at least unverifiable) forces of nature. How do you test this? Again... you cannot DQ a car because of photographs (or even video).

-You can change the rules (which they did), but you risk the 'offenders' (RBR) from developing the part to pass and eventually do the same thing. You also risk other teams that you deem to be 'not offending' (let's say... Force India) from failing the new tests and having to go back and re engineer their 'non-offending' part.

-Last year they had an illegal suspension trick between quali and race. And then an illegal blown diffuser. And then an illegal front wing. It's a bit of cat and mouse. Excuses always fly as to why someone is better than someone else. Rarely does anyone say "Oh, yeah RBR are just doing a better job designing an F1 car."


I say it's a brilliant bit of F1 engineering. In an age when most fans complain all the cars look the same and progression is usually frowned upon, i find it refreshing. In fact, I find the whole RB7 to be refreshing. At face value it's not a 'revolution' like the MP4-26 or R31, let's say, but in engineering and design details, it's very progressive. Exhaust/cut rear floor, sidepod packaging, Entire rear-end package and design (pull rod, gearbox, bodywork, diffuser), front wing, etc...

It's innovation and skirting the legal limit. Just like F1 design should do.

[marekk]

3. What's the simplest possible explanation? The change of rake we see might have nothing to do with the nose or fiber orientation or preloading and might be inevitable due to drag from the increasing ground effect. Wing droops transversely (simple 2D bend) --> ground effect increases --> drag pulls wing back and decreasing pressure pulls leading edge down. Could this explain the complex multiaxis flexing while still using "simpler" or typical CF layup?

Don't think so. Actually drag reduces with wing lowering. What's increased is torque between aerodynamic center of pressure and FW pillars. Additionally, with increased angle of attack, center of pressure moves fore and torque increases further.
All you need to get wing twisting under load is to build it not stiff enough in longitudal direction. In fact, all aircrafts wings twist for some extent, and before it was understand (WW II), many accidents related to wing's twisting forces happened.

[JohnsonsEvilTwin]

The rule, as it actually stands, IS breached. Not the bending test one, but the ground bridge one (3.15) and the "no aero device under the reference plane" one.


-You can't DQ a car because you see pictures of it doing something 'illegal'. You have tests to deem what is and is not illegal. If the car or parts pass this test... well, then what? You say it's legal in real-life testing, but illegal in pictures?

-When in motion under racing conditions, you are contending with unpredictable (or at least unverifiable) forces of nature. How do you test this? Again... you cannot DQ a car because of photographs (or even video).

Its blatant.
This is the problem, it can be seen outside the car and inside the car. What you say is unpredictable forces of nature, I say is carefully thought out and planned engineering done in such a way as to gain an advantage.
How else can you explain it?

[bot6]

The dimensional limits only apply when stationary. All parts of the car move and deflect under loading - unless they are infinitely stiff. There is an allowable deflection defined by a load test. RB pass that test. RB comply with the rules.

Cars frequently bottom out, are you advocating prohibition of that too?

If you had read me, you would have known I am NOT talking about the bending test, which the wing passes.

I am talking about a rule that says no aerodynamic device should be designed as an attempt to bridge the gap to the ground (it's the rule that outlawed skirts). And it is forbidden to do so under any circumstances. I believe a running car is a circumstance, right? So it's included under "any circumstances".

The second rule it breaches is the "no part should be under the reference plane" rule. Again under any circumstances.

So go and read the complete text of technical regulation 3.15, and maybe then we can talk.

-You can't DQ a car because you see pictures of it doing something 'illegal'. You have tests to deem what is and is not illegal. If the car or parts pass this test... well, then what? You say it's legal in real-life testing, but illegal in pictures?

-When in motion under racing conditions, you are contending with unpredictable (or at least unverifiable) forces of nature. How do you test this? Again... you cannot DQ a car because of photographs (or even video).

Why not? Photographs are admissible evidence in criminal cases, why should F1 refuse such evidence? They are perfectly acceptable evidence if used in the correct way, and reverse engineering a shape from a photograph is not very difficult.

When the rule says "under any circumstances", that takes into account the "forces of nature" you're talking about. Photographic evidence should be accepted under such conditions. That's really up to the Stewards and to Whiting at the end of the day.

As for redesigning the test, there are ways of doing that in a better fashion than what they did last time (they just increased the load to a value still under the real aerodynamic load experienced by the wing).

Having a multi point load test would sort this (load three points along the endplate), using the same rig as they are using right now, so no extra cost and no delay for building a new rig.

Also, right now, the test is done with the middle of the wing fixed, so it doesn't allow for measuring nose flexing. They should use the plank as the fixed part instead, as this would allow the nose to flex in the test without taking suspension travel into account.

[Lindz]

I'm playing devil's advocate a little bit here. It's obviously blatant. But there is no way to control what the wing does when in a dynamic state (short of 'support wires'(more like chastity wires)). You can control every variable you want when the piece is static.

So far, it has complied with all static control tests.

If you simply change those tests to have more weight, I guarantee they will engineer the wing to cope with it. It won't stop 'the problem' (which I see as F1 innovation).

It's also ignorant to think that 'stricter rules' will stop RBR's front wing innovation. Stricter rules affect EVERY TEAM. It will push every team further away from them. What's the weight they test the wings with at the moment? It's not as if Red Bull engineer their wing to withstand [test weight]+1kg and McLaren's wing withstands [test weight]+100kg.

[horse]

Why not? Photographs are admissible evidence in criminal cases, why should F1 refuse such evidence? They are perfectly acceptable evidence if used in the correct way, and reverse engineering a shape from a photograph is not very difficult.

Because it just records a brief moment in time from an unspecified position? The wing has to flex a bit right, if it was totally rigid it would be brittle as well. F1 is a scientific sport and it needs scientific metrics to enforce the rules.

I'm sure some sort of sensor rig (endplates and central section) and a specified mean clearance would do the trick. Altering the current test to multiple points is also a good idea.

[bot6]

The main problem about the test is not the amount of weight, it's where it's placed. The test is a punctual load on the endplate, at a defined distance from the front wheel axis. It's easy to design something that will be stiff in that axis but bend if the load is applied away from that axis.

What I am saying is that the FIA needs a more realistic test relative to aero loads, that tests the wing in more than one point on the endplate to take into account the fact that the aerodynamic center of effort on the wing is something that can change with wing angle.

Saying that stricter rules will just make everyone move away from the rules so we shouldn't bother... Were you a banker specialized in derivatives in another life?

horse -> The problem with sensors on such a highly vibrating thing as a front wing is that they are fairly unreliable and acquisition time makes them useless (especially optical sensors). The only way to stop this thing is to force all teams (not just Red Bull) to make the parts stiff enough, and that can only be done by modifying the bending test.

For the ones who say that if the wing is made stiffer, it will become brittle... That's just a silly excuse. The teams not braking the rules don't seem to be losing their wings.

And for the idea that one picture might just take one specific event... Again, under any circumstances, remember? And all the cars are filmed in the race, so it's pretty easy to check.

[Lindz]

I am talking about a rule that says no aerodynamic device should be designed as an attempt to bridge the gap to the ground (it's the rule that outlawed skirts). And it is forbidden to do so under any circumstances. I believe a running car is a circumstance, right? So it's included under "any circumstances".

The second rule it breaches is the "no part should be under the reference plane" rule. Again under any circumstances.

This is the reason for the RB7's extreme rake. The 'reference plane' is the car's bottom, and it is not horizontal. If the wing appears lower than the front of the tea tray in a picture, it doesn't mean that it breaks the reference plane. On a horizontal plane this would be illegal. With a raked plane, the wing droop may very well still be above it and thus legal.

I'm going to mess with some pictures for a bit and see what I can find (though, again, it is nigh impossible to find side and front pictures of the exact same moment on track).

[Lindz]

Saying that stricter rules will just make everyone move away from the rules so we shouldn't bother... Were you a banker specialized in derivatives in another life?

Haha. Quite the opposite. ... It passes tests. Change the tests, ... or design a better car.

I'm just leaving Honda's advanced design studio in Tokyo. I hear this kind of crap all the time... "Well, BMW is cheating, Honda is an engineering company first so design doesn't take priority."

First of all, they are confusing 'design' with 'styling'. Design is problem solving. Styling is simply moving clay around what lazy engineers give you.

Second of all, if they are stubborn with design because of 'engineering', I don't know what they think BMW is, then... a farming company?