I-beam suspension arms.

[Conceptual]

I have been playing around with an idea for a few weeks now, and as soon as I get a bit better in CATIA's Imagine & Shape, I will post some drawings. (tutorial URL's are very welcome!)

My question concerns the A arms of the front suspension. I am interested in knowing if it is possible to replace them both with a single, horizontal piece. I have done enough work to know the layout, and how it would operate and I am in progress on a pic, but I just want to bounce it off the techies here since there are a few different ways to accomplish this.

I see one system as being able to make the entire suspension work through the I Beam, have a downforce generating wing integrated into the design, and a way to make it move ONLY perpindicular to the reference plane, without changing the angle of attack (which was the ONLY concern of other teams concerning McLarens bridge wing in 2007).

I would actually like to get the whole front end with this model that I am working on, but is there any inherent single point failures of using an I-beam in place of the 2 wishbones? Would the loss of the front wing still require an under nose splitter? Any suggestions as to the profile of the integrated aerofoil into the I-beam are welcome, as I have about 300 to choose from.

Any and all constructive, informative, speculative comments are welcome.

[wesley123]

My question concerns the A arms of the front suspension. I am interested in knowing if it is possible to replace them both with a single, horizontal piece. I have done enough work to know the layout, and how it would operate and I am in progress on a pic, but I just want to bounce it off the techies here since there are a few different ways to accomplish this.

I think it is possible, but what do you do to the pushrod(the diagonal arm)?
Ive been thinking about the suspension too and i thought about the same idea, but how can you make it like this while keeping its strength and decreasing the turbulence of it?
I thought about closing the area between, by this the air has to hit the suspension arms like 1 time so it decreases drag. And you can make the pushrod connect to the upper so it will be easier push, this also decreases drag. Maybe there is a way to get rid of the pushrod for all but as far as i know it isnt possible. So i guess closing the area between the wishbones will be more efficient.

[Conceptual]

My question concerns the A arms of the front suspension. I am interested in knowing if it is possible to replace them both with a single, horizontal piece. I have done enough work to know the layout, and how it would operate and I am in progress on a pic, but I just want to bounce it off the techies here since there are a few different ways to accomplish this.

I think it is possible, but what do you do to the pushrod(the diagonal arm)?
Ive been thinking about the suspension too and i thought about the same idea, but how can you make it like this while keeping its strength and decreasing the turbulence of it?
I thought about closing the area between, by this the air has to hit the suspension arms like 1 time so it decreases drag. And you can make the pushrod connect to the upper so it will be easier push, this also decreases drag. Maybe there is a way to get rid of the pushrod for all but as far as i know it isnt possible. So i guess closing the area between the wishbones will be more efficient.

My design uses an integrated paralellogram to keep everything where it needs to be, and I have eliminated the pushrod entirely by using the webbing of the I beam layout.

It is very difficult to describe really, but I am working on a model to explain it.

Does anyone have generative shape tutorials for CATIA? I could probably do most of the generic mock-up in solids, but I would rather the flexibility of planar surfaces.

Thanks!

[wesley123]

My question concerns the A arms of the front suspension. I am interested in knowing if it is possible to replace them both with a single, horizontal piece. I have done enough work to know the layout, and how it would operate and I am in progress on a pic, but I just want to bounce it off the techies here since there are a few different ways to accomplish this.

I think it is possible, but what do you do to the pushrod(the diagonal arm)?
Ive been thinking about the suspension too and i thought about the same idea, but how can you make it like this while keeping its strength and decreasing the turbulence of it?
I thought about closing the area between, by this the air has to hit the suspension arms like 1 time so it decreases drag. And you can make the pushrod connect to the upper so it will be easier push, this also decreases drag. Maybe there is a way to get rid of the pushrod for all but as far as i know it isnt possible. So i guess closing the area between the wishbones will be more efficient.

My design uses an integrated paralellogram to keep everything where it needs to be, and I have eliminated the pushrod entirely by using the webbing of the I beam layout.

It is very difficult to describe really, but I am working on a model to explain it.

Does anyone have generative shape tutorials for CATIA? I could probably do most of the generic mock-up in solids, but I would rather the flexibility of planar surfaces.

Thanks!

I dont really understand it. I will try to make my idea so we can compare.

[bazanaius]

I'd guess the reason is two-fold, but this is only a guess.
Firstly, anti-dive geometry might be difficult to implement
Secondly, you have to transmit the braking and acceleration forces from the contact patch into the chassis. With a wishbone this longtudinal force can be spread along two arms, one in tension and one in compression. With an I-beam this would be an I-beam in bending and I'm not sure you'd get the same stiffness. Either that or your beam would have to be prohibitively large.

I'd still be very interested to see your idea tho - I'm not sure I understand it fully (Im not sure how the front wing comes into it) and a picture would definitely help.

B

[mep]

Actually without any picture I have no idear what you are talking about.
Can you at least make a drawing on a paper and scan it to show us your idear.
Then it should be no problem for someone else to make a CATIA drawing out of it.
If you need help I could make such a CATIA model for you.

[crano]

I'm not sure how you expect this idea will be able to achieve all the same geometry controls of a double wishbone setup. The fact that A-arms have multiple linkages to create a mechanism means you can accurately control caster, camber, static toe, dynamic toe, jacking, etc under different conditions like roll, dive, etc. These all get compromised in design but overall you can design for parameters you need. 1 single I-beam could never achieve anything close to that level of detail. Think about it under brakes. The beam in torsion and bending and somehow expecting to control camber while thats all going on. A beam is also not as an efficient structure as a tube. If you're only doing this for aero efficiency and no other reason I think you'll find your car will have great downforce, but it will be a wallowing sea going yak...

[MrT]

An I beam would not be suitable inplace of an A arm as acceleration and braking forces would put the beam in bending (as a simple cantilever). plus if you are talking about replacing both a arms on a double wishbone layout, with a single pivoted i beam, you are effectivly loosing all camber control and you effectivly have a VERY crude swing arm suspension.

[yzfr7]

replace them both with a single, horizontal piece.

and a way to make it move ONLY perpindicular to the reference plane, without changing the angle of attack

My design uses an integrated paralellogram to keep everything where it needs to be, and I have eliminated the pushrod entirely by using the webbing of the I beam layout.

I really don't understand it.

It is very difficult to describe really, but I am working on a model to explain it.

Yes, hurry. We need to see a picture of your design, because the ideas that you wrote are very conflicting. Structurally it is possible, but you loose all suspension geometry tricks. And just for curiosity, as it is the least of the issues, why are you using specifically an I-beam and not a tube?

[donskar]

?????

Ford used a twin I-beam front suspension on their F150 pickups several years ago.

Please don't go there!

Looking forward to some drawings.

[Carlos]

I remember that twin-I-Beam F150. More advanced than a solid axle, at least the TIBeam was an independent suspension and plus it was Ford Tough But if it's a 'solid' axle, there's at least 8 different ways to stabilize it, including a 'integrated parallelogram ' that is popular with off road vehicles today. Maybe swing axles? Which have horrible camber change, remember the early Corvairs and the original beetle? I think it's a a solid beam axle. There was at least one CANAM Gr7 car that used an interpretation of the beam axle. One very elegant solution came up. Maybe it's a reinvention of the deDion tube axle suspension?

[Conceptual]

Honestly, it came from thinking about simply using the flexibility that the teams integrate into their wings, and how it might be able to replace dampers and A arms in general.

Then, I figured, to do that, you would need to make a VERY modular system, since setting up the car would require changing out the entire piece for different travel needs.

The point was to fuse the front wing into the suspension. Thus getting rid of the front wing, and putting the downforce generation closer to the tyre. After doing some models, and alot more reading, I have come to the realisation that it would be possible, just grossly impractical, since the values for every item would change with usage.

Not only that, but thin nosed F1 cars that have no front wing look absolutely stupid...

I am still working on the task of making the model. I think this project will be named something like F-2020, as a futuristic looking open wheeler. Even if it isn't reasonable today, who knows what materials science may make reasonable next decade?

Thanks for the input, and I promise to post some models as I finish them. I am finding the "Freestyle" workbench in Catia to be pretty comprehensive and intuitive, so it is getting better.

Thanks again!

[bazanaius]

Why not simply make the current wishbone system wider and a lifting device. This is currently prevented under the rules IIRC. Effectively a big wide plate with a hole for the push rod to pass through?

[Conceptual]

Why not simply make the current wishbone system wider and a lifting device. This is currently prevented under the rules IIRC. Effectively a big wide plate with a hole for the push rod to pass through?

This is pretty close to what I was originally thinging about.



Just imagine an endplate on the wing that has an upright mounted to it.

I know that it isn't very feasible, but I still think it would look cool. Especially if combined with these wheels, since most suspension travel is in the rim itself, the rest could be handled by the wing flexibility.


[youtube]http://www.youtube.com/watch?v=ebwofhAT4Ps[/youtube]

Can anyone with better command of a modeling software whip a concept drawing of this up for us? I am sincerely trying, but with 4 kids, time to work uninterrupted is very scarce.

Thanks!

[DSRacing]

From personal experience, an I-beam suspension for a road-based car is a waste. You will have unacceptable camber change and unless you develop an overly complicated steering system, horrendous bumpsteer. The only advantages to the I-beam is strength and simplicty.