Ariel Project

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Discussion

Atom Student

Original Poster:

6 posts

237 months

Friday 17th December 2004
quotequote all
Ladies and Gentlemen,

Hi, my names Chas and Im a third year student doing Mechanical Engineering at Reading University. For my third year project Ariel approached me and asked if I could design them an atom chassis that is as stiff as the current model but lighter (bloody excellent project I know!!!) All is going well and soon I will be presenting my findings to Ariel. However, if any of you, and by the looks of it you have, have any suggestions of things to do, not to do, have done to lighten the chassis then i would be greatful of the details.

Thank you all for your help in this research and don't worry I will reference any points to you in my report.

Kind Regards

Chas

>>> Edited by Atom Student on Friday 17th December 16:03

monza

205 posts

246 months

Friday 17th December 2004
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Cut some lateral tubes which are bad for my elbow
No other intelligent idea for me ...
Good luck,
Jean-Pascal

bruce fielding

2,244 posts

287 months

Friday 17th December 2004
quotequote all
Make it out of something lighter... then offer remortgages for owners.

Sorry - no intelligent suggestions from me either!

ross.mcw

393 posts

262 months

Friday 17th December 2004
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From your stress analysis - are the main chassis rails over strong? My guess is that they perhaps could be reduced in gauge.

Make the floor tub from carbon fibre and incorporate it as a stressed member?

Is there anything gained in adding further panelling, in a trade off for reducing tube gauge?

Can honeycombed Aluminium extrusions be made use of anywhere?


>> Edited by ross.mcw on Friday 17th December 17:55

atom290

1,015 posts

262 months

Friday 17th December 2004
quotequote all
Ross your thoughts are starting to look like a deronda

mullerr

47 posts

238 months

Friday 17th December 2004
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Wouldn't know what the implication would be on strength of the tubing (can't for the life of me remember a thing about finite element analysis), but why not drill 'cheese holes'into the tubing where it is not highly stressed. By 'cheese holes' I'm imagining holes of about half the main tubing diameter at regular (or probably random) intervals along the tubing length.

Atom Student

Original Poster:

6 posts

237 months

Friday 17th December 2004
quotequote all
ross.mcw said:
From your stress analysis - are the main chassis rails over strong? My guess is that they perhaps could be reduced in gauge.

Make the floor tub from carbon fibre and incorporate it as a stressed member?

Is there anything gained in adding further panelling, in a trade off for reducing tube gauge?

Can honeycombed Aluminium extrusions be made use of anywhere?



I can suggest Carbon fibre but there's no way they'll make it for me at the cost!!!

The chassis tubes and panneling are being looked into as possibilities.

Honeycombe aluminium - I think I know where I can use that, thanks.

Monza - due to feed back they asked me if I could get rid of that tube if possible!!!

Thanks guys its appreciated

Chas

Atom Student

Original Poster:

6 posts

237 months

Friday 17th December 2004
quotequote all
mullerr said:
Wouldn't know what the implication would be on strength of the tubing (can't for the life of me remember a thing about finite element analysis), but why not drill 'cheese holes'into the tubing where it is not highly stressed. By 'cheese holes' I'm imagining holes of about half the main tubing diameter at regular (or probably random) intervals along the tubing length.


yeah the strength of the tube is really compromised when you start adding holes in a stressed direction, and a lot of the tubes have possibility of being acted on in many directions especially in a crash, but using it on the non stressed ones is a good idea, thanks

Chas

ross.mcw

393 posts

262 months

Friday 17th December 2004
quotequote all
atom290 said:
Ross your thoughts are starting to look like a deronda

Lol, says the man with a yellow chassised Atom....

ross.mcw

393 posts

262 months

Friday 17th December 2004
quotequote all
Fill the chassis rails with expanding foam. I've no idea what that would do, but that stuff seems to be great for just about anything.

bruce fielding

2,244 posts

287 months

Friday 17th December 2004
quotequote all
They're not chassis-related , but here are a couple of ideas to save weight

1. You could get rid of the plastic around the front and rear suspensions that makes getting the wheels up on a jack so tricky. Probably save a few grammes and several centimetres of finger skin! Doesn't seem to add much in terms of aerodynamics or occupant element protection.

2. Make the second seat detachable so you can run it solo.

3. Do the indicators and sidelights have to be on separate stalks? Could they be incorporated into the black plastic either side of the nose and into the tea tray at the back?


Plus I just thought...

Do there have to be two members going down the middle on the floor? Would one be strong enough?

G Man

4,053 posts

265 months

Friday 17th December 2004
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Atom Student

T45 steel ....

G MAN

ross.mcw

393 posts

262 months

Friday 17th December 2004
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Transparent Aluminium - it worked for Scotty....

Bruce Fielding

2,244 posts

287 months

Friday 17th December 2004
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My old bicycle was very proud of having Reynolds 531 tubing (whatever that is...)

>> Edited by Bruce Fielding on Friday 17th December 23:03

atom290

1,015 posts

262 months

Saturday 18th December 2004
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G Man said:
Atom Student

T45 steel ....

G MAN


That’s what I used for the roll cage.....its great stuff!

I don’t know what the difference would be in gauge size between steel and aluminium tubes? Obviously you going to have to up the size, but would that make a weight saving?

I can’t really talk as mine is actually heavier!

But I added structure to mine, as I felt it needed some extra rigidity in certain places, especially with the extra power.

I did remove some of the side bars so that i didn’t knock my elbows....unfortunately i did have to extra ones.....so that doesn’t really help on the weight saving.

I think you could look at making the chassis stiffer?

Jay Ar

2 posts

239 months

Saturday 18th December 2004
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1. I've always been surprised by the diameter and gauge of the two main side rails, why not do something mad like take one out and put it underneath as a central member (good for cost), or have three very much smaller main rails at the side (could be good for weight optimisation but not sure for cost).
2. Except of course going for some exotic grades of steel (Aluminium is out in my opinion - too expensive for the same rigidity and in any case in the end you'd have the same weight as the steel alternative) why not copy the old & new F1 cars chassis design? I imagine you're a bit limited to radically change the "look" of the chassis (an Atom trademark), but how about using the engine as a structural member (need to be careful as road car engine aren't designed from scratch as being structural)? You could then hang the rear suspension off the engine and gearbox.
3. It's all a bit difficult giving you ideas (I doubt we'll come up with anything groundbreaking, otherwise we'd be working for a racing team!!), but I'm sure we could help more if we could see the results of your finite element analysis. Would it be possible to post some images on the forum of a couple of critical load cases? Or even better (for me at least) send me the data - I work for the company that develops Catia and have plenty of colleagues who could help me analyse your load cases (CAD data or even better nastran data would be cool).

Atom Student

Original Poster:

6 posts

237 months

Sunday 19th December 2004
quotequote all
Thanks for the suggestions people shall look into the ones I haven't already.

Jay Ar - Soz but Im bound by a confidentiality contract that I had to sign before starting the project agreeing not to give out any data of that kind. And your right about the shape of the chassis, its a unique shape that you associate with the atom and they dont want it radically changed.

Thanks

Chas

greenphotos

33 posts

237 months

Monday 20th December 2004
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Hiya Chas,

As you probably know, I know next to nothing about the different properties of metals, but here is one idea:
Could you make the tubes a little thinner? Shaving a few millimeters off the diameter all over, once all added up should save quite a bit of weight?

Hope all is well,

Mark

atom290

1,015 posts

262 months

Monday 20th December 2004
quotequote all
There is a major compromise between weight and safety, knowing my ability to sometimes try the more adventerous approach and drive on the green stuff, i want every possible protection.

Yes you can look at things not going wrong, but youd rather go into battle wearing armour than a fig leaf?

LongQ

13,864 posts

238 months

Monday 20th December 2004
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There's a guy called Mike Keenan who seems to have invented a fire proof (or at least very very very highly resistant) coating for any material.

He also has a way of creating some extemely light 'plastic' material, including the fire proof component, which is apparently harder and stronger than steel. It's made from household waste and apparently costs very little to manufacture.

I have held a piece of this stuff, about the thickness of a UPC barge board for a house, and it was indeed very very light. A gas blow torch (about 1000 degrees apparently) played on one side of it for several minutes, singed the surface but did no more than that. I was holding the sample on the palm of my hand. There was almost no heat transfer through the material - 2 or 3 degrees max I would say and that only after the torch was removed or I just did not notice it at the time. The singed surface was cool to touch within 15 seconds - very slight residual warmth.

One of the thoughts I had at the time was that there had to be a use for this material in sports automotive design. Clip on side panels for an Atom for example. Perhaps more, depending on what can be done with the material to shape, mould, mill or otherwise machine it during manufacture and assuming it doesn't have serious tensile problems in certain planes.

I have some photos of a fire resistant grease demo and I think I can get some of the material demonstration as well if anyone is interested.