3D CAD of chassis and components 1

[TravWood]

Does any body know sources for 3D CAD geometry of car chassis and or components?
Specifically after:
Subaru GC8 ('93-'00) monocoque
Subaru WRX Front and rear crossmember - any year

3D Formats - ideally Inventor assemblies, SAT, IGES etc

I realise I am being optimistic but surely someone has modelled them.

Looking to do some FE on them so I am happy to pass on results to the helpful person who has them.

 

[NickE]

This is a common question.

There is about a snowballs chance in hell of the native CAD data that subaru has getting out. These types of things are very protected. I've worked for a couple of automotive suppliers, we normally recieve blueprints, sometimes even on paper, if we do get CAD data it normally is barely enough to make the part.

nick

 

[TravWood]

Oh Well, I figured this to be the case, just wondering if anyone else has gone to the trouble of either drawing it or 3D scanning any.
I will be getting a quote to scan a crossmember to start with and progress from there.
Thanks NickE

 

[Dave K]

No help with Subaru data, but you can obtain GM, Ford, Chrysler, and Scion data thru the tech transfer program, at SEMA. You have to be a member of SEMA at the manufacturer level.

-Dave
Everything should be designed as simple as possible, but not simpler.

 

[TravWood]

Thanks for the tip Dave, bummer there is no Subaru data there.
Has anybody had much experience with 3D scanning for this sort of end use ie does it generate parts that end up FE friendly?

 

[Ataloss]

I assume by FE you mean Finite Element Analysis? This month's, or maybe last month's issue of Racecar Engineering has an article about using scan data for CFD. They were scanning an entire race car and using that to determine drag, downforce, etc. It should be a good starting point for seeing the amount of work needed to use scanned data for analysis.

I agree with NickE that you won't find the CAD data, though my experiences with receiving CAD data from OEMs are the exact opposite of his. I work for a supplier and for a couple of the OEMs we work with we're actually required to have access to their PLM system and have direct access to all of their CAD data - they will not work with us if we do not do this. I have the entire engine, transmission and chassis front end for several different vehicle programs on my computer. If you are a Tier 1 supplier responsible for the design of your part (that is, the automaker does not design the part and then bid it out to 8 different suppliers) having the CAD data is essential to making sure your part fits in the required space. Am I going to take this data and throw it out onto the Internet for anyone to access? Absolutely not. Not only is it ethically wrong, but if the automaker ever traced that data back to my company, regardless of how unlikely that is, not only would I be out of a job but I bet my company would have quite a few legal issues to deal with. So your chances of finding the CAD data are probably not very good.

This is probably a long shot, but have you tried searching SAE papers to see if Prodrive or one of the other Subaru rally teams did analysis on the parts and published a paper on it? I've had good luck finding info about engines on there (why didn't Ford use the Duratec V6 for their touring car teams instead of the Zetec I4?). You won't be able to run the analysis yourself, but it will help you identify weaknesses in the parts that will need addressing if you decide to race your own car.

Bob

 

[TravWood]

Thanks for the info Bob, no I am certainly not asking anyone to release sensitive information at the risk of any legal/job/ethics reasons. But I guessed a chassis that been out since '93! would not be so sensitive and may be past any time frame for confidentiality.
Yes the scanning would be a good start for CFD work as you are generally just concerned with the outer surfaces, but as I am interested more in the structure, 3D scanning will be a bit more difficult.

Prodrive have released parts but not any information that I have found as yet, will keep an eye out for the sae papers.

 

[Ataloss]

"Has anybody had much experience with 3D scanning for this sort of end use..."

"scanning would be a good start for CFD work as you are generally just concerned with the outer surfaces, but as I am interested more in the structure, 3D scanning will be a bit more difficult."

Are you interested in scanning or not? Before "solid modeling", parts used to be represented in 3D CAD only by their surfaces, and they were used in FEA software just fine. Even solid modeling is really just the computer looking at the surfaces and figuring out what volume is a solid. Whether you use these surfaces for CFD or FEA it's no different - you still need to have a closed volume to use in the analysis.

The process is pretty straightforward: you scan the parts to get a point cloud. You import that point cloud into CAD software. You use the points to create all the surfaces of the part. Trim the surfaces so that there are no gaps between the edges. Sew/join the surfaces togehter. You now have your model. If you want to turn it into a solid, hit the 'solid from surfaces' button. The process is the same whether you want to used CFD or FEA. Does your crossmember have internal ribs that you can't see? Cut it in half and scan the inside!

The article I told you about is all about how to do analysis on things that you don't have CAD data for. It goes into the process of scanning and some of the do's and dont's. These will apply whether you're doing CFD or FEA.