software to be used

[virajshah]

what software should i use to analyze crashes and make a report of the efficiency of the impact attenuator.

[virajshah]

what software should i use to analyze crashes and make a report of the efficiency of the impact attenuator.

[Christopher Catto]

Well, depends totally on what your Uni has since the softwares are complex and sometimes not PC-based. Also, my advice is to avoid doing all the work on your own. Inevitably you may make mistakes and also may find the steep learning curve frustrating. I have little experience of crash software because I only used it as part of academic projects/assignments so here is what little I can say.

From what I remember, you can use one of the following:

Madymo (used by the likes of Nissan). for example if you are comfortable in Rhino (yes, I know it is not strictly a CAD package) then you can save it I think as .sat or something similar. material properties and other inputs are in a text file which is an old fashioned way of doing things. i dont like it at all.

LSDyna (I think part of or can be run with Ansys). matl properties can probably be trasferred from Ansys. Dunno how the newest ansys is but it should import iges quite easily from the likes of Catia, Pro/e, Solidworks, NX3. it did have some problems with I-deas because I-deas translators are a bit tricky to set up regarding iges flavour.

PAM-crash. big program. expensive. never used it. I know F-1 teams use it for their crash simulation before they head up to Cranfield Impact centre or Lola or some other impact centre.

When I did the aluminium crash structure for our car, I just went ahead, built it, then crushed it and applied some formulas to convert quasi-static crushing to dynamic. This is not very accurate and you cant do it anymore for FSAE. So. jut build the thing, in fact maybe if you are laying up, build two (you could always lay up more carbon in the second one if you need), then mount one on an old car that is going to the scrap yard. drive the car with a fixture to keep the accelerator so that the car crashes into a wall. then take a video and measure deformation. of course, you could build a simple drop test rig which is much more professional.

My advice is to build a crash rig. Not so clever (everybody is crazy about simulation) buy you will avoid staring hours into a screen and learn a lot. you can then have data to compare when you actually start doing simulations.

[ben]

If you don't plan on doing a physical test, don't bother with software.

Do a hand calculation, buy some honeycomb, drop a block of concrete on it and measure with an accelerometer.

Ben

[Charlie]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by ben:
If you don't plan on doing a physical test, don't bother with software.

Do a hand calculation, buy some honeycomb, drop a block of concrete on it and measure with an accelerometer.

Ben </div></BLOCKQUOTE>

YES! We have a winner http://fsae.com/groupee_common/emoticons/icon_smile.gif