Impact attenuator attachment

[murdock]

Hello,
I am currently dealing with the issue of attaching the IA to the front bulkhead, and I have some questions (serched the forum, still unsure)

1. The rules state a 1.5 mm thickness of the steel made, anti intrusion plate. Is that a minimal requirement, or the thickness allowed?

2. We will be using automotive energy absorbing foam. I am trying to figure out how to attach it to the anti intrusion plate. I thought I should use an adhesive. Is there another recommended method?

thanks

[jordan.k]

1) Minimal
2) Velcro

[moose]

As per the rules "The attachment of the Impact Attenuator must be constructed to provide an adequate load path for
transverse and vertical loads in the event of off-center and off-axis impacts."

Unless you've got some really high-strength velcro that I'm yet to see, I would go a bit more solid.
Depending on how the IA is set up, that could be bolts, epoxy, etc.

[murdock]

Thank you

I don`t understand how to bolt a block of foam to a sheet metal, it seems that would`nt be robust. Than again, i am not experienced in this matter.

Velcro really does seems unsuitable for the attachment, which is a pitty, since it`s so simple to use.

I will set up the test tomorrow. If there is anyone intersted in the setup, do reply.

[Chapo]

3M dual lock velcro, works wonders

[moose]

ok, true, if you get great stuff, it should work. But not your standard crap.

But see the drawings (link on the left of the page)

http://www.fsaeonline.com/Impact_Attenuator.htm

They designed the standard attenuator with 3/8" bolt holes (with 1/2" counterbore) from what I can tell.

[Francis Gagné]

Frequently Asked Questions:
Question 1: Is the mounting scheme shown on the part drawing the only allowable configuration?
Answer: The team should determine the best method of attaching the standard design to their vehicle. The mounting shown on the part print is a suggested method that could be used. Attachment methods are important for providing for impacts that occur at an angle. Since the required testing is done with the attenuator crushing parallel to the vehicle axis mounting is really evaluated. Teams should use good engineering practice and calculations to determine the best mounting method for their vehicle.

From http://www.fsaeonline.com/Impact_Attenuator.htm