Impact attenuator testing........again.

[RollingCamel]

After a short discussion with a fellow student participant about the testing, I think that the new rules has just shifted the danger from the street into the university.

"Dynamic testing (sled, pendulum, drop tower, etc.) of the impact attenuator may only be done at a
dedicated test facility. The test facility may be part of the University but must be be supervised by professional staff or University faculty. Teams are not allowed to construct their own dynamic test apparatus. Quasi-static testing may be performed by teams using their universities facilities/equipment, but teams are advised to exercise due care when performing all tests."

The fact is that in countries like ours officials rarely care about safety and only act to save their necks after something terribly goes wrong. I know that this university doesn't have impact testing facilities and the students has agreed with the professors to make the testing equipment by themselves and then the supervisors or professors sign that it is a certified test.

What to do about situations like this?

[,4lex S.]

Run a quasi static test... safer if you are not properly equipped.

[Pete Marsh]

Use the spec impact attenuator.

[RollingCamel]

Quasi-static testing not allowed in FSG. Now there is the standard design, which wasn't available at our time. I don't understand why won't they just use it instead of fraud.

[Stephanie]

My team for the first year purchased the standard attenuator. We are working on attaching it to the anti-intrusion plate. Our thought is to use a high strength glue. But the drawing shows to drill bolt holes. Does anyone have suggestions for attachments?

[spam2128]

Mount it with bolts to the ai plate.
You could epoxy some steel or aluminum to the back of the attenuator, and then bolt it on.
You'll probably want to be able to easily remove it at some point.

[Ahmed_9milli]

The answer is standard impact attenuator, I love this thing.

[Stephanie]

The team wants to eliminate as much hardware as possible and we found a great strong epoxy that will for the foam. What do i submit for the standard ia report? I have my receipt is that all i need? or do I need to include pictures of the epoxy ?

[Rando]

In case of using the standard IA, do we have to submit calculations for the attachment mode? If it's welded, bolded or glued, of the IA/Bulkhead and IA/Intrusion Plate mounting?

On the FSAE IA page (http://www.fsaeonline.com/page.aspx?pageid=193613e4-fff1-4ea9-97ec-eb1c07fbe3c0) FAQ Q2 they are talking about deflection. But in case of using the diagonal brace, we don't have to submit this calculations, isn't it?

[Ben Coburn]

Something I don't understand about the standard design: Why would one want to bolt it to the chassis?

It seems to me that a foam object like this is the last thing that should be attached with bolts. I'd expect that during any sort of not completely head on impact (the only type where the mounting matters) the foam would just fail around the mounting holes, not actually compressing or dissipating much energy at all. Gluing seems much better, not much work with epoxy gives a bond much stronger than the foam itself.

I'm just curious what the reasoning behind the standard design with bolt holes is, because I don't understand it.

[Adambomb]

Originally posted by Ben Coburn:
Something I don't understand about the standard design: Why would one want to bolt it to the chassis?

It seems to me that a foam object like this is the last thing that should be attached with bolts. I'd expect that during any sort of not completely head on impact (the only type where the mounting matters) the foam would just fail around the mounting holes, not actually compressing or dissipating much energy at all. Gluing seems much better, not much work with epoxy gives a bond much stronger than the foam itself.

I'm just curious what the reasoning behind the standard design with bolt holes is, because I don't understand it.

Of course not, that would be silly. Instead, do like others have suggested here and glue it to a plate that bolts to the chassis.

[Ben Coburn]

So given that, does anyone know why the drawings for the standard impact attenuator shows a set of 8 bolt holes?

[spam2128]

Originally posted by Ben Coburn:
So given that, does anyone know why the drawings for the standard impact attenuator shows a set of 8 bolt holes?

Because bolting it on is still an option. If you can remove it, it won't get banged up sitting around in the garage. You're not wasting time grinding down epoxy and waiting for it to dry again if it is ever damaged and needs to be replaced.