Impact Attenuator Test Setup

[Matt K]

Hello All,

I've been working on designing the test setup for our team's impact attenuator this year. So far, what I've come up with is using a forklift with a beam across the forks to lift the load, and having the load attached to the beam through the use of some sort of quick-release mechanism. The only difficulty that I've come up with is that I have been unable to find any sort of quick release mechanism to use for this application...would any other teams who have used similar setups be willing to share what they have used. I am also open to other ideas as well, if you have any. Thanks in advance!

Matt

[Adambomb]

Yep, we ran into this problem too. Haven't done anything about it yet, but...if you're looking for something low-budget, quick and easy, I've heard that a set of bolt cutters can "quickly release" a load suspended by rebar. Also thinking a good set of shears could quickly release a load held with thick poly rope that's $0.65 a foot at Lowes.

[Adambomb]

Or if one were so inclined to use poly rope...IIRC there's some knots that could be used that could serve a quick release function from a safe distance...perhaps something like a shoelace knot. Don't have my Boy Scouts Handbook with me though http://fsae.com/groupee_common/emoticons/icon_wink.gif .

[coastertrav]

Vicegrips...

[Huskie Motorsports TD]

We used a pintle hitch and a 10' length of pipe and hammer to release it from a safe distance. Cut a hole in some 3/4 plate with a healthy draft angle so there is a sharp edge to slide out of the hitch. I know it is a slightly ghetorific set up but for the forklift setup it is pretty good. I would trust this more than the rope, and yes vicegrips are absolutely awesome but come on guys...

[Bazanaius]

Axes have been used to launch trebuchets/catapults for a few hundred years... :-)

[Crispy]

One of our Baja team captains got bored last year and made a pretty simple release mechanism. It worked quite well. I hope the pictures and my crummy paint schematic make sense.

http://lh6.ggpht.com/_a9hR5HUU2fA/S1kgqeKTadI/AAAAAAAAAgU/ECMm8BUjkwM/s400/IAD%20quick%20release.JPG
http://lh3.ggpht.com/_a9hR5HUU2fA/S1lpnapQhnI/AAAAAAAAAhg/eZTqBxHA5Dk/s400/IAD%20quick%20release%20[close%29.JPG
http://lh4.ggpht.com/_a9hR5HUU2fA/S1kgq_hzUhI/AAAAAAAAAgc/R19XA4Cp9is/s400/IAD%20quick%20release%20[inside%29.JPG
http://lh6.ggpht.com/_a9hR5HUU2fA/S1kiFjXix_I/AAAAAAAAAgk/LYhIqVMDFAM/s400/IAD%20quick%20release%20[setup%29.JPG




The inner pieces carry the load and are held closed by the outer square retaining tube. Pull up on the square tube and the load is released. The bearings allowed the retaining tube to move easily. He even included a safety pin to prevent accidental release.

Edit: I suck at pictures.

[Lorenzo Pessa]

http://www.youtube.com/watch?v...MSu0&feature=related (http://www.youtube.com/watch?v=XidX1NQMSu0&feature=related)
here you can find a video of the test we set up last year.
@2:45 you can see the release system. It's pneumatic.

I hope it could be useful to setting up your test.

about the quick release system, if you don't find anything else, you can try to obtain an explosive guillotine.
it is mounted on hoists on SAR helicopter and it's used to cut the cable in case of emergency (with some complaint from the guy at the other end of the cable).
it has to be replace frequently and you can try to ask one (handle with care, at least some grams of high explosive inside) with used cable.

[mech5107]

Similar setup here, with load lifted at the proper height though a rope that we cut using an angle grinder from a safe distance.

[PabloH]

I knew I had seen quick release hooks before, so here is one:
http://www.grainger.com/Graing...e-_-Supplies-_-2YPG2 (http://www.grainger.com/Grainger/items/2YPG2?cm_mmc=Google%20Base-_-Hardware-_-Supplies-_-2YPG2)
But it is $200.

[ibanezplayer]

Our setup was scaled with regards to mass, although I don't believe we will be able to do this, this year. In past years we used a known weight, dropped from a known height, along two guide lines. The weight was then hoisted back up by our old captain, and the next test piece afixed. This also required standing on the roof of a team-mates shop in frigid temps, "after-hours".

[Rellis]

modify a gate latch http://shop1.mailordercentral.com/marshfasteners/images/gatelatch.jpg