Egg Drop ideas?

[David Knaack]

Anybody want to discuss their egg drop technique?

Or maybe feed us some convincing but ultimately bad advice in an effort to gain a competitive advantage?

[Kevin Fusselman]

I sorta like the way egg cartons work... They rely on force distribution...  Maybe you could take a great-stuff mold of an egg, and split it in half...

[Stephanie Jensen]

Use of anvil. Just sayin'.

On Fri, Mar 9, 2012 at 2:38 PM, David Knaack <david...@gmail.com> wrote:

[Benjamin Hutcheson]

I've been thinking along the lines of slowing the fall, considering how large a drop we're considering.  I had originally discarded the possibility of just using cushioning, but in retrospect, 15 inches allows for a LOT of cushioning.  I'm not positive Great Stuff would be my first choice (too stiff, I fear) but this is Dave we're replying to. . .

-Ben

[Eric J. Kaplan]

Aerogel....

Sent from Eric's iPhone

[Kevin Fusselman]

@Ben: You've grasped my point exactly. 

[David Knaack]

Any strategy can be considered from the perspective of reducing the shock pulse to a survivable level. This can done by expanding the pulse time to reduce the amplitude (pulse energy is distributed in time), and also by reducing the amount of energy contained in the pulse (slowing the fall prior to impact). It's also important to consider how the energy is transferred to the target object.

Cushioning is a method of distributed the pulse in time, and also of spreading the force across the surface of the egg. Maximizing wind resistance (such as with a parachute) would reduce the total energy that must be spread about.

I like the foam mold idea because it distributes impact force from any direction evenly across a relatively large proportion of the surface of the egg. Depending on the rigidity of the foam, it also provides some cushioning.

An added consideration is rebound. Since we're trying to hit a target, a package that is 'dead' is good, so it doesn't bounce or roll away from the landing zone.

On Fri, Mar 9, 2012 at 2:45 PM, Kevin Fusselman <ke...@fusselman.org> wrote:

[Kevin Fusselman]

To your last point, entries are judged, as you say, the location where the device STOPS, not where it first makes impact. (I was previously confused on this particular point).

[Eric J. Kaplan]

How about an array of sacrificial eggs to take the blow?  >;-[

Sent from Eric's iPhone

[Kevin Fusselman]

Perhaps if you could.. erm... liquidate the fluid inside somehow... Eggs are heavy.

[David Knaack]

Not bad. The rules don't say you have to drop only one egg, or that one specific egg must be pre-designated as the payload. As long as one makes it, you're good.

They're probably a little heavy though.

On Fri, Mar 9, 2012 at 3:16 PM, Eric J. Kaplan <ekap...@gmail.com> wrote:

[David Knaack]

Along that same line of thinking, you could decalcify the shell so it would be less likely to crack.

On Fri, Mar 9, 2012 at 3:16 PM, Eric J. Kaplan <ekap...@gmail.com> wrote:

[Stephanie Jensen]

Had been thinking of inserting the egg in a nerf ball - but yes, given this interpretatino of the rules, rollaway is a consideration.....

[Travis Smith]

I'd be more interested in seeing an anti contest:  how far can your egg splatter from the impact site?

Travis

[Kevin Fusselman]

That could be sorta like the "shoot the moon" prize :)

[The_IndustrialPhreak]

three words. ESTAS model rockets

On Mar 9, 10:32 pm, Kevin Fusselman <ke...@fusselman.org> wrote:
> That could be sorta like the "shoot the moon" prize :)
>
>
>
> On Fri, Mar 9, 2012 at 8:00 PM, Travis Smith <travi...@gmail.com> wrote:
> > I'd be more interested in seeing an anti contest:  how far can your egg
> > splatter from the impact site?
>
> > Travis
>

> > On Fri, Mar 9, 2012 at 5:51 PM, Stephanie Jensen <sjense...@gmail.com>wrote:
>
> >> Had been thinking of inserting the egg in a nerf ball - but yes, given
> >> this interpretatino of the rules, rollaway is a consideration.....
>
> >> On Fri, Mar 9, 2012 at 3:05 PM, Kevin Fusselman <ke...@fusselman.org>wrote:
>
> >>> To your last point, entries are judged, as you say, the location where
> >>> the device STOPS, not where it first makes impact. (I was previously
> >>> confused on this particular point).
>

> >>> On Fri, Mar 9, 2012 at 3:01 PM, David Knaack <davidkna...@gmail.com>wrote:
>
> >>>> Any strategy can be considered from the perspective of reducing the
> >>>> shock pulse to a survivable level. This can done by expanding the pulse
> >>>> time to reduce the amplitude (pulse energy is distributed in time), and
> >>>> also by reducing the amount of energy contained in the pulse (slowing the
> >>>> fall prior to impact). It's also important to consider how the energy is
> >>>> transferred to the target object.
>
> >>>> Cushioning is a method of distributed the pulse in time, and also of
> >>>> spreading the force across the surface of the egg. Maximizing wind
> >>>> resistance (such as with a parachute) would reduce the total energy that
> >>>> must be spread about.
>
> >>>> I like the foam mold idea because it distributes impact force from any
> >>>> direction evenly across a relatively large proportion of the surface of the
> >>>> egg. Depending on the rigidity of the foam, it also provides some
> >>>> cushioning.
>
> >>>> An added consideration is rebound. Since we're trying to hit a target,
> >>>> a package that is 'dead' is good, so it doesn't bounce or roll away from
> >>>> the landing zone.
>
> >>>>  On Fri, Mar 9, 2012 at 2:45 PM, Kevin Fusselman <ke...@fusselman.org>wrote:
>
> >>>>> I sorta like the way egg cartons work... They rely on force
> >>>>> distribution...  Maybe you could take a great-stuff mold of an egg, and
> >>>>> split it in half...
>

[Eric J. Kaplan]

So... Serious question from me:

- is the geometric restriction going to be measured before or after the drop? And does our device have to maintain that geometric size during the drop?

A parachute can start small and get pretty big....

Sent from Eric's iPhone

[David Knaack]

I would think that it only makes sense to measure the 'as dropped/launched'.

And speaking of the drop, what's the plan for that?

[Eric J. Kaplan]

I did go back and look at the rules and it says that the measurements are taken _before_ the drop. 

Sent from my iPad

[Brandon Norris]

" If the device has wings or a parachute, the longest length will be measured with the

wings or parachute fully expanded."

from the rules we are copying.

[Kevin Fusselman]

For the drop itself, I was going to look around the Makery tonight to see how high we can get.  Hopefully, height can exceed 10 feet...

[Brandon Norris]

We could do it off the wall outside the garage door. as long as the weather isnt bad.

[Kevin Fusselman]

That's a good idea.  

IRC, that wall is about 7 feet tall, plus the height of a person on top of it.  Sadly, the driveway is too wide to use the depth of the loading dock too...

[Travis Smith]

Can't you guys figure out a way onto the roof?

Travis

[David Knaack]

There is a door onto the roof, but it's probably a bit late to get access and permission.

Maybe we can put a cable-release hook on the end of a pole and attach the packages to that to gain another 5-10 feet above the wall.

[Eric Kaplan]

Access? Permission? What are these concepts of what you speak???

--

Eric J. Kaplan                                       

• ekap...@gmail.com
• www.ejk00.smugmug.com

[Kevin Fusselman]

Something to consider (that I just came across): The maximum edge length of a cube to maintain the 15" sphere requirement is just 8.66 inches.

http://www.wolframalpha.com/input/?i=side+length+of+a+cube+with+a+diagonal+of+15+inches 

[Eric Kaplan]

Do we have a 15" diameter sphere to use as a measuring device? 

[Kevin Fusselman]

I don't think so... That'd be difficult to use, in any case...