Two photos, one question

[asakiyume]

Little Springtime works at the media lab at her university. They have a 3D printer, which, from next semester (... I think?) will be available to students to use. She tested it out and made a hedgehog.



Yesterday and today have been cold, with magnificent if somewhat ominous high winds, but the day before yesterday was warm and melty. Melted snow was coursing down the road. Or rather, it was lapping down the road.

Why does it go down the road in ripples like this? (See the smiles, one after the other? Those are the ripples I'm talking about.) Why not one smooth sheet of water?

Comments

[sovay]

She tested it out and made a hedgehog.

I think that is an excellent test run.

[asakiyume.livejournal.com]

Me too! I never thought I'd have something made by a 3D printer in my house, much less that that thing would be a cute hedgehog.

[dudeshoes.livejournal.com]

I'm crazy about the hedgehog!

[asakiyume.livejournal.com]

He is very cute :-)

[docdad2.livejournal.com]

The water flowing speed is limited by the lower interface and upper free flowing. It builds up a 'Wave" much like you wee at beaches.
Nice use of a 3D printer.

[asakiyume.livejournal.com]

so the friction on the interface causes the water to build up? And that's what makes the wave form?

[docdad2.livejournal.com]

the water exposed to air flows faster than the water against the pavement based on the depth of the water sheet. The wave builds up as a result of the friction between the two flow rates. The wave's weight then speeds up its movement and the speed is maintained by the height of the "Wave".

[asakiyume.livejournal.com]

**thank you**

[greylistening.livejournal.com]

Learning this has made me very happy. Thank you! :)

[genarti]

This is so cool. It never occurred to me that wave physics would apply so visibly to such shallow streams of water. Thank you!

[noachoc.livejournal.com]

What does the hedgehog feel like? Is it rubbery, stiff, papery? Is it solid or hollow?

3D printers blow my mind.

[asakiyume.livejournal.com]

It's solid and very hard and stiff, but very light. Wild.

[oiktirmos.livejournal.com]

Amazing hedgehog!
George Hart (Vi's father) used a 3D printer to make rollers to make Escher cookies. The software is here.
http://www.georgehart.com/rollers/

[yamamanama.livejournal.com]

Vi Hart sounds like the kind of person who would find a way to create a 4D printer so she can have Klein bottles.

[asakiyume.livejournal.com]

I want to make Escher cookies now!

[khiemtran.livejournal.com]

That hedgehog is very cool!

[asakiyume.livejournal.com]

He's quite nice to hold in the hand, too :-)

[scallywag195.livejournal.com]

I was just reading a couple days ago about 3-D printers that are making organs. But....I can't remember much beyond that. I must be getting older.

If we had flowers I'd take pictures and make you ooooo and ahhhhh. What else can I say about the fact that you've gotten our winter? We had pussywillows two weeks ago and a large flock of robins three weeks ago. No snow and only skijored twice all winter.

Hmmmm. Maybe I REALLY should go out and see if the violets have come up yet (even though it's 6 weeks early).

[asakiyume.livejournal.com]

My son was talking about the printer that could print organs! We really are living in the Star Trek future.

The pussywillows are gamely trying to bloom here too. They must be grumbling about the way the season has failed to live up to its side of the bargain--still so cold and snowy!

[scallywag195.livejournal.com]

Have you ever noticed that I'm almost always the last person to comment on your posts?

It's so rare that I actually do anything but emails and maybe write on my computer in the morning and I believe you are several hours ahead of me.

[asakiyume.livejournal.com]

Comments come in waves--a lot depends on posting time, too: is it when the Europeans are up? The American East Coast? The West Coast? India? It really makes me feel the sphericalness of our planet :-)

[danceswithwaves.livejournal.com]

Such a cute little printed hedgehog! Today I learned that the UK is concerned about declining hedgehog populations and is creating conservation spaces for them. Also, there's an entire British Hedgehog Preservation Society!

[asakiyume.livejournal.com]

I'm glad they're under protection! They're sweet creatures.

[heliopausa.livejournal.com]

The Escher cylinder seals are great! Rolled over clay they'd make great plaques, or maybe shallow rectangular dishes to hold fruit.

[asakiyume.livejournal.com]

Yes they would! .... and I'd like to try them for their cookie purpose, too.