
Programmable Water - llambda
http://www.blikstein.com/paulo/projects/project_water.html
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jonsen
The air version, Pneumatic logic:

[http://en.wikipedia.org/wiki/Pneumatics#Pneumatic_logic](http://en.wikipedia.org/wiki/Pneumatics#Pneumatic_logic)

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andrewcooke
it's taken me a good 5 minutes to convince myself a single device can be both
AND and XOR. that's weird stuff.

is there any way to get AND, XOR and NOR in a single device "for free"? after
all, they don't overlap (only one is 1 for any given pair of inputs).

also, how do you build a practical system when the flow rate is not constant
(AND doubles the flow here, for example)?

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jonsen
_a single device can be both AND and XOR. that 's weird stuff._

I'd say it depends on how you would define "single device". Imagine the
possible complexity of such water devices build with a 3D printer and still
it's just a lump of uniform material, albeit structured.

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gizmo686
I think that a distinction can be made here. Consider the device as an XOR
gate. There is no element within the device that is not a fundamental part of
the XOR system. The AND gate arises as a natural result of constructing the
XOR gate. This feels fundamentally different from constructing an XOR gate,
and then adding an AND gate.

On a meta-level, in writing the above comment, I feel as if we are missing
some critical vocabulary that would make this entire question seem trivial.
Any ideas on what this vocab. is?

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TeMPOraL
I guess this adds a whole new meaning to the phrase "bit bucket" :).

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AlwaysBCoding
bro, do you even CSS?

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csense
How does this story get 56 points and frontpage (as of this writing), yet when
I submitted an article on computing with water droplets on superhydrophobic
surfaces [1], it didn't get any upvotes at all?

Anyone have ideas for reducing the tendency of HN to sometimes ignore high-
quality content? I shudder to think about how stressful being ignored must be
for startups who try to launch their product or get feedback here...

EDIT: Multiple downvotes? Does this mean that people are uncomfortable with
the idea that HN may be less than perfect? Or is it merely because my
comment's too far off-topic?

[1]
[https://news.ycombinator.com/item?id=4885419](https://news.ycombinator.com/item?id=4885419)

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GuiA
Don't take it personally dude. It's a human system, therefore an inherently
flawed one.

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csense
I'm not taking it personally. I'm trying to ask all the clever people here to
put their hacking hats on, and think up an analysis of this particular flaw,
or ideas for technological ways to mitigate this problem.

I _am_ a little bitter about the situation, I suppose, and maybe this leaked
into my comment. My intention was to set the tone of a matter between adult
professionals: "Here's a problem I experienced. Let's try to solve it." Maybe
I didn't entirely succeed in setting that tone.

~~~
frogpelt
This is a problem that won't be solved with an algorithm. Emotions dictate the
actions of humans. It's hard to fix that problem.

You sound like someone who checks your watch to figure out whether you're
hungry or not.

