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Water Computing

Posted by michael on from the wetware dept.

Andrew_Cronin writes "This is a nice project that some one did at MIT on building some logic computation systems without using electrons.. So why not use water..."

5 of 303 comments (clear)

  1. Cool...but an old concept by dillon_rinker · · Score: 5, Informative

    Scientific American had an article about water-based logic gates and circuits some decades ago. IIRC, they even created circuits that had no electronic analogy. I can find no reference to this on the web - perhaps some other science geek with access to a complete collection could find it. I believe it was in the Amateur Scientist, but it's been about fifteen years since I read through the stacks of magazines in the cabinets of my chemistry classroom, so I could be mistaken.

    For a similar concept (ie, non-silicon machine logic) that I first read about in the pages of Scientific American, check out the Apraphulians here . For more info on this ancient race, Google is your friend.

  2. Re:But what about...? by Anonymous Coward · · Score: 5, Informative
    how to implement other operation: OR, NOT

    Simple. The author gives XOR and AND gates, formed from joining two streams together, without and without a control. (See the article for details, I haven't taken the time to look into it very deeply).

    Anyways, XOR's function number is 0110. Split it in two, and you get "A(01) when B=0, NOT A(10) when B=1"--two unary gates formed a binary gate. Split AND's function, 0001, and you get "0 when B=0, A when B=1". Trust me, this is easier than it seems. The unary gates are: 00=0, 01=B, 10=NOT B, and 11=1. Now that we got that out of the way:

    • 0 XOR A = A
    • 1 XOR A = NOT A
    • 0 AND A = 0
    • 1 AND A = A

    None of those are useful except 1^A=!A. We need NOT to complete our library of functions too. Now we can combine it with other gates like so using Boolean Algebra:

    NOT(A XOR B) = A XNOR B
    NOT(A AND B) = NOT(A) OR NOT(B)DeMorgan's Law
    NOT(A AND NOT(B)) = NOT(A) OR NOT(NOT(B)) = NOT(A) OR B
    And now, ladies and gentlement, I present to you, The OR Gate:

    not(not(a) and not(b)) = not(not(a)) or not(not(b)) = a or b

    This is constructed from: 1 xor ((1 xor a) and (1 xor b)), and of course the 1 is simply a constant flowing stream of high-power water. And obviously, since NAND is a universal gate, this can be done like so:

    1 xor (a and b) = a nand b
    NAND can make any gate, including NOT, which is then combined as we saw above to form OR, NOR, XOR, XNOR, and even inhibitation and implication if you please.

    Did that answer your question?

    -jc

  3. GEEEZ /. users are morons! by wirelessbuzzers · · Score: 5, Informative

    How can people argue about this for so long!?!? If you really know nothing about chemistry, don't post about it.

    Oxygen is element 8. It has 8 electrons. 6 of them are valence elecrons (in the 2s and 2p orbitals) and 2 of them are "core" electrons in the 1s orbital. Only the valence electrons get drawn in those dot diagrams, that's why you can only see six on some sites.

    Hydrogen is element 1. It has 1 electron. This electron is in the 1s orbital.

    Water is H2O, where the 2 is subscript. It has 2 hydrogens and one oxygen, with polar-covalent bonds between them, so there are 2*1+1*8=10 electrons. Two of them are in oxygen's 1s orbital, four of them are in two of oxygen's four sp3 hybrid orbitals, and four of them are shared between hydrogen's 1s orbital and the other two of oxygen's sp3 hybrids (one orbital and two electrons for each hydrogen).

    Don't even get me started on sp3* anti-bonding pairs.

    Sorry for being inconsistent as to whether numbers should be spelled out.

    --
    I hereby place the above post in the public domain.
  4. Actually in Russia by WetCat · · Score: 5, Informative

    ... water analog computers have been used since 1949... till mid 80-x for modelling differential equations.
    They were used for large-scale projects, such as modelling of water dams.

  5. Fluidic logic has been around for decades by Animats · · Score: 5, Informative
    Fluidic logic has been around since the 1960s. It's often used in industrial process control. It works for both air and liquids. Most industrial systems use air logic, but automatic transmissions often have fluidic logic running on hydraulic fluid.

    The MIT students didn't quite get it right. Their gadget doesn't seem to have gain. The key insight needed for fluidics is that a jet of fluid can be diverted with a smaller jet coming in from the side. This allows building a fluidic amplifier.

    Once you have an amplifier, you can do switches, gates, flip-flops, and other logic elements. Analog control systems, with fluidic sensors and amplifiers driving pneumatic or hydraulic cylinders, are also possible. When the inputs and outputs are pneumatic or hydraulic, it's often convenient if the control system is, too. Fluidic elements are very reliable, too - there are no moving parts except the working fluid.

    One wierd fluidic application is this kosher public address system.