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A Lego Replica of the Antikythera Mechanism

vbraga writes "The Antikythera Mechanism is the oldest known scientific computer, built in Greece at around 100 BCE. Lost for 2000 years, it was recovered from a shipwreck in 1901. But not until a century later was its purpose understood: an astronomical clock that determines the positions of celestial bodies with extraordinary precision. In 2010, a fully-functional replica out of Lego (YouTube video) was built."

51 of 74 comments (clear)

  1. I must have this!! by erroneus · · Score: 3, Interesting

    I need a parts list and build instructions. Anyone know if they did this? All we got was a Youtube video...

    1. Re:I must have this!! by Fallen+Kell · · Score: 1

      That was the first thing I thought as well.... Want to build one myself!

      --
      We were all warned a long time ago that MS products sucked, remember the Magic 8 Ball said, "Outlook not so good"
    2. Re:I must have this!! by JaZz0r · · Score: 5, Informative

      Andrew Carol is the designer. His website has more information - http://acarol.woz.org/antikythera_mechanism.html If the site is down, try the Google cache

      --
      "Careful! We don't want to learn from this!" -Calvin & Hobbes
    3. Re:I must have this!! by TheMidget · · Score: 5, Informative
      .... which also shows that it is not a replica of the Antikhera mechanism. It achieves the same purpose (predicting eclipses), but using a different mechanism, because they needed to work with gear ratios achievable with available Lego pieces, and thus needed to add differentials, whereas the Greeks had no such needs (making their own gears, so being able to directly use whatever ratio was needed). Moreover, display differences (4-wind spirals versus 5) introduced more differences in the multiplicative constants, and thus the mechanism:

      Because it would be difficult to fit the information for 223 lunar months in a single rotation of a dial, the original machine used a 5 wind spiral to encode the information. This made more space available for the markings required for the eclipse information.

      My version of the machine uses a 4 wind spiral. This provides the same benefit as a 5 wind spiral but matches the Full Moon Cycle which may permit future enhancements to accuracy.

      This change results in the formula:

      Saros4 = Y * 4 * 235 / (223 * 19)

      I decided to not use the Corinthian calendar and instead use the standard Gregorian civil calendar in a four wind spiral representing the four year leap year cycle.

      Noting that 235 is 5 * 47 and 254 is 2 * 127, the important constants for the construction are:

      4, 5, 19, 47, 127, and 223.

      The readily available high quality LEGO gear ratios are combinations of 1, 3, and 5. With some challenge 4 is available. With these combinations we can get to gear ratios which are multiplicative combinations of these values. The easy ratios we can get to include: 1, 3, 4, 5, 9, 12, 15, 20, 25, 27, etc.

      Ratios of 19, 47, 127, and 223 are impossible to achieve with simple gear ratios because they are prime numbers. We have to look beyond simple gears to differentials.

    4. Re:I must have this!! by AmberBlackCat · · Score: 3, Insightful

      It would be nice if I walked into a toy store and saw a Lego set with this on the front of the box instead of a Star Wars ship.

    5. Re:I must have this!! by Tablizer · · Score: 3, Insightful

      It would be nice if I walked into a toy store and saw a Lego set with this on the front of the box instead of a Star Wars ship.

      It doesn't have to be mutually-exclusive: A Millenium Falcon can be made to predict eclipses. Of course you need a Wookiee to bang on it when it jams.

  2. Comment removed by account_deleted · · Score: 1

    Comment removed based on user account deletion

  3. See "The Making of" too by wiredlogic · · Score: 4, Interesting

    Not to be missed is the time lapse video of the process of creating the video which was as fascinating as the model itself.

    --
    I am becoming gerund, destroyer of verbs.
  4. As opposed to by Aerynvala · · Score: 1

    non-scientific computers? So is there an even earlier computer that was in some way un-scientific?

    --
    http://transformativeworks.org/
    1. Re:As opposed to by Tumbleweed · · Score: 1

      non-scientific computers? So is there an even earlier computer that was in some way un-scientific?

      Sure. The one in the human head.

    2. Re:As opposed to by noidentity · · Score: 1

      The computers they built to play Farmville were probably unscientific.

    3. Re:As opposed to by AHuxley · · Score: 3, Interesting

      http://en.wikipedia.org/wiki/Berlin_Gold_Hat ~ bronze age pda (personal duration assistant?) meets lunisolar calendar meets bling sun cult headdress?

      --
      Domestic spying is now "Benign Information Gathering"
    4. Re:As opposed to by Aerynvala · · Score: 1

      that's quite neat!

      --
      http://transformativeworks.org/
  5. my scientific observation by Tumbleweed · · Score: 4, Interesting

    "A device is not truly understood until its function can be duplicated by Legos."
    - Tumbleweed's Observation

    1. Re:my scientific observation by jcr · · Score: 2, Funny

      I think I understand how an oxy-acetylene torch works, but I don't think I could duplicate its function with legos...

      -jcr

      --
      The only title of honor that a tyrant can grant is "Enemy of the State."
    2. Re:my scientific observation by Anonymous Coward · · Score: 2, Funny

      I think I understand how an oxy-acetylene torch works, but I don't think I could duplicate its function with legos...

      Well, you can duplicate its function with bacon. That also counts.

    3. Re:my scientific observation by jbeaupre · · Score: 1

      There is a pneumatic set. I don't recommend it, but you could build an oxy-acetylene torch using the pressure vessel, tubes, connectors, and valves.

      --
      The world is made by those who show up for the job.
    4. Re:my scientific observation by Xyrus · · Score: 1

      "A device that cannot be replicated by legos is not worth understanding."

      --
      ~X~
    5. Re:my scientific observation by Tumbleweed · · Score: 1

      "A device that cannot be replicated by legos is not worth understanding."

      Excellent. And now I think we can get a nice research grant.

  6. Re:2 Months old by noidentity · · Score: 1

    This is the second run in case you missed it the first time two months ago.

  7. Re:So... by neokushan · · Score: 4, Funny

    No, you idiot, that's obviously not how it works. If you find a bug in this, you cause the entire celestial system to collapse in on itself, killing us all!

    --
    +1 IDisagreeSoHeMustBeATrollOrAnAstroturferOrAShill
  8. More Information by breser · · Score: 3, Interesting

    Built by Andrew Carol who is an engineer for Apple.
    He had a website about his building complex lego machines at: http://acarol.woz.org/
    And specifically information about this one at: http://acarol.woz.org/antikythera_mechanism.html

    Unfortunately, the site seems to be down but Google still has a good cache:
    http://google.com/search?q=cache:acarol.woz.org/antikythera_mechanism.html
    http://google.com/search?q=cache:acarol.woz.org/acarol.woz.org

    1. Re:More Information by intellitech · · Score: 1

      Unfortunately, the site seems to be down but Google still has a good cache

      Ahh, yes. The slashdot front page effect. Funny how that works.

      --
      vos nescitis quicquam, nec cogitatis quia expedit nobis ut unus moriatur homo pro populo et non tota gens pereat.
    2. Re:More Information by madmayr · · Score: 2

      Ahh, yes. The slashdot front page effect. Funny how that works.

      maybe we should build a slashdot-effect-machine out of LEGO

    3. Re:More Information by Tablizer · · Score: 1

      Built by Andrew Carol who is an engineer for Apple.

      Steve Jobs is going to purchase Lego Inc. and shorten the name to Ego.

    4. Re:More Information by AngryDill · · Score: 1

      No, he'll probably replace the "L" with an "i"... giving the world the iEgo.

      -a.d.-

      --


      I'm Erwin Schrodinger and I approve of this message, and I do not approve of this message!
  9. Antikythera Reconstruction ? by Anonymous Coward · · Score: 3, Interesting

    This has as much to do with the Antikythera mechanism as a software simulation. The mechanism has no differential gears, which are used on this lego construct because its creator played with them during his experiments with Babbage's Difference Engine. The beauty of the Antikythera machine lies in its pin-and-slot mechanism for modelling epicyclic trajectories which are of course nowhere to be found in this "reconstruction".

    1. Re:Antikythera Reconstruction ? by TheMidget · · Score: 1

      This has as much to do with the Antikythera mechanism as a software simulation. The mechanism has no differential gears, which are used on this lego construct because its creator played with them during his experiments with Babbage's Difference Engine.

      Nope, the main reason for using differential gears is that with normal Lego gear pieces only certain ratios are achievable... which unfortunately do not include those needed by the Antikythera mechanism. So they had to obtain those by averaging two obtainable rations. And, in order to perform this "averaging" you need differential gears.

      So this is a mechanism achieving the same purpose as Antikythera, but implemented using a completely different way due to different constraints.

      See Building complex machines using lego pieces, and then scroll to "The Practical Considerations" (hey, never heard of an <a name=""> tag?)

  10. NOT a replica by Gravis+Zero · · Score: 2, Informative

    it's an implementation of the same math that that the Antikythera mechanism does but it's done in a completely different fashion.

    Woz explains the device on his own page as well as the math behind it: http://acarol.woz.org/antikythera_mechanism.html
    There is also an article about his LEGO device: http://www.fastcodesign.com/1662831/how-one-engineer-redesigned-an-ancient-greek-mechanical-computer-out-of-legos

    more information about the Antikythera mechanism can be found here: http://en.wikipedia.org/wiki/Antikythera_mechanism

    --
    Anons need not reply. Questions end with a question mark.
    1. Re:NOT a replica by thestuckmud · · Score: 1
      It implements some of the same math, but misses some features of the original. For example, I don't see the pin and slot drive used to approximate the varying angular velocity of the moon due to its elliptic orbit. Nor the spherical phase of the moon display on the front dial.

      More importantly, we can only speculate about features that have been lost to history. Estimates of the gear count range from 30 to 70. No one today known for sure.

      Still, it is an impressive bit of lego work!

    2. Re:NOT a replica by mikael · · Score: 1

      HP Labs managed to recover the instruction manual that was written on the side of the machine, so the archaeologists are more or
      less certain they know the purpose of each internal gear, as well as the dials and indicators.

      High resolution image

      Fascinating to know that someone was designing interactive user interface 2000 years ago...

      --
      Vintage computer adverts: http://www.vintageadbrowser.com/computers-and-software-ads
    3. Re:NOT a replica by thestuckmud · · Score: 1

      See the most recent Antikythera mechanism paper [Nature V468 P496, 25 Nov 2010] for proof that our knowledge of the mechanism is incomplete. For example: "Evans’s hypothesis forces a rethink of other parts of the mechanism, too. Previously, scholars assumed that the positions of the Sun, Moon and planets were all displayed around the same zodiac scale. But if the zodiac scale had been tweaked to accommodate the varying speed of the Sun, it would no longer be accurate for showing the positions of the other bodies."

      Note that the gearing for any planet display is missing from the fragments of the mechanism. Even if we had instructions about these presumed dials (which we do not), the actual gearing is still a matter of speculation, not certainty.

    4. Re:NOT a replica by loshwomp · · Score: 1

      HP Labs managed to recover the instruction manual that was written on the side of the machine

      I didn't see a translation anywhere, but I'm pretty sure it says "replace toner cartridge now".

  11. As opposed to abacus by mangu · · Score: 2

    is there an even earlier computer that was in some way un-scientific?

    Certainly, the abacus is much older and was used for business, as opposed to scientific, calculations.

    1. Re:As opposed to abacus by Aerynvala · · Score: 1

      I didn't realize the abacus could be defined as a computer. A calculator, sure.

      --
      http://transformativeworks.org/
    2. Re:As opposed to abacus by hitmark · · Score: 1

      The distinction between the two is artificial at best.

      --
      comment first, facts later. http://chem.tufts.edu/AnswersInScience/RelativityofWrong.htm
    3. Re:As opposed to abacus by coolmadsi · · Score: 1

      The distinction between the two is artificial at best.

      Indeed. I think the term 'computer' originally meant "someone who computes" and there were rooms of people doing mathmatical calculations.

    4. Re:As opposed to abacus by hitmark · · Score: 1

      Yep, some of the ww2 code cracking was done that way. Office after office with ladies doing sheet after sheet of calculations by hand (or aided by mechanical calculators).

      --
      comment first, facts later. http://chem.tufts.edu/AnswersInScience/RelativityofWrong.htm
  12. Anti-kythera? by Chemisor · · Score: 1

    So what's this "kythera" that they were so afraid of? Is it coming?

    1. Re:Anti-kythera? by Pyrus.mg · · Score: 1

      C'thulu's ex-wife.

  13. Really impressive by RNLockwood · · Score: 1

    It's really an accomplishment to have been able to piece out the internal structure of the badly corroded artifact and deduce its function and how it worked. It's also remarkable to have built one out of Legos. What a coincidence that the dimensions of the Lego parts were very close to the same dimensions of the parts in the artifact; if not the Lego machine would be a working model, not a replica.

    --
    Nate
  14. Re:So... by The+Grim+Reefer2 · · Score: 1

    If I find a bug in this, I can hack any computer ever released in History?

    No, it means you need to use these in your parents basement.

  15. Re:Ahh LEGO... by rossdee · · Score: 1

    I think high loads in general would be out. I don't think it would be possible for instance to have a full size model of the golden gate bridge and expect it to stay up.

    If you tried to make a solid sphere a light year across out of legos I think it would collapse into a black hole. (And the galaxies financial system would collapse trying to pay for it.)

  16. Double the gears? by Tablizer · · Score: 1

    A quick blurb says it uses twice as many gears as the original, perhaps because they had to use off-the-shelf teeth counts. I'd like to see a reconstruction of the original, not a reconstruction of the function.

  17. Re:BCE? by jfengel · · Score: 1

    The term BCE has been used since the 19th century. It predates everybody here, and it also predates the term "politically correct".

  18. Re:BCE? by RightSaidFred99 · · Score: 1

    It's also laughably silly. I'm atheist, but seriously - giving a date based on some event a new name does not change the significance of the date. It's childishness.

  19. Re:2 Months old by gstrickler · · Score: 1

    To the idiot who moderated this offtopic, try again. The comment is exactly on topic.

    --
    make imaginary.friends COUNT=100 VISIBLE=false
  20. Re:BCE? by gnapster · · Score: 1

    And yet BCE, in turn, is predated by "BC," by at least a thousand years.

  21. Arthur C. Clarke said about the Antikythera by purplemecha · · Score: 1

    Arthur C. Clarke on the TV show "Mysterious World" said if the Antikythera Mechanism had not been lost, we might have populated all the stars visible to the naked eye. What he meant was that the lost of the Antikythera Mechanism set back computing by 2000 years. He reasoned that if it had not been lost, that we might have been 2000 years farther along in computing. It really does boggle my mind to think what could have been if this had become widely known and used, would we have really gone to the stars by this time.

    1. Re:Arthur C. Clarke said about the Antikythera by jarlsberg71 · · Score: 1

      Steampunk would have really rocked the industrial age a few hundred years earlier.

      --
      E8B8B
  22. Re:Obvious next step by Coren22 · · Score: 1

    Are there gears in Minecraft now?

    --
    APK likes to ask for responses to the same things over and over. Maybe he just likes the responses?