Asymmetric Gear Heart Sculpture


Here’s a video of a mindbending piece of papercraft engineering. We’d love to see a 3D model for this heart to at least have a starting point when designing our own. The creator’s site is in Japanese though, so it’s hard to glean any insight into his process. Embedded below is a similar cube version.[youtube=]

[via Waxy]

33 thoughts on “Asymmetric Gear Heart Sculpture

  1. Wow. I’m still having trouble wrapping my brain around this. In both the heart and cube version there is only one gear that rotates about a single axis, and it’s at the base of the object. How are the rest of the parts held in place?

    Leave it to the Japanese to create something so impressive out of paper, which aside from it’s artistic value is essentially worthless.

  2. i bet the pieces are held in with a flexible axle maybe made from a spring or something so they cant fall out but can still move around somewhat… my god though. they must have made this with cad or something and printed out on card stock or something?????????

  3. @amk
    in the heart, there is a vertical axle and (i think) four horizontal axles: two intersect above the bottom gear (e.g. x,y,z axis) and the other pair is below the top gear in the same fashion. the “illusion” is a product of the width of the individual gears.

  4. Pretty cool… At first it seems like the gears are asymmetrical, but they are actually just cone shaped, bevel gears meshed to fill a volume, then their outer ends are shaped to form the heart or cube. Once you set up the group of gears, you could probable carve it to any shape you wished.
    The bottom gear is probable freely turning on a hollow shaft, with a central axle driving the top gear which in turn, drives all the others. Like the bottom gear, the other driven gears are mounted to the fixed hollow shaft.
    Take a look at ‘bevel gears’ on wikipedia, and you should be able to figure out how it’s done from the diagrams.

  5. Reminds me of Arthur C. Clarke’s famous quotation, “Any sufficiently advanced technology is indistinguishable from magic.” But this is more like sorcery than magic!

    @pip: does something require electricity to be a “hack”? “Hack: n, A clever or elegant technical accomplishment, especially one with a playful or prankish bent.” (Urban Dictionary)

  6. actually… the gears ARE asymmetrical…. look at the heart before he starts turning it. There is a big gear on the right side, but a small gear on the left…. the opposing gears aren’t congruent.

    All I have to say is:

    OMG! That thing rocks! It was so cool I actually posted a myspace bulletin with the embedded video in it.

  7. I already posted this on YouTube, but to anyone interested in making one of these, maybe my translation will help? I loved this too much to just leave others in mystery. Sorry it’s a bit long..

    “これは歯車のハートです (This is a heart of gears). この作品は,これやこれのように,十五の歯ついた歯車が三つ(This object has 3 gears with 15 teeth, like this and this).これやこれやこれやこれのように十の歯がついた歯車が九つ (It has nine gears with 10 teeth, like this, this, this, and this). 合わせて十二個の歯車で較正されております(Altogether, it’s comprised of 12 gears).
    これらの歯車は,全て,連合すとり,どれが一つを回すと,全ての歯車が回りようになっております(These gears, altogether & combined, revolve when any one gear
    is turned). それでは,回しています(And so, it turns)…..[ 回転中(revolving)]…..元に戻りました(And it’s back to it’s original form). 十五の歯車が,二回転,十の歯車が, 三回転で,元に戻るようになっております(Upon the 15 tooth gears revolving twice, and the ten tooth gears revolving three times, it
    all returns to it’s original form (the heart)). …..[ 回転中 (revolving)]…
    ..元に戻りました(..and it’s back to the original form). 以上です! (That’s all!)”

    My understanding is that there are indeed separate axles attached to the main vertical one, even though he did not state so. I’ll be reading his website to see if he gives any make information, but none yet.


    P.S.- I love the revitalized Hackaday! Keeps me thinking for projects up here in Sapporo.


    (last post, I promise!)- You can’t buy it, but according to the Japanese on his site, he will have a book out for sale from December, and I think it may have how to make these in it! I guarantee it’s only in Japan, though.

    According to his Japanese site, he originally wanted to cover a sphere with gears, and he did, but then he created this as a masterpiece- and it won a special prize at the World Karakuri Contest (karakuri is a Japanese term encompasing things like trick mechanism/complex mechanism/surprise movement)

  9. Its amazing to see this.Let me know whether these are symmetric or asymmetric gears. Asymmetric in the sense pressure angle on drive side and coast side are differernt.If so How these gears are manufactured ?

    Thanks and waiting for reply.



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