aeh5040

(Sorry for the poor video, it's from 10 years ago!)

That's a wonderful joystick mechanism! Never seem one quite like that before.

I have a special affinity for that set, as it was my out-of-the-dark-age experience. But I think it's amazing even by objective standards. I really like the way form and function come together, and every piece is important...

Definitely still relevant to some of us! I'll just mention the stunning 8480:

Awesome work!

Nice idea!

Interesting discussion! Building official sets its not really something I find challenging, it is certainly something I enjoy. I find it quite relaxing, and I am sometimes quite amazed by the ingenious constructions that the designers come up with. But yes, if you want real challenge and fulfillment, design you own models, ideally of something that has never been done before!

As others have said, the obvious solution is simply to ask the model creator before making such material public. I can't understand why anyone wouldn't want to do that - it's just good manners. It's highly likely that the creator would agree, and then everyone is happy!

Just Wow. I am simply astonished that this is possible. Congratulations!! I would be interested to see what the parts looks like afterwards. Is there much gear wear or axle twisting?

Great idea - it would be very interesting to see how well this can work. I say go with whatever design flies best, and fine tune it! Could a powered launcher be possible...?

That's a very impressive and clean build! And very interesting discoveries on the turntable...

That's a great idea! I like how you even used a 28t turntable (pity there's no 32t gear, or you could go two more). About the issue with staying in gear, could it work to put a towball or something similar in the other 4 holes of the pulley, to lock the wheels in place?

I've put some pictures on bricksafe: http://bricksafe.com/pages/aeh/hanoi

It is indeed pneumatic - the cylinder is attached to a gear rack which turns a gear, similar to Akiyuky's pneumatic GBC module. There are end stops on the rotating part, to achieve the precise angle. It's pretty much all my own invention, although of course there is always inspiration from elsewhere. As I mentioned above, the rotation of the grabber was partly suggested by an Akiyuky module. Also the idea of the intermittent chain-to-knob-wheel drive (which rotates the pegs) has been used before. The concept of a mechanical Hanoi solver (as opposed to computer controlled) is completely new so far as I know. Pneumatic sequencer! Yes indeed, I initially tried to do it that way (I even designed a mechanism to advance the pegs 120 degrees pneumatically), so that it would all be powered by an air supply. Sadly I just could not get anything work reliably enough that way (I'm not quite sure why). Maybe I'll give it another go at some point. I'd also like to have a purely mechanical version (without pneumatics) - I'm working on that, we'll see whether it works. But for now I'm just happy to have any working solution! :D That's exactly right! Of course I'm not the first to observe that this algorithm works (see the wikipedia page). I find it somewhat miraculous that it does, and in the minimum moves! Yes, well spotted. The chain drive is definitely a bit of a weak point. It did survive a weekend running on-and-off at BrickCon, however. Just the end stops. The curve at the end of the liftarms helps too. If it is lowered not quite in the right place it can self-correct a little bit. It does occasionally drop one (once or twice per hour). I think inaccuracy in the chain drive is more often to blame. Good question. No, it will not solve from an arbitrary state. In general it will get into a different loop. For a simple example, if you start with the smallest green disc in the wrong place, it will just shuffle that one round endlessly! It is quite noisy - no reason why one could not do this. You could also move the switches away, but it still needs drive to operate the rotation of the three pegs (which much be synchronized with the switches).

Here is perhaps my most ambitious creation. It's an entirely mechanical (and pneumatic) robot that solves the Tower of Hanoi puzzle (in the minimum moves). There is no computer or electronics, just one motor (plus two more for the compressor). I believe it's the first time such a thing has been done, in LEGO or otherwise. The Tower of Hanoi puzzle, invented by mathematician Edouard Lucas in 1883, is to move a pile of discs from one peg to another, using a third peg, one disc at a time, never putting a larger disc on top of a smaller disc. 5 discs (as here) takes 2x2x2x2x2-1 = 31 moves. 64 discs (in the original formulation of the puzzle) take 2^64-1 = 18,446,744,073,709,551,615 moves. Most robots or programs to solve the puzzle use recursion, but here it is done by repeating a simple sequence of steps: grab, rotate, drop, advance the pegs. The key is that it always grabs the smaller of the two discs in front of it and transfers it to the other peg. It senses which that is by height - the grabber can only drop as far as the higher disc, which is the smaller one because of how the pegs are stepped. The pegs are rotated by a chain drive, while all other actions are controlled by mechanically actuated pneumatic switches. Sorry the video is a bit dark - I'll add some photos of the mechanisms soon.

Moreover, the RTC works much better than the BWE. I think they are both amazing models, but BWE is just on the edge of what's possible, while RTC is robust and playable.

Looks great - I'll get to work trying this...

Wow, this absolutely phenomenal. I am struggling for words! I have thought about such a thing many times, and concluded that it was in practice essentially impossible! (I was quite happy when I managed to implement a one-dimensional cellular automaton mechanically - see below - but yours blows that out of the water). It would be great to see a grid big enough for some interesting configurations. It may well be worth investigating other cellular automaton rules (it seems that you can implement any totalistic rule with the Moore neighborhood). It's likely that some others can give more interesting patterns on a small grid. (Although of course Life has the advantage of being very well known). Please do make a digital file or instructions. I would be very happy to test or help in other ways. https://youtu.be/_52PX3vEntQ

That's epic! I made a smaller version of the mechanism a long time ago (see video below), but it never occurred to my how perfectly the concept fits with GBC! And here is an astonishing piece of automation by the same builder...

Very entertaining and fun project! This is also the direction TLG is heading! #colorvomit

Very nice. Mesmerizing in its awesome simplicity!

Wow, great experiment and great video! I am amazed that it can take so much weight, but those poor parts! To go even further, maybe you could reinforce axles by running them through 2x2 round bricks, or somehow replacing the axle bearings with technic turntables... He's already done 100kg!

Thank you for the nice comments folks. (I was a bit worried it would be too esoteric for anyone to appreciate!) Yes, exactly. You can hook up as many of the units as you want in a ring (or just in a line). The only thing that would need to change is the geometry of the physical bracing and the chain drive. Currently 135 degree angle connectors are used to get the 8-fold symmetry. Interestingly, if the number of units is not a power of two, it would typically take MUCH longer for the pattern to repeat. E.g. with 10 units I think it takes 8890 steps. No reason why not in principle, although it would be harder. Perhaps differentials could be used. Of course, a Turing complete rule would be good! One thing I would like to improve is to replace the yellow "flags" with something larger and more visible (that moves or changes color). The issue is theat it needs to take very little force to activate it. Any ideas welcome...

Most important parts of the mechanism are actually visible in the video, although I understand it's hard to see what is happening! The chain contains four wide track links, and the rest is normal chain. When those four pass the knob wheels at the top of a unit, they rotate the central vertical axle by one turn. The central axle has a driving ring (the new 3L type on the smooth Porsche axle connector), so that depending on the position of a changeover catch the central axle it is connected either to nothing or (via a 1:2 gear ratio) to a crank (Bionical weapon barrel) on the _previous_ unit in the circle. That crank controls the changeover catch of that unit - a half turn toggles the changeover catch to the opposite position. Apart from the gearing (which isn't important except that it is a 1:2 ratio), the only thing not clearly visible is a detent mechanism, which ensures that the crank snaps cleanly into one of two positions 180 degrees apart. (That is essential, otherwise errors would quickly accumulate).