

It's time to build the Analytical Engine - jgrahamc
http://blog.jgc.org/2010/09/its-time-to-build-analytical-engine.html

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wccrawford
While I think it would be interesting, I don't think it's worth the cash
outlay.

Build a virtual model of it and have educational/informational bits that
explain it, instead. That will allow virtual disassembly of the machine for a
better look at how it works.

It'll be both cheaper and better to make a virtual version.

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mechanical_fish
I think this is one of those good and bad ideas.

On the one hand, the point of having a steam-powered computer is to _have a
steam-powered computer_. What fun is a virtual steam-powered computer? You
can't scald anyone with _that_!

On the other hand, yes, in the year 2010 you really should master the art of
building the virtual Analytical Engine before you go for the real thing. One
reason, I believe, is that the current draft of the design of the Analytical
Engine is more akin to the world's largest collection of back-of-the-envelope
sketches than to a finished blueprint. There was never one canonical design
for the Engine, because so little of it was ever actually realized in
hardware. Babbage had a lot of fun swapping parts in and out in his
imagination.

So there needs to be a bit of each approach. Build the virtual version first,
in an environment where building 1024 identical custom-machined ratchets and
pawls is just a matter of ten copy-and-pastes. Then a nail down a plan for
what you intend to realize in hardware. And _then_ build it. If you can find
the money.

There will also have to be some back-and-forth. One of the central lessons of
engineering is that it's more than just CAD. It isn't until you try to build a
thing that you fully understand its design, if only because it is difficult to
imagine the constraints that reality imposes on your design -- and, more
embarrassingly, that the earlier parts of your construction impose on the
later parts -- until you've actually gotten into the middle of the job. This
is one reason why these projects are so expensive: They are, in part, research
projects. I believe that the folks who assembled the Difference Engine weren't
entirely sure, going in, that the darned thing was actually going to work as
well as it does. And they made some crucial tweaks during the assembly
process.

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jgrahamc
There is an emulator here: <http://www.fourmilab.ch/babbage/contents.html>

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mechanical_fish
Okay, then, to the machine shop! ;)

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arethuza
Even better - to the 3D printers!

Printing an Analytical Engine would be rather cool.

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michael_dorfman
Another brilliant idea from jgc. I hope you're as successful in this one as
you were with the Turing apology.

I imagine the first step is to get someone with name recognition to donate a
sizable enough chunk of change to get some news coverage. Any candidates?

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dugmartin
The first thing I did on my last trip to London was to head straight for the
Science Museum and check out the Difference Engine they have on display there.
It was awesome along with the other examples of mechanical calculators and
early computers they had in the same room.

I agree thought that first a virtual model should be built, but only if it
runs as a physical model of it in 3d, and not as an instruction emulator. Once
the bugs are worked out in the virtual model _of course_ a steam powered
version needs to be made - at that point I think you could get bankrolled by a
museum.

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grandalf
I agree. Also, this seems like a great use for CAD drawings fed into one-off
3D fabrication printing.

edit: seems like someone else suggested this below

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jasondavies
There are some cool Babbage-related meccano models here:
<http://www.meccano.us/>

One of them is a "barrel" for the Analytical Engine:
<http://www.meccano.us/analytical_engine/index.html>

There are also fully working models of the Difference Engine e.g.
<http://www.meccano.us/difference_engines/rde_2/index.html> although I think
they had to make some modifications due to the limitations of Meccano!

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pinto
Theres a definite UK angle to the project , so you might be able to get some
matching government funding to whatever you raise elsewhere if you were set up
as a "proper" charity .

Eg ,
[http://www.hlf.org.uk/ourproject/projectsbysector/industry/P...](http://www.hlf.org.uk/ourproject/projectsbysector/industry/Pages/index.aspx)

"We have given more than £770 million to over 2,200 conservation and activity
projects in the industrial, maritime and transport heritage sector."

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mcav
You should put this on Kickstarter. From your blog's comments, it looks like
you might be able to generate some non-negligible funding.

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jgrahamc
Kickstarter requires a US bank account, is in $ and won't accept charities. I
think it's a non-starter for this as I don't imagine it being commercial.

