Working 3 digit mechanical computer built from LEGO Technic...

A truly stunning achievement! Charles & Ada would be proud of you. Not wishing to get you to start rebuilding or anything but what does it do if b^2

It's very impressive. I sent the link to our High Performance Computing group, so they can see how to make real calculators. :-)

I didn't quite understand how it works. I suppose it takes a bit of experimenting to figure it out. Please let us know, if you expand the explanation.

Play well,

Jacob

Andy:

What a fascinating thing this is. I gave a quick study of the device and am amazed what can be built with Lego. Being a student of mathematics myself, this is really quite exciting!

Great Work!

Best Regards,

Mark

Your table:

f(x) x 2*x^2 + 3*x + 5 First Difference Second Difference

Why don't you look @ it this way:

f(x) = a*x^2 + b*x + c

First Differance: a*(2x-1) + b Second Differance: a*2

Always...

:) Wouter

Some of us over in LUGNET noticed it as well - *very* nice, and a lot of us are very curious about the details. It needs about a 100 turns?!? Use an RCX as a dumb battery box to motorize it ;-). Someone on LUGNET also recently posted a working knitting machine. Now we need the machine inbetween (Jaquard [sp?] loom).

I'm guessing that's becuase lego gears are small and weak. A big gear for a big crank would probably help a lot.

The one I've seen:

Elijah

------ can see a Jacquard loom being much more difficult

There is a LOT of friction in moving 200 gears, along with the mechanisms they drag along. There is also a detent which causes each digit to "click" into place.

The original Babbage design was 1:1. The version of his machine made by the London Museum was 1:4. Mine is about 1:105

On the other hand, the movement is very smooth and light. Part of the issue is that I only have a specific set of gear sizes available. I would have been happy to have 1:80, but I had a choice between too low or too high and too high simply won't work, so I'm stuck with too low.

--- Andy

You are correct that would be more general. I did it with actual numbers simply for the ease of conveying the basic principle to people who want an overview of how the machine works.

--- Andy