math-meets-machines

[Thomas Puettmann]

Hi all,

I am a long-time occasional reader of this forum and want to express my thanks to all the contributors. I think the forum and the main site hpmuseum.org itself are a great source of useful information and also quite entertaining. I benefitted several times of them.

I own a HP 35 (inherited from my father), two 11Cs, a 41CX and a 42S. After the 42S, I stopped buying calculators since it became pointless in my opinion. I now exclusively use one of my 11Cs. For any task beyond its capabilities I would use a computer.

I have recently started a long-term project called math-meets-machines where I develop and document models in which math and mechanics interact exemplarily in an instructive way. The first two models are actually mechanical calculators that share a lot of properties with our beloved HP machines: They are durable, reliable, have a carefully designed user interface, non-algebraic entry and run forever without need to change batteries. If you are interested, take a look at http://www.math-meets-machines.de or at my YouTube channel.
So far, there are only two models on the site but many more already exist. They will be posted one by one as soon as I get the time-consuming documentation done. I would be glad if at least some people here like these devices!

Thomas

[Joe Horn]

I like the 4-bit binary adder's overflow bell and visible bit bucket!

[Marcus von Cube]

Hallo Thomas,

I like it. :-)

There is no need to drop the bits in the adder simultaneously. You can just add one bit at a time and get the same result. This should avoid any accidental interference between the balls.

[Paul Dale]

I really think I should make one of these someday....


- Pauli

[Thomas Puettmann]

Hi, and thanks for the positive feedback.

The overflow bell at the binary adder is in fact essential for exciting the interest of children. I exhibited some of my machines twice to a broader public and particularly children between the ages of 8 to 12 like to play with the binary adder and get an intuitive understanding of binary numbers. They always like the bell the most.

For children it is indeed important that you can drop the balls one by one into the adder. In the video, I just did it simultaneously because I wanted to sync the input and the writing on the right. No interference is possible when you drop them simultaneously. The possible carries from upstairs always arise later. For this reason there is no need to distinguish between half adders and full adders as in electric circuits.

Paul, when I first read about the WP 34s here in this forum I immediately wanted to have one. But unfortunately, some hours later my mind said: you don't have time to spend on things that you don't actually need, you need some flashing cable, you have a PPC mac that is way to old to run the flashing software.... So I haven't converted any HP 30b into a WP 34s until now and might perhaps never do. But I did enjoy the spirit of the project very much. Conversely, I would of course be very happy about anyone rebuilding my machines, but I am also happy if someone just likes the spirit.

Anyway, rebuilding the models will become much more worthwhile in the future as the number of models grows. I plan to write a book about the models, what one can learn from them, and how they relate to parts of the history of mathematics and technology. If there is sufficient interest something like a construction kit might perhaps also be possible.

[Marcus von Cube]

(10-24-2014 10:19 PM)Thomas Puettmann Wrote:  Paul, when I first read about the WP 34s here in this forum I immediately wanted to have one. But unfortunately, some hours later my mind said: you don't have time to spend on things that you don't actually need, you need some flashing cable, you have a PPC mac that is way to old to run the flashing software.... So I haven't converted any HP 30b into a WP 34s until now and might perhaps never do. But I did enjoy the spirit of the project very much.

I can certainly help you out if you like. Where in Germany are you?

[Paul Dale]

(10-24-2014 10:19 PM)Thomas Puettmann Wrote:  Paul, when I first read about the WP 34s here in this forum I immediately wanted to have one. But unfortunately, some hours later my mind said: you don't have time to spend on things that you don't actually need, you need some flashing cable, you have a PPC mac that is way to old to run the flashing software.... So I haven't converted any HP 30b into a WP 34s until now and might perhaps never do. But I did enjoy the spirit of the project very much. Conversely, I would of course be very happy about anyone rebuilding my machines, but I am also happy if someone just likes the spirit.

I know this feeling all too well. It took me a while to learn this and I've still got several unfinished projects I never find time to work on


Still, I've got an interested in mechanical devices and their relations with mathematics and have made a few before (Console is a lovely one that knows his multiplication and addition tables; and quite a number of orreries of various kinds).

Fischertechnik isn't readily available in Australia but I do have a bit of Meccano and Märklin Metallbaukasten which would also be quite suitable.

Tim Robinson has made a number of complicated mechanical computers which I'd love to try but doubt I ever will. I don't need more unfinished things around


- Pauli

[Thomas Puettmann]

Marcus, I live in Bochum. Thanks a lot for offering help. This might be a project for Christmas vacation and I might fall back on your help then. I guess the last 30bs are not sold until then.

Paul: Awesome orreries! I guess you know the book "Geared to the stars" by Henry Charles King? I saw an original Consul, the Educated Monkey in the Arithmeum, Bonn, and like your version very much.

[Paul Dale]

(10-26-2014 07:16 PM)Thomas Puettmann Wrote:  Paul: Awesome orreries! I guess you know the book "Geared to the stars" by Henry Charles King? I saw an original Consul, the Educated Monkey in the Arithmeum, Bonn, and like your version very much.

I hadn't heard of that book. Will try to locate a copy.


Over the last two and a half decades a small number of Meccano enthusiasts have made huge progress building orreries. I think it safe to say that the results are the most accurate, non-digital, orreries.


I've built a fair number of other orrery models but haven't uploaded any photographs.


Pauli