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A comment on Playing with model trains and calling it graph theory.

Re:Playing with model trains and calling it graph theory by dekhn on Friday May 03, 2019 @11:05AM (#19819058)
The book Hackers has an entire chapter on the TMRC https://en.wikipedia.org/wiki/Tech_Model_Railroad_Club engineers (students) build early track switching systems using relays and mainframes (later I think it was transistors and later microcomputers). This let them experiment with all sorts of train routing algorithms and those students often went on to influential positions in the telecom and computing industries.
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Re:Playing with model trains and calling it graph theory by jpmattia on Friday May 03, 2019 @05:37PM (#19822523)
While we're on the subject of ancient history, Prof Jim Roberge's course on feedback systems (6.302) famously included a final lecture incorporating his love of model trains.

The goal of the lecture was that the train should have a constant speed despite hills introduced into the track. In order to measure the speed of the train, he noticed that there was a small glitch that would occur as the motor's armature switched polarity, and so a time measurement of the glitches was proportional to the speed of the engine.

[I took the course in 85 and still remember it, so he left something of an impression. A couple of generations learned analog feedback from this course. RIP Prof Roberge.]

Edit: By some lesser miracle, his lectures are on youtube. The train lecture was last.

https://www.youtube.com/playlist?list=PLUl4u3cNGP62in17jH_Di...

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Re:Playing with model trains and calling it graph theory by dekhn on Friday May 03, 2019 @06:16PM (#19822755)
Thanks, that's pretty cool. When I was a kid I could never get my model train to go very fast. It wasn't until about 30 years later that I learned enough EE to understand the problem. Eventually I learned enough to build a self-balancing robot using PID control but I'm always amazed at college students who can do this stuff easily.
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Re:Playing with model trains and calling it graph theory by petemcc on Friday May 03, 2019 @12:35PM (#19819871)
* https://en.wikipedia.org/wiki/Tech_Model_Railroad_Club

(above breaks with the bracket included)

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