7 ms·

Reverse-engineering the Globus INK, a Soviet spaceflight navigation computer

168 points by Stratoscope 4y ago

Stratoscope 4y ago
> The Globus INK is a remarkable piece of machinery, an analog computer that calculates orbits through an intricate system of gears, cams, and differentials. It provided astronauts with a high-resolution, full-color display of the spacecraft's position, way beyond what an electronic space computer could provide in the 1960s. If nothing else, at least skim through this article to see the photos. It really was quite a remarkable and beautiful piece of machinery!
- kens 4y ago
  Thanks! I'm glad you enjoyed it.
- z3c0 4y ago
  Analog computers have such an elegance to them. I've wondered if we'll ever seen them return for specialized purposes, outside of music.
  - bitL 4y ago
    There are attempts to solve hard optimization problems in an instant with them.
  - tiedieconderoga 4y ago
    You've probably already seen it, but there's a classic US Navy training film which talks about how they were used to solve differential equations in battleships around the WWII era. https://youtube.com/watch?v=gwf5mAlI7Ug https://youtube.com/watch?v=gwf5mAlI7Ug
fathyb 4y ago
This is coolest thing I've read all year. It's fascinating to see all the work that went through a single instrument.
- Nosignificance8 4y ago
  So many fascinating facts about this! Did you know this had used gyroscopes to calculate the position and orientation of the spacecraft in orbit. It was designed to operate in the harsh environment of space, where temperatures could range from -100 to +150 degrees Celsius. And the thing only weighed 10kg! And super duper reliable I believe it had a mean time between failures of about 10,000 hours. Old yet still so impressive! Thanks for this!
Drblessing 4y ago
For someone who grew up with the internet the fact this is mechanical blows my mind.
- chiph 4y ago
  Check out the video below from Marc where he works on his Model 19 Teletype. Teletypes used a serial to parallel converter comprised of a solenoid and a multi-lobe camshaft that converted an incoming electrical signal (serial) into 5 individual bits (mechanical). Timing was important, so the motor on the Teletype had to be running at a known speed. You used a tuning fork that had a slot cut in it to look through to check it periodically. Marc mentions how Teletypes would commonly run with one or 1.5 stop bits. You need this to tell the mechanical parts to "lock up" at the end of a character. Preferred would be to run with 1.5 stop bits so that the machines became self-synchronizing -- if the wire got reconnected in the middle of a character they would start producing readable output again after only a few garbled characters. The way the camshaft worked was each bit had a window of time where it could be set or cleared (marking vs spacing) by the solenoid. For letter H the bits are 10100 [0]. So the first lobe of the camshaft would come around and the solenoid would be in it's marking position (1) so the 1st bail would be selected. The second lobe would come around a few milliseconds later and the solenoid would be in it's spacing position (0) and the 2nd bail would NOT be selected. A few milliseconds later the third lobe would come around and the solenoid would be in it's marking position (1) so the 3rd bail would be selected. This would continue for the next two bits (spacing) and then the stop bit would arrive and the machine would use the values stored in the bails to print the letter H and/or punch an H (10100) into the paper tape. https://www.youtube.com/watch?v=ug5lUI-hs3s https://www.youtube.com/watch?v=ug5lUI-hs3s Ever wonder why carriage return and line feed are different codes in Baudot, ASCII, and Unicode? It's because Teletypes needed the time to physically move the printing carriage back to column 1. Operators were trained to hit CR CR LF in case the Teletype at the other end was a little slow in returning from column 80 so the next line would start in column 1. [0] Assuming you were in Letters. Because you only had 5 bits, alphabetic (Letters) and numbers/symbols (Figures) were alternately selected by 11111 and 11011. So 10100 could produce either an H or a # depending on whether you were in Letters or Figures mode.
  - 4y ago
frostyj 4y ago
sometimes you do wonder how USSR, with all these mad scientists and engineers, could ever go down
- sureglymop 4y ago
  To be fair they were facing pretty much the entire rest of the worlds fight against "evil communism". It's more remarkable how far they got with essentially a new way of trying things.
  - heywhatupboys 4y ago
    [flagged]
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    - deleted 4y ago
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  - smdyc1 4y ago
    [flagged]
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  - jacquesm 4y ago
    What a nonsense.
    - ChuckNorris89 4y ago
      It's not nonsense that during the cold war the US & allies put sanctions and trade embargos in place for the USSR & Warsaw pact countries, similar how we have with Russia today, meaning their goods had a limited export market, plus they had restrictions on high tech imports as well leading to the Toshiba-Kongsberg scandal. Also, with the USD being the global reserve currency, the USSR & Co. were dependent on the USD for trade.
FredPret 4y ago
Very impressive. I wondered how this could possibly work, but it actually only does fixed circular orbits by dead reckoning
stargrazer 4y ago
One of the museums has one of the early aircraft based mechanical inertial guidance systems on display. Seems it was two or three or four times larger than this. It would be interesting to find a similarly detailed analysis of how those things operated.
deleted 4y ago
[deleted]
akash5459 4y ago
[flagged]
- Stratoscope 4y ago
  Friend, I understand your desire to promote your website. But the article you linked has not even the slightest relationship to this one. That's not what we do here. You can expect that your comment will be marked [flagged] [dead] in the next few minutes. If you ever want to contribute any on-topic comments, I am sure they will be welcomed.
DiscourseFan 4y ago
I am reminded of the Antikythera mechanism here. It's fascinating to think that computing technology has been around so long, its just that transistors allowed for its rapid advancement and higher level logic programming. But we could still do a lot without silicone parts.
blululu 4y ago
That is very cool. I remember seeing a post on this and there was a line of thinking to the tune of "modern engineers are no where near as impressive as the ones 50 years ago". Someone woking in astronautical engineering asking a basic question about how this would handle things like eccentricity, procession of nodes, etc, and the response was simple: "it doesn't!". Honestly these things are really cool I would totally go for a trackball globe being spun around by some Arduino controlled rollers. Even without the gears a modern recreation would be a really cool thing.

168 points by Stratoscope 4y ago

> The Globus INK is a remarkable piece of machinery, an analog computer that calculates orbits through an intricate system of gears, cams, and differentials. It provided astronauts with a high-resolution, full-color display of the spacecraft's position, way beyond what an electronic space computer could provide in the 1960s. If nothing else, at least skim through this article to see the photos. It really was quite a remarkable and beautiful piece of machinery!

kens 4y ago
Thanks! I'm glad you enjoyed it.
z3c0 4y ago
Analog computers have such an elegance to them. I've wondered if we'll ever seen them return for specialized purposes, outside of music.
- bitL 4y ago
  There are attempts to solve hard optimization problems in an instant with them.
- tiedieconderoga 4y ago
  You've probably already seen it, but there's a classic US Navy training film which talks about how they were used to solve differential equations in battleships around the WWII era. https://youtube.com/watch?v=gwf5mAlI7Ug https://youtube.com/watch?v=gwf5mAlI7Ug

fathyb 4y ago

This is coolest thing I've read all year. It's fascinating to see all the work that went through a single instrument.

Nosignificance8 4y ago
So many fascinating facts about this! Did you know this had used gyroscopes to calculate the position and orientation of the spacecraft in orbit. It was designed to operate in the harsh environment of space, where temperatures could range from -100 to +150 degrees Celsius. And the thing only weighed 10kg! And super duper reliable I believe it had a mean time between failures of about 10,000 hours. Old yet still so impressive! Thanks for this!

Drblessing 4y ago

For someone who grew up with the internet the fact this is mechanical blows my mind.

chiph 4y ago
Check out the video below from Marc where he works on his Model 19 Teletype. Teletypes used a serial to parallel converter comprised of a solenoid and a multi-lobe camshaft that converted an incoming electrical signal (serial) into 5 individual bits (mechanical). Timing was important, so the motor on the Teletype had to be running at a known speed. You used a tuning fork that had a slot cut in it to look through to check it periodically. Marc mentions how Teletypes would commonly run with one or 1.5 stop bits. You need this to tell the mechanical parts to "lock up" at the end of a character. Preferred would be to run with 1.5 stop bits so that the machines became self-synchronizing -- if the wire got reconnected in the middle of a character they would start producing readable output again after only a few garbled characters. The way the camshaft worked was each bit had a window of time where it could be set or cleared (marking vs spacing) by the solenoid. For letter H the bits are 10100 [0]. So the first lobe of the camshaft would come around and the solenoid would be in it's marking position (1) so the 1st bail would be selected. The second lobe would come around a few milliseconds later and the solenoid would be in it's spacing position (0) and the 2nd bail would NOT be selected. A few milliseconds later the third lobe would come around and the solenoid would be in it's marking position (1) so the 3rd bail would be selected. This would continue for the next two bits (spacing) and then the stop bit would arrive and the machine would use the values stored in the bails to print the letter H and/or punch an H (10100) into the paper tape. https://www.youtube.com/watch?v=ug5lUI-hs3s https://www.youtube.com/watch?v=ug5lUI-hs3s Ever wonder why carriage return and line feed are different codes in Baudot, ASCII, and Unicode? It's because Teletypes needed the time to physically move the printing carriage back to column 1. Operators were trained to hit CR CR LF in case the Teletype at the other end was a little slow in returning from column 80 so the next line would start in column 1. [0] Assuming you were in Letters. Because you only had 5 bits, alphabetic (Letters) and numbers/symbols (Figures) were alternately selected by 11111 and 11011. So 10100 could produce either an H or a # depending on whether you were in Letters or Figures mode.
- 4y ago

frostyj 4y ago

sometimes you do wonder how USSR, with all these mad scientists and engineers, could ever go down

sureglymop 4y ago
To be fair they were facing pretty much the entire rest of the worlds fight against "evil communism". It's more remarkable how far they got with essentially a new way of trying things.
- heywhatupboys 4y ago
  [flagged]
  - deleted 4y ago
    [deleted]
  - deleted 4y ago
    [deleted]
- smdyc1 4y ago
  [flagged]
  - deleted 4y ago
    [deleted]
- jacquesm 4y ago
  What a nonsense.
  - ChuckNorris89 4y ago
    It's not nonsense that during the cold war the US & allies put sanctions and trade embargos in place for the USSR & Warsaw pact countries, similar how we have with Russia today, meaning their goods had a limited export market, plus they had restrictions on high tech imports as well leading to the Toshiba-Kongsberg scandal. Also, with the USD being the global reserve currency, the USSR & Co. were dependent on the USD for trade.

FredPret 4y ago

Very impressive. I wondered how this could possibly work, but it actually only does fixed circular orbits by dead reckoning

stargrazer 4y ago

One of the museums has one of the early aircraft based mechanical inertial guidance systems on display. Seems it was two or three or four times larger than this. It would be interesting to find a similarly detailed analysis of how those things operated.

deleted 4y ago

[deleted]

akash5459 4y ago

[flagged]

Stratoscope 4y ago
Friend, I understand your desire to promote your website. But the article you linked has not even the slightest relationship to this one. That's not what we do here. You can expect that your comment will be marked [flagged] [dead] in the next few minutes. If you ever want to contribute any on-topic comments, I am sure they will be welcomed.

DiscourseFan 4y ago

I am reminded of the Antikythera mechanism here. It's fascinating to think that computing technology has been around so long, its just that transistors allowed for its rapid advancement and higher level logic programming. But we could still do a lot without silicone parts.

blululu 4y ago

That is very cool. I remember seeing a post on this and there was a line of thinking to the tune of "modern engineers are no where near as impressive as the ones 50 years ago". Someone woking in astronautical engineering asking a basic question about how this would handle things like eccentricity, procession of nodes, etc, and the response was simple: "it doesn't!". Honestly these things are really cool I would totally go for a trackball globe being spun around by some Arduino controlled rollers. Even without the gears a modern recreation would be a really cool thing.