Discussed at the time (of the article):
Apollo 11 Guidance Computer vs. USB-C Chargers - https://news.ycombinator.com/item?id=22254719 - Feb 2020 (205 comments)
Apollo 11 vs. USB-C Chargers (2020)
71–80 of 209 posts
Re: Apollo 11 vs. USB-C Chargers (2020)
#72Earlier quoted context omitted.
That sounds way too low. Modern fly-by-wire planes are said to have 12-way voting.
> Modern fly-by-wire planes are said to have 12-way voting Do you have a source for that? Everything I've ever read about Airbus says the various flight control systems are doubly redundant (three units). Twelve sounds like it would be far beyond diminishing returns...
That was word of mouth.
This website says 5 independent computers, of which 2 use different hardware and software so as not to fail in the same fashion.
https://www.rightattitudes.com/2020/04/06/airbus-flight-cont...
I'd imagine every computer relies on redundant stick/pedal encoders, which is how a 12-way notion appeared.
Re: Apollo 11 vs. USB-C Chargers (2020)
#73Re: Apollo 11 vs. USB-C Chargers (2020)
#74> Apollo 11 spacecraft contains 4 computers Analog computers don't get the respect they deserve. There's one more computer, the FCC. The Flight Control Computer is an analog computer in the Saturn V that controlled the rocket gimbals. It's a two-foot cylinder weighing almost 100 pounds.
You forgot the most important one, the human computers at ground control. Who said women can't do math? https://www.smithsonianmag.com/science-nature/history-human-...
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Re: Apollo 11 vs. USB-C Chargers (2020)
#75So in 50 years the equivalent of a gpt4 training cluster from today's datacenters will fit in a cheap cable, and it will run over 100 times faster than a full cluster today.
Re: Apollo 11 vs. USB-C Chargers (2020)
#76Earlier quoted context omitted.
In the context of this thread, I believe even a digital computer would have to be rebuilt if the program is wrong... :P Unless you typically salvage digital computers from the wreckage of a failed rocket test and stick it in the next prototype. If the FCC is wrong, kaboom.
Presumably they meant a program being discovered to be wrong before the computer was actually launched. And meant literally building a whole new computer, not just recompiling a program.
For the Apollo Guidance Computer, changing the program meant manually re-weaving wires through or around tiny magnet rings. A good part of the cost of the computer was the time spent painstakingly weaving the wires to store the program.
Re: Apollo 11 vs. USB-C Chargers (2020)
#77Too bad the link to Jonny Kim's biography is broken (one that works: https://www.nasa.gov/people/jonny-kim/). He has to be one of the most impressive humans who has ever lived. Amongst other things, a decorated Navy SEAL, Harvard medical doctor, and astronaut. Sounds like a kid slapping together the ultimate G.I. Joe.
Re: Apollo 11 vs. USB-C Chargers (2020)
#78Earlier quoted context omitted.
> Modern fly-by-wire planes are said to have 12-way voting Do you have a source for that? Everything I've ever read about Airbus says the various flight control systems are doubly redundant (three units). Twelve sounds like it would be far beyond diminishing returns...
That was word of mouth. This website says 5 independent computers, of which 2 use different hardware and software so as not to fail in the same fashion. https://www.rightattitudes.com/2020/04/06/airbus-flight-cont... I'd imagine every computer relies on redundant stick/pedal encoders, which is how a 12-way notion appeared.
That blog isn't very authoritative, and doesn't go into any detail at all.
> I'd imagine every computer relies on redundant stick/pedal encoders, which is how a 12-way notion appeared.
That's disingenuous at best. The lug nuts on my car aren't 20x redundant... if you randomly loosen four, catastrophic failure is possible.
Re: Apollo 11 vs. USB-C Chargers (2020)
#79Pretty much all USB chips have a fully programmable CPU when you go into the data sheets. It feels silly for simple hid or charging devices but basic microcontrollers are cheap and actually save costs compared to asics.
I would also argue that this is another example of software eating the world. The role of the electrical engineer is diminished day by day.
The role of the non-software engineer, bit just electrical
Re: Apollo 11 vs. USB-C Chargers (2020)
#80Earlier quoted context omitted.
I would also argue that this is another example of software eating the world. The role of the electrical engineer is diminished day by day.
Nah - there are lots of places where you need EEs still. Anything that interfaces with the world. Having programmability does not move most challenges out of the domain of EE. Much of it is less visible than the output of a software role perhaps.
There will always be problems that can only be solved by an EE, chem eng, mech eng, etc.
But the juiciest engineering challenges involve figuring out business logic / mission decisions. This is done increasingly in software while the other disciplines increasingly make only the interfaces.