Hacker News Reader

Comment by echoangle | Hacker News Reader

True, I wonder how that would not be a factor, surely they always have stuff they could send up to the ISS as a backup. So if they would have made this 500g lighter, they could have sent 500g more food, for example.

I also can't imagine that the resupply flights are volume limited instead of mass.

View on HN

NASA's 2-year cert for electronics requirement is puzzling. I understand rules about mission critical electronics: you want to (a) depend on it and (b) avoid fire, magic smoke, and blowing breakers on the Station. But for a non-critical application, you don't care about (a) and the risk of (b) from a 5V/2A microcontroller with a worm drive motor seems reasonably remote.

Did you mean to post this under my comment? I don’t see the connection.

Yes - it might have been 500g lighter if it wasn't fully mechanical.

True, but even for a fully mechanical one, the one shown seems very heavy. It looks like weight wasn’t a real concern, which is strange. The plates are very thick and a lot of material could have been removed to reduce weight.

On the other hand, rocket launches produce a lot of vibration, and you don't want it to require fixing on orbit. Astronaut labor time I once saw calculated to cost something like $1M USD/astronaut/day in terms of long-tail logistical support.

Once it's up there, it's a negligible percent of the total spacecraft mass, and might be useful for later astronaut photographers.

Nobody involved wants to take the risk, no matter how trivial

Reply on news.ycombinator.com