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Interesting related tidbit - Most sophisticated computers would instantly fail when exposed to outerspace. The process of making them rad tolerant is expensive
by jjcon 4y ago
Interesting related tidbit - Most sophisticated computers would instantly fail when exposed to outerspace. The process of making them rad tolerant is expensive and complicated. Using simpler chips makes it easier and means there is less that can go wrong. This is why most space bound computers even today appear on the surface spec sheet to be out of date.
- 4oo4 4y agoThat never made sense to me until I really learned about bit flips, and how the smaller the process node, the more susceptible it is. They are at least up to PowerPC with the most recent Mars missions, probably not a terrible tradeoff of computing power vs. radiation vulnerability. https://www.macrumors.com/2021/03/02/nasa-mars-perseverance-rover-imac-powerpc/ https://www.macrumors.com/2021/03/02/nasa-mars-perseverance-...
- kam 4y agoThe Mars Helicopter Ingenuity actually has a 2014-era 2.2GHz ARM phone SoC, the Snapdragon 801 (same chip as the Galaxy S5 and OnePlus One) https://rotorcraft.arc.nasa.gov/Publications/files/Balaram_AIAA2018_0023.pdf https://rotorcraft.arc.nasa.gov/Publications/files/Balaram_A...
- 4oo4 4y agoWow that's crazy, since I'd imagine SoCs to be the most vulnerable to bitflips.
- wrycoder 4y agoHere are details on the Voyager computers: https://www.allaboutcircuits.com/news/voyager-mission-anniversary-computers-command-data-attitude-control/ https://www.allaboutcircuits.com/news/voyager-mission-annive...
- SEJeff 4y agoThat was popular understanding until Spacex used normal intel chips for most of their flight hardware. They have the computers generally in triplicate do a bit flip in one doesn’t cause issues, and it is many times more cost effective.