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The vacuum isn't what I'd worry about; I'd worry about the radiation. I thought that space stuff usually used ancient CPUs because they had to be rad-hard in
by lsc 15y ago
The vacuum isn't what I'd worry about; I'd worry about the radiation.
I thought that space stuff usually used ancient CPUs because they had to be rad-hard in ways that stuff beneath the ionosphere doesn't need to be, and creating a sufficently rad-hard CPU was difficult and time consuming (thus you end up with what was state of the art when you started working on it, some time ago)
- Synaesthesia 15y agoYeah, I'm sure almost any phone will survive a hard vacuum.
- Someone 15y agoWhy are you sure? Things that could go wrong I can think of: - capacitors leaking. - gas bubbles in various parts. - heat problems due to lack of convective cooling.
- ams6110 15y agoTrue but there's also a difference, you're not controlling a multi-billion dollar piece of hardware, perhaps containing astronauts; your tolerance for failure due to radiation can probably be higher for a hobbiest science experiment.
- faboo 15y agoPlus, using an off-the-shelf device means there's a whole bunch of stuff you don't have to build from scratch - even if it also contains a whole bunch of stuff you wouldn't have built if you did it from scratch.
- pointyhat 15y agoAgreed: One sunspot or gamma ray burst and your Nexus One will stop working very rapidly. The "age" of rad hardened devices is pretty much limited by the processes used. Only simpler designs work well. The finer the traces, the more charge-related problems occur and the less reliable they will be. Also, there's not much interest in making it better because it works fine as it is. If you take away the JVM, most of the OS, the graphics stack, comms layer and all the fancy abstractions from the Nexus One and Android OS, a 1MHz RCA 1802 is fine ;-) Simple is good enough though when you read a bit of telemetry and you use low bandwidth RF comms. Also the Nexus is a really bad idea as it contains FLASH, which if you fart any radiation near, it flips bits like crazy.
- sasvari 15y agoagreed. but the radiation in low-earth orbit, at least at the altitude they seemed to have shot the phones, is usually not intense enough to destroy commercial electronic devices (instantly). we just finished a radiation susceptibility test for a commercial IC supposed to fly on a satellite in low-earth orbit (which you can find in a lot of consumer electronic products): no serious performance degeneration occured while exposed to a much higher total dose than expected during the lifetime of the satellite. EDIT: if you're interested in the effects of radiation on electronic devices/components in low-earth orbit, check [0]. [0] http://klabs.org/DEI/References/design_guidelines/design_series/1258jsc.pdf http://klabs.org/DEI/References/design_guidelines/design_ser... [pdf]
- sandGorgon 15y agocan you not put shielding AROUND the device, rather than build hardened processors ? I can think of one reason - increases weight of the whole package - but perhaps the corresponding cost increase is not so much as buying a radiation hardened 1Ghz processor.
- sasvari 15y agoyou can't shield your devices from every type of radiation up there with a reasonable sized shield. so yes, it's about weight.
- ericHosick 15y agoOne of the interesting things is that there is some really high energy particles running around in space. If you have a lot of shielding, you risk these particles hitting that shielding causing a cascading effect making things worse (My father designed satellites and we used to chat about this stuff when I was a kid).