7 ms·

This is exactly the whole "agile" vs traditional/waterfall mentality, scooters before motorcars, etc., put into practice. Hardware is hard. > It's also complet

by kortex 5y ago

This is exactly the whole "agile" vs traditional/waterfall mentality, scooters before motorcars, etc., put into practice. Hardware is hard. > It's also completely possible that the parts simply aren't available Fun fact: they don't make (commercially available) GPUs, NICs, pretty much any PC components rated below 0°F. If you need to design a system which needs to sit in an aircraft in Deadhorse, Alaska, you either pay out the nose for some serious engineering, or you just roll the dice. We rolled, and it turned out fine. That won't always be the case. What Spacex is doing is smart, not sloppy.

MichaelApproved 5y ago
> We rolled, and it turned out fine. Who is “we”?
- kortex 5y ago
  Company I worked for. We built an aerial multispectral imaging system for monitoring seals, polar bears, and other mammal populations. It's 3 high power rugged PCs, semi-affixed in a shock mount case in the tail of a Twin Otter. There's no hangars available at the airbases in e.g. Kotzebue, Deadhorse, Utqiagvik, so it sits on the tarmac and experiences some intense temperature swings. It's made it 2 winters and dozens of missions so far. The customer is NOAA and they really don't have oodles of cash to spend on this thing, so it's mostly commodity hardware. Initially we designed this whole crazy insulated case to keep it from getting too cold, but the aircraft engineers nixed it due to fire hazards. The airframe isn't airtight so it gets most of the brunt of the diurnal swing.
  - nr2x 5y ago
    Sounds like a fun job!
    - kortex 5y ago
      It was brilliant fun and also the most stressful period of my life, due to it being a bit far out of our core competencies at the time, delays in getting the camera hardware we had to interface with, limited staffing, and a comedy of other errors. Also the PM gets insanely airsick. As a result of all that, I got to go up to Kotzebue, AK with the PM to do the integration testing. So there I am, hacking like mad in a terminal in the back of this airplane over sea ice, trying to squash various bugs. I blame my love of travel and reading while flying for my resilience to motion sickness. Stressful AF. So worth it.
devit 5y ago
You could also add a heater.
- duskwuff 5y ago
  And, fwiw, that's exactly what SpaceX did to make Dishy tolerant of low temperatures (and to help it clear snow/ice from the dish). There's just no equivalent solution for high temperatures.
  - zamadatix 5y ago
    I used to think it was just a matter of product cost to do active cooling... really the problem isn't the temperature it's the dew point! Which I guess could probably be solved with enough hardware, planning, and cost as well... but a ridiculous amount compared to adding an electric heater for the opposite problem. Come to think of it does anyone know of a consumer device that utilized active cooling (as in would get colder than ambient not just fans or whatnot)?
    - meimo 5y ago
      a fridge
      - zamadatix 5y ago
        I mean electronic device, things in a fridge/freezer generally don't mind condensation or deposition.
    - oceanswave 5y ago
      A pump, a home depot bucket in shade, some duct tape and tubing would probably be sufficient.
    - ficklepickle 5y ago
      Thermoelectric coolers can cool below ambient. You can get them for CPUs, I saw one on a Linus YouTube video. https://en.wikipedia.org/wiki/Thermoelectric_cooling https://en.wikipedia.org/wiki/Thermoelectric_cooling
eyegor 5y ago
Along the same lines, most hardware is designed under the assumption that you aren't significantly above sea level. Tons of medium-high voltage electronics have trouble with arcing once it turns on at 6000+ ft.
- c_o_n_v_e_x 5y ago
  Considering most of humanity lives within an hour's drive of the ocean, it's not a bad assumption.
  - cheschire 5y ago
    I'm interested why you are being downvoted, as you bring up a good point that aligns with what kortex was saying in their post. edit: ahh, now I see it's because you're factually incorrect. It's only 1/3rd of humans that live within 100km of oceanic coasts. https://science.nasa.gov/earth-science/oceanography/living-ocean/ https://science.nasa.gov/earth-science/oceanography/living-o...
- gugagore 5y ago
  arcing involves ionizing air, right? I would have expected that the breakdown voltage of air increases with altitude, due to decreasing density of air.
  - kalnins 5y ago
    I would guess that it could be due to having more ions in air due to higher radiation levels.
  - labawi 5y ago
    It's actually the opposite (to a point, I think). Higher mean free path means more time to accelerate, then hit and ionize something else. That's how fluorescent tubes maintain discharge a meter long at measly voltages. Radiation doesn't help either, as sibling commented - it creates ions making the initial breakdown easier, though it shouldn't make a difference for a continuous flow that involves innumerable ions.
c_o_n_v_e_x 5y ago
Wide temperature (-40C to +85C) DIMM and SSDs are available.. Companies like ATP and Apacer carry them. Intel's Xeon D series are meant for wide temps.
- coolspot 5y ago
  -40C is very close to 0F (-32C) claimed above. Update: -40F is -40C, oops, my bad, I don’t understand Fahrenheit. ¯\_(ツ)_/¯
  - tedunangst 5y ago
    Um, -40C is -40F.
  - barko 5y ago
    -40° Celsius is actually equal to -40° Fahrenheit, it's the temperature at which the two meet. 0° Fahrenheit is about -18° Celsius, did you perhaps multiply 0 by 5/9 then subtract 32 instead of the other way around?
- tigershark 5y ago
  The starlink dish is rated to -30C so it’s not that bad on the freezing side.
fnord77 5y ago
I wouldn't want to roll the dice when it comes to aircraft
- kortex 5y ago
  The hardware is an imaging system (see other comment). It does not impact flight avionics in any way, and is on an isolated power source. The flight engineers wouldn't let us roll the dice on anything mission critical. They did make us redo a bunch of wiring harnesses to use non-smoke-producing wires, for example.
systemvoltage 5y ago
"Hardware is hard", I would say Manufacturing is hard.
double0jimb0 5y ago
That expensive part is NRE and only making a few tens of them, no production efficiency. With the volumes spacex will be hitting, efficiencies will certainly be found and NRE exceptionally better amortized.
foobiekr 5y ago
No, it’s not. Ignoring perfectly predictable issues because you can’t even learn from recent history (millions of sat tv dishes in the nineties) or from industry (literally millions of cellular antennas) is not “smart.” Also your example is a poor one. Engineering a systems solution for 0F is far easier than engineering for outdoors in the sun. Heat removal is a primary consideration and a 0F environment makes that far easier. In 0F your issue isn’t the cold, it’s the lack of humidity - again, something everyone who has more than two years in HW knows.

by kortex 5y ago

MichaelApproved 5y ago

> We rolled, and it turned out fine. Who is “we”?

kortex 5y ago
Company I worked for. We built an aerial multispectral imaging system for monitoring seals, polar bears, and other mammal populations. It's 3 high power rugged PCs, semi-affixed in a shock mount case in the tail of a Twin Otter. There's no hangars available at the airbases in e.g. Kotzebue, Deadhorse, Utqiagvik, so it sits on the tarmac and experiences some intense temperature swings. It's made it 2 winters and dozens of missions so far. The customer is NOAA and they really don't have oodles of cash to spend on this thing, so it's mostly commodity hardware. Initially we designed this whole crazy insulated case to keep it from getting too cold, but the aircraft engineers nixed it due to fire hazards. The airframe isn't airtight so it gets most of the brunt of the diurnal swing.
- nr2x 5y ago
  Sounds like a fun job!
  - kortex 5y ago
    It was brilliant fun and also the most stressful period of my life, due to it being a bit far out of our core competencies at the time, delays in getting the camera hardware we had to interface with, limited staffing, and a comedy of other errors. Also the PM gets insanely airsick. As a result of all that, I got to go up to Kotzebue, AK with the PM to do the integration testing. So there I am, hacking like mad in a terminal in the back of this airplane over sea ice, trying to squash various bugs. I blame my love of travel and reading while flying for my resilience to motion sickness. Stressful AF. So worth it.

devit 5y ago

You could also add a heater.

duskwuff 5y ago
And, fwiw, that's exactly what SpaceX did to make Dishy tolerant of low temperatures (and to help it clear snow/ice from the dish). There's just no equivalent solution for high temperatures.
- zamadatix 5y ago
  I used to think it was just a matter of product cost to do active cooling... really the problem isn't the temperature it's the dew point! Which I guess could probably be solved with enough hardware, planning, and cost as well... but a ridiculous amount compared to adding an electric heater for the opposite problem. Come to think of it does anyone know of a consumer device that utilized active cooling (as in would get colder than ambient not just fans or whatnot)?
  - meimo 5y ago
    a fridge
    - zamadatix 5y ago
      I mean electronic device, things in a fridge/freezer generally don't mind condensation or deposition.
  - oceanswave 5y ago
    A pump, a home depot bucket in shade, some duct tape and tubing would probably be sufficient.
  - ficklepickle 5y ago
    Thermoelectric coolers can cool below ambient. You can get them for CPUs, I saw one on a Linus YouTube video. https://en.wikipedia.org/wiki/Thermoelectric_cooling https://en.wikipedia.org/wiki/Thermoelectric_cooling

eyegor 5y ago

Along the same lines, most hardware is designed under the assumption that you aren't significantly above sea level. Tons of medium-high voltage electronics have trouble with arcing once it turns on at 6000+ ft.

c_o_n_v_e_x 5y ago
Considering most of humanity lives within an hour's drive of the ocean, it's not a bad assumption.
- cheschire 5y ago
  I'm interested why you are being downvoted, as you bring up a good point that aligns with what kortex was saying in their post. edit: ahh, now I see it's because you're factually incorrect. It's only 1/3rd of humans that live within 100km of oceanic coasts. https://science.nasa.gov/earth-science/oceanography/living-ocean/ https://science.nasa.gov/earth-science/oceanography/living-o...
gugagore 5y ago
arcing involves ionizing air, right? I would have expected that the breakdown voltage of air increases with altitude, due to decreasing density of air.
- kalnins 5y ago
  I would guess that it could be due to having more ions in air due to higher radiation levels.
- labawi 5y ago
  It's actually the opposite (to a point, I think). Higher mean free path means more time to accelerate, then hit and ionize something else. That's how fluorescent tubes maintain discharge a meter long at measly voltages. Radiation doesn't help either, as sibling commented - it creates ions making the initial breakdown easier, though it shouldn't make a difference for a continuous flow that involves innumerable ions.

c_o_n_v_e_x 5y ago

Wide temperature (-40C to +85C) DIMM and SSDs are available.. Companies like ATP and Apacer carry them. Intel's Xeon D series are meant for wide temps.

coolspot 5y ago
-40C is very close to 0F (-32C) claimed above. Update: -40F is -40C, oops, my bad, I don’t understand Fahrenheit. ¯\_(ツ)_/¯
- tedunangst 5y ago
  Um, -40C is -40F.
- barko 5y ago
  -40° Celsius is actually equal to -40° Fahrenheit, it's the temperature at which the two meet. 0° Fahrenheit is about -18° Celsius, did you perhaps multiply 0 by 5/9 then subtract 32 instead of the other way around?
tigershark 5y ago
The starlink dish is rated to -30C so it’s not that bad on the freezing side.

fnord77 5y ago

I wouldn't want to roll the dice when it comes to aircraft

kortex 5y ago
The hardware is an imaging system (see other comment). It does not impact flight avionics in any way, and is on an isolated power source. The flight engineers wouldn't let us roll the dice on anything mission critical. They did make us redo a bunch of wiring harnesses to use non-smoke-producing wires, for example.

systemvoltage 5y ago

"Hardware is hard", I would say Manufacturing is hard.

double0jimb0 5y ago

That expensive part is NRE and only making a few tens of them, no production efficiency. With the volumes spacex will be hitting, efficiencies will certainly be found and NRE exceptionally better amortized.

foobiekr 5y ago

No, it’s not. Ignoring perfectly predictable issues because you can’t even learn from recent history (millions of sat tv dishes in the nineties) or from industry (literally millions of cellular antennas) is not “smart.” Also your example is a poor one. Engineering a systems solution for 0F is far easier than engineering for outdoors in the sun. Heat removal is a primary consideration and a 0F environment makes that far easier. In 0F your issue isn’t the cold, it’s the lack of humidity - again, something everyone who has more than two years in HW knows.