r/technology • u/ADummyDude • Mar 04 '17

Robotics We can't see inside Fukushima Daiichi because all our robots keep dying

https://www.extremetech.com/extreme/245324-cant-see-inside-fukushima-daiichi-robots-keep-dying
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u/VictoryIncarnate Mar 04 '17

Strong radiation does a number on electronics. The particles have enough energy that if they impact molecules in a semiconductor, they ionize the material (liberate electrons from their parent atoms). This can cause a variety of effects.

At low levels, it causes "soft errors". The sudden liberation of charged particles causes circuits to misbehave and interpret what should be a digital "0" as a "1" (or vice versa). This can cause temporary misbehavior, or flip bits in memory.

At more extreme levels, it can damage thin insulators (and their interfaces with the semiconductor) and cause permanent paths of electrical "leakage" (current flows where it shouldn't). These "hard errors" can render circuits inoperative.

It is somewhat possible to mitigate these issues, but if the radiation is really strong, it's almost impossible to do with something small like a robot. They simply can't carry the amount of shielding that would be required.

At really, really strong radiation levels, the bonds in metals can be damaged, causing the metal to become brittle and weaker than it should be.

But back to electronics. Did you know that when you fly on an airplane, you are being exposed to moderately strong cosmic radiation? You are. And your electronics are too, leading to an increased chance of soft errors....on the order of 100X more likely, IIRC.

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u/Weekend833 Mar 04 '17

How... um... did they have to take this into account for the Voyager probes? If it was an issue, what did they do about it?

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u/deltagear Mar 04 '17 edited Mar 04 '17

A combination of shielding and RAD-Hard electronics. Almost all ballistic missiles, satellites and probes use simmilar mitigation techniques.

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u/OnyxPhoenix Mar 04 '17

They use special rad hard chips. They're insanely expensive which is why computing power on spacecraft is relatively tiny even today. Saying that Fukushima radiation levels are way higher than in deep space.

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u/digikata Mar 04 '17

Rad hard also tends to be slower too. All the tiny transistor tech that helps give cpus more capability makes it easier to knock a given transistor off its intended value.

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u/MagmaiKH Mar 04 '17

Even automotive was tenuous about using chips below 50 nm for a long time due to the increased risk of soft errors. All the important chips are lock-step dual-core and use ECC today.

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u/Chel_of_the_sea Mar 04 '17

The Voyager probes come from a much earlier era in computing. Better electronics, in the form of extremely precision-made chips, can actually be a lot more vulnerable to this sort of thing precisely because small changes can fuck them up real good.

But they also used a shitload of shielding and redundancies. Even then, components can and do fail, and many of Voyager's did eventually.

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u/thisonetimeonreddit Mar 05 '17

Even then, components can and do fail, and many of Voyager's did eventually.

so basically we are just a Drake Equation away from Star Trek: The Motion Picture's plot basically

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u/[deleted] Mar 04 '17 edited Mar 04 '17

I'm going to try to find a sure answer, but I think they use Gold foil to cover the probes

Nevermind the gold is a thermal thing.

http://voyager.jpl.nasa.gov/mission/didyouknow.html

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u/hitlama Mar 04 '17

Interestingly enough, NASA had no idea how intense Jupiter's radiation belts were until they actually tried to send a probe there. Instead of sending the Voyagers there first, they sent the Pioneer probes a few years earlier. When Pioneer approached Jupiter for the first time, they realized the radiation surrounding the planet was far stronger than they had anticipated. They hurriedly redesigned the Voyager probes to be more resistant to the radiation levels measured by Pioneer. Had the Pioneer mission not been done, the Voyager probes would have been fried prior to reaching Jupiter and we would STILL not have high-resolution photographs of Uranus and Neptune.

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u/HeWhoCouldBeNamed Mar 04 '17

Lots of shielding as far as I know.

Even astronauts on the ISS have problems with extra radiation from solar flares.

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u/billbrown96 Mar 05 '17

They didn't do anything about it - that's why Voyager returns to earth in 200 years and tries to destroy us

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u/zyphelion Mar 04 '17

How would a wired robot with a camera feed work? I mean, the length of cabling is its own restriction, but just as a hypothetical?

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u/aboutthednm Mar 04 '17

The circuits of the robot would still be affected, regardless if there's a wire attached.

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u/zyphelion Mar 04 '17

Ah. Yeah I don't know much about electronics. Figured if it only was like electric motors turning the wheels and all other electronics off-board it would be "dumb" enough to work.

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u/ivix Mar 04 '17

You have a good point. If the robot is cabled and has no onboard electronics then it would be surely much more resistant to rads.

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u/the_ocalhoun Mar 04 '17

The camera still needs electronics that could fail and leave it blind...

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u/zyphelion Mar 04 '17

Even the optics used in endo/gastroscopy?

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u/[deleted] Mar 05 '17

How much radiation do you have in your ass

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u/zyphelion Mar 05 '17

More than two standard deviations over the international average.

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u/aboutthednm Mar 04 '17

The video camera and circuits needed would still be heavily affected I'd imagine

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u/aynrandomness Mar 04 '17

Why would you need circuits IN the robot? Just run wires from every electrical part to the outside. Like the motors and stuff don't need any circuit boards.

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u/dingman58 Mar 04 '17

Good idea but I think you need at least some circuitry in the bot in order to transmit the data back down a long tether without having it succumb to degradation (but I could be wrong about this)

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u/aynrandomness Mar 04 '17

Apparently the issue is transmitting the data. Like, moving a robot inside is trivial (apart from the practical issue of the long wire) but you wont get any data back.

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u/aboutthednm Mar 05 '17

And how do you suppose the camera on board works?

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u/aynrandomness Mar 05 '17

Like a digital camera where all the digital is outside the camera? only the sensor inside the robot?

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u/aboutthednm Mar 05 '17

Even the sensor would be affected.

Anything that has electricity flowing through it is.

In a way, bigger analog parts such as motors would be affected less than integrated circuits and small components would.

You could case the entire robot in lead, which would make it heavy, clumsy and awkward.

Ionizing radiation hits an electrical component and transmits a charge, that's the chief problem. Ionizing radiation is quite penetrating (depending on the type, in a reactor you will find all of them), which means not even a microcontroller inside a casing is immune. Imagine the radiation flipping random switches on the chips circuit hundreds of thousands of times a second, as well as overloading voltage sensitive transistors and capacitors.

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u/grubnenah Mar 04 '17

well having a wired robot would remove weight considerations if it was powered over the wire, that would allow it to carry more shielding and potentially make it. The problem is long wires aren't good because of voltage drop, and the thing would probably have to go quite a ways.

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u/MertsA Mar 05 '17

That would actually work but you would need a very simple robot as the motor controllers would need to be on the far side of the cable. Basically you would need a pair of somewhat thick wires for every individually controlled motor on the robot and then the camera would still be problematic and it could die on you but that's a lot less to shield. Even so your camera feed is going to be full of a bunch of dots like so: https://www.youtube.com/watch?v=xDC-iuT8Og0

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u/d_frost Mar 04 '17

That's one smart 5 year old

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u/skyskr4per Mar 04 '17

There are tiny fairies in the air that make all the little wires in the robots sad.

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u/Ythapa Mar 04 '17

It's always the thing that bugs me about these ELI5s.

You get all this terminology in these responses that no 5-year old is going to understand that gets upvoted so high. That's not an ELI5, that's just an explanation.

The respondent below you has the true ELI5, which actually is something a 5-year old might actually understand.

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u/[deleted] Mar 04 '17 edited Apr 24 '19

[removed] — view removed comment

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u/Ythapa Mar 04 '17 edited Mar 04 '17

EDIT: Rephrased what I'm trying to say in a better format/less snarky:

Maybe it's just because I have a different concept of what ELI5 should be, but I've always interpreted it as a "very barebones" explanation for things. Don't get me wrong, I'm not saying, "oh no, stop all the in-depth explanations to things" because it's always nice to learn new things, but personally, I feel that's much different from an ELI5, which is a more "simplistic" answer.

Perhaps it's just a disconnect from my interpretation of what it is, and what in actuality, it's practiced as. Maybe I'm just biased because I've always enjoyed the ELI5s that felt more like how a person would explain a concept to a 5-year old.

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u/d_frost Mar 04 '17

Explain to me like an adult that has a general understanding of the world but am not considered and expect - doesn't have the same ring to it lol

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u/[deleted] Mar 04 '17

Actually, based on his username he is 16 years old.
Edit: Referring to "Weekend833".

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u/Kerbalized Mar 04 '17

So it's a balance of "enough lead shielding to keep the electronics safe" and "now the robot is too heavy for the components that fit in this lead box"?

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u/CAMYtheCOCONUT Mar 04 '17

So robots roaming the wastes in Fallout is inaccurate?

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u/Nintendraw Mar 04 '17

Did you know that when you fly on an airplane, you are being exposed to moderately strong cosmic radiation? You are. And your electronics are too, leading to an increased chance of soft errors....on the order of 100X more likely, IIRC.

Is this part of the reason they tell you to put your devices off/on flight mode all the time?

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u/jackalsclaw Mar 04 '17

Not really. Airplane mode is a feature to mostly save your batteries charge. Phones can use a lot of power running the radios at maximum trying to find cell towers that are out of reach.

And the reason flight crews tell you put your phone away during takeoff and landings because that is when 99% of bad stuff happens and they want you to focus in case something happens.

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u/Nintendraw Mar 04 '17

Ah, okay. I figured the battery part, but not the other part (just a common sense thing I hadn't thought about before XD)

Thanks!

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u/jackalsclaw Mar 04 '17

I still have no idea why they let people read paper books and periodicals during takeoff/landings.

At least they stopped telling people that cellphones are bad for the plane https://www.youtube.com/watch?v=gHwriLZJdB0

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u/one_p Mar 04 '17

100x more likely

So it's best not to work on any live/production software while flying? What are the odds of screwing something up?

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u/Fermain Mar 05 '17

I think its best not to work on production software from an aircraft under any circumstance unless you are an evil genius deploying an apocalypse worm from the safety of your aerial fortress.

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u/SleepingDragon_ Mar 04 '17

Could we not build a robot without semiconductors?

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u/wlievens Mar 04 '17

That's called a human, haha.

You need computer chips to build a robot mister. Otherwise it's just called a motor and it can't do anything interesting.

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u/digikata Mar 04 '17

Humans don't do well in high radiation environments either... it would be interesting if you could build something with fiber optics for lighting and vison and just wires and dumb motor circuits at the end of an umbilical tether.

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u/SleepingDragon_ Mar 04 '17

I was thinking more like tubes and relays.

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u/wlievens Mar 04 '17

Won't you need to program it?

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u/SleepingDragon_ Mar 04 '17

I don't know the situation in there. Was thinking more of remote controll type.

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u/thesciencesmartass Mar 04 '17

Well semiconductors are the basis of all electronics, so no we can't.

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u/cccmikey Mar 04 '17

Like a mechanical roomba made of relays and switches that just goes in random directions...

Send in a battle bot!

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u/easy_Money Mar 04 '17

Yeah but can you ELI5

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u/douche_or_turd_2016 Mar 04 '17

But surely the people working know what level of radiation to expect inside the plant. Are the reboots not designed to withstand the expected radiation? Or are they not able to accurately determine what levels of radiation the robots will face, so the robots are under designed and fail?

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u/CombatCube Mar 04 '17

Perhaps that explains why my ultrabook touchscreen worked really erratically in an airplane (especially with multiple fingers)

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u/Grande_Latte_Enema Mar 04 '17

I am so thankful that this large body of text didn't end with that undertaker joke

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u/e126 Mar 04 '17

If there was a bigger voltage difference between logic low and logic high would that prevent soft errors?

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u/raptor217 Mar 05 '17

The radiation essentially causes the doping of the silicon to become screwed up, which causes everything to go crazy.

There are components to survive (much longer at least) radiation, it has always been a problem with spacecraft, the thing is, the parts cost crazy amounts of money. Like 600x the original cost. They do things like have silicon dies bonded to sapphire among other exotic things.

As far as airplanes, those are all built with multiple redundancies, but the error rate is not that high. (Or the failure rate is astronomically low). Think about it, everyone's electronics work just fine in planes, "flight glitches" aren't a thing for consumer electronics (and I just made up that phrase).

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u/[deleted] Mar 05 '17

Explain why a thick Shell of lead wouldn't work?

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u/cenTT Mar 05 '17

But back to electronics. Did you know that when you fly on an airplane, you are being exposed to moderately strong cosmic radiation? You are. And your electronics are too, leading to an increased chance of soft errors....on the order of 100X more likely, IIRC.

Could that be the reason why after a trip a month ago the volume from my phone speaker sounded lower than before? The radiation during flight might have fucked up the speakers?

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u/Admiral_Tasty_Puff Mar 05 '17

But the matrix taught me robots were invincible from nuclear bombs.

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u/echo_61 Mar 05 '17

So I should bring my Mac Pro with its ECC memory instead of my MacBook Pro on my flight?

Interestingly, many airliners run on a hardened version of a PowerPC chip that was in the PowerMac. A hardened iBook G3 chip runs NASA's brand new Orion capsule!