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* Fiber cables (that OP and I wrote) means a cable made out of glass - no problem at all for radiation. (face palm #1) * You can transfer light through such ca

by frik 9y ago

* Fiber cables (that OP and I wrote) means a cable made out of glass - no problem at all for radiation. (face palm #1) * You can transfer light through such cables. This means you use one cable to send light into the scene and another cable to see to the scene. Please just look up how endoscopy works for many many many decades, long before computers were a thing. (face palm #2) You probably have a SPDIF connector at your home entertainment devices. Have a look at the fiber cable and hold it against a light or look through it, to get the idea. https://en.wikipedia.org/wiki/S/PDIF https://en.wikipedia.org/wiki/S/PDIF (it's about a single fiber cable, not a multi-fiber cable that is nowadays more common) * Endoscopes are operated with wires, mechanical wires operated by a human (or could be by low tech remote pneumatic construct many feets away from the scene) - just look up endoscop (face palm #3) So a low tech solution would work in such environments, though it's not as news worthy and not as cool as some robots, but it would be useful for a long time, not die at all. I am surprised by the lacking education here, unfortunately the site got mainstream and attracted average joes from everywhere - with even basic education like in physics and mechanical engineering we could have a proper conversation here. Even CS and startup topics are now littered by corporate drones and fanboys of minor things. Maybe different tags/channels would help to channel the news.

nate_meurer 9y ago
> "a cable made out of glass - no problem at all for radiation" I don't know where you got that idea, but it's very wrong. Optical glasses of all kinds are quite vulnerable to darkening, clouding, and embrittlement by much lower levels of ionizing radiation than those at Fukushima [0]. Even if you shielded the fibers with centimeters of lead, the radiation received along the fiber's length would quickly render it useless for either imaging or lighting. And with that much shielding, good luck moving it around. How exactly do you think you'll get your low-tech thingy into place, maneuvering it hundreds of meters of abandoned building, ruble and industrial wreckage? Remember that you can't even be in the parking lot unless you're in a heavily shielded truck. How would you protect the optical assemblies at the working end of your cable, which cannot be shielded and are thus exposed to hundreds of Sv/hr? Do you know how Toshiba designed the optics on their Scorpion robot? How would you improve on their materials or lens arrangements? Have you considered the thermal effects of this much radiation, which is capable of heating the internal elements of your assembly to hundreds of degrees? Read the links I gave, maybe do a bit of googling, and be assured that you have not actually outsmarted hundreds of nuclear physicists and robot experts with your super clever idea. 0: http://www.dtic.mil/dtic/tr/fulltext/u2/a013786.pdf http://www.dtic.mil/dtic/tr/fulltext/u2/a013786.pdf
- frik 9y ago
  Look at the OP news article, they took a picture - so they have already a transparent material (type of glass or plastic). There you go. My comment was about a low tech bigger scale endoscope instead of error prone high-tech robotics. And glass and probably types of plastics can be quite hardened against negative effects of radiation. Think of transparent windows where you can look at the reactor core of research reactors, NASA space missions with high precision optics that last for decades, etc. The issue in Japan is their culture, their problem with "loss of face" which inevitably caused problems in the hours when the worst case scenario unleashed - and the whole world watched 24h live while they did little and USA proposed (and had them ready on the nearby ship) to send in helicopters with backup generators but Japan made no official request for help - lesson learned, in the end US should have crossed their border and fixed the generators because Japan hasn't acted rational at all. Even the years later, they could have learned from Russia how to fix it quickly by sending in human people. But again false bride, and "loss of face" gets in their way. They keep going on with business as usual, and the leaks aren't fixed or anything worth mentioning. Chinese and Japanese have a related culture, yet Chinese know what they are doing and are very successful. "All optical fibers undergo some darkening depending on a number of factors that include: ionization type, optical fiber core glass composition, operating wavelength, dose rate, total accumulated dose, temperature and power propagating through the core. Since attenuation is composition dependent, it is observed that fibers having pure silica cores and fluorine down doped claddings are amongst the most radiation hard fibers. To minimize damage consequences, it is better to use a pure silica core fiber at higher operating wavelength, higher temperature (accelerated recovery) and higher signal power (photo-bleaching)." -- https://en.wikipedia.org/wiki/Radiation_effects_on_optical_fibers https://en.wikipedia.org/wiki/Radiation_effects_on_optical_f... -- (shortened snip)
  - nate_meurer 9y ago
    LOL, please show me an example of a "window where you can look at a reactor core". Show me a window protecting someone from thousands of rads/hr from an active reactor core. Please :) And no, the radiation seen in space exploration is not comparable to the levels at Fukushima. Not anywhere close. Have you ever actually seen an endoscope? Do you have any idea how complicated they are, how many optical elements they have and how precise the tolerances must be? Did your study of wikipedia reveal the extent of transmission loss in rad-hard optical materials after exposure to levels of radiation near those at Fukushima? Because the link I gave you does. Read that and tell me how long you expect your fiber optics to last down there. I'll give you a hint: not very long. Tell you what, just make a sketch of your "low-tech" endoscope that withstands hundreds of Sv/hr, deals with hundreds of degrees of internal heating, is waterproof of course, and is robust to extreme physical abuse. And then come up with a way to remotely maneuver it into place through hundreds of meters of industrial wreckage, without using a robot. Then get ready to be famous, for your brilliant low-tech solution will be lauded by the international team of scientists and engineers working on Fukushima who simply hadn't thought of it for over 6 years.

by frik 9y ago

nate_meurer 9y ago

> "a cable made out of glass - no problem at all for radiation" I don't know where you got that idea, but it's very wrong. Optical glasses of all kinds are quite vulnerable to darkening, clouding, and embrittlement by much lower levels of ionizing radiation than those at Fukushima [0]. Even if you shielded the fibers with centimeters of lead, the radiation received along the fiber's length would quickly render it useless for either imaging or lighting. And with that much shielding, good luck moving it around. How exactly do you think you'll get your low-tech thingy into place, maneuvering it hundreds of meters of abandoned building, ruble and industrial wreckage? Remember that you can't even be in the parking lot unless you're in a heavily shielded truck. How would you protect the optical assemblies at the working end of your cable, which cannot be shielded and are thus exposed to hundreds of Sv/hr? Do you know how Toshiba designed the optics on their Scorpion robot? How would you improve on their materials or lens arrangements? Have you considered the thermal effects of this much radiation, which is capable of heating the internal elements of your assembly to hundreds of degrees? Read the links I gave, maybe do a bit of googling, and be assured that you have not actually outsmarted hundreds of nuclear physicists and robot experts with your super clever idea. 0: http://www.dtic.mil/dtic/tr/fulltext/u2/a013786.pdf http://www.dtic.mil/dtic/tr/fulltext/u2/a013786.pdf

frik 9y ago
Look at the OP news article, they took a picture - so they have already a transparent material (type of glass or plastic). There you go. My comment was about a low tech bigger scale endoscope instead of error prone high-tech robotics. And glass and probably types of plastics can be quite hardened against negative effects of radiation. Think of transparent windows where you can look at the reactor core of research reactors, NASA space missions with high precision optics that last for decades, etc. The issue in Japan is their culture, their problem with "loss of face" which inevitably caused problems in the hours when the worst case scenario unleashed - and the whole world watched 24h live while they did little and USA proposed (and had them ready on the nearby ship) to send in helicopters with backup generators but Japan made no official request for help - lesson learned, in the end US should have crossed their border and fixed the generators because Japan hasn't acted rational at all. Even the years later, they could have learned from Russia how to fix it quickly by sending in human people. But again false bride, and "loss of face" gets in their way. They keep going on with business as usual, and the leaks aren't fixed or anything worth mentioning. Chinese and Japanese have a related culture, yet Chinese know what they are doing and are very successful. "All optical fibers undergo some darkening depending on a number of factors that include: ionization type, optical fiber core glass composition, operating wavelength, dose rate, total accumulated dose, temperature and power propagating through the core. Since attenuation is composition dependent, it is observed that fibers having pure silica cores and fluorine down doped claddings are amongst the most radiation hard fibers. To minimize damage consequences, it is better to use a pure silica core fiber at higher operating wavelength, higher temperature (accelerated recovery) and higher signal power (photo-bleaching)." -- https://en.wikipedia.org/wiki/Radiation_effects_on_optical_fibers https://en.wikipedia.org/wiki/Radiation_effects_on_optical_f... -- (shortened snip)
- nate_meurer 9y ago
  LOL, please show me an example of a "window where you can look at a reactor core". Show me a window protecting someone from thousands of rads/hr from an active reactor core. Please :) And no, the radiation seen in space exploration is not comparable to the levels at Fukushima. Not anywhere close. Have you ever actually seen an endoscope? Do you have any idea how complicated they are, how many optical elements they have and how precise the tolerances must be? Did your study of wikipedia reveal the extent of transmission loss in rad-hard optical materials after exposure to levels of radiation near those at Fukushima? Because the link I gave you does. Read that and tell me how long you expect your fiber optics to last down there. I'll give you a hint: not very long. Tell you what, just make a sketch of your "low-tech" endoscope that withstands hundreds of Sv/hr, deals with hundreds of degrees of internal heating, is waterproof of course, and is robust to extreme physical abuse. And then come up with a way to remotely maneuver it into place through hundreds of meters of industrial wreckage, without using a robot. Then get ready to be famous, for your brilliant low-tech solution will be lauded by the international team of scientists and engineers working on Fukushima who simply hadn't thought of it for over 6 years.