Robots used at Chernobyl and a very good film using actual footage of the site. - Page 1
Forum section: electronics / general

author: Fraser
author_rank: Super Contributor
timestamp: June 28, 2015, 05:47:23 pm
content: I was researching robots that have been used in challenging environments and came across those that had been deployed in the Chernobyl clean-up operations.I am interested in remote rovers used on the moon and saw a comment on a Wiki stating that the designers of a 1970's Russian Lunikhod Moon Rover had been brought out of retirement to quickly design and produce a vehicle that could help clean up the Chernobyl site. The Original Moon Rover design was modified and a robot built. It was named the STR-1. Its heritage is obvious. I attach pictures... you will see what I mean.I have worked with Ionising radiation for much of my career so I was interested in how the robots performed. In short, they didn't. All were defeated by the conditions at Chernobyl. Humans had to do the work......that still sends shivers down my spine.I stumbled upon an excellent short documentary that uses real footage of the robots and clean up works. The narration comes from a man who was working on the site.Well worth watching. It is a very powerful video. I learned just how awful the conditions on the ground really were for the robots and workers. Please watch it, the brave people who gave their lives deserve to be recognised, and it teaches us techs a thing or two about machinery Vs flesh and bone, its effectiveness and its weaknesses.Also of interest are the machinery and robot graveyardsand the Robot Museum at Chernobylhttp://io9.com/a-museum-of-robotic-equipment-used-during-the-chernobyl-512831778http://englishrussia.com/2013/06/11/exposition-of-the-robotized-equipment-in-chernobyl/Admission that robots could not handle the radiation and conditions at Chernobyl:http://www.the-scientist.com/?articles.view/articleNo/10861/title/Soviet-Official-Admits-That-Robots-Couldn-t-Handle-Chernobyl-Cleanup/As the documentary says, the Chernobyl accident has drifted into the mists of time and the brave who gave their lives have often been forgotten. I have no issue with Russia or its people but I do wonder how the West would have dealt with such a disaster. Would we have sent people to their almost certain deaths ? Radiation poisoning is not a pleasant death.I listened to the words of the Officer telling his soldiers that its was 'OK and clear' for work, when he knew this was not so, and it made me shiver.The narrator does not show any criticism of him however. He was as much a victim of the situation as the poor young soldiers he commanded. What else could he say to calm their nerves ? Poor sods.I was appalled to read that Government bureaucracy prevented Western Scientists providing state of the art robot technology for the clean-up. That is abuse of the international movement of technology regulations, and not what they were intended for.I hope that the world never has to witness a radiation disaster like Chernobyl again, but if we do, I also hope that all governments who can assist, do so. And those that need help, bury their pride and ask for it.Aurora

author: SeanB
author_rank: Super Contributor
timestamp: June 28, 2015, 07:37:06 pm
content: Soviets still can make a tethered robot for clearing up, as they still have the required designers who can make the magamps, tube based equipment and the other rad hard stuff. Biggest issue is the wimpy silicon devices that fail, a magamp will work till it arcs over, and tubes as well. You will need a tether and a lot of power, but that tech is easy, though the trailing cables will be a problem for smaller units.

author: nctnico
author_rank: Super Contributor
timestamp: June 28, 2015, 10:18:50 pm
content: You can put batteries on a vehicle and even with tubes it isn't impossible to make a remote controlled vehicle.

author: Fraser
author_rank: Super Contributor
timestamp: June 28, 2015, 10:36:19 pm
content: But with respect guys, this is what I was investigating....the Russians had a massive incentive to create such Robots, yet they failed, as did the units from other countries. It turned out that the combination of massive radiation levels, the need for decontamination of the robot with high pressure sprays, and the challenging terrain, all took their toll and they failed quickly.I know Russian ingenuity well from having lived there. If anyone could pull together an 'agricultural' technology robot, or one that had hardened control systems, I would expect it to be them. Most Russian engineers that I worked along side were very clever, resourceful, and believed in the KISS principle to ensure ease of maintenance. Russian designers have a extraordinary command of basic physics and how it may be used to meet their goals. It somehow just didn't work for them in Chernobyl's challenging conditionsI noted that the Russians also tried importing technology, but it is pretty obvious that the buyers had no clue what they were doing. Wrong (too low) radiation level specs, machines originally designed to work on the sea bed and machines that were far too reliant on technology for control and operation. Much was learnt from the Chernobyl incident. None of our modern clever EOD robots or larger remote controlled 'Rovers' would have coped with the radiation levels present in this scenario. I hope this has been noted and some more robust units are available for such decontamination and clean-up work these days.Aurora

author: ez24
author_rank: Super Contributor
timestamp: June 29, 2015, 03:24:49 am
content: Thanks AuroraI enjoyed the post

author: G7PSK
author_rank: Super Contributor
timestamp: June 29, 2015, 07:35:24 am
content: I think the main problem was the time that was available to source and or create robots for the clear up. Put it bluntly there was no time, the mess had to be cleaned up ASAP before much more radioactive muck got loose.The only equipment that was going to work in such conditions would be entirely hydraulic and pneumatic on tethers, large powers and robustness is required.One thought occurs to me drill a shaft underneath the reactor install a small atomic bomb such that the whole lot falls into the resulting hole and gets covered over, obviously the blast must not break through the surface but that has been done before in underground tests. It just needs to be such that the ground left cant support the weight of the structure above and caves in.

author: Rerouter
author_rank: Super Contributor
timestamp: June 29, 2015, 08:07:31 am
content: At the time i doubt anyone was thinking, lets set an atomic bomb off under our failed reactor

author: G7PSK
author_rank: Super Contributor
timestamp: June 29, 2015, 08:22:07 am
content: If the devise was deep enough there is very little surface disturbance,The trick would be getting it just right. Other means of undermining could be used including conventional tunnelling, but the faster such a site is buried the better. I think that all future reactors should be built inside mountains so that when they are finished with the whole lot can be sealed up for the next billion years while the mountain erodes away.

author: mikron
author_rank: Contributor
timestamp: June 29, 2015, 08:34:38 am
content: Vladimir Shevchenko, director of the film, ''Chernobyl: A Chronicle of Difficult Weeks,'' died one year later from an excessive dose of radiation.Source:http://www.nytimes.com/1987/05/30/world/a-soviet-film-maker-at-chernobyl-in-86-is-dead-of-radiation.html

author: Fraser
author_rank: Super Contributor
timestamp: June 29, 2015, 09:11:15 am
content: There were some very brave people working at the Chernobyl site after the accident. As stated in the short film, some did not wear their dosimeters to avoid being taken off of the job. They did not want their replacements to suffer their likely fate. Very brave indeed.Aurora

author: mikron
author_rank: Contributor
timestamp: June 29, 2015, 11:07:56 am
content: The long and saddening list of fatalities can be found on Wikipedia:https://en.wikipedia.org/wiki/Deaths_due_to_the_Chernobyl_disaster

author: VK5RC
author_rank: Unknown
timestamp: June 29, 2015, 12:02:48 pm
content: I believe many have died also from radiophobia, after suffering some radiation exposure resultant depression and alcoholism has killed many, perhaps even more than the radiation itself.As Japanese health and radiation specialist Shunichi Yamashita noted."We know from Chernobyl that the psychological consequences are enormous. Life expectancy of the evacuees dropped from 65 to 58 years -- not  because of cancer, but because of depression, alcoholism and suicide. Relocation is not easy, the stress is very big. We must not only track those problems, but also treat them. Otherwise people will feel they are just guinea pigs in our research."

author: daqq
author_rank: Super Contributor
timestamp: June 29, 2015, 12:53:23 pm
content: QuoteActually, there was a tunnel built under the reactor with the intent of installing a cooling device so that the molten core would not seep through and contaminate ground waters.

author: VK3DRB
author_rank: Super Contributor
timestamp: June 29, 2015, 01:10:49 pm
content: The real danger is how the ex-Soviet knuckle heads will handle the leakage from the Chernobyl sarcophagus in a couple of thousand years when no one will be able to read their warning messages. There is NO technology that can remove the danger and the radiation is accelerating the decay of concrete. Unless there is new technology found to clean up this fiasco even with within a few hundred years, Europe may well become uninhabitable.Also consider populations moving into the area when no-one can read. Thanks to the digital storage age, there might not be many records around in 2,000 years to say how toxic the region has become and why.

author: daqq
author_rank: Super Contributor
timestamp: June 29, 2015, 01:30:47 pm
content: QuoteBy that time the most of the nasty will have decayed on its own.

author: rolycat
author_rank: Super Contributor
timestamp: June 29, 2015, 02:02:36 pm
content: Quote from: VK3DRB on June 29, 2015, 01:10:49 pmHyperbole much?A new multinationally funded confinement structure is nearing completion, and is to be used as a framework for demolition of the old sarcophagus and eventually the reactor itself.Even if the sarcophagus collapses before the new enclosure is complete, serious contamination would mostly be confined to the exclusion zone.

author: nctnico
author_rank: Super Contributor
timestamp: June 29, 2015, 02:19:50 pm
content: Quote from: VK3DRB on June 29, 2015, 01:10:49 pmI think you have the wrong idea on how big Europe really is (nearly 40 times bigger than New Zealand and also bigger than the United States). They are currently building a new structure around the reactor but most of the really dangerous stuff is buried deep inside the reactor under lots of lead and other materials. That won't just get blown away by the wind.

author: Len
author_rank: Frequent Contributor
timestamp: June 29, 2015, 06:07:09 pm
content: Quote from: G7PSK on June 29, 2015, 08:22:07 amUnfortunately, a number of underground nuclear tests have failed to get it just right and spewed varying amounts of fallout into the surroundings. This technology isn't reliable enough to be used where you don't want more contamination.

author: rolycat
author_rank: Super Contributor
timestamp: June 29, 2015, 06:20:41 pm
content: Quote from: Len on June 29, 2015, 06:07:09 pmVery substantial amounts of fallout.As nasty as the Chernobyl disaster was, atomic weapons testing in the fifties and sixties released between 100 and 1000 times as much radioactive material into the atmosphere.[*]

author: Fraser
author_rank: Super Contributor
timestamp: June 29, 2015, 06:27:45 pm
content: I have just read up on the 2011 Fukushima Daiichi nuclear disaster...... I must have been asleep the past few years on that front......I had not realised just how serious that incident truly washttps://en.wikipedia.org/wiki/Fukushima_Daiichi_nuclear_disasterThe incident time line is very long but an interesting read. Its last entry is January 2015.https://en.wikipedia.org/wiki/Timeline_of_the_Fukushima_Daiichi_nuclear_disasterIts all a bit of a mess there and TEPCO have not helped matters at all. One mistake after another.It could so easily have been a multiple Chernobyl disasterI see that they have had robots working reliably inside highly contaminated environments within teh reactor buildings though. Some of the recorded levels would be lethal to humans..... with a 100% mortality rate. (even if suited in protective equipment).It will be many years before that site can be considered sorted.Aurora

author: SeanB
author_rank: Super Contributor
timestamp: June 29, 2015, 06:56:10 pm
content: Funny enough the Chernobyl exclusion zone is a thriving wildlife preserve, going back to a primary forest quite fast, now that there is no more clearing of trees. Have a look at the videos of the zone by Bionerd, where you can see how the area is recovering with only minor spots with higher levels of radiation. Just do not eat the fish in the cooling pond, they are both toxic from heavy metal but are also rather radioactive as well. You can eat the fruit from the trees, just not the mushrooms or a lot of the meat from wild animals.

author: Galenbo
author_rank: Super Contributor
timestamp: June 29, 2015, 07:05:40 pm
content: Quote from: SeanB on June 29, 2015, 06:56:10 pmThere was an interesting study, showing that all animals had a normal life expectancy now, but were radioactive.The only thing they coudn't/wouldn't measure is the number of ill/wrong-borns and how fast they die.Everything looks normal, except human presence.

author: daqq
author_rank: Super Contributor
timestamp: June 29, 2015, 07:18:55 pm
content: QuoteTo be fair tech has come a little way since 1986 - what would have been impossible a few decades ago is possible (albeit pricey) now. Both for power electronics as well as logic - you can get off the shelf-ish rad hard processors, or you can build a very small control system and shield the hell out of it. Still, the robots suffer and some just give up. Also, the Soviets of the time were improvising a lot of the stuff as they went on, exploring unknown territories.

author: helius
author_rank: Super Contributor
timestamp: June 29, 2015, 09:52:42 pm
content: Aurora: I view it as quite sensationalistic to portray the army conscripts being "sent to their deaths". They were working under great pressure with substandard safety equipment, and had little knowledge themselves of radiation dangers, but their exposure was limited to very brief periods, from 30 seconds to one minute before the worker was permanently discharged.Almost all of the casualties from the Chernobyl disaster were in the first days when the reactors were still burning. The events in that film were six months later, when the situation was stabilized and the cleanup and recovery were underway. In the narration he describes area M as "your thousand röntgens", which must be a translation error as the radioactivity on the roof was many times that. More likely he meant 1,000 rem/hr, or 10 Sv/hr, which is the level of exposure that can cause death in hours, therefore highly dangerous to workers. For the conscripts, their one-minute duty could expose them to 0.16 Sv, the same total dose of radiation that the astronauts on the One Year ISS mission will experience. There are some houses that expose their occupants to a higher dose every year.All of the deaths linked by real evidence to Chernobyl number about 80, including ~10 children who died from leukemia in the affected region. The number of deaths caused by the Fukushima disaster so far is zero. Many more people were negatively affected by depression and alcoholism brought on by fears of radiation: in the Wikipedia article linked several posts above,QuoteThe total release of carcinogens into the environment is also greater from fossil fuels than from all of the nuclear disasters. So you could say that Chernobyl (and now Fukushima) have caused greater numbers of cancers indirectly, by enabling Greenpeace to more effectively lobby against new nuclear power plants.

author: senso
author_rank: Frequent Contributor
timestamp: June 29, 2015, 09:54:21 pm
content: Here is my take on rad-hard robotics:They have a limited movement zone, so why dont they grab a gigantic mechanical diesel engine(no electronics to fry, just provide air and fuel and a hole for the smoke), they can even work under water), attach a pair of tankers for fuel autonomy, and an hydraulic or air pump/compressor.The robot is moved using hidraulic/pneumatic motors, and have linear pistons for moving arms, shovels, grabbers what ever.Throw in a couple pair of fiber optic bundles, some to pipe light in, the others to have image, it works for a endoscopy, it must work in a bit bigger scale.Hidraulic involves having hot fluids in a closed loop system, but with air there is no need to have a closed loop for control.I must be failing to grasp something, because I can't see any serious limitation, there are no electronics required, be it valves, germanium, silicone, GaAs or any exotic thing, plain old actuator(be they linear or rotary), the base station can be setup where there is less radiation so that it would work with either a cable or remote control.

author: mtdoc
author_rank: Super Contributor
timestamp: June 29, 2015, 10:26:14 pm
content: Quote from: helius on June 29, 2015, 09:52:42 pmNonsense. While the exact number of premature deaths due to Chernobyl cannot be known (due the population based epidemiology involved) - what is known is that the amount of radiation exposure that hundreds of thousands underwent will (and has) lead to many thousands of premature deaths.Even the widely acknowledged as way too conservative, Chernobyl Forum Report, put the number at 4000 (and was later updated to 9000). Other expert opinion has put it at many thousands more. No one credible believes it is only 80.Of course your other point about fossil fuel related carcinogens being of greater harm is true - at least in the short term. Given the slow decay of the isotopes in spent fuel rods it will be thousands of years before their potential harmful effects will no longer be a concern.

author: Fraser
author_rank: Super Contributor
timestamp: June 29, 2015, 10:54:42 pm
content: @helius,You are more than entitled to your view but I was not sensationalising the situation. It was bad, very bad. I presume you have read the causes of death for the people who died after being involved in the initial clean up. Do you really think that the three divers who went into the heavily radioactive water to open gates were unaware that it would cost them their lives ? Brave men indeed.A personal radiation Dosimeter is an interesting device. In a background radiation scenario it provides a decent 'whole body dose' indicator. It is less than reliable when you are standing on a roof with discrete radiation sources such as the lumps of highly radioactive graphite that the soldiers were dealing with. You could get irradiated in your lower body (nearest the source) and the dosimeter not capture the event.Did you see the face of the operation commander when the German robot failed. He knew the potential consequences of sending soldiers into that area. The soldiers commanding officer also knew the risk.The first thing I was taught as an NRPB safety officer was that "there is no safe dose of ionising radiation" It should be avoided whenever possible. Getting a years, or lifetime, dose of radiation in a few minutes or hours is not known to be a great idea.I trust that you will agree that Chernobyl witnessed many heroic and selfless acts by those involved. It will be very hard to apply statistics to the casualties that have occurred, and will occur, as a result of exposure to intense radiation sources, even if briefly. We still do not fully understand the mechanisms involved.Aurora

author: Someone
author_rank: Super Contributor
timestamp: June 29, 2015, 11:09:55 pm
content: Quote from: Aurora on June 29, 2015, 10:54:42 pmIts not known to be a bad idea either, the consensus is not even forming on the linear no-threshold model of human exposure to radiation. The UN is now backing a threshold model, and much more data is needed to fill in the gaps between natural background radiation levels and the extremes which have been tracked in individuals exposed in accidents.

author: Someone
author_rank: Super Contributor
timestamp: June 29, 2015, 11:23:10 pm
content: Quote from: helius on June 29, 2015, 09:52:42 pmPer unit of energy delivered, the current nuclear fleet is emitting (after inclusion of disasters) slightly more radiation than the current fleet of coal plants, but certainly not an order of magnitude more. Public exposure to radiation is very similar in both examples and hard to determine which is a greater source, but the public health outcomes are strongly in favour of nuclear as the other components of the emissions from coal power stations are full of nasties. Seems like it would be a good target for an info graphicThe secondary health impairment from fear and other ongoing psychological problems are real and only growing with the mass hysteria, just as with conventional fuels the nuclear industry needs more funding and research to progress but it may never advance further given how negatively it has been framed.

author: helius
author_rank: Super Contributor
timestamp: June 29, 2015, 11:39:26 pm
content: Yes, there is a strong human psychological component. The fear that people feel doesn't track with the actual risk, but with a number of factors relating to how unfamiliar is the risk, is it invisible, is there any way to personally mitigate the risk, does the risk affect people spread out or concentrated in one spot, and is there any moral component to being at risk.

author: mikron
author_rank: Contributor
timestamp: June 30, 2015, 07:35:17 am
content: There is a new Toshiba press release about the robot developed for investigations of the Fukushima containment:http://www.toshiba.co.jp/about/press/2015_06/pr3001.htmNot exactly hi-tec, is it?

author: mikron
author_rank: Contributor
timestamp: June 30, 2015, 08:21:15 am
content: Quote from: helius on June 29, 2015, 09:52:42 pmNonsense. This is the Cs-137 fingerprint left by the Chernoby disaster:The radionuclides released in 1986 can still easily be detected all over Europe. It is true that coal contains about 100 ppm of Uranium and hundreds of fossil powered plants have been operated here for over a century. But can you show me a similar map of Uranium distributions?By the way: Here is a map of deaths by cardiovascular deseases in 2000 :Source:https://jaymans.wordpress.com/2013/02/09/and-yet-another-tale-of-two-maps/This may of course all be pure coincidence... but there is some evidence that intake of Cs137 increases your risk of chronic and severe deseases (Source:http://www.smw.ch/docs/pdf200x/2004/49/smw-10219.pdf)

author: miguelvp
author_rank: Super Contributor
timestamp: June 30, 2015, 08:34:33 am
content: Wine loving countries versus beer/liquor loving countries.Yep I'll say coincidence.

author: mikron
author_rank: Contributor
timestamp: June 30, 2015, 08:42:31 am
content: We need to find a similar map from 1985.

author: Halcyon
author_rank: Unknown
timestamp: June 30, 2015, 09:09:59 am
content: Quote from: miguelvp on June 30, 2015, 08:34:33 amI think you're onto something there!

author: helius
author_rank: Super Contributor
timestamp: June 30, 2015, 09:13:39 pm
content: Inconveniently, Belgium is missing data on that map.And since when were Greece or Abruzzo known for their beer?I followed the link to the page it came from, which posits a completely different theory to explain the variation, by the way.That author suggests that the difference is racial in origin (different gene pools adapted to their local environments). In colder climates, calories from agriculture would be more scarce, and so the digestive system should adapt for greater efficiency. A more efficient gut leads to obesity or other metabolic problems.

author: miguelvp
author_rank: Super Contributor
timestamp: June 30, 2015, 09:39:39 pm
content: Quote from: helius on June 30, 2015, 09:13:39 pmmaybe theOuzoconsumption is not high enough to go red like on the other liquor loving countries, but maybe enough to change Greece to yellow like beer loving countriesHey I'm kind of making it up, because your know, there are lies and then statistics.

author: Towger
author_rank: Super Contributor
timestamp: June 30, 2015, 09:55:44 pm
content: Back in 1986 I spend a very wet easter week camping with the scouts in the rain. Radioactive rain...At least it was not black rain.

author: Someone
author_rank: Super Contributor
timestamp: July 01, 2015, 12:00:29 am
content: Quote from: mikron on June 30, 2015, 08:21:15 amYou can narrow the discussion down to a particular emission, or look at the wider effects of as many aspects of power generation as feasible. Thankfully this has been done numerous times so perhaps an EC report might be worth reading:http://www.externe.info/externe_2006/expoltec.pdfQuote from: mikron on June 30, 2015, 08:21:15 amFrance, Spain, Norway, Sweden (compare these last two to Finland), all having high proportions of Nuclear or renewable generation. The outliers I can see are the Netherlands and Italy.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: July 01, 2015, 02:18:37 am
content: Quote from: Aurora on June 28, 2015, 05:47:23 pmThanks. Powerful.Regarding technology: it's an interesting problem. Such levels of radiation will saturate any semiconductor, just as a xenon flash will disrupt solder-bump type chips. Rad-hard helps, but I don't think that's good enough at this level.Vacuum tubes might not even work; the glass will afford some shielding, but will also spit out lots of free electrons or ionization. Gas tubes (e.g., thyratrons, important for motor switching applications) might never turn off!Electromechanical designs (only switches, relays and motors) are probably the only thing really safe. (Magamps still require diodes, so aren't impervious -- though the active amplification should still be usable to far higher fluxes than general semiconductors are.)If nothing else, the materials themselves will eventually be affected (though, I think, this should be on the scale of days to months of exposure to those conditions). Atoms in solid metals are knocked out of place, leading to weakening, embrittlement, creep or expansion, and chemical changes in polymers (destruction and rearrangement of bonds). So the insulation in the windings, even Kapton, will eventually be cooked in-situ, and everything shorts out. (Windings made with mica sheets for insulation would probably last quite well, and could operate at very high service temperatures too, perhaps high enough to anneal the damage as it occurs. But man, it would be hard to successfully wind a motor that way.)Hmm, heavy motors and transformers and such might be self shielding well enough; perhaps it would be reasonable to hide the control electronics inside them? Ah, but internal magnetic fields mean problems from Hall effect. Otherwise, how much lead plate would it take? Probably not much more than a few cm, but man..Tim

author: mtdoc
author_rank: Super Contributor
timestamp: July 01, 2015, 02:43:08 am
content: Bionerd23 had several cool Chernobyl videos onher YouTube channel. She does some crazy (and illegal) exploring of the closed off site.

author: TerraHertz
author_rank: Super Contributor
timestamp: July 01, 2015, 11:14:39 am
content: Aurora, thanks for posting the Chernobyl 3828 video. It's very moving.For a more harrowing kind of moving, google children of Chernobyl.Everyone in favor of continued use of nuclear fission power and weapons programs should be forced to go and work in such hospitals and orphanages. Also to answer: "what happens to all the nuke plants along coastlines, if there's a small asteroid strike in the ocean?" The tsunami won't kill the planet, but a few dozen nuke plants smeared across the countryside would. For thousands of years.A few more links:http://everist.org/archives/links/__Chernobyl_links.txtAnd an intriguing thought:http://everist.org/archives/links/__Chernobyl_woodpecker_article.txtQuote from: Aurora on June 29, 2015, 06:27:45 pmHow on Earth did you miss that? Or that it's not at all 'sorted'? If anything it's far worse than Chernobyl, since there are 3 cores melted into the ground, right next to the ocean, in the basements of buildings fractured by earth movements. With a main stormwater channel actually running under and through the site, exiting into the cooling water channels, that empty into the sea.You might find these interesting:http://everist.org/Fukushima/20120430_Message_of_Fuku3.htmhttp://everist.org/Fukushima/comparison_preview6.png(I never finished that graphic. But it's still useful.)http://everist.org/archives/links/__Fukushima_nuclear_disaster_info.txtOh, also that Elena Filatova (Kid of Speed, see the Chernobyl links list) has a great collection of Chernobyl photos and videos available. I have a copy, well worth it. Not sure if she's still selling them.

author: Fraser
author_rank: Super Contributor
timestamp: July 01, 2015, 11:29:11 am
content: @T3sl4co1lThanks for the excellent comments. This exactly the sort of comment that I needed to understand some of the issues facing the robot designers.When dealing with such high levels of radiation it appears the rule book on hardware design is re-written. When the radiation starts to literally rip the structures of components apart at the atomic level the designer is placed in a very challenging position. Screening using lead can attenuate radiation levels but the thickness required means a lot of added weight and so the transport mechanisms have to be upgraded to support the added weight. Very quickly a useful, highly manoeuvrable robot becomes a lumbering, very heavy, machine that cannot enter areas that have low floor loading limits.Certainly a challenging design piece requiring knowledge of atomic level issues that may seriously effect operation and operation life. Such large levels of radiation are thankfully rare outside of the containment of a Reactor, but this means designers have to rely upon knowledge obtained during past nuclear explosions and accidents such as Chernobyl. Its when you look at the reports on radiation related accidents around the word that you realise how little we know about working with it in emergencies. Thankfully such accidents are rare but that is, in itself, the reason for mankind's non familiarity with the challenges that come to bear when it all goes wrong.I am not for a minute saying that scientists do not understand Nuclear Physics. What I am suggesting is that mankind still may not be that well equipped for cleaning up the mess after a serious nuclear accident involving very high levels of radiation.Thanks for the comments guys. Its been interesting.Aurora

author: Fraser
author_rank: Super Contributor
timestamp: July 01, 2015, 11:45:41 am
content: @TerraHertz,Sadly I have been suffering serious illness since 2010 so I must have been focussing on other matters. I was amazed that I had missed the seriousness of the situation as well ! As you say, it is nowhere near 'sorted' and I was less than impressed with how the response to the situation played out.Granted this happened as a result of a natural disaster but once the Genie was out of the bottle, they had one heck of a job to contain it. The safety systems were all seriously compromised by the natural disaster but surely designers of Reactors plants should consider the 'last ditch' situation where all systems are off line and it is necessary to kill the reactor, followed by cooling that is so resilient that a meltdown can be averted. It would appear that we live in a world that runs reactors on the 'it will never happen to me' mentalityWhen it all goes wrong and involves a Nuclear Reactor though, we all suffer. It feels like children playing with matches without an adult, bucket of water and first aid kit handy ! As we have seen in Japan, A SCRAM does not make the problem go away. You still have to cool the core.And I am not even anti-nuclear.Aurora

author: Fraser
author_rank: Super Contributor
timestamp: July 01, 2015, 12:05:38 pm
content: @mtdoc,Bionerd23 seems a very interesting lass. I was not previously aware of her significant number of videos on Chernobyl.http://www.atlasobscura.com/articles/the-woman-who-ate-chernobyl-s-applesCertainly not afraid of radiation ! I have no problems with her exploring Chernobyl. She gives us an insight that would otherwise not be available to us. My only concern is that she is female and I sincerely hope that nothing she does affects her ability to have healthy children, if that is ever her desire.In our youth many of us do dangerous things. They do not normally affect our later life significantly though. Women and radiation can be a more complex situation though.Brave lass all the sameSaying that, she knows the risks and see what happens when she is faced with an unpredictable danger.......a possibly rabid fox.Her girly side comes out.Aurora

author: rolycat
author_rank: Super Contributor
timestamp: July 01, 2015, 12:34:02 pm
content: Quote from: Aurora on July 01, 2015, 11:45:41 amPerhaps you were digesting therevelationthe day before the Fukushima disaster that the PWR2 reactors in the United Kingdom's nuclear submarines have a similarly flawed design. They share a dependence on active power for cooling and are "potentially vulnerable" to fatal nuclear accidents.Fortunately the new PWR3 design does not have the same flaws. Unfortunately they are busy fitting PWR2 reactors in all of the newAstute-class submarines.

author: amyk
author_rank: Super Contributor
timestamp: July 01, 2015, 01:39:15 pm
content: Quote from: T3sl4co1l on July 01, 2015, 02:18:37 amHydraulics and pneumatics would probably also work.

author: senso
author_rank: Frequent Contributor
timestamp: July 01, 2015, 02:44:08 pm
content: Why is there the need to use anything even electrical in such a specific use case robot?Its not like its a self driving bot, they are pretty much a glorified excavator/bulldozer, so my post in page 2, I asked why hydraulics/pneumatics don't work for such use cases.

author: daqq
author_rank: Super Contributor
timestamp: July 01, 2015, 02:48:11 pm
content: QuoteRemote control, visual feedback. Doing such stuff without some kind of electronics isn't easy. And cables/tubes leading to a robot are clunky - the point of this is to go through debris and cluttered zones - you're bound to get your cables stuck somewhere - just try going around your flat through every corridor while dragging cable behind you.

author: LabSpokane
author_rank: Super Contributor
timestamp: July 01, 2015, 03:40:27 pm
content: Aurora,Are you researching this for personal interest or for actual development? If it is the latter, we have a couple of nuclear laboratories in the northwestern US that *might* be able to assist you with the radiation exposure part of testing.Thanks for posting the videos. I watched the first and it was very powerful.

author: Fraser
author_rank: Super Contributor
timestamp: July 01, 2015, 05:03:57 pm
content: @LabSpokane,Thanks for the offer of help.This all came out of my long term interest in Lunar exploration probes/rovers and their beautiful designs. I am very much a fan of the Russian Lunokhod 'Moon Walker' probe.I was doing some more reading on the Lunokhod robotic probe and noted that the designers had been brought out of retirement to design robots for the Chernobyl clean-up. That incident presented the designers with a unique set of challenges and my research led to the film that I referenced in the original Post in this thread. The film was powerful viewing and I thought other members of this forum might like to see it. As you will see from my slightly defensive posts earlier, I have a great deal of respect for all who were involved in that clean up operation. I only wish that the robots had managed to do more of the work and so reduce the need for so many 'Liquidators' to work in close proximity to radiation contaminated materials.My interest is mainly robots and data collection systems used in space, but Chernobyl was certainly another very hostile and challenging environment for robotic systems.Thanks again for the offer, but this is just an interest of mine rather than anything that will lead to better robot designs. I will leave that to those who are expert in the field. Some of the battle bot designers may even go on to help develop more agile and robust vehicles for the benefit of mankind ?Best WishesAurora

author: T3sl4co1l
author_rank: Super Contributor
timestamp: July 01, 2015, 06:37:25 pm
content: Quote from: TerraHertz on July 01, 2015, 11:14:39 amI'm not clear on how much material was (is being) released -- the figures seem to be on the same order of magnitude (100s of PBq), but despite the accident being literally three times larger, there's still more containment of it. The pressure vessels didn't explode reactor contents, but they are leaking primary coolant, which after a meltdown, is carrying lots of soluble elements, most importantly iodine and cesium (which are also some of the hottest byproducts).Drainage through and over the site is drawing these elements into the ocean, so the local area remains contaminated. But the ocean is quite vast, and these elements are diluted very quickly as they travel. Yes, they are detectable on the US coast; but the detectable threshold is quite many orders of magnitude from the "least concern" level.And no, you can't do that very often, that is, dumping reactors into the ocean. But there is a very real and practical flow that is permissible. If coastal Level 7 events occur about every 30 years, there will be an average flow into the ocean while it decays (since the half lives of Cs134 and 137 are on that order), leading to a low average or equilibrium concentration.The other part is, strongly radioactive moderator (graphite blocks) wasn't strewn over the countryside (where it sits, rather than being diluted in the ocean). So the exclusion zone is smaller.Quote from: Aurora on July 01, 2015, 11:29:11 amI would love for there to be more education over nuclear power. The number one top fear is "ZOMG fallout". But it shouldn't be feared, nothing should. Understanding and respect are needed.Release of radioactive gas is a small and local hazard (it dilutes very quickly in the atmosphere, and decays fairly quickly; Kr85 being the longest at 10 years). Example: they did the right thing at TMI, because buildup of explosive gas could've made an inland Fukushima.Release of soluble elements (like iodine and cesium) into the ocean isn't a big deal (but certainly, best avoided). Terrestrially, they contribute to fallout and possible groundwater contamination (Sr90 and Cs137 are the dominant soil contaminants in the Chernobyl exclusion zone). Same goes for usually insoluble, but potentially mobile, elements (Sr, U, Pu..).Radiation itself isn't a big deal, as far as exposure. Understanding dose rate (and bodily location) is key. Chronic is worse than acute. If you can get into and away from it, the one-time dose can be quite high, while being at little risk for bodily damage or cancer. If you must live with it, you'll be orders of magnitude more sensitive, and have a cancer risk.Radiation isn't "in the air". You can breathe perfectly fine around it; but as soon as you kick up some contaminated dust, you have big problems. Dust sticks to lungs, skin, clothing, everything. This is why the exclusion zone was quickly (within months) churned and buried over: to lock the dust beneath the surface. And why the remains of these disasters are a continued risk, both in storage, and in their eventual decommissioning.Nuclear power can absolutely be operated in a safe, reliable and cheap manner; the problem is always the same with anything -- the human element. Incompetent design, operation or maintenance has been the central thread through all major disasters, regardless of their medium. Nuclear is no more dangerous than a chemical plant, and (comparing worst to worst, I would argue) less dangerous than a hydro dam. I would love to see some of the newer approaches developed and proven out; in the gray days since nuclear's prime, much thought has gone into the subject, making it potentially as safe as possible.Tim

author: apis
author_rank: Super Contributor
timestamp: July 12, 2015, 09:54:42 pm
content: Quote from: mojo-chan on July 02, 2015, 09:12:14 amPart of the problem is thinking all nuclear power plants are the same, they are not. Chernobyl was a disaster waiting to happen. The outer reactor building was supposed to be concrete but was woodit was a graphite moderated reactor and the emergency moderator rods were not designed correctly, so they failed to engage because of the heat...Fukushima was very different, caused by a extremely powerful tsunami. The reactor meltdown should be put into perspective of that imo.So main point is that there are safe nuclear and unsafe nuclear reactors. I'm in favour of safe nuclear, but strongly against unsafe.You also have to compare with the alternatives. Coal is worse in practically every aspect, it's just more popular because it's cheaper and easier and something familiar. Badly constructed hydro dams are much more dangerous, being the cause of the worst man made accidents (with the most human casualties).And it's worth to keep in mind that casualty figures from Chernobyl are based on models that are conservative in the sense that they are likely over estimates. Fatalities that can be linked directly to the accident is less than 100 IIRC.EDIT:I also heard on radio a few weeks ago that recent study estimate 3000 premature deaths yearly, caused by emissions from domestic wood stoves. In Sweden. Hopefully puts things in perspective...

author: Mechanical Menace
author_rank: Super Contributor
timestamp: July 13, 2015, 10:38:01 am
content: Quote from: apis on July 12, 2015, 09:54:42 pmBurning wood may be OK for the environment, but the fumes are terrible for your health. It's healthier to smoke a cigarette than be near an open wood fire.

author: apis
author_rank: Super Contributor
timestamp: July 13, 2015, 07:05:52 pm
content: Quote from: mojo-chan on July 13, 2015, 08:39:44 amOk. I haven't had the time to find out exactly what happened yet, I figured I would wait a few years until people have had time to analyse it fully and the lasting effects are more evident. But I don't think it makes sense to look at it as an isolated event, it was small part of a major natural catastrophe.Quote from: mojo-chan on July 13, 2015, 08:39:44 amSure, but then you should apply the same reasoning to hydroelectric and coal (and wood stoves apparently). If you pick safe, modern reactor designs and compare with the alternative, the most likely being coal or gas, nuclear is better in almost every aspect. Solar is great but can't completely replace coal/nuclear yet.Quote from: Mechanical Menace on July 13, 2015, 10:38:01 amYeah, apparently domestic wood stoves are a major health problem in suburban areas here. But for some reason people aren't as afraid of low tech as they are of high tech stuff.

author: mtdoc
author_rank: Super Contributor
timestamp: July 13, 2015, 07:28:08 pm
content: Part of the problem with nuclear power IMO is that it presupposes a stable, technologically advanced, civilization persisting, uninterrupted, for thousands of years in order to maintain reactors (including containing damaged ones like Chernobyl) and their spent fuel rods.History shows this to be extremely unlikely. Unfortunately few living now can imagine that our current civilization and technological sophistication will not continue indefinitely, just as few Romans, Ancient Persians, Ancient Chinese, etc could not imagine such during their historical periods of ascendancy.

author: apis
author_rank: Super Contributor
timestamp: July 13, 2015, 08:27:50 pm
content: Quote from: mtdoc on July 13, 2015, 07:28:08 pmYes, that is a good point. At the same time the idea that nuclear waste is extremely dangerous for thousands of years is misleading because radioactivity decay is exponential so most of the activity disappear the first 100 years after removal. Then how long until you reach safe levels depends on what levels you define as safe. Could be infinity if you want since the levels will never reach zero, much less if you compare with naturally existing radioactive ores. The waste is still toxic but no worse than other toxic industrial chemicals. And since there is so relatively little of it, it's fairly easy to handle. I don't see the big problem with burying it deep in the bedrock. In the unlikely event that future civilisations dig it up again, ignorant of radiation hazards, it will be much less dangerous to them. Of course if governments invested in modern reactors we might be able to reuse most of the "waste" as well, reducing the problem further.

author: mikron
author_rank: Contributor
timestamp: July 13, 2015, 08:33:53 pm
content: Quote from: mtdoc on July 13, 2015, 07:28:08 pmAlso let's not forget that there are at least 5 nuclear submarines rotting on the ground of the oceans and dozens more deteriorating in russian navy bases. At least 14 reactors filled with spent fuel were dumped at sea by the soviets.In the USA there's the Hanford site - nine decommissioned reactors and the remains of five large plutonium processing plants.According to wikipedia 200,000 m3of high level radioactive waste are buried here in leaky underground tanks. 4,000 m3of this liquid waste have already contaminated the ground water and are expected to reach the Columbia river in 12-50 years.The stuff that nightmares are made of.

author: mikron
author_rank: Contributor
timestamp: July 13, 2015, 08:37:58 pm
content: Quote from: apis on July 13, 2015, 08:27:50 pm

author: apis
author_rank: Super Contributor
timestamp: July 13, 2015, 08:45:54 pm
content: Quote from: mikron on July 13, 2015, 08:33:53 pmYeah, I don't like the military side of things either, that is a disaster waiting to happen. Only advocating safe modern nuclear for civilian electric production in developed democracies. I think developing countries have a special opportunity to invest in solar now, they are often situated better geographically for that as well. But they too will need fossil/nuclear when solar isn't available. They are going to choose fossil though since it's cheaper and easier... So it's only developed countries that really have the option to expand nuclear instead of coal and gas.

author: apis
author_rank: Super Contributor
timestamp: July 13, 2015, 08:50:25 pm
content: Quote from: mikron on July 13, 2015, 08:37:58 pmThe bedrock is already full of toxic, radioactive and other nasty stuff. It only comes in contact with the biosphere when we go mining for it.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: July 13, 2015, 08:53:32 pm
content: Quote from: mikron on July 13, 2015, 08:37:58 pmTo be fair, I'd be happier drinking tritium water (of a certain concentration) than anything with dioxins in it (of, I think, ppm+ concentration).Come to think of it, that might be a pretty good comparison, actually. Tritium has a pretty short half life, so it's pretty hot. So the concentration will be small for a given amount of activity. I'm not sure offhand if that would also be in the ppm level. (My limit of "a certain concentration" would be something like, X times natural background levels, for a duration of the exchange half life of water in the body.)As for nuclides, the hottest ones are the fastest decaying ones, yes. Like Cs137 and Sr90. They're also some of the most common, and easiest to separate, if you wish to go to that trouble (Cs stays in solution, Sr drops with SO4(2-), fissionable actinides extracted with complexes and solvents; oversimplifying of course, because there's half the periodic table in there, in varying amounts). Once you separate those off, the long lived ones (100-500kyr) are a big hazard: hot enough you don't want them around anybody, too long to do anything with (you aren't going to wait it out; some can be transmuted by further neutron absorption, but not all, and that's an expensive process because it impedes reactor function). Some reactor designs treat actinides this way as well, in which case you get neptunium, plutonium, americium, curium, etc. hanging around too (some of which can be further separated and weaponized).The best current method for everything is probably: separate the short-lived isotopes and let them cook away (or vitrify them too, if possible); vitrify the medium and long lived, useless isotopes; and burn the actinides in a MOX system.Tim

author: T3sl4co1l
author_rank: Super Contributor
timestamp: July 13, 2015, 08:59:39 pm
content: Quote from: apis on July 13, 2015, 08:50:25 pmThe binding capacity of natural structures is interesting; the natural reactor at Oklo had formed in porous sandstone -- necessarily, because the water moderated the reaction. After some millions of years of on and off reaction, followed by a billion of rest, most all of the decay products were found in the vicinity, even the more water soluble ones.For sure, dumping a pile of waste right in an aquifer wouldn't be smart, but old mines could easily be used for this purpose, which descend well below the water table (they still fill with water, because they cut through the table; that porous region would want to be capped).There was also talk of storing material in salt domes, which are presumably not going to dissolve in water for quite a long time.I haven't heard anything (progress or alternatives) about fuel disposal in *years*, so...Tim

author: mtdoc
author_rank: Super Contributor
timestamp: July 13, 2015, 09:11:52 pm
content: Quote from: T3sl4co1l on July 13, 2015, 08:53:32 pmYes. The problem is what happens when large amounts of these are released when there is a reactor accident or when spent fuel rods are not kept cool - as happened at Fukushima.What happens if/when multiple reactor/storage sites cannot be adequately maintained across the globe?Both of those isotopes have significant human toxicity and once accumulated in the body, last decades.

author: apis
author_rank: Super Contributor
timestamp: July 13, 2015, 09:21:44 pm
content: Quote from: T3sl4co1l on July 13, 2015, 08:59:39 pmThere is a slow and seemingly endless debate here. There are long time plans for storage very deep in stable granite bedrock. The spent fuel will be placed in copper containers that will be sealed by friction welding and then put in bentonite clay and the whole mine eventually backfilled. But it's constantly delayed by new concerns which have to be researched. I suppose that's fine though since there's no hurry and it might be possible to process further in the future. But the problems with storage is very exaggerated imo.

author: apis
author_rank: Super Contributor
timestamp: July 13, 2015, 09:41:38 pm
content: Quote from: mtdoc on July 13, 2015, 09:11:52 pmyes but that only happens when there is catastrophic failure which is extremely rare and the damage caused by that (long term) is still smaller than the alternatives. I assume that reactors will be shut down and decommissioned when no longer possible to maintain safely. In any sort of scenario where that suddenly isn't possible wouldn't that be the least of anyone's cancern? Civilization might not last but I don't think it will just collapse over night? Nuclear isn't ideal but looks like the lesser evil to me.

author: mikron
author_rank: Contributor
timestamp: July 13, 2015, 09:59:14 pm
content: Quote from: T3sl4co1l on July 13, 2015, 08:53:32 pmThe problem with tritium is that it is a hard to detect "soft" beta source. It has always been considered harmless because of the low energy of its radiation. Nobody really cared about tritium escaping into the environment.Recent studies show that health risks from tritium may have been under-estimated by a factor of 1000-5000. Since tritium has the same chemical properties as hydrogen it easily accumulates in biological systems. It can replace hydrogen in biomolecules and can easily be incorporated in the DNA. This organically bound tritium is passed through the food chain, but little is known about its metabolization or accumulation.Since incorporated tritium becomes part of the living cell its radiobiological effectiveness is much higher than one would expect. I prefer not to have it in my DNA.

author: mtdoc
author_rank: Super Contributor
timestamp: July 14, 2015, 01:16:04 am
content: Quote from: apis on July 13, 2015, 09:21:44 pmThe fact that such plans even exist demonstrates the danger that spent fuel poses. The fact that they have yet to be implemented demonstrates the human tendency towards short term thinking and the impotence of the political process. SeeYucca Mountainin the USA for a prime example. Why build a long term deep storage facility when you can just cram a few more spent fuel rods into onsite storage pools. What could go wrong?The solution seems to always push the problem into the future - let some future generation of politicians solve it. There's no hurry, right ?

author: mtdoc
author_rank: Super Contributor
timestamp: July 14, 2015, 01:35:00 am
content: Quote from: apis on July 13, 2015, 09:41:38 pm"Rare" is a relative term. Large volcanic eruptions and "100 year floods" are rare events in a single human lifetime yet they have shaped the landscape and the topography of human settlement.The history of the rise and fall of civilizations shows that their collapse is much faster and much more disorderly than their rise. The more complex they are, the more fragile they become and the more rapid and disorderly they collapse. This is the nature of complex systems. (See Tainter'sCollapse of Complex Societiesfor example).I sincerely hope you are right and that all reactors can be shut down and decommissioned safely and most importantly, spent fuel rods can be transported to and stored in appropriate (and yet to be built...) deep underground storage facilities that do not depend on a reliable electrical grid. But as you say, in such scenarios cancer and even radiation sickness, may not be on the minds of those whose job and expertise is such to do these things. Human history shows that the immediacy of war, famine and the need to migrate to safer locales to ensure ones personal and family safetyin the short termtake precedent. The human brain and behaviour/thinking simply did not evolve to deal with these kind of long term emergencies.

author: apis
author_rank: Super Contributor
timestamp: July 14, 2015, 01:47:19 am
content: Quote from: mtdoc on July 14, 2015, 01:16:04 amYes, I believe yucca mountain was based on the same principle.The problem here is more that those who are anti-nuclear come up with one obscure counter argument to the current proposal after another, since as long as there is no long term storage solution they have another thing to criticise.But they might have run out of ideas, I think the nuclear storage ppl are trying to decide on the best location at the moment.Anyway, I meant they might as well entertain the critics, after all if there is something that was overlooked it's important to discover it as soon as possible and with properly maintained short term storage there really is no hurry.

author: apis
author_rank: Super Contributor
timestamp: July 14, 2015, 02:18:54 am
content: Quote from: mtdoc on July 14, 2015, 01:35:00 amyes, and in this case I mean rare enough that the negative effects of the accidents that do happen are less than those of the alternative (coal/gas). And of course, you do your best to minimise risk when planning.Quote from: mtdoc on July 14, 2015, 01:35:00 amIt's hard to speculate about such things which heavily depend on human psychology. But as long as they remember to press the emergency shutdown button and don't activate the self destruct it should be okay.If there is another large scale war it will likely be a nuclear one and in that case we are all screwed anyway. A nuclear meltdown or two is a piss in the Mississippi if they are setting off nukes in the atmosphere all over the globe. Same with mega volcanoes or massive asteroid impacts, etc.So, is it rational to slowly poison ourselves, the planet and the climate with coal power because we fear that nuclear accidents might possibly be worse when/if society collapse?

author: mtdoc
author_rank: Super Contributor
timestamp: July 14, 2015, 07:02:05 pm
content: FYI for anyone interested - there's and EdX course starting on radiation and radioactivity that looks interesting:Effects of Radiation: An Introduction to Radiation and Radioactivity