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Robot Saves the Day at Radiation Lab
An anonymous reader writes "Nature.com is reporting that records released this week by the US defense department read almost like a bad movie plot. Back in October a high-security radiation lab had a cylinder filled with radiation get trapped in its delivery tube network. Fortunately a specially designed bomb-disposal robot was able to retrieve the canister before the radiation was able to eat its way free.
First the "Robot Saves Troops" story and now this. Pretty cool how robots are actually helping us nowadays.
"By now, the robot had been in the radiation zone for 90 minutes. The team decided to regroup, but the robot's electronics had failed and it was rooted to the spot. Thankfully, the team had tied a rope around the machine, and it was hauled in, almost knocking over a radiation shield in the process."
This part sounds remarkably familiar...
"On the third day, and after three weeks of continuous warning sirens..."
Whoah. It took them THREE DAYS? I'm glad this wasn't (obviously) a really serious problem. If it were some sort of radiation based bomb, they'd get fried.
From reading these two articles, it seems that if we could somehow shield these robots from outside radiation, these jobs would be done in a flash.
Unfortunately, we need them to recieve radation because if they DON'T, we can't communicate with them.
Now, I'm not a physicist, but might a Faraday Cage (http://en.wikipedia.org/wiki/Faraday_cage) built with an appropriately sized mesh do the job? Just as a microwave lets some radiation out (we can see the burrito cooking inside) while keeping the harmful radiation in (we don't get toasted by the microwaves), couldn't this be used to do the reverse, that is, allow communication in while shielding the robot from radiation?
I realize that these cages must be in a specific shape to work correctly, but if the core components at least, can be shielded, this go a long way towards solving our problems.
Heck, the arms and stuff we can even make (god forbid) mechanical, perhaps in such a way that they won't get owned by the radiation at all.
http://www.TheGamerNation.com/Forums
But "radiation" can't be stored in a container. Radioactive material, however, can be. Add to that the fact that the submitter was anonymous, and this story should not have been picked up. Hmm. I wonder whats on digg right now.
Drop me a line at:
Key ID: 0x54D1D809
You know, we really get tired of MOST of the dupes here and as we have discussed before, sometimes dupes are a good thing because we don't get all the stories because we're not connected all the time.
This is the first I have seen this story posted here although judging by some of the comments, a quick search would display the duplicate story.
I wonder if there should be a notification icon or something to denote dupes though. Just to appease the dupe hating crowd.
if you steal from one source, that is plagiarism, if you steal from many, well, that's just research.
If they couldn't get the cannister out, would flooding the tube with some form of radiation blocking/absorbing material have worked? Maybe they could have injected it with molten lead, leaded water, or some other radiation dampening material (probably not a permanent solution, but a time-giver).
To make a perfect Faraday cage, you need a perfect conductor. For static electric fields, any conductor will work, but the more it's changing (i.e. the higher frequency the radiation) the better it needs to be. Also, the field is changing when it turns on - it will take time to drop to zero inside if it's a bad conductor.
I'm not sure, but speed of light limits might affect whether even superconductors are good enough conductors for this.
You may not realise, but "salt cellar" (also: "saltcellar") is a perfectly appropriate term for a salt shaker.
quidquid latine dictum sit altum videtur.
It's not the speed of light per se, but the fact that conductors need to conduct *current*, and the current is made up of electrons, which have a finite mass (and, therefore, inertia) a finite charge (and, therefore, a finite amount of current is created when one is moving), and a finite number of them in a given volume.
Metals work as good conductors through the visible because the electrons can move quickly enough in the metal to keep up with the changes in the electric field. With increasing frequency, at some point the electrons will be unable to keep up. This frequency is called the "plasma" frequency; roughly, omega_p^2 = 4 pi n e^2/m, where n is the number of electrons per volume, e is the electron charge, and m is the effective mass of the electron.
Above this frequency, the electrons cease to be effective Faraday shields against electromagnetic radiation. Instead, the acceleration of the electrons causes the electromagnetic radiation to be scattered and dissipate energy through Compton scattering.
Gamma radiation is far above the plasma frequency in all metals. To gamma rays, all material basically looks like a bunch of point charges to scatter off of. So you use something like lead which gets about as much electrons in a small space as possible.
> Now they are working on much higher yeild FUSION bombs.
;)
WORKING? I read about hydrogen (H-)bombs in the late 80s. Here some quick facts: They...
- have 3600 times the power of the hiroshima bomb
- use a nuclear bomb as a fuse (!!!) because nothign else can (or could back then) create so high tempratures that teh reaction can start (some million degrees)
- use heavy (somewhat radioactive) water as explosive, working in a similar way as the sun by making helium out of hydrogen. (which is easyer with heavy water because it already has the needed neutrons i guess...)
- the usa is not the only country that owns them, but it owns (as usual) the most of them.
And: YES, you can kill a small continent with them.
P.S.: Wait for the first rusty ones to explode in russia in the next 10-20 years...
Any sufficiently advanced intelligence is indistinguishable from stupidity.