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Liquid Metal Capsules Used To Make Self-Healing Electronics
MrSeb writes "A crack team of engineers at the University of Illinois has developed an electronic circuit that autonomously self-heals when its metal wires are broken. This self-healing system restores conductivity within 'mere microseconds,' which is apparently fast enough that operation can continue without interruption. The self-healing mechanism is delightfully simple: The engineers place a bunch of 10-micron (0.01mm) microcapsules along the length of a circuit. The microcapsules are full of liquid metal, a gallium-indium alloy, and if the circuit underneath cracks, so do the microcapsules (90% of the time, anyway — the tech isn't perfect yet!). The liquid metal oozes into the circuit board, restoring up to 99% conductivity, and everything continues as normal. This even works with multi-layer printed circuit boards (PCBs), such the motherboard in your computer, too. There's no word on whether this same technology could one day be used by Terminators to self-heal shotgun blasts to the face, but it certainly sounds quite similar. The immediate use-cases are in extreme environments (aerospace), and batteries (which can't be taken apart to fix), but long term we might one day buy motherboards with these self-healing microcapsules built in."
I don't know if I'd want to be on a crack team. I'm more of a coke team kind of guy.
Having to work for a living is the root of all evil.
A crack engineering unit was sent to prison by a military court for a crime they didn't commit. These men promptly escaped from a maximum security stockade to the Los Angeles underground. Today, still wanted by the government, they survive as soldiers of fortune. If your circuits have a problem, if no one else can help, and if you can find them, maybe you can hire... The A-Team.
Does not sound cheap.
Great, so we just need metric tons of gallium and indium, facilities to make it into a special alloy, then redesign all the circuit boards out there to be self-healing. Brilliant!
I want to delete my account but Slashdot doesn't allow it.
Dearest Jake,
Are you even trying any more? I know there haven't been a lot of stories that are easy to troll, but this one is kind of stretching it.
Sincerely,
The Department of Evolutionary Biology
Bio questions? Ask me to start a Q&A journal. Computer analogies available for most topics!
I know it would be an alloy... but Gallium isn't such a great thing to be shipping around in airplanes, etc..watch this youtube video of gallium eating an aluminum can for an idea why.
The liquid metal oozes
Sounds a lot like gravity is the main mechanism for deploying the liquid, in which case any circuit that is not facing "Up" cannot utilize this technology otherwise the liquid will just pour whichever direction is down, which is not always toward the circuit... Or am I just understanding this concept incorrectly?
Ah yes, yet another ingenious solution to the wrong problem.
The main problem these days with PC boards is the exact opposite-- tin whiskers growing BETWEEN the traces, not with traces breaking down.
I once worked for a company that tried to get something like this to work. Wetting was a major problem. PCB traces are prone to oxidation anyway, and if they are in buried layers then they are prone to surface contamination from the epoxy. Although in theory cracks should be clean surfaces, the GaIn has to get there in the first place, and in doing so its own surface may be contaminated. Even a very thin layer of oxide or an organic monolayer may well be enough to prevent wetting. I suspect that this will succeed up to the point they try to make it work successfully in real circuit boards.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
And the formulary used will cause our capacitors to expand and leak self-healing fluid all over the motherboard.
What happens when it breaks a second time? Then it's just as broken.
This kind of thing may help resist a sudden, one-time shock, but it won't do a thing to protect electronics from ongoing wear. Perhaps if there were a way of notifying the device that it had been broken so that it could quickly inform the user and void its own warranty then it would be more useful.
You can't, liquid metal is silent.
How do they prevent this from creating short circuits under stress?
Subject says it all. nuff said.
No, because an EMP destroys most of the active semiconductor devices (integrated circuits and discrete componensts such as diodes, transistors, thyristors, etc), and also many of the passive devices (resistors, capacitors, inductors) in a circuit. It doesn't just create open circuits in metallic PC board traces.
While this has a certain cool factor it is pretty impractical. The chances of a copper trace failing due to shock or vibration are much smaller then the chances of the components that are soldered down failing. Copper is quite malleable. By the time you have deformed a PCB enough to destroy a trace you have probably cracked every surface mount part on the board.
I wonder if this would provide protection against an EMP attack.
That is an intriguing and useful prospect. I would also be curious to know this.
If the only way you can accept an assertion is by faith, then you are conceding that it can't be taken on its own merits
EMPs are a greatly overstated risk, and science does not back Hollywood. There's a video of an actual upper atmospheric detonation of a nuclear weapon, that shows some LLNL physicists on a beach eating hot dogs and steaks. The nuke detonates and temporarily interrupts the transistor radio that's playing, and then it starts working again a few seconds later. No vacuum tubes required.
The only "EMP weapons" that have done anything require direct conductivity (think Tazer). It's a non-issue.
I guess we'll be stuck with "PC Load Letter" forever now
I get what you're saying, but what are the odds of a 1960s transistor radio that Gilligan and the Professor could fix with a soldering iron being a little tougher than whatever 65 nanometer or smaller process they used to make the electronics in your smartphone, desktop, laptop or tablet?
I've also read the bigger problem is above ground wires taking up the energy and frying the gear in the homes and businesses those wires attach to.
The article states this technology is intended to automatically repair integrated circuits via "microcapsules, as small as 10 microns in diameter". Being charitable and going with 90 nm geometries (which we still used in our company last year - we are a bit slow) that's too large by a factor of 100. Interesting for PCBs, but not for integrated circuits.
The article also states that the technology would fix things "so fast that the user never knew there was a problem" and then explains that "a failure interrupts current for mere microseconds".
The summary corrupts that somewhat into the claim that "operation can continue without interruption". It's far too slow for that. Let's assume a rather slow 33 MHz bus - that gives us a clock period of 30 ns - so we'd miss at least 33 clock cycles in this scenario. This interruption might not be noticed by the user, if an error correcting protocol is used on the bus and the system retransmits. Otherwise you would get wrong data, and you have to assume that will be noticed sooner or later.
Interesting technology on PCBs or communication wires, I could see it being used in safety-critical applications. On integrated circuits it doesn't seem feasible. Basically you make the transistors and wires on ICs already as small as you can. To repair the wires on the IC you now need to insert capsules into the wires to do the automatic repair - so they would be way smaller than the wires. If you could manufacture these structures you'd make the wires smaller though and then you'd lose your ability to insert the microcapsules ... there is no way to win that race.
Finally has the technology to build the terminator from Terminator III (the "evil" one) .
Given the built-in anti-static I/O lines on most chips these days, it's definitely a non-issue. You can walk across a room with wool slippers and an amber staff, and you might do some damage, but a nuke far enough away not to cause blast damage isn't going to be a problem.
really? I thought he was going for a +5 funny myself. please tell me he wasn't trying to be serious.
I think the bigger problem here is that you think Gilligan could help the Professor fix something. Kind of lost the credibility of your post there......
Anything that adds cost to PCBs is bit of a no-no - I can't see how the "self-healing" benefit can factor into any PCB design (especially motherboards, which have the least layers possible to reduce cost) unless it is for some specialist application, where using such tech would warrant the extra cost involved.
Cool, but, lets face it - not going to be every day.
biopowered.co.uk - catalytically cracking triglycerides for home automotive use since 2008. Just say no to big oil!
The SI unit that equals 1000kg is a tonne. But the United States, in a fit of parochialism, has decided to rename it a "metric ton". To quote:
So, my little joke was in fact directed at the parent poster, who commented adversely on USA-centricism but used an Americanism for his unit of mass. Personally, I stick to the original SI.
Perhaps you should rename them "freedom tons".
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
Well, yes, but it's still a mind-numbingly lazy troll. We can't just fork out funny points for just anything!
Bio questions? Ask me to start a Q&A journal. Computer analogies available for most topics!
DoctorBob was better. :)
Do what thou wilt shall be the whole of the Law
NO, EMP only destroys semiconductors. Won't bother resistors, coils, capacitors, or vaccuum tubes. If you want an EMP-proof circut, use tubes rather than semiconductors and you're good to go.
Free Martian Whores!
Basically, this is a technology where, if a short develops and a circuit is broken, it will immediately repair the circuit?
Are we sure that is a good thing? If there is a power problem, for example, couldn't that just cause a new short to happen somewhere more expensive to repair?
expandfairuse.org
When you have something like a telecommunications satellite that costs $250 million and has to last 15+ years without maintenance, you aren't looking at the cost of materials for making micro capsules.
You are paying upwards of $100 million / ton for the whole thing anyhow.
I've also read the bigger problem is above ground wires taking up the energy and frying the gear in the homes and businesses those wires attach to.
More likely the fires are cause by short circuts in the power transistors or power supply diodes, causing high voltage to run through wires that just aren't big enough to hanle the voltage.
Semiconductors are extremely sensitive to heat and overvoltage, other components not so much at all.
Free Martian Whores!
In space, no-one can here you scream.
Yes; EMP is an electromagnetic phenomenon whose electrical component is measured in volts per meter, just like the field from a radio or TV transmitter. It is the length of the "antenna" which the EMP intersects that determines the amount of electrical energy induced into the circuit. A long power line will induce a hell of a jolt. A transmitter or receiver with a whip antenna, or anything with any kind of antenna coming out of it, or something electrically connected to something else which it is not immediately adjacent to, is next. A small, self contained piece of electrical apparatus like a pocket radio, cell phone, typical self contained GPS unit, etc, is way down the totem pole for damage.
Starfish Prime, an atmospheric nuclear test in 1962, results: "electromagnetic pulse also made those effects known to the public by causing electrical damage in Hawaii, about 1,445 kilometres (898 mi) away from the detonation point, knocking out about 300 streetlights, setting off numerous burglar alarms and damaging a telephone company microwave link. The EMP-damaged microwave link shut down telephone calls from Kauai to the other Hawaiian islands."
I'm not sure it's a non-issue, particularly given that modern electronics have geometries that are at least two orders of magnitude smaller than anything in 1962, so should be damaged by two orders of magnitude less voltage gradient, and modern weapons designers have apparently made weapons that are optimized for higher EMP, so I would expect that a modern EMP blast would be larger, and electronics more suseptible, than a blast that demonstrably did cause damage to electronics.
Nostalgia's not what it used to be.
It might be useful but in my 30 years of dealing with electronic equipment; I have encountered way, way more faulty components than a burnt or "faulty" run. Of the times I have found a toasted run, there was always a toasted component to go along with it.
My karma is not a Chameleon.
The nuke detonates and temporarily interrupts the transistor radio that's playing, and then it starts working again a few seconds later ... The only "EMP weapons" that have done anything require direct conductivity (think Tazer).
Okay, but how well does a transistor radio work after being microwaved on high for a few seconds? No direct conductivity required...
My computer is so overclocked, I have a pipeline feeding this stuff in to keep repairing the motherboard!
Add liquid metal to a crack - what could possibly go wrong?
If you can't answer that and call yourself an engineer then you don't deserve the title.
Kristopeit still shows up occasionally.
Isn't it better to focus on margins and making sure the worst case scenario is not capable of degrading circuits? If margins are a problem or electron migration is a potential issue be more careful and size your components accordingly.
Even if the capsuls do their job they change the capacitance of the circut upon release right? 10-microns is hundreds of times the feature size of a modern process. So you don't know exactly what percent of the circut is restored you don't really have the capability to model the effect of worst case cap change when the "liquid metal" is arbitrarily released in one or more areas... and you expect the circut to keep functioning as it would normally with no sideffects? Maybe 15 years ago..but really on current and future processes?? Really?
I would rather a system fail outright then become dangerously unreliable. If you need component redundancy do it at the systems level or don't be lazy with your margins.
Improve the lithography and your algorithms if you want more reliability.
The whole "Hollywood hype" attitude dismissing the risk is off the mark too. If anything, nobody prepares against EMP because quite simply there's no reasonable defense against it apart from preventing it from happening in the first place. Protecting the infrastructure is a staggeringly huge and unaffordable proposition which would be a "waste of money" if it never happens, so of course the logical political assumption to make is that it never WILL happen. Ostrich meet sand, sand, Ostrich.
The EMP commission assessment disagrees with your conclusion. It says where EMI protection is baked into the design of product it normally adds little overall cost. Retrofit of existing product is cost prohibitive.
A good example of hollywood being wrong is cars being rendered useless especially new cars with all their "fancy" electronics. Well you know what the EMP commission actually tested "new" cars under the highest field strength their testbed was able to produce and not a single one of the dozens of vechicles tested suffered permanent damage preventing the vechicle from functioning. During the test one or two of them stalled and needed to be restarted. This is because there are already stringent EMI shielding requirements the automotive industry must follow.
Even computers tested were not fried. They rebooted, there were display issues and some of the NICs become unreliable or stopped working due to large induced currents in long ethernet runs. Fiber is not much more expensive than copper and MOVs in circut breakers are effective in stopping induced currents in mains from blowing up your computer. The same way they are effective against induced currents from nearby lightning strikes.
People often point to a past with less transisters and conclude the modern erra is necessarily worse off from an EMP standpoint than it was 50 years ago. The truth is EMI tolerance and effectiveness of protection circuits has progressed steadily for separate operational reasons over the years and it will continue to do so.
Portable electronics is mostly uneffected except for RF gear with antennas attached which has a tendance to get fried.
I don't disagree a large scale EMP is a bad day it would most likely knock out the entire grid which even if completely undamaged would itself take days or weeks to effectivly restart and you can expect lots of physical damage.
However the hollywood notion that EMP = Stone age does not seem to be supported by real world testing.
If they ever perfect this technology, it still won't make it into consumer products.
2 reasons:
First being that it would increase the cost of the product, which cuts into profit.
Second, they want you stuff to break and be unfixable, so you HAVE to buy a new one.
Best use of this idea: Headphones.
Be seeing you...
just a heavier crash, and the main board of the drone has problems. No idea what exactly breaks.
Atari rules... ermm... ruled.
Shirley you jest.
Think of how stupid the average person is, and realize half of them are stupider than that.
ur mum's face still shows up occasionally. cower in my shadow, feeb, etc. etc. etc.
kristopeit is a fucking boring troll, if a troll. so much so to the point that a brain-dead idiot could easily impersonate him. what a loser.
I am not the real Michael Kristopeit.