Power Sources for Smart Dust?

An interesting thought but I imagine that due to the very small area that would be impacted and the otherwise random motion that designing a means of extracting energy would be hard but maybe with nano-technology it could be addressed. Still, it seems doubtful.

Thanks for the feedback rcapper much appreciated. PM10s are the bane of congested roads. particulates smaller than 10 microns, They remain almost constantly airborne till rain washes them down. Ten microns is now 'gigantic' in the nano-fabrication industry. I have seen almost perfect square wells one micron diameter, 2.5 micron centres, 40 micron deep in a Beta-Voltaic honeycomb application. Ten microns would be too small, 20 microns would be better. Think of two boxes made of silicon, each with a nano spring, a bit like a bed spring at the bottom of each box? A ten micron Neodymium magnet is suspended in the middle when the two boxes close. naturally a conducting coil surrounds the box. That little magnet might bounce back-n-forth like crazy? ...If thin film capacitors were included at the flat ends of the box, when fully charged, there might be sufficient power available to fire up a few semiconductors ?

Other configuratins of magnet and coil might work better, The concept could warrant further investigation. Justification is clear, but let's not go there.

If these were manufactured from thin film silicon sheet, much like blocks on a chocolate bar, billions of dust motes could be manufactured at negligible unit cost.

OK its a Pipe Dream, but the physics is sound I believe.

The 'torch' caught me a bit off-guard but the little program was interesting. Now are you trying to make a piece of magnetic dust generate electricity through its motion, or are you trying to get electricity into the dust?

Either way, if the program is right, the particle gets more motion with a lower density of gas. That was intruguing.

Also the issue you're going to have is heat. Without trying the expriment, I bet a magnet ground into powder and shaken inside a coil would generate a lot of heat when the electricity from the coil was used. Small things can't handle heat very well as they have too small a surface area.

The only reason that the shaken torch works is that it converts some of the energy used to shake the torch into electrical energy. With the Brownian motion the only reason that the entire system keeps working is that the collisions are 100% efficient. If you tried to use the collisions then the particle being impacted upon would ultimately drain the energy from everything around it. But this would violate the first law of thermodynamics so overall I don't think it would work

Something else though is that if you watch closely you will see that occasionally two of the smaller particles end up in a sort of embrace and shoot of orbiting each other. My question is dose this really happen and if so why or is it a glitch in the program?

That would be sort of neat. Having fine enough magnetic particles to be moved around by the gas, extracting the energy with coils surrounding the bunch of stuff, and the gas losing energy. Would we have cooling? Would the gas liquify over time?

I wish I had the necessities of producing a magnetized dust light enough to mix with whatever gas(es) could be sealed in the chamber.

Sadly, though, I think Masu is correct and the dust would simply settle out, if not to the bottom, then to the sides of the container.

Thanks, 'jdst' What I have read so far about 'Smart Dust' is that it is hardly 'dust' at all, more like smart 'sand' and the sticking point is the power supply. I have just read how Carbon Dioxide is the main feedstock for 'Nanotubes' and that with a concerted effort all our surplus CO2 from power plants could be converted to this amazing fibre. I would add that chemical vapour deposited diamond can also use CO2.

Chemical Engineering and Nanotechnology seem to be best buddies at the moment. let's go on a flight of fancy and 'chemically' engineer a 'piezo' mote of dust, Goodness knows how?....and make it 'bristle' with carbon nanotubes? a bit like a sea urchin....There it is 'wafting' about on a light breeze, but importantly, constantly bombarded with molecules of air.....one little air molecule bashes into this micro-airborne rolled up hedge-hog;.. well as I see it, the molecule is going to bend at least three little nano-tubes, as it forces it's way to the centre of the spherical prickly dust-mote?..... If this was made from say a piezo/pyro plastic resin like PVDF....then 'possibly'??? an EMF might be generated. Flocking techniques, i.e. electrostatic charge conceivably at least, might attach the nanotubes while the resin was still sticky?...... If that PVDF resin was diluted and coated a suitably engineered micro-circuit?...OK I know my limitations and I may be talking balderdash from a specialists point of view, but my point is "give it some thought" there is nothing to lose. and potentially a whole lot to gain. Even save a life or many lives.

Thanks For the input Masu, Point taken, we are somewhat out of the box here, but that is half the fun. Here is an interesting link:-

http://physicsweb.org/articles/news/6/7/11

Quote:-

Small systems defy second law

16 July 2002

"A deviation from the second law of thermodynamics has been demonstrated experimentally for the first time. Denis Evans of the Australian National University and colleagues have shown that entropy can be consumed – rather than generated – in small systems over short periods of time. The achievement fulfils a prediction made by Evans and colleagues ten years ago (G Wang et al 2002 Phys. Rev. Lett. 89 050601).

The second law of thermodynamics says that the entropy – or disorder – of an isolated system undergoing a cyclic process will increase or remain the same. But this law only applies to large systems over significant periods of time. To explain the behaviour of smaller systems, Evans and colleagues devised their 'fluctuation theorem', which calculates the probability that entropy will be consumed at any point in the cycle. They found that it predicted that measurable violations of the second law would take place in small systems over short time-scales.........etc."

Perhaps at this stage it would be helpful to avoid specific examples from the 'macro' world, with a strong possibility that miniaturised to the 'micro' world, all sorts of problems like Van de Waals forces etc. might invalidate the proposition. Essentially asking if electricity could be generated at the nano or micro dimension from Brownian Motion. Poetically stated>>> "How good are Maxwell's Demons at Baseball or Cricket? Can they catch?"<<< and if we could do the intricate cabinet work required, could we harness the kinetic energy of the 'ball' to power an electronic circuit? A possible justification might be a bunch of chemical/gas sensors that were allowed to drift about a petroleum refinery. If a mote or two of 'smart dust' detected a leak, it's fully charged capacitor could fire off a QRP signal, received at multiple base stations, back bearings would give a precise location of the potential leak. Multiple alarms from dozens of smart dust motes could trigger emergency action stations?

Postscript:-

For anybody wanting to have a little fun, why not play 'Maxwell's Demon' and try to beat the First 'Axiomatic' (i.e. No Proof Required) Law of Thermodynamics, then Check out:- http://ajs.net/maxwell.htm

Brownian Motion enthralled Albert Einstein, Now we have reached the dawn of molecular engineering, are we safe to assume a gigantic 'LAW' (i.e. The 1st of Thermodynamics) can be grounded upon the quicksand of superstition and prejudice, rather than the bedrock of Logical Proof.

But a profound reversal of reasoning has occurred in the last century. Helmholtz originally said "Because a Perpetual Motion Machine is impossible, therefore the First Law of Thermodynamics;" while in any physics text book today one will find the statement that "Because of the First Law of Thermodynamics, a Perpetual Motion Machine is impossible."

Check out:- http://www.aip.org/history/einstein/essay-brownian.htm

Has your 'Avatar' morphed 'masu'? (Shades of the Cheshire Cat's Smile from Alice Springs in WonderOzland)......Mmmmm. Very nice analogy there 'masu' 100% efficient collisions, surely this is the standard 'kinetic' model for gases. In a thought experiment we could scale up and allow the gas molecules to become like those super-bouncy balls we used to play with as kids, only 100% efficient.

Assume all these balls are bouncing round chaotically in an evacuated chamber(i.e. no air friction either) If we introduced a football into this crazy scenario, we might visualise it as being knocked about all over the place.....CHAOS..... it's a powerful source of energy, because it is never 'balanced' the 'force vectors' due to repetitive impacts from the super-bouncy balls will hardly ever allow the football to remain stationary in mid air, it will jump about to & fro.....'Brownian Motion'.....Playing the 'Maxwell Demon' game (link below) I noticed a rather interesting phenomenon, possibly an artifact of the Java-Script software, but if not a software artifact, very significant.

The slow blue molecules tended to just bounce about randomly, but the faster red molecules started to form into a symmetric wave, oscillating about the Maxwell Center Line. It made it very difficult to unbalance the temperatures beyond a few degrees, but pressure was much easier to unbalance. The Google video link depicts the weird and wonderful world of crackpot inventors, who keep their inventions ultra-secret and use what look like very dodgy measuring equipment.

The problem with Brownian motion is that it only holds true while the particles are extremely small ant they are of similar mass and size. If you increase either the mass or size of the red dot then the motion either ceases or fails to become random. That sort of kills off any macro level event. Something else I thought of was that Brownian motion only happens because on the microscopic level matter and energy are not evenly distributed. If you introduce magnetic fields that encompass large numbers of molecules then the whole thing collapses and the motion ceases.

Did you notice the phenomena I mentioned earlier of the two grey particles grabbing hold of each other and spiraling off in a sort of deadly embrace? What do you think is going on here? Is this a software glitch or dose it really happen?

PS I changed my avatar because somebody else started using the other one so I decided a change in colour was necessary.

Thanks Masu for those observations. Pollen sizes vary between 30 to 90 microns in diameter. Brownian motion is observed clearly at these dimensions. They get quite a pounding as seen under a microscope.

Quote:-

Abstract from The University of Rochester NY;

This paper presents a unique type of transistor that is intended to operate to THz frequencies and beyond, at room temperature, with low noise and with very low power requirements. This transistor is unique in that no doping junction or barrier structure is employed. Rather, the transistor utilizes a two-dimensional electron gas (2DEG) to achieve ballistic electron transport in a gated microstructure, combined with asymmetric geometrical deflection. We call it the "Ballistic Deflection Transistor"(BDT).

In 2001 IBM announced a logic gate the size of a single carbon atom.

So what do we have to advise the Nano-Smart-Dust-Geeks? They will be keeping abreast of advances. What will the Sony Corporation be doing with Smart Dust to enhance their Virtual Reality Play-station? that has cost so many billions to develop so far.

In Geek-Land, anything is possible. Smart Video-Dust, at Giga-pixel resolution in awesome full surround 3D. with surround sound audio. But let of the smart-video dust bomb in the woods first. Then invite your Japanese Friends to play the latest game.

After a few hours the definition starts to fade as the virtual reality ultra-high definition picture loses clarity.......Time to head home for tea. The Forrest is saved to Play-Station memory, right down to definition as accurate as a stamen on a blossom, or a spot on a beetle's wings. After Tea, The Kids can do their Homework searching for Flora and Fauna.....and perhapslater that evening, invite their new found friends back to the enchanted forrest again......

Sign me up....I want to be an "OLD GEEK!" and play with the grandchildren now growing up so fast. 6 years old already....how time flies.