Interesting post, Jon. I know I'm probably looking at this a bit differently than most of the Design News audience, but machining diamonds to make some sort of machine? That seems like a waste, not to mention, wouldn't the cost factor be an issue given how expensive these gems are?
Not to worry, Beth. The NIST researchers used synthetic diamonds produced at microscopic sizes, so you might still have a shot at a new ring or pendant. NIST won't try to corner the market for mined dimaonds and I doubt it would pay to carve such diamonds into small slices for future MEMS devices. When I worked at DuPont in 1969, a chemist in the nextlab worked on methods to separate synthetic diamonds by size. Because the diamonds were tiny, he tried several techniques to suspend diamonds of different weights at individual levels, or "bands," in a fluid with a variety of flow rates. I don't know how the research turned out.
DuPont's interest in diamonds stemmed from a desire to use explosives in new ways. In this case, to create shock waves that turned graphite into tiny industrial diamonds, not gemstones. DuPont made explosives and I worked in the Explosives Department in the Gibbstown, NJ lab, now long gone. Thankfully the diamond "blasts" occurred at a testing ground away from our labs. --Jon
Great article. It's neat to see something like this that is relatively new. So new, it appears the engineers are really saying, "Cool...so what does it do?" I enjoy hearing about technology that is so recently developed that engineers aren't really sure what to do with it. I think this is where a technology like this can grow into something that is much bigger than the discovering engineers believe.
Thanks for a great article, Jon. I'm certain the good folks at NIST are characterizing their new MEMS materials, but I'm concerned that at least at the macroscopic level, building a complex machine out of diamond wouldn't fair very well. The extreme hardness of diamond would be similar to making gears and shafts out of cast iron -- a very hard material that is too brittle to withstand the stresses involved with machines.
However, I'm intrigued with the creation of square objects with diamond. This reminds me of the very popular "Minecraft" game that permits players to create entire cities complete with complex machinery out of square blocks. When NIST perfects the square diamond MEMS fabrication technique, there will be an army of teenage engineers standing by to create.
From what the NIST people said, it seems more likely they will use diamonds to form the "block" on an engine, for example, rather than the pistons, cams, and gears. Some of the photos on the Sandia Labs Web site show what can happen as silicon "bearings" and "axles" wear. Lots of wear and tear that leads to catastrophic failure. Diamond might make a better substrate rather than a wholesale replacement for silicon in every MEMS device.
For anyone interested in Minecraft, find the Minecraft site at: http://www.minecraft.net/. --Jon
Do any MEMS devices use a lubricant (solid or liquid)? This could be a big deciding factor on how different materials will work together or with themselves. Dissimilar materials might last longer if they run against each other. For instance, at the macro sizes, 2 pieces of stainless or aluminum rubbing together easily causes galling.
As the technique is good at making rectangular things, I suggest the creation of a machine tool in microminiature size. Such a tool needs a programmable motion X-Y Table. One design that might fit the bill is a very miniaturized version of US Patent #4,676,492,1985. The general geometry enables rectilinear motion in X-Y, transfer of vertical loads directly to substrate (there are no piled up stages), and the drives for the miniaturised system can be electrostatic or any other suitable prime movers. Electromagnetic would probably be too bulky.
To keep the product in place upon the X-Y table while being machined or processed, magnetics could be used, or quantum grabbing if the system can be cooled to about -200 C. The same quantum grabbing can also be used as prime mover.
Switched-capacitor filters have a few disadvantages. They exhibit greater sensitivity to noise than their op-amp-based filter siblings, and they have low-amplitude clock-signal artifacts -- clock feedthrough -- on their outputs.
For industrial control applications, or even a simple assembly line, that machine can go almost 24/7 without a break. But what happens when the task is a little more complex? That’s where the “smart” machine would come in. The smart machine is one that has some simple (or complex in some cases) processing capability to be able to adapt to changing conditions. Such machines are suited for a host of applications, including automotive, aerospace, defense, medical, computers and electronics, telecommunications, consumer goods, and so on. This discussion will examine what’s possible with smart machines, and what tradeoffs need to be made to implement such a solution.