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DIY Synthetic Aperture Radar
An anonymous reader lets us know about a DIY synthetic aperture radar built for $240 in parts (give or take). Here's PDF slideware from the Ph.D. student's research. "Using a discarded garage door opener, an old cordless drill, and a collection of surplus microwave parts, a high resolution X-band linear rail synthetic aperture radar (SAR) imaging system was developed for approximately $240 material cost. Entry into the field of radar cross section measurements or SAR algorithm development is often difficult due to the cost of high-end precision pulsed IF or other precision radar test instruments."
I'm part of a team who did something similar (We're presenting it at IEEE MWSCAS, it's much less cool than this, though). We built several thousands of dollars worth of test equipment using cheap junk and came out with stuff that was just as good. DIY folks have been doing this for decades, of course, but PhD students are now starting to publish these things. This is a big deal, and means that legitimate researchers can pick up this work and very easily enter a field of research their institutions may have previously been unable to fund. Our school has always just enlisted students to design and build all of our test equipment, but still. This is good.
I didn't RTFA, but I certainly hope they've open-sourced their backend interface software and hardware designs as well. Of course, if you're disassembling a microwave, you can hardly patent the technology. Closing off access to your work kind of defeats the purpose in science, though.
When you're afraid to download music illegally in your own home, then the terrorists have won!
This could fall into the hands of terrorists.
Citizens are consumers. We are passing Intellectual Property laws, to ensure that they remain so, and do not make the mistake of becoming producers.
This man's brilliance sets another difficult example and precedent, which will be hard to contain or dismiss! I suggest a patent law-suit against him, and a criminal charges based on illegal production of weaponizable technology.
"Speaking the Truth in times of universal deceit is a revolutionary act." -- George Orwell
Can you mount this on your car? Maybe torch the guy who cut you off in traffic?
I want to delete my account but Slashdot doesn't allow it.
A strange thing happened shortly after this equipment was assembled and tested. I noticed that whenever I got angry, my skin would turn green and I would tear off my clothes.
This seems to be from 2006/7...
"A National Instruments PCI-6014 data acquisition card triggers radar pulses and digitizes the video data". http://sine.ni.com/nips/cds/view/p/lang/en/nid/11442 With a $700 (not counting accessories) data acquisition card.
My god, it's like it's 2004 again!
No, the AC is just a Mac user who finally got to play Portal when he downloaded Steam.
This ain't rocket surgery.
That total cost of 240$ is based on them acquiring used material at a radio swap meet, not scavenging it from old stuff I could find in my attic, and definitely no buying from some online supplier. That is, w/o a lot of luck, time, and knowledge- there is no way I could duplicate this effort with ease.
I worked for a company started by a person who did SAR research in school. His project was based off an earlier one done by my current business partner at the time. A small rail track is still mounted on top of the engineering building at the university from these projects.
The big difference with what that company, www.ImSAR.com, is doing and anyone else is the size. The system they developed is 2lbs and smaller than a shoebox. At the time, the next smallest system was 50 lbs. This little box can fly a a payload on an 18 pound UAV. Check out the website for some pretty cool images of the unit and generated SAR images. IEEE Spectrum magazine did a cool piece on it in the Jan 2009 issue.
The system was running an ARM with montavista and did realtime (within a few seconds) calculations to transmit the video down to the observer. The antenna is a printed PCB and is mounted on a gimbal that moves using RC airplane control servos. To test the thing quickly, we'd hop in a car and mount it to a bracket on the window and go cruise around town. Definitely got some strange looks doing that. The boss even was once stopped by the cops because of "suspicious activity" that had been reported. Since then, they've now build a small RC plane that can fly it around for quick testing instead of a car.
Looks like your technique is flawed.
When you're afraid to download music illegally in your own home, then the terrorists have won!
I would think most of the great Ph.D.'s would be DIY, else what's the point? Your thesis is supposed to be original research, and serious research at that, so I don't see how coming up with a way of building extremely expensive technology at a tiny fraction of the cost in your garage is anything but exactly what a Ph.D. thesis is all about.
It's not a book report or high school research paper, you know.
Security is mostly a superstition... Avoiding danger is no safer in the long run than outright exposure. - Helen Keller
I'm impressed with what this guy found at a hamfest. We don't see much microwave gear in Silicon Valley surplus any more. eBay, though, has a decent selection of microwave horns, low noise amplifiers, mixers, and waveguide. It looks like anybody could get the necessary parts in small quantity. New, though, those parts are expensive, so building low-cost robot vision systems this way is hard.
Also, when your "garage machine shop" has a Bridgeport milling machine, you're way above the usual home shop level. Still, if there's a TechShop in your town, you can get access to such machines.
A big problem working in this area, even if you know what you're doing, is that the test gear you need costs more than the thing you're making. Reading the design notes, some of which are on Air Force Research Lab stationery, indicate that the hamfest parts were tested and characterized using reasonably good test gear. And this was an MIT student, with access to MIT labs.
I ran into that building a small LIDAR in the early 1990s. The parts cost wasn't too bad, but I needed access to about $20K in test gear to debug the thing.
That's a reasonable response. I think you would find many PH.D.'s - at least in the sciences, I won't venture to comment on the arts or fine arts - are entirely theoretical which I hope you would agree are not DIY - at least not DIY in the colloquial sense as I understand it. On your assertion that there is no point if it isn't DIY let me say that if it had been a thesis E=MC**2 would not be DIY, but I hope you agree there would be a point to it.
That would depend entirely on why it is inexpensive compared to the traditional alternative - which is one reason why I made my comment relate to the accuracy of the article summary. I agree the Ph.D. is supposed to be serious and original research. It is also supposed to contribute to our intellectual understanding of things in a significant way. Suppose there was a problem domain in which the best solution was so slow that the problem was, for all practical purposes, not solvable. Now someone comes up with a solution that makes getting an answer so fast that it becomes practical for many applications. That might be worth a Ph.D. and in part that would depend on how that new solution contributed to our deeper understanding of the original problem or some other problem of intellectual significance.
Is coming up with a better approximation algorithm for travelling salesman of the same intellectual calibre as developing a proof for PNP?
I would say no, and that the former would be a good Master's while the latter would obviously be a Ph.D. However the former could be a good Ph.D. if it also shed some light on the P, NP question or if it approximated the solution in a way fundamentally different than other approximations to the problem.
One thing I might look at in the research that this article concerns is whether it was of the "we found a completely different way to do this and demonstrated it using cheap components, and this new method can be developed into a commercial product equalling current commercial products but at a fraction of the cost" type or was it "we built something essentially the same as existing systems, or different only in minor ways, but we used cheap components to achieve the same end" (or even "and resources that are actually quite valuable but happened to be cheap/free to us because of our unique circumstances"). And does it advance our understanding of synthetic aperture radar in a fundamental and significant way? But IMHO only making something financially cheaper isn't in and of itself worth a Ph.D. Of course YMMV.
As the the Anonymous Cowards foaming at the mouth about "dissing" someone's work or demanding proof that I have done better or... clearly they have no understanding of the intellectual discourse expected in the Academy or of what entitles someone to critique something or to hold a dissenting opinion. I could be unkind but I'll refrain.
The tyrant will always find a pretext for his tyranny - Aesop
$150 to $450 on EBay, but still your point is valid.
Even if it is $700, his point still doesn't invalidate the researcher's point: technology which the conventional wisdom holds is only available to organizations with large budgets is actually available at what are essentially middle-class consumer prices.
The point isn't that you can do it for precisely $500 or $700 or $1200 or $2000 or $5000. The point is if you know someone with reasonable engineering skills and you can raise a few thousand bucks, you can build this stuff.
If nothing else, this has significant ramifications for asymmetric military conflicts...
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