×

Welcome to the Slashdot Beta site -- learn more here. Use the link in the footer or click here to return to the Classic version of Slashdot.

Thank you!

Before you choose to head back to the Classic look of the site, we'd appreciate it if you share your thoughts on the Beta; your feedback is what drives our ongoing development.

Beta is different and we value you taking the time to try it out. Please take a look at the changes we've made in Beta and  learn more about it. Thanks for reading, and for making the site better!

DIY Synthetic Aperture Radar

kdawson posted more than 3 years ago | from the be-the-first-on-your-block dept.

Hardware Hacking 118

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."

cancel ×
This is a preview of your comment

No Comment Title Entered

Anonymous Coward 1 minute ago

No Comment Entered

118 comments

Aperture Science (0, Offtopic)

Anonymous Coward | more than 3 years ago | (#32612698)

The cake is a lie.

Re:Aperture Science (1)

biryokumaru (822262) | more than 3 years ago | (#32612752)

My god, it's like it's 2004 [xkcd.com] again!

Re:Aperture Science (3, Funny)

gyrogeerloose (849181) | more than 3 years ago | (#32613082)

My god, it's like it's 2004 [xkcd.com] again!

No, the AC is just a Mac user who finally got to play Portal when he downloaded Steam.

Re:Aperture Science (1, Funny)

Anonymous Coward | more than 3 years ago | (#32613094)

It's okay. The sequel is coming out soon.

Portal jokes will once again become relevant in 3... 2... ::static::

Re:Aperture Science (0)

Anonymous Coward | more than 3 years ago | (#32613106)

best xkcd ever!

Re:Aperture Science (0)

Anonymous Coward | more than 3 years ago | (#32613072)

Asdfuc cuumsl sluud pifffg drtun an duazo?

Crooks (4, Insightful)

biryokumaru (822262) | more than 3 years ago | (#32612744)

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.

Re:Crooks (2, Informative)

rrhal (88665) | more than 3 years ago | (#32612872)

TFA is and abstract to a paper and some links. He's generating his synthetic aperture by moving the radar head on a rail (modified garage door opener style). I was curious how he went about getting the necessary motion.

Re:Crooks (2, Insightful)

kalirion (728907) | more than 3 years ago | (#32613000)

Yup, definitely sounds like something crooks would do.

Wait, what am I missing?

Re:Crooks (2, Insightful)

biryokumaru (822262) | more than 3 years ago | (#32613042)

Haha, sorry, I never got to the point on that. The crooks are the people who charge $10,000 for something you can build in your garage for $50.

Re:Crooks (5, Insightful)

jschottm (317343) | more than 3 years ago | (#32614374)

What's your point? The grocery store wants to sell me a red pepper for $2 that I could grow for a few cents. That doesn't make them crooks, it's just the nature of capitalism and value add. Raising your own produce is only cheap if you know how to do it, have the space to do it, and are willing to put in the time to do so. And if your time is free. The free market also provides other options - I can get them cheaper at the farmers' market, but only during certain portions of the year and only if I'm willing to shop at specific times. It's all about tradeoffs and what people are willing to pay for.

The crooks are the people who charge $10,000 for something you can build in your garage for $50.

Most people can't build anything of the kind for any amount of money. How many people do you think know how to solder? The reason why this guy was able to build this for $240 is because he has a $150,000+ education, is far above average, and has access to the tools needed to make this.

Are you proposing that you get paid minimum wage once you graduate because students are willing to work for free or cheap on projects? Or do you expect to get paid enough to live above a student quality lifestyle, pay back student loans, support a family, etc.? Are you advocating for communism?

Does your $50 test equipment have a warranty? Support? Certification? Documentation? Insurance covering damages if it should short out and burn down the lab? Can a replacement be overnighted from the factory if need be? Are you factoring in the fact that your university is subsidized by research grants, donors, and possibly the government (if it's a public school) which distorts true costs? Are your scavenged parts going to be reliable? Are you providing health insurance for the people building the gear? Unemployment insurance? FICA? Paying rent on the facility? Allowing for a middle salesman who'll be vital to getting your product into customers' hands?

The basic fact of capitalism is that you price your product and/or service as high as you think the market will pay. Unless there's a monopoly, either you've priced yourself appropriately or someone will undercut you and you'll have to lower your prices or go out of business. There's nothing wrong with aiming for the high end of a market. If you can double your prices and still get half of your business, you're doing less work for the same money. Of course, your customers might not be very loyal as a result.

If you think that the test equipment is overpriced, once you graduate, find some investors and start your own company with better pricing. But I'd recommend taking a few business classes first. Even if you got your parts, tools, shipping, and rent for free (and paid no taxes), you'd still have to make and sell 4 or 5 pieces of test equipment at $50/each every week just to pay yourself minimum wage.

Re:Crooks (1)

biryokumaru (822262) | more than 3 years ago | (#32614618)

Well, capitalism is nice for paying the rent and all, but it's still contrary to the nature of the pursuit of knowledge. I'm just saying that the spirit of open source is spreading in a meaningful way into more facets of academia than software, and that's a good thing.

Additionally, I'm not starting a business and selling this crap for $50. I'm making it so that anyone who wants this equipment can easily assign some undergrad to toss it together over a weekend. I don't see why it should cost an arm and a leg for equipment when the knowledge behind its implementation is free. We should make the design and construction free, too, so that anyone could do it for cost, instead of supporting an endless stream of middlemen who do not add value. That's just more information, right? It just adds to the compendium of human knowledge, right? Why do I need to profit from it?

Regardless of what you think is the proper use of knowledge, not all of us want to be crooks.

Re:Crooks (1)

ObsessiveMathsFreak (773371) | more than 3 years ago | (#32618090)

You go on and on about capitalism and the free market but the basic fact of the matter is that there are so few people demanding these devices and so few companies selling them that the rules theorised for grain and bullion markets simply do not apply. There is enormous price gouring and manipulation going on by companies who have cornered these so called "markets", which are in reality simply landlord/tenant relationships without the corresponding protections.

These devices cost less to make than a DVD player, yet are being sold for a thousand times the price. No matter how much you twist and bend them, your free market theories will never be able to explain this, and neither will your complaints about government interference. Only the iron laws of monopoly and market manipulation have a hope of explaining these kinds of margins.

Re:Crooks (1)

saider (177166) | more than 3 years ago | (#32615738)

People pay $10k for a $50 widget because of the time needed to certify that the $50 dollar item was built correctly and works as intended. You can try to sell me the $50 item, but if my manufacturing process needs things like a calibration certificate traceable to a NIST standard, then I'm going to buy the $10k item, deliver on time and charge the customer. I don't have time to certify that the device operates as intended (which requires time and a whole other set of equipment). Customers are much more interested in saving time than saving in material cost because (at least the stuff we do) engineering labor costs far exceed material costs. Engineering labor is kept low by making sure that we are not buried in unnecessary tests and documentation.

Re:Crooks (1)

hjf (703092) | more than 3 years ago | (#32616240)

Um, no, people pay $10k because companies ask for that. And companies ask for that not because of the certification crap, but because it's not mass produced. Any microprocessor today has more R&D, testing, certification and all you can name, but it doesn't sell for $10k. On the other hand, test instruments (for example) don't have such a huge market (like a microwave frequency generator, or a 50GHz scope, or even a 300A regulated power suply). So when you divide all the cost (especially human - those scientists dont work for free) by the number of units produced, it's a really high number.

DIY == Ph.D.? (1)

Have Brain Will Rent (1031664) | more than 3 years ago | (#32613426)

DIY is great - but is it worth a Ph.D.? I don't think so. I hope the guy did something more fundamental than the summary might lead you to believe.

Re:DIY == Ph.D.? (0)

Anonymous Coward | more than 3 years ago | (#32613454)

Really? What have you done with your PHD?

Re:DIY == Ph.D.? (1)

Have Brain Will Rent (1031664) | more than 3 years ago | (#32613574)

I could tell you but during my prior advanced degree I developed a technique to avoid feeding trolls. Have a nice life.

Re:DIY == Ph.D.? (0)

Anonymous Coward | more than 3 years ago | (#32613584)

Whatever you say, loser. You ain't got anything on this guy.

Re:DIY == Ph.D.? (3, Funny)

biryokumaru (822262) | more than 3 years ago | (#32613638)

Looks like your technique is flawed.

Re:DIY == Ph.D.? (1)

Have Brain Will Rent (1031664) | more than 3 years ago | (#32614038)

Naahhh, giving them the bird isn't feeding them.

Re:DIY == Ph.D.? (0)

Anonymous Coward | more than 3 years ago | (#32615452)

That's what you think, loser.

You've been called out and came up empty handed. We all know what that means. It means you have nothing to show. You're probably some sad little pizza delivery slave who thinks he's smart but just too smart to do anything productive. Again, we all know what that means. You claim to be smart, you can figure it out.

Re:DIY == Ph.D.? (1)

X0563511 (793323) | more than 3 years ago | (#32617868)

Yes, it is. The only way to starve a troll is to ignore it. Any attention, positive or negative, is food.

You should probably go take a refresher course. It seems you've lost some of the fundamentals.

Re:DIY == Ph.D.? (1, Insightful)

Anonymous Coward | more than 3 years ago | (#32614002)

Seriously, he isn't a troll. You opened your yap to dis some guys work, and you were requested to provide a reason why you feel qualified to so. So put up or shut up and be known as a weasel.

Re:DIY == Ph.D.? (0)

Anonymous Coward | more than 3 years ago | (#32617074)

How about this. In my field and in my school, to get your Ph.D. we were required to publish 2 first author papers in well respected peer-reviewed journals.

This doesn't look like it would make it over that hurdle, but it's not my field, they my have different criteria.

Re:DIY == Ph.D.? (3, Insightful)

Bigjeff5 (1143585) | more than 3 years ago | (#32614314)

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.

Re:DIY == Ph.D.? (1)

biryokumaru (822262) | more than 3 years ago | (#32614658)

Haha, book report... no, people don't get degrees from book reports, they get them for doing a "literature review!"

Re:DIY == Ph.D.? (2, Insightful)

Have Brain Will Rent (1031664) | more than 3 years ago | (#32615430)

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.

building extremely expensive technology at a tiny fraction of the cost in your garage

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.

Re:DIY == Ph.D.? (0)

Anonymous Coward | more than 3 years ago | (#32615582)

This particular Anonymous Coward actually agrees with you but it seems to me that in the field of engineering advancing understanding is not necessary - all you need to get your PhD is to do a project to solve an existing problem using known tools, provided that the particular solution was not published before. Sure, working out all the details takes a lot of dedication and often clever thinking, but advancing our understanding of the subject? Not really.

Re:Crooks (0)

Anonymous Coward | more than 3 years ago | (#32613462)

This guy's work sounds very cool, but I'm surprised he's doing it for a PhD. As my adviser often says, "you don't get a PhD for building something." You need to at least be able to sell people the idea that what you've done advances the theoretical foundations of your discipline. Usually that just means using more Greek symbols in your papers, and calling statements "Theorems," but nevertheless that's what you have to do (cynical enough for ya?). And since this is what's valued, people pretty quickly figure out that their "experiments" (really "demonstrations," but they're rarely called that) should be quick afterthoughts -- preferably which look good and give a cool-looking dog-and-pony-show video. So it's surprising both that design and fabrication (as opposed to theorem-proving) seem to have consumed the bulk of this guy's time, and that he's presenting his work as "Hey look, we hacked it together for cheap out of junk" and not "we developed novel algorithms for foo and bar based on [obfuscatory mathematical formalism that doesn't actually contribute any new ideas but we won't say that]." It doesn't sound like he's destined for academia.

My second thought is that this is "cheap" only because of the glut of grad-student and postdoc labor in the market that can reinvent the wheel out of power tools.

Well, I've been working on an idea for a while (1)

jd (1658) | more than 3 years ago | (#32617644)

That could use stuff like this. I have been working with a group of British archaeologists at the Mellor Archaeological Trust for a few years and they have a superb site - but much of it is either impossible to excavate or too expensive. So they started working with Ground Penetrating Radar. Interesting novelty toy, but it only tells you where it might be interesting to dig, it doesn't really help avoid digging.

At the SC2005 supercomputer show, I saw demonstrated reverse tomography techniques. Ah, this looks better. Being able to take the output an generate a visual representation. Problem is, ground isn't uniform so you've a lot of refraction and reflection to contend with. Possible solution - the game Black Box. If you know where you put the rays in and know where you get the rays out, with sufficient rays you can determine where things must have been to produce those results.

Next problem: Objects aren't of uniform shape and size, and signals aren't transmitted vertically downwards. The result is that the output will be scattered in all kinds of directions, where those directions depend on which direction the radar is facing. Solution - have many receivers, some at fixed points and the regular one on the GPR set.

Next problem - the signals used are bloody weak, but the depths you need to scan to are incredible. It isn't possible to build a single receiver large enough to pick up the extremely faint signals you're going to get at any depth. At great depths, sacrificing the fine detail for any detail at all seems reasonable. That means turning the collection of receivers into one large virtual dish.

And this is where the article comes in. Interferometry is a great technique for a constant signal, but radar is pulsed. You need something analogous for radar systems, which is your synthetic aperture radar.

You do the scan of the ground as a grid once for directional sensitivity and then again for signal sensitivity.

There is, of course, one other problem and it's big. The same set of results can come from multiple possible sources. It should be possible to use herustics to try and find potential solutions, and then conduct further scans which either eliminate or confirm those possibilities.

Isn't this a lot of work? Yes. It's a hell of a lot of work. But the site involved has too many areas of extreme interest where non-intrusive scans MIGHT get permission, but where any kind of digging - so much as a teaspoon - would get you hung, drawn and quartered. And then forced to watch Bob Monkhouse reruns.

To me, this is why the paper is interesting. It tells me if this kind of vision is even possible, it tells me something about what the requirements are, and it tells me whether it would be more cost-effective to actually do it or wait.

Re:Crooks (1)

DerekLyons (302214) | more than 3 years ago | (#32615950)

We built several thousands of dollars worth of test equipment using cheap junk and came out with stuff that was just as good.

And of course, you calibrated it against known standards so you know that for certain. (Calibration is what makes the difference between cheap junk and useful equipment.)
 

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

Yes, it's a big deal. DIY grad students, PhD candidates, etc... have been cobbling together such equipment for decades as part of their research - but now our education system has sunk so low that what generations past considered part of their background work on the way to real research is now thought worthy of a PhD dissertation.

Re:Crooks (2, Insightful)

biryokumaru (822262) | more than 3 years ago | (#32616064)

It represents the distinction between every student having to reinvent the wheel for every project, and future students being able to build more complex testing equipment by combining together others' works.

Saying this is bad can be liken to decrying scientists for standing on the shoulders of giants.

Stop Him Now (5, Funny)

Philip K Dickhead (906971) | more than 3 years ago | (#32612786)

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.

Re:Stop Him Now (1)

Bigjeff5 (1143585) | more than 3 years ago | (#32614338)

It's really sad that you were marked "insightful" instead of "funny".

Is satire dead in this country?

Re:Stop Him Now (1)

Black Gold Alchemist (1747136) | more than 3 years ago | (#32614530)

Because satire can be insightful.

Re:Stop Him Now (0)

Anonymous Coward | more than 3 years ago | (#32615170)

Can be? If it's not insightful at all, I don't think it's Satire. Satire isn't merely a form of humor, it's a methodology that uses humor as a means of communicating a point, usually in regards to an intrinsically flawed system or viewpoint.

I would have never guessed... (0)

Anonymous Coward | more than 3 years ago | (#32612812)

that the a Ford Mustang would be so stealthy! Seriously compare the image of the car on slide 21 to all the other targets they tested this thing on.

Re:I would have never guessed... (0)

Anonymous Coward | more than 3 years ago | (#32613060)

And who would have thought that rearranging the letters to GOSTATE almost spell GOATSE!

Re:I would have never guessed... (1)

budgenator (254554) | more than 3 years ago | (#32613526)

I thought that was pretty interesting as well, doing before and after scans after body and paint mods might be very popular in areas where the police use radar instead of laser for speed measurement. It occured to me that graphite absorbs microwaves very well [sciencedirect.com], and might be used as a paint pigment, and be toning down the highly reflective areas by changing the shape before painting a car might be almost invisible to radar..

Re:I would have never guessed... (0)

Anonymous Coward | more than 3 years ago | (#32614656)

The RF is bouncing off the sides of the car and is not returning to the receive antenna. Just cover your car with flat sheets of metal and avoid any square corners and a cop is going to have to be at just the right place to get a signal back. Look at stealth aircraft and note how flat every surface is. That's worth far more than any absorption. Or just get a radar detector. You'll get plenty of warning. Pop-up radars are pretty rare.

That comforting green glow (3, Funny)

seniorcoder (586717) | more than 3 years ago | (#32612848)

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.

Re:That comforting green glow (1)

biryokumaru (822262) | more than 3 years ago | (#32612952)

No matter how much we tweaked it, we couldn't get the undergrad coeds to do the second part without the first one. Oh well, I guess we can live with Orion slave girls.

Re:That comforting green glow (0)

Anonymous Coward | more than 3 years ago | (#32613032)

Hey, were you that creepy guy I saw trying to hitchhike a couple weeks ago? I just wanted to tell you that, as I passed you, the saddest music was playing on the radio.

Still, get a car mr. smarty pants.

Re:That comforting green glow (3, Funny)

capt.Hij (318203) | more than 3 years ago | (#32613134)

After years of monitoring postings across the net I have finally found you. I knew the internet would be your weakness, and you would slip up. Now, I will hunt down your ip address and finally bring some small measure of justice to this world.

--Thunderbolt Ross

Re:That comforting green glow (1)

noidentity (188756) | more than 3 years ago | (#32613674)

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.

Which part did you find strange?

Re:That comforting green glow (0)

Anonymous Coward | more than 3 years ago | (#32614406)

Please aim your device at Salma Hayek.

Thank you.

Old? (2, Informative)

b00fhead (669286) | more than 3 years ago | (#32612894)

This seems to be from 2006/7...

Re:Old? (0)

Anonymous Coward | more than 3 years ago | (#32612920)

yea and it was on hack a day ... yesterday

good job slashdot, I came here to read the news, but not from yesterday

Re:Old? (4, Informative)

stewbee (1019450) | more than 3 years ago | (#32613074)

You're right. I know the author of the slides. This was part of his PhD disertation. He graduated about 2-3 years ago. He just recently posted the "how to" on his blogspot page this week.

Re:Old? (-1, Offtopic)

dsoltesz (563978) | more than 3 years ago | (#32613150)

There's a couple links in the Pubs section that are recent (May and June 2010), but I'm not really certain those pubs add anything new to the content. I'm now beyond disappointed in Slashdot: breaking news posted hours after it stop being relevant; other news stories sometimes showing up a week later after the furor has passed, and everyone's forgotten about it and moved on; and now, news that is 3+ years old. Wow. Why am I here?

Re:Old? (1)

biryokumaru (822262) | more than 3 years ago | (#32613288)

Why am I here?

Because even with stale topics to talk about, GNAA nonsense and completely offtopic rants, the comments here are an order of magnitude better than any other news site out there.

A lot more than 240 (5, Informative)

apepooooop (777854) | more than 3 years ago | (#32612926)

"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 [ni.com] With a $700 (not counting accessories) data acquisition card.

Re:A lot more than 240 (3, Informative)

chill (34294) | more than 3 years ago | (#32613164)

$150 to $450 on EBay, but still your point is valid.

The point isn't the specific price (2, Interesting)

weston (16146) | more than 3 years ago | (#32617648)

$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...

Re:A lot more than 240 (2, Informative)

Alex Belits (437) | more than 3 years ago | (#32613360)

Not counting computer, Windows, Labview and Matlab.

If anything, someone concerned with the cost would try to exclude the last two, as they alone make it more expensive than "high-cost" radars.

Re:A lot more than 240 (1)

MoonBuggy (611105) | more than 3 years ago | (#32613724)

OTOH, someone in a university environment is quite likely to be covered by site licenses already on those two, thus making the effective cost zero.

Re:A lot more than 240 (2, Interesting)

Alex Belits (437) | more than 3 years ago | (#32613846)

Someone in a university usually can just get a radar from the university. That doesn't mean, he can proclaim that he invented a zero-cost radar.

"GOSTATE in pushpins" (1)

4D6963 (933028) | more than 3 years ago | (#32612962)

Am I the only one who read "GOATSE with pushpins" and thought that it sounds a lot more painful than the regular goatse?

DIY portal gun next? (0)

Anonymous Coward | more than 3 years ago | (#32613020)

I'll wait for the DIY portal gun thanks :)

I would have RTFA (1)

sdturf (968920) | more than 3 years ago | (#32613130)

but I did not feel like getting a headache like I always do reading webpages with white text on a black background.

Re:I would have RTFA (0)

Anonymous Coward | more than 3 years ago | (#32614434)

View -> Use Style -> None

Your Browser May Vary

$240 for them, but not for me (2, Informative)

coolsnowmen (695297) | more than 3 years ago | (#32613144)

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.

Re:$240 for them, but not for me (1)

RealErmine (621439) | more than 3 years ago | (#32613430)

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.

Agreed. This is $240 only if you happen to have thousands of dollars worth of the right junk and test equipment lying around.

Re:$240 for them, but not for me (1)

lewiscr (3314) | more than 3 years ago | (#32618682)

Start your collection now. Then you'll have it ready when you want it.

I wonder how uncooked popcorn looks? (0)

Anonymous Coward | more than 3 years ago | (#32613366)

Let’s get old junk and put it all together in a university lab with (essentially) unlimited resources and see if we can build something. ( of course half a lifetime of physics and engineering study doesn’t hurt)

Re:I wonder how uncooked popcorn looks? (0)

cheezegeezer (1765936) | more than 3 years ago | (#32613474)

This is just about the level of comment i expect to see from slapshotters these days someone puts an article of interest up and the idiots crawl out of their coffins instantly to slam it down what a bunch of derranged tossers , I seriously believe this site needs closing down shipping out of the USA and starting again it may then become worthwhile and not be run/modderated by a bunch of idiots that slate worthwhile articles off yet praise the cobblers comments that appear maybe a little too much ganga or Amphet

 

SAR is really cool (2, Interesting)

Anonymous Coward | more than 3 years ago | (#32613438)

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.

Re:SAR is really cool (1, Informative)

Anonymous Coward | more than 3 years ago | (#32613628)

Found it: http://spectrum.ieee.org/computing/hardware/winner-radio-eye-in-the-sky

Old stuff (1, Interesting)

Anonymous Coward | more than 3 years ago | (#32614324)

I did this exact thing in 1984 in grad school for MSEE. Only it didn't require quite as much hardware as he used.

At the time it was hush-hush because it was for Air Force to use on new bomber construction - B1 with stealth-like attributes.

Cost more too. May have to revisit now that can find cheap parts.

Ho-Hum (1)

hoofinasia (1234460) | more than 3 years ago | (#32614336)

God bless the Can-Do attitude at MIT (and elsewhere, I suppose). I wish they hadn't thrown my application away, and hope that the totally-awesome-just-not-MIT school that I'm going to will support this kind of thing.

AWESOME fP... (-1, Offtopic)

Anonymous Coward | more than 3 years ago | (#32614638)

they want you to Name on the jar of FreeBSD continues The cuRtains flew are allowed to play tossers, went out what provides the Consider worthwhile or make loud noises

Got all the microwave parts at hamfests? (2, Interesting)

Animats (122034) | more than 3 years ago | (#32615006)

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.

Re:Got all the microwave parts at hamfests? (2, Informative)

stewbee (1019450) | more than 3 years ago | (#32615660)

I actually know the author and I know how he came across the Bridgeport and test equipment. First, I will say that he did his PhD work at Michigan State, not at MIT. He does work for MIT Lincoln Labs, hence the MIT moniker everywhere. He acquired his test equipment usually from things like the Dayton Hamvention. I even picked up an oscilloscope myself there for about $50 when I went with him one year. As for the Bridgeport, he know of a machine shop that was getting rid of two Bridgeports. I think he offered them a small sum of money as long as he came to haul them away. Him and and another friend of mine then became owners of their very own milling machines.

However, I will admit that this is certainly beyond the capabilities of most people due to the lack test equipment that is needed to even test the parts found at the swap meat.

Re:Got all the microwave parts at hamfests? (2, Funny)

bugs2squash (1132591) | more than 3 years ago | (#32616184)

A swap meat sounds like the kind of place one would go to find an organ donor, not a radar.

Re:Got all the microwave parts at hamfests? (0)

Anonymous Coward | more than 3 years ago | (#32617590)

A swap meat sounds like the kind of place you'd look for sausages.

Re:Got all the microwave parts at hamfests? (1)

Animats (122034) | more than 3 years ago | (#32618024)

However, I will admit that this is certainly beyond the capabilities of most people due to the lack test equipment that is needed to even test the parts found at the swap meet.

True. Although it is easier to get gigahertz test gear than it used to be, the typical 'scope won't go there. [tek.com]

Cool Technology, but ... (1, Interesting)

Anonymous Coward | more than 3 years ago | (#32616312)

It's still amazing a humble little bat accomplishes essentially the same thing except with sound, especially given the computational resources fourier transformations require.

Now these points of data make a beautiful line! (0)

Anonymous Coward | more than 3 years ago | (#32617334)

(And we're out of beta; we're releasing on time!)

Load More Comments
Slashdot Account

Need an Account?

Forgot your password?

Don't worry, we never post anything without your permission.

Submission Text Formatting Tips

We support a small subset of HTML, namely these tags:

  • b
  • i
  • p
  • br
  • a
  • ol
  • ul
  • li
  • dl
  • dt
  • dd
  • em
  • strong
  • tt
  • blockquote
  • div
  • quote
  • ecode

"ecode" can be used for code snippets, for example:

<ecode>    while(1) { do_something(); } </ecode>
Sign up for Slashdot Newsletters
Create a Slashdot Account

Loading...