Circle Irrigation is Cool!

Sometimes when flying over the middle states, you might see something like this:


Some of the more comedic then say “Look! Crop Circles!” Well, yes, they are crops, and they are in circles, but these aren’t made of aliens. If you got down to the ground to view them close up, you’d see something like this:

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So, how does that make the green circles? I’ve wanted to know more, and conveniently Destin at SmarterEveryDay just made this video that explains it really well:

Thanks for explaining all that Destin!

Necrobotics is using dead spiders as robotic hands

Spiders are awesome. If you’ve ever seen a dead spider you know that they curl up when they die. They do this because that’s the normal position for the legs; to keep the legs spread out the spider pushes fluid into the legs, which straightens them. Yes, spiders use hydraulics.

So some enterprising engineering people at Rice University decided to use a syringe to actuate this hydraulic system. And she can use it to pick stuff up and put it back down. It turns out that dead spiders can be used as robotic claws. Neat!

Deeper than the Kola Superdeep Borehole, and lots of power to boot

For years I’ve been fascinated by the deepest humans have ever dug into the Earth. The Kola Superdeep Borehole in the Kola peninsula of Russia is over 12 km deep. It took 20 years to dig that far, and they had to stop because it was so hot down there (180 °C) that the rock was plastic and flowed, making drilling nearly impossible. The project was stopped in 1995.

But it looks like scientists may have found a way to dig deeper holes, and use the great heat down there to generate power. We’ve been using geothermal power for a long time, but it hasn’t been feasible to do in where the surface crust isn’t hot. The really interesting thing is the way we may be able to drill deep, down to where it’s 500 °C.

Quaise, a spinoff from MIT, has a way to use millimeter-wave beam technology to easily and quickly break even the hardest rocks. They claim to be able to complete a 20 km deep hole in just over 100 days.

If this works (and that’s still a big if), it could lead to reliable geothermal power, without requiring CO2 emissions after the hole is dug. They’re looking to have a 100 megawatt geothermal plant operating in 2026.

Music for Oscilloscopes

First, a story:

Many moons ago, before laser pointers were things you could get at your local convenience store for the cost of a few packs of gum, back when lasers were expensive and cool, my friend got a laser. I’m pretty sure it was discarded by some lab. It was a tube about 5 cm in diameter and about 30 cm long and had a large brick-sized power supply. It was fun to play with, but ultimately it’s just a laser making a red dot on the wall. So Phil, for that was my friend’s name, took a speaker from his stereo, and taped a small mirror to the cone. Then, with the lights out, aimed the laser at the mirror and played music. Suddenly, the music came alive on the ceiling where the laser was being reflected. We called it Philsarium, after Laserium, which had been shown in the 1970s at planetariums.

That’s it for the story. Not much of a moral, I admit, but it was more of a trip down memory-lane. Anyway, the reason I bring it up is this week I saw a certain Smarter Every Day video. This video immediately brought that experience back to mind, except this time the laser is replaced by an oscilloscope. Oh, and instead of using regular music, awesome people in Austria craft music specifically to show different things on the oscilloscope. What normally shows sine waves or square waves (or RS-232 signals that Phil and I had to reverse engineer at one point) now shows everything from Tetris blocks to Tyrannosaurus Rexes.

Like Phil’s laser, the oscilloscope also shows a dot. Normally it shows various waveforms for analysis, but really it just shows voltage visually. By splitting the music’s stereo signal into 2 lines (one for the left speaker, the other for the right) and connecting these 2 voltages to the oscilloscope’s two inputs, the oscilloscope’s dot can be moved around the screen based on what the music does. One input (say the left audio channel) controls the horizontal, and the other input controls the vertical, moving the dot around the screen. By adjusting the voltage for the two channels carefully, you can turn the oscilloscope into an Etch-a-Sketch. And by having the sound change the drawing changes, and you can move and change the image. OK, it may be a long way to go for what is today considered mere music visualization, but doing it on a ‘scope is brilliant.

Those wacky Austrians have made albums of music based on this. The music is constrained by it’s primary audience, the oscilloscope, so it sounds somewhat like raw old school synthesizer music.

There’s a lot of trigonometry involved in this, so the next time a student asks a math teacher “when will we use this”, the answer may be “when you form a band.”

Robots with blood?

You have blood. Your dog has blood. Heck, spiders have blood (hint: it’s clear). And now so do robots.

Would you believe that a robotic fish has blood that is used for both hydraulics and energy? Well there is one. It looks like a lion-fish. And using this special blood instead of batteries let it last up to 8 times longer.

You can read lots more about it here, at Nature.

A plane with no moving parts

That is, no propeller, no turbines, no elevators, etc. Nada. Zilch.

OK. You and I have made airplanes like that: paper airplanes. But what about a plane that is self-powered, but still doesn’t have any moving parts? Well, MIT made such a thing, and it doesn’t even need black magic.

They use high voltage wires in front of and behind the wings to strip electrons off of nearby air molecules, and then pull those molecules to the rear. This “ionic wind” generates enough thrust to power the aircraft.

Granted, the plane itself only weighs 5 pounds, and didn’t fly far, but this is a pretty groundbreaking achievement.

Save lives for under a buck

A previous student of mine showed me this video, which actually ties in with something I had just found out about a few weeks previously. By combining a cheap, paper microscope that cost about $0.50 to make, and a child’s spinning toy, it is possible to diagnose malaria, which kills millions each year. The microscope is called the Foldscope. It’s printed on a heavy piece of die-cut paper, and then gets cut out and folded into a surprisingly powerful microscope, able to see blood cells. You can preorder these yourself (I have!). The other piece, the spinning toy, replaces expensive centrifuges to separate the blood into components. Coupled together (along with a doctor) you can do the lab work for diagnosing malaria for under $1.