Archive for July, 2014

Anyone else there loved the X Files (at least during the first few seasons, before it became a closed loop ..)? I think I particularly enjoyed the first season, because every episode was a reference to some B-series horror movie. I think they made at least two approaches to Carpenter’s The Thing and one of them was Firewalker:

In this episode, some volcanologists go missing during an expedition and an exploring robot sends some creepy video feedback that caught Mulder’s flimsy attention. I’m not going to focus on the X File itself, but instead on the robot inside the volcano. Basically, because it is as real as it gets.

firewalker

If I recall the episode correctly, the robot in X Files was similar to italian Robovolc, which is an all terrain research robot funded by the European Union ICT program from 2000 to 2004. Robovolc, however, was just expected to explore volcanic areas, not to go inside the crater. The tracks were appropriate to move on lava flows, ash and spatter cones and large ground fractures, but if the robot rolled over inside the volcano, it would be over for it and recovery might be tricky at the very least in such an environment.

Robovolc

Reportedly, the best robots to cope with uneven terrains when rolling over may become a serious issue are legged ones (or mesh robots, like Tet-Walker, but those are still on the design table). In here, for example, one can watch Big Dog fall, roll over and get on its (4) feet again. This skill is crucial if a robot is meant to be dropped on parachute over a dessert or, case in hand, rappelled into a volcano.

Dante-cover (1)

Dante was developed in spider shape by the NASA precisely to roam a volcano from the inside and send video feedback home. Also as a local test for alternative planet explorers to Sojourner, Spirit and Opportunity, one would guess. Needless to say, Dante was christened after the Divine Comedy, since it was supposed to descend into hell.

Using its tether cable anchored at the crater rim, the robot descended into craters to gather and analyze high temperature gasses from the crater floor. Exactly like in the X Files episode. Furthermore, Dante I was built at Carnegie Mellon University around 1992, so the writers of the show probably used it as reference. In 10 months, Dante I had descended into an active volcano, Mount Erebus, in Antarctica. Eventually, the communications tether failed and the mission ended prematurely after only 20 feet, but the robot actually worked. Indeed, CMU developed Dante II, a second tethered walking robot, which explored the Mt. Spurr (Aleutian Range, Alaska) volcano in July 1994. Dante II worked fine (660 feet into the crater) until crashed by a huge rock on its way out. Given that the $1.8 million project remains buried there, it is comprehensible that they did not try again, even though these robots were pretty awesome.

Later experiments like RoboVolc or rackWalker-II settled for out-of-the-volcano exploration Maybe in a future smaller/cheaper spiders can be developed to go inside again. Unfortunately, there are two main problems to do smaller volcano-exploration robots: i) smaller legs can not cope with large obstacles like rocks and ground fractures; and ii) the equipment required to analyze gas and chemicals and to gather samples tends to be bulky. In the meantime, we have to settle with Dante’s videos 😦

 

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Anyone recalls that Futurama episode where Professor Farnsworth builds a Smell-O-Scope to search the galaxy and Jupiter smells like strawberries? Turns out it’s not such a crazy idea. In fact, scientists from the Max Plank Institute used the IRAM radio telescope in Spain to study a dust cloud near the center of the galaxy and, guess what? it smells like raspberries … and rum. Yummy! I knew I liked astronomy for a reason.

 NASA JPL/Caltech/Univ. of Wisconsin

Apparently, the chemicals they found in those clouds include ethyl formate, the dominant flavor in raspberries and a key one in rum, although there are other molecules that might mess up with the smell.

Of course, scientists do not actually smell those clouds: they identify the chemicals and map them into familiar earth compounds just to explain what they’ve found. One would think — booo-riiing. But we could actually very well build a smell-o-scope under these premises.

In 1932 Huxley’s book Brave New World, he proposed full sensory movies called “feelies”. The key idea is that smells are due to volatile molecules called odorants that constantly evaporate and reach our olfactory receptors. In the early 1950s, Hans Laube actually created the Smell-O-Vision, by pumping into tiny tubes spread around a theater a combination of 30 different smells including flowers, garlic, smoke, oranges, etc.  The process had to be steadily controlled to avoid residual smells and the concept did not catch.

Nevertheless, half a century later, there is still people working on smell interfaces, like Meta Cookie or the Smelling screen. The idea is the same (odorant containers released in a sequence) but systems are more portable. So, in theory, if we identify some molecules in a far away galaxy, we can release LOCALLY the smell that they are supposed to yield straight to the observer’s nose.

Now, on a smaller scale, believe it or not, Denver cops have been using what they call Nasal Ranger Field Olfactometer since they legalized marijuana to enforce the so called “odor-ordinance”. In this case, the device indeed enhances smells so they can be detected at 500:1 ratio. This works as long as one is within the smell source range, so no raspberries for us – duh

Anyway, all in all, if one combines whatever the telescope finds with a smell interface … duh, Smell-O-Scope, everyone. If it’s in Futurama, it’s technically sound 🙂

More on the raspberry-er Center of the Galaxy (The Guardian)
More on Smell Interfaces (Sensoree)
More on Olfactometer (St Croix Sensory)

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Today, and just because I’m reading (better late than never …) Kurt Vonnegut’s Cat’s Cradle and it’s hot around here these days, we are gonna cover one of these do-it-yourself experiments that never seem to work for me, yet there they are …

One of the leading threads in this (awesome) novel is Ice-Nine, the hidden, most lethal creation of the nuclear bomb father Dr. Felix Hoenikker. I’m not going into further detail on the plot, in case someone has not read it and wants to. The idea behind Ice-Nine is to help troops move around swamps and muddy landscapes by dropping a tiny fragment of the substance inside them. Automatically, all water in contact with the fragment would become Ice-Nine as well and soldiers could move easier. 

In the book, Ice-nine is a polymorph of water more stable than common ice that melts at 45.8 °C. As soon as a chirp becomes in contact with any liquid water below that temperature, it acts a a seed and solidifies the entire body of water. Ice-Nine obviously doesn’t exist -one hopes- but this idea is based on a very real phenomenon known as supercooling. Indeed, Vonnegut gives credit for the idea to General Electrics scientist Irving Langmuir, who reportedly invented the trick to entertain H.G. Wells during a visit to GE. 

Impressed? Here’s a tutorial on how to do it yourself, although it might take some practice to get your water at the precise correct temperature. The key idea is to bring your bottled water down to a temperature where it’s about to freeze … just not there yet. This process is called supercooling (or undecooling). At this point, homogeneous nucleation (which leads to crystallization) has not ocurred yet, and the water is an amorphous solid. To avoid homogeneous nucleation, the water must be as pure as possible.

At this point, the supercooled water is ready to freeze as soon as it touches a seed, i.e. a piece of ice, and … voila, instant ice.

 

subcooling water

 

So differences with Ice-Nine? Fortunately, there are many. For starts, the supercooled thing would need to be the large body of water we want to freeze, not the chirp of ice in our pocket. Total pureness is not likely to be a property in any body of water outside a lab too. Most important of all, supercooling works at 0ºC, not at 45.8ºC (a temperature threshold that grants that we could freeze almost all the world on a whim).

In fact, a Ice-IX does indeed exist, but has none of Vonnegut’s Ice-9 properties. The closest call would be the so called disappearing polymorphs, a type of crystals that, introduced in an environment, replace local crystals with their own form.