NASA has successfully demonstrated a manufacturing technique that will allow the creation of large, commercial hybrid flying wing aircraft. These planes would use half the fuel of conventional, tubular jet airliners, and would provide a quieter ride for passengers on board.
In general, there are four plane shapes: A tube with wings, a blended wing body, a hybrid wing, and a flying wing. The last three ditch the tube in favor of a much flatter chassis with an almost-rectangular cross-section. The advantage of these designs is that the body actually acts like a wing, adding extra lift. The down side is that flying wings are less stable (they lack a tail), and the rectangular cross-section makes it a lot harder to build a light fuselage that can withstand the rigors of pressurized air flight.
Aerospace engineers have long been aware of the advantages of flying wing aircraft — reduced weight, and drag, and thus higher top speeds and lower fuel consumption — but it has so far proved impossible to build a flying wing that’s large enough to transport hundreds of people in comfort. There are dozens of flying wing designs in use by the military, but these are generally small aircraft that don’t need to worry about the comfort of the soldiers on board. The Northrop Grumman B-2 Spirit (Stealth Bomber, pictured above) is probably the best-known example of a hybrid flying wing aircraft.
Now, NASA is reporting that it has devised a manufacturing method of producing hybrid flying wing aircraft that is large enough for commercial travel. The method starts with carbon composite rods, which are then covered with carbon fiber fabric. Foam strips are placed between the rods, and again carbon fiber is stitched onto them, creating structural crossmembers. The carbon fiber fabric is finally impregnated with an epoxy resin, turning the whole thing into a very rigid structure when it sets. All told, this new technique can reduce the weight of an aircraft’s structure by 25%.
In testing, fuselage parts made using this technique could withstand the necessary forces. The plan now is to build a 30-foot (9.1m), two-floor fuselage to see how the new manufacturing technique copes in situations that approximate real-world use. Eventually, 10 or 20 years down the line, NASA hopes that this manufacturing technique can be used to build commercial jets.

As Technology Review points out, a hybrid flying wing aircraft would also need a different kind of engine — something like an ultra-high-bypass engine. Ultra-high-bypass engines (aka propfans or unducted fans, pictured right) still use a “turbo” design, but have a large number of small, twisted propeller blades at the back — kind of like if you took a turbofan, but removed the housing from the back half of the engine. In NASA’s hybrid flying wing, these UHB engines would be mounted on top of the plane, reducing the noise inside the fuselage).
This hybrid flying wing is just one facet of NASA’s Environmentally Responsible Aviation (ERA) project, which was instigated in 2009 with the hope of reducing the impact of aviation on the environment. For more information, hit up the NASA website.

On 16:35 | 0 comments More

How exactly do you drive the one-ton Mars rover Curiosity, when the driver is, on average, 150 million miles away? With a one-way time delay of around 13 minutes, it certainly isn’t a matter of sitting down in front of a monitor and waggling a joystick.
While we’ve tackled just about every aspect of NASA’s Curiosity rover, from the radiation-hardened on-board computers through to its nuclear-powered laser, we’ve never really discussed navigation — a rather important aspect, as most of Curiosity’s two-year prime mission will be spent driving the few miles to Mount Sharp.
In short, there are two ways that Curiosity can navigate the surface of Mars: NASA can transmit a series of specific commands, which the rover then dutifully carries out — or NASA can give Curiosity a target, and then trust the rover to autonomously find its own way there. In both cases, the commands are transmitted to Curiosity via NASA’s Deep Space Network — the worldwide network of big-dish antennae that NASA uses to communicate with spacecraft, and carry out some radio astronomy on the side.
To decide which navigation method to use, NASA uses the Rover Sequencing and Visualization Program (RSVP), which is basically a Mars simulator. RSVP shows Curiosity’s current position on Mars, along with surface topology, obstacles (rocks), and so on. RSVP can then be used to plot a move (go forward 10 meters, turn 30 degrees right, go forward 3 meters) — or to pick an end point, which Curiosity will dutifully, autonomously navigate to. To safely navigate Mars, Curiosity uses its Hazcams (hazard avoidance cameras) to build a stereoscopic map of its environment, identifies which objects are too large to drive over, and then plots out a course to the end point.
When Curiosity finishes its drive, it transmits a bunch of thumbnail images from its on-board cameras to NASA, which are then used to work out Curiosity’s exact location on Mars. This data is fed into RSVP, the next day’s movements are plotted, and so on and on.

In other news, Curiosity is now deep within Yellowknife Bay, a shallow depression on the surface of Mars where NASA will hopefully find an interesting rock that will become the first victim of Curiosity’s percussive hammer. Yellowknife Bay is pictured above, along with the step (about 2ft high) that Curiosity had to cross to descend into the bay. Curiosity will spend the next few days in Yellowknife Bay, while the NASA/JPL engineers enjoy a long-overdue break, and then begin the long trek to Mount Sharp, which will probably take up most of 2013.

Finally, a beautiful bonus image — think of it as a Christmas gift from ExtremeTech. What you see above is Saturn, all of its rings, and its moons Enceladus and Tethys (bottom left). This unique image, which is a mosaic of hundreds of images, was captured by the NASA/ESA/ASI Cassini orbiter as it passed through Saturn’s shadow, roughly 500,000 miles (800,000km) from the planet. With Saturn between the Sun and Cassini, and the dramatic viewing angle, this is probably the best view of Saturn’s rings that you will ever see.
Cassini has only taken an image from the shadow of Saturn once before, in 2006 — and that time, Earth was visible (10 o’clock, at the edge of the rings).

On 05:38 | 0 comments More

If not for our brains, our eyes wouldn’t be able to process anything. Considering how much time we spend with our eyes open, our brains are constantly dealing with an influx of visual data. The brain needs to store that data somewhere, and thanks to scientists over at the University of California, Berkeley, we now have our first map of not only where the brain puts all that information, but how our grey matter organizes it.
The study (PDF), led by neuroscience doctoral student Alexander Huth, had five participants watch two hours of movie trailers that contained over 1,700 categories of actions and objects. During that time, their brain activity was recorded using functional Magnetic Resonance Imaging (fMRI), measuring blood flow in various spots in the brain. Using linear regression, the scientists were then able to analyze the collected data, and subsequently build a model showing how all of those actions and objects fit into around 30,000 locations within the cortex.
After that point the researchers translated the model to a visual form. Using principal component analysis – a mathematical procedure used to provide a synopsis for a large amount of data — the scientists were able to visualize those 1,700 categories and how they related to one another, creating the chart shown to the right.
The map is made “semantic neighborhoods,” which are essentially just categories of things that the brain finds similar to each other. The researchers found that, for instance, the brain organizes the catefgories of “humans” and “animals” in a related manner, whereas “eyeball” and “car” are stored in completely different areas of the brain. Along with finding out how the brain organizes different categories of objects, the researchers also found out that different people’s brains organize things in similar ways.
The goal of the project wasn’t simply to make a pretty map, but to gain a more complete understanding of the brain, and how its visual and organizational processes function. This understanding could lead not only to a better diagnosis and understanding of brain disorders, but could help create a new interface between a brain and computer, sprucing up image recognition systems. Huth notes that the results of the study could help “label an image that someone is seeing, and may also help teach computers how to better recognize images.”
Going one step further than simply conducting and writing up a study, Huth and co. have created an online, interactive semantic map of the brain that anyone can access, provided your browser doesn’t crumple under the weight of WebGL. Check it out — you can slowly pull a brain apart with a slider!
Now read: First map of the human brain reveals grid-like structure between neurons

On 20:19 | 0 comments More

Share This article

3
inShare

In one of the last updates before the Large Hadron Collider (LHC) shuts down until 2015, CERN has announced that its observation of the Higgs boson (or a particle that is Higgs-like) is now approaching 7 sigma certainty.
5 sigma — 99.9999% certainty, or more correctly a 0.00001% chance that you have made a faulty observation — is the threshold for an observation to be labeled a scientific discovery. CERN crossed the 5 sigma threshold this summer. At 7 sigma, both the CMS and ATLAS teams are reporting that there’s only a 0.0000000001% chance that they haven’t found a Higgs-like particle.
Over the last few months you may have noticed the use of the phrase “Higgs-like,” rather than “Higgs boson.” This is because CERN and the scientific community can’t be certain that they’ve actually found the Higgs boson — all they know is that they’ve found a particle, with a mass of around 125 GeV, that behaves as predicted by the Standard Model of particle physics. With its discovery now completely and utterly confirmed, further analysis (due in 2013) will now focus on the particle’s spin, and other properties. Eventually, perhaps after upgrades are completed and the LHC turns back on in 2015, the particle will be officially announced as the Higgs boson (or not, which would be much more interesting).

In other news, CERN says that it has observed the decay of the B_s meson (strange B meson) into two muons. Apparently this is one of the rarest processes ever observed in particle physics, which means it’s a good chance that it could lead to new science.

On 17:33 | 0 comments More

Faux Metal Tesla Turbine

   This instructable is a continuation of a post from 2011 (http://www.instructables.com/id/Machining-a-Mini-Tesla-Turbine-from-Cardboard/). The Cardboard Tesla Turbine (CTT) was based on a Popular Mechanics article describing the construction of a steam-powered, metal turbine that was published nearly 50 years ago. A year later, I've added spray painting and detailing tips as well as some disappointing results when attempting to power the CTT using a cartridge of compressed CO₂. I chose colors to create the appearance of precision machinery crafted from brass, copper and titanium alloy. The rotor discs were painted to resemble a carbon fiber composite of high tensile strength.

   The original project was made from closely spaced, cardboard discs centered on a threaded steel rod. The rotor assembly was suspended in a bathroom tissue role by a supporting assembly. The aviation grade bearings were housed in retaining assemblies. When a stream of air from an electric air pump was injected into the manifold, the stream spiraled inward between the discs toward exhaust ports surrounding each disc's center. The stream exited the turbine along the axis of rotation. Peak rotor speed was measured at 2,220 RPM. Note that the following instructable assumes that you have a fully functioning CTT that is ready for painting and customizing.

Warning 
   Anything attached to the rotor shaft could fly off suddenly if not properly secured. In addition, the sudden decompression of CO₂ as the gas escapes from the cartridge produces extreme cold. Use heavy gloves when handling the cartridge.
    

Remove these ads by Signing Up

Step 1: Items You Will Need

Supplies
300 Grit Sandpaper
Ceramcoat All Purpose Sealer (http://www.deltacreative.com/pcid/86/Tips-Technique.aspx) or something similar
Hobby Paint Brush
Letter Stencils

Paper Tape
Silver Marker Pen
Spray Paints: Black, Blue, Brass, Clear Enamel, Copper & Silver
Spray Paint Safety Mask

Tools
Popsicle Sticks to Use as Rotor Shims (4) - 1.5 mm thick
Sanding Block
Scissors
Screwdriver

Misc
25g Threaded CO₂ Cartridges w/Regulator (http://www.innovationsaz.com)
38 cm plastic zip ties (2)
Plastic Propeller & Mounting Hardware
Working CTT

On 16:55 | 0 comments More

Buffeted by ethereal whirlwinds and twisters, the Curiosity Mars rover is wrapping up initial soil analysis operations at a sandy drift where it's been parked for more than a month, project scientists said today. The rover is now being prepared to move on in search of suitable targets for a compact rock drill, the final major sample acquisition system to be tested.
Ashwin Vasavada, the deputy project scientist for the Mars Science Laboratory rover at the Jet Propulsion Laboratory in Pasadena, Calif., told reporters that Curiosity's robot arm had completed five scoops of martian soil, using the sandy material to clean and scour the sampling system and to deposit samples into both of the rover's main internal instrument suites.

Scoop marks can be seen in a sand bank where the Curiosity rover has been collecting soil samples.

(Credit: NASA)

The Chemistry and Mineralogy package, or CheMin, uses X-ray diffraction to identify and analyze the minerals in samples collected by Curiosity's robot arm. The Sample Analysis at Mars, or SAM, package, uses a suite of three laser spectrometers to look for signs of organic compounds, a key element in the rover's search for signs of past or present habitability.
CheMin analyzed its first soil sample earlier while SAM initially was used to analyze samples of the martian atmosphere, in part to look for signs of methane. While earlier Earth- and space-based observations indicated methane might be present, Curiosity's initial results found no clearly measurable amounts at the Gale Crater landing site.
Vasavada said Thursday SAM now is processing its first soil samples and "based on a very brief look at that data, the team decided to run a couple of more SAM experiments, which are customized to this particular soil and we're currently in the midst of getting those results back."
"The rover really is doing incredibly well," he summarized. "We've had very, very few glitches to speak of... as we run this very complex piece of technological machinery. There's also the human side of it. The team also has been working very well. We have a lot of different protocols to make sure we don't make mistakes. We have to learn a lot as we operate this thing."
Curiosity landed in Gale Crater on August 6 and after initial tests and checkout, flight controllers directed it to an area known as Glenelg, where orbital photographs show three different rock and terrain types coming together.
For the past 40 or so martian days, Curiosity has been parked by a sand dune, collecting soil samples and giving the flight control team a chance to learn the intricacies of remotely operating the complex sample acquisition system.
Vasavada said engineers now are making plans to resume driving in a bid to find a suitable rock for initial drilling tests. That process is expected to take a month or more to complete.
"We're pretty excited," Vasavada said. "After more than 40 sols (martian days) being parked in front of this sand drift, we're actually going to start moving again. Frankly, the team is pretty excited about that even though it's been a wonderful campaign to analyze the soil."
In the next few days, he said, "I think you'll see us head on to our next site. We still would like to get a little further into this Glenelg region where we see this diversity of rocks and layered rocks and other really interesting terrain. And then we still have a goal in the next month or two of doing the big U-turn and heading up to Mount Sharp."
Mount Sharp is a 3-mile-high mound of layered terrain in the center of Gale Crater where Curiosity is expected to spend the bulk of its planned two-year mission.

Data from the Curiosity Mars rover shows sudden changes in wind direction and pressure, indicative of a twister passing nearby.

(Credit: NASA)

In the meantime, the science team is having a field day with Curiosity's initial observations, including an ongoing analysis of the martian weather.
"Most of what we've talked about on this mission is the ancient habitability of Mars," Vasavada said. "But we also have some pretty important goals on this mission of studying the modern environment. And it's a pretty dynamic environment.
"If you were standing next to Curiosity, you'd realize you were on a planet with an atmosphere, an atmosphere that's thick enough that when the sun heats the ground every day, gusty winds rush up and down the slopes of Gale Crater and Mount Sharp and spawn whirlwinds that sweep across the landscape. But the atmosphere isn't thick enough to shield you from the harsh ultraviolet light and the natural high energy radiation coming in from space."
Manuel de la Torre Juarez, a co-investigator with the Rover Environmental Monitoring Station, or REMS, aboard Curiosity, said wind data indicates nearly two-dozen twisters, or dust devils, have nearby or directly over Curiosity.
But that's based on wind speed and direction data alone. The rover's cameras have not yet spotted any such twisters.
"Dust devils on Mars have been seen in missions before," he said. "We have images from previous rovers. Although we've been trying to find them here, we haven't gotten any imagery yet. But we have been able to measure all the environmental variables associated with dust devil activity."
The data show sudden changes in pressure and wind direction that are indicative of twisters. But Juarez said the whirlwinds would pose no threat to astronauts.
"The martian atmosphere is a very low-density atmosphere, the pressures (are what) you would have if you were flying at twice or three times the usual airplane height," he said. "So it would have almost no push on you. It might obscure your vision if it lifts dust, and that's what we're looking for. We're seeing all the signatures, but we're not seeing dust being lifted yet.
"These events are starting to occur more and more often. We have measured 21 thus far, but we are still out of the season where they occur. We expect to see more in the future."
Along with keeping tabs on the weather, another instrument aboard Curiosity is monitoring the radiation environment, a critical factor for engineers contemplating future manned missions.

Radiation levels on the surface of Mars go up when atmospheric pressure goes down, decreasing when the pressure rises.

(Credit: NASA)

Don Hassler, principal investigator for the Radiation Assessment Detector, or RAD, said radiation levels at the surface vary daily, rising when atmospheric pressure drops and decreasing with the pressure goes up.
"Basically, we're finding that the Mars atmosphere is acting as a shield for the radiation on the surface and as the atmosphere gets thicker, that provides more of a shield and therefore we see a dip in our radiation dose," he said. "This dip is on the order of 3 to 5 percent and it's very reliable, we see it every day."
But he said it's too early to draw any conclusions about what sort of shielding future astronauts might need, in large part because the effects of major solar storms are not yet known. While Earth's magnetic field acts as a protective shield during solar storms, Mars has no such protection.
"The astronauts can live in this environment," Hassler said. But the big question is how much radiation will an astronaut receive during an eight- to nine-month voyage to Mars, a six-month stay on the surface and then the long flight back to Earth.
"When you add up all those different contributions, you need to stay within your career limits," he said. "So over time, we're going to get those numbers. Since we've been on the surface, we have not yet seen a large solar flare or solar particle event like we saw during cruise (to Mars). When we do see one, that will be very interesting and very important."

On 17:07 | 0 comments More

With radiation levels on Mars apparently safe, how long will it be before astronauts start exploring the 'Total Recall' planet?

(Credit: TriStar Pictures) "Now, this is the plan. Get your ass to Mars."
We all remember Schwarzenegger motivating himself to go to the Red Planet in "Total Recall" (anyone bother watching the remake?) and sure we'd like to go too. Now NASA's Curiosity Mars rover has determined that radiation levels on the planet's surface are safe for human explorers.
"The astronauts can live in this environment," Don Hassler, principal investigator on Curiosity's Radiation Assessment Detector instrument (RAD), told a news conference.
"Basically, we're finding that the Mars atmosphere is acting as a shield for the radiation on the surface and as the atmosphere gets thicker, that provides more of a shield and therefore we see a dip in our radiation dose," Hassler said.
The findings mark the first time that cosmic rays have been measured on the surface of another planet, and come 100 years after Victor Hess discovered cosmic rays on Earth by using a hot-air balloon.

Following Curiosity's landing on Mars in August, the rover's RAD device has measured radiation that's comparable to what astronauts experience aboard the International Space Station.
The robot explorer was also detecting radiation during its eight-month journey through space, and found levels were about double what they are on the planet.
Mars lacks a global magnetic field, and researchers believe this led to the loss of most of its atmosphere long ago under solar wind bombardment. RAD has found that as the remaining Martian atmosphere thickens and thins daily, radiation levels rise and fall by 3 to 5 percent.
Hassler added that the numbers he reported are preliminary and the data must still be calibrated. More precise information would help determine how much radiation astronauts would be exposed to during their journey to and from Mars as well as their stay.
"When you add up all those different contributions, you need to stay within your career limits," he said. "So over time, we're going to get those numbers. Since we've been on the surface, we have not yet seen a large solar flare or solar particle event like we saw during cruise (to Mars). When we do see one, that will be very interesting and very important."
Designing a spaceship with adequate radiation shielding for the long trip to the Red Planet is another matter altogether. Put Arnold in charge of that, I say.

On 17:05 | 0 comments More