Crash-Proof UAVs Fly Blind at MIT

Here's another great story from our friends at Popular Mechanics that looks at cutting edge research into drones that fly autonomously inside structures. That's something that until now could only be done (barely) by wheeled mini-bots. But as you can see from this report, engineers still have a long way to go.

It's not the most attractive spy bot, but the unmanned aerial vehicle hovering some 20 ft. away is doing its job. For now, that means staying right where it is, weaving ever so slightly under the weight of the webcam strapped to its back. There's nothing particularly interesting to look at with this UAV, a commercial four-rotor model that any RC hobbyist could put together. But no one is piloting this modified drone -- it's flying autonomously, stabilized a few feet above the floor of MIT's RAVEN lab. Like most of the aircraft tested here, this model is a puppet, receiving input not from onboard processors, but from a nearby computer.

As it continues to buzz in place, an array of 18 motion-capture cameras tracks the UAV, providing 3D positioning data to determine just how stable it is. Specifically, those baleful red cameras -- the same kind Hollywood visual effects teams use to transpose an actor's movements to a computer-generated counterpart -- are tracking the tiny Styrofoam balls attached to the drone. On the computer monitor, these balls show up in real time, mapping the UAV as a cluster of dots, swaying in midair. I'm somewhere between impressed and bored when the drone begins to drift. A second later and it slams into a plexiglass divider, as hard as a hockey player.

It will take some time to figure out why this little craft suddenly lost control. But that's the point of RAVEN, or Real-Time Indoor Autonomous Vehicle Test Environment, where geeks capture every flight -- and collision -- in painstaking detail. There are no accidents here, just problems that haven't been sufficiently analyzed. "RAVEN gives us the freedom to test whatever we can build," says Jonathan How, director of MIT's Aerospace Controls Lab. "And we can build wonderful things, even in 24 hours."

One of the researchers has done just that, and is now preparing to fly a drone that was redesigned, then cobbled together out of lightweight foam core. Of course, this isn't exactly the next generation of missile-packing Predators; the toylike creation in front of me, with its circular wing and miniature nose-mounted propeller, is more of a testbed than a prototype. All of the UAVs covering nearly every surface of this lab, from high-end RC planes the size of a small child to a store-bought flying insect produced by WowWee, are just tools to develop flight control algorithms for indoor robots.

As challenging as it is to make something fly itself, designing a drone that can function indoors is even harder. For an indoor UAV to meet all of the military's expectations, it would need to be able to fly into a building and find a suitable spot to perch and observe, all without relying on GPS contact. "The ultimate vehicle is a bat that you can download data from," How says. Bats have the ability to perch, plus echo location to detect obstacles, and the agility to keep from slamming into them.

At the moment, nothing in development can effectively pull off even one of these functions, much less all three. Researchers at Carnegie Mellon University, for example, are sticking to basic navigation, with a small robot helicopter that uses sonar and cameras to avoid bumping into obstacles while flying indoors. But the lab here has a novel approach: Instead of focusing on building better sensors or more powerful vehicle-mounted processors, researchers at RAVEN are fine-tuning the mechanics of autonomous aerobatics. The 18 motion-capture cameras provide a perfect sensing environment, and the dedicated computers in the lab, which communicate with the test drones via radio transmitters, provide the brainpower. "People might say our UAVs aren't autonomous," How says, "but in this environment, the entire system is autonomous."...

Read more on this story and other high-tech reports from our friends at Popular Mechanics.

-- Christian

Lessons From the Accidental Nuke Flyby

A great inside look at a Pentagon after-action report on that embarrassing nuke flub where the Air Force flew a couple doomsday weapons across the US without even knowing it.

Let's hope this report doesn't just collect dust on some general's shelf and that the recommendations are actually implemented.

From our friends at Popular Mechanics:

One might think that the United States' nuclear weapons -- the cornerstone deterrent in the country's arsenal -- would be treated with the utmost precision.

This comfortable illusion was shaken on Aug. 31, 2007, when crews loaded six live nuclear warheads onto a B-52 bomber and flew from Minot Air Force Base in North Dakota to Barksdale Air Force Base in Louisiana, cruising over the nation's heartland. Each warhead was 10 times more powerful than the atomic bombs dropped on Hiroshima and Nagasaki during World War II.

During the analysis of the incident by the Defense Science Board (DSB), released this month, the ugly truth came out: America's nukes are so neglected that they are stored alongside conventional missiles, with nothing but an 8.5 x 11-in. sheet of paper to differentiate the two. The last day in August, Air Force personnel loaded the nuclear warheads on a routine repositioning of weapons stocks, believing them to be cruise missiles.

The system of checks and balances has degraded to a point that six of the planet's most powerful weapons were missing for 36 hours -- and no one noticed until they had landed in Louisiana. "The process and systemic problems that allowed such an incident have developed over more than a decade and have the potential for much more serious consequences," the report warns.

So what can be learned by this near miss, and how can something worse be avoided?

1. No one Air Force command is solely responsible for taking care of nuclear weapons.

There are plenty of weapons systems and missions out there, and each one is more exciting and has a higher priority within the command structure.

The DSB report notes that, after the demise of Strategic Air Command, three operational Air Force commands took over the nation's nuclear weapons: ICBMs went to Air Force Space Command; bombers went to Air Combat Command, and Air Mobility Command retained ownership of the refueling portion of the bomber missions. That means that there is no one central place where the nuclear mission -- upkeep, training and such -- is the primary mission. So the nukes got lost in the post-Cold War shuffle.

Recommendations in the report include the establishment of an Assistant Secretary of Defense for Nuclear Enterprise to focus solely on nuclear missions. This person would report directly to the Secretary of Defense. The DSB report notes that the U.S. Navy, which handles nuclear missiles in its submarine fleet, has a system that keeps those weapons under one banner, "Strategic Systems Programs." It's commanded by a rear admiral, whereas in the Air Force the highest rank with a primary, daily focus on nukes is that of colonel. "While the attack submarines no longer routinely carry nuclear missiles, the submarine forces retain their nuclear legacy and nuclear focus," the report says.

2. Human error was at the heart of the incident.

The staff at Minot Air Field had neglected to follow procedure for the sake of saving time. The verification of weapons -- what kind, what warheads they carry, their armament status -- should take about 45 minutes, and be performed before anything else happens.

"But, over time, to speed the process, breakout and convoy crews had established a process of concurrent activity," the report states. "In this case, the breakout and convoy crew [at Minot] were connecting the trailer to the tow vehicle while the initial status verification was under way." The checks had become pro forma, and a near disaster slipped through.

Indeed, the gaff that allowed six nukes out over three major American cities (Omaha, Neb., Kansas City, Mo., and Little Rock, Ark.) could have been avoided if the Air Force personnel had followed procedure.

"Let's not forget that the existing rules were pretty tight," says Hans Kristensen, director of the Nuclear Information Project for the Federation of American Scientists. "Much of what went wrong occurred because people didn't follow these tight rules. You can have all sorts of rules and regulations, but they still won't do any good if the people don't follow them."

In fact, some see the incident as a way to draw attention to the importance of the job of babysitting nukes. "This review gave the Air Force the opportunity to improve on an already sound nuclear enterprise," says Col. West Anderson, vice commander of the 2nd Bomb Wing at Barksdale AFB in Louisiana. "We handle weapons safely and ensure the highest possible standards of individual reliability and professional competence."

Read the rest of the story from our Popular Mechanics parters at Military.com

-- Christian

NASA Moon Mission in Jeopardy

NASA's current plan for manned space exploration focuses on establishing a base on the moon, as a vital steppingstone for a visit to Mars. The initiative has been trumpeted by the Bush administration, which wants the first mission to launch by 2020. But trouble is brewing as a growing group of former mission managers, planetary scientists and astronauts argues against any manned moon mission at all. One alternative, they say: Send astronauts to an asteroid as a better preparation for a Martian landing.

The dissenters gathered at a meeting of the Planetary Society at Stanford University. "We want to get a positive recommendation to the new administration," says Planetary Society executive director Louis D. Friedman. He supports an eventual mission to Mars, but argues that the current moon scheme was selected with inadequate debate after a speech by President Bush in January 2004. "If you said ‘humans' and ‘Mars' [to NASA officials] in the same sentence, you would receive a figurative slap on the face, and then four months later [the moon-to-Mars plan] was the main point on a viewgraph at the highest levels."

A recent article in Aviation Week reporting on the views of the meeting organizers drew a sharp reply from NASA administrator Michael Griffin. Griffin issued a letter defending the agency's Constellation lunar base program. "The conference organizers have assigned sole responsibility for our new civil space exploration strategy to President Bush, ignoring the hugely bipartisan -- actually nonpartisan -- support it has received in Congress," Griffin wrote. "No such far-reaching proposal should be adopted without debate. That debate was had, in 2003, '04 and '05, and it was fulsome. From it came a unifying plan for civil space, and the best legislative guidance NASA has ever had."

When asked in an interview with Popular Mechanics last year whether he thought the next administration might make manned missions a lower priority, Griffin insisted that he couldn't "imagine any U.S. president or any U.S. Congress deciding to take the United States out of the business of human space flight."

The lunar program, which was largely meant to reinvigorate NASA and renew public enthusiasm for space exploration, has suffered from a spate of bad press. Last week, the Associated Press reported that NASA's Ares I rocket, the replacement for the space shuttle, could literally shake the lunar hardware it carries to pieces during launch. Some presidential candidates have weighed in, criticizing NASA's current plan.

NASA does have vocal supporters, however. Robert Walker, a former congressman and a member of the Presidential Commission on the Implementation of the United States Space Exploration Policy, points out that a Chinese moon program has already begun, with the launch of a probe in 2007. Both India and Japan have also announced their intentions to launch manned lunar missions, to great fanfare.

"Having a U.S. presence on the moon at least gives us the chance to keep an eye on the standard of conduct," Walker says. "And that's pretty damned important." In military terms, the moon can be seen as the ultimate high ground. A nation could set up hard-to-defeat microwave or laser weapons platforms aimed at in-orbit satellites or, in the best sci-fi tradition, to launch large rocks at the Earth with "mass drivers." (These were the weapon of choice for Robert Heinlein's revolutionary protagonists in The Moon Is a Harsh Mistress.)

Read more on this story, the spy satellite shootdown, underwater terrorism and what the dark side of Mercury looks like from our friends at Popular Mechanics.

-- Christian

Radar Tech Could Shift Military Might

This month Lockheed Martin released a 280-word statement from its radar research headquarters in New Jersey announcing a breakthrough test of an advanced radar platform. And while the tech world shrugged, people watching the evolution of radar saw another step for a system that could have a dramatic effect on future world affairs, from American missile-tracking platforms in the Czech Republic to the ship-based defense of the Taiwan Straits.

The new radar system, called digital beamforming, could become a game-changing technology that may help defeat an overwhelming attack on U.S. warships by missiles. It could also answer one of the chief complaints about ballistic missile defense systems -- that decoys or other countermeasures could easily hide a warhead and spoof interceptors. If placed on satellites, new spy and environmental monitoring missions become possible from orbit.

All this comes as an improvement to an existing system called phased-array radar. While traditional radars spin their faces to seek targets, phased-array radars guide a reflective beam electronically from a stationary panel. They can track things by moving the main beam very quickly, within microseconds, at numerous targets. But the phased array systems cannot seamlessly track multiple targets at the same time without losing resolution. Lockheed's improvement on these radars allows true simultaneous tracking, with each target followed by a dedicated radar beam.

Digital beamforming, then, combines the cutting edges of antenna and digital technologies: A radar array digitizes the signals it receives, preserving all the incoming information. This data is then used to form as many radar beams as necessary to track as many objects as appear. The crucial advantage to this approach is the ability to confidently cover a vast area with a single system.

Lockheed for the first time has been testing a digital beam array to locate and track live targets -- in this case, commercial and military aircraft coming in and out of the Philadelphia area. "The hard part was how we combined all the data...to form the individual beams," Scott Smith, program manager for the radar system at Lockheed, tells PM. Commercially available high-speed digital electronics and advanced signal processors have become advanced enough to allow this data processing to occur, and that in turn has enabled digital beamforming to become practical for use outside a lab.

One key component to all phased-array radars is transmit/receive modules. These inch-long modules increase the power of the transmitted signal, ready the system to receive responses and steer the beam to find targets. Lockheed engineers have used new materials in digital beamforming t/r modules that make them tough enough to hold up to harsh use. By using heat-tolerant silicon carbide in the modules, more power can be pumped through them, giving the radar a longer range and a very precise targeting ability.

Digital beamforming radars will likely find their first homes on ships that track missile threats to U.S. fleets. Those threats will come from ballistic launches hundreds of miles away or from high-speed missiles launched from submarines or warplanes. The Russian government has been busy selling sea-skimming, antiship missiles to China that are designed to overwhelm the U.S. fleet's radars, so the ability to track multiple, fast-moving threats could become vital in the Taiwan Straits. But a digitized phased array radar can handle many incoming signals at once, and should be able to discern real threats from bits of metal or shaped decoy balloons. So somewhere a Chinese admiral is frowning at Lockheed's news, and a Taiwanese general is smirking.

The development could even fuel Russian paranoia over its nuclear deterrent and make its leadership more intransigent about U.S. radar bases, ostensibly established to protect Europe from Iranian missiles, on its border in Eastern Europe. One way to beat radar systems is to overwhelm them with signals, including decoys.
Therefore, beamforming can change missile defense equations in favor of the defenders. "Russian analysts examining the [missile defense] system would conclude that, at some unforeseen future time...it might be able to engage many hundreds of targets," a 2007 Arms Control Association report noted. "Such possibilities, however remote they would seem, would certainly conjure up apocalyptic threats to Russia's national survival."

Maybe not so remote: If the radar ground stations that the U.S. wants to establish in the Czech Republic are upgraded with beamforming technology, they could spot Russian missiles just after launch, follow as many missiles as could be put into the air, track inbound warheads amid intentionally scattered decoys and shoot down the real threats. The balance of power in Europe could shift as Russia loses its deterrent edge.

Read more on this and other high-tech headlines from our friends at Popular Mechanics on Military.com.

-- Christian

Protecting Spacecraft from Space-Junk

Micrometeorites and undetectable bits of space junk as small as 0.4 mm pose a serious threat to every current and future manned space mission. These dust-size particles travel as fast as 12 miles per second, packing enough momentum to melt aluminum spacecraft skin -- or turn it into a puff of vapor.

To find small holes, astronauts must use handheld ultrasonic devices such as directional microphones -- a time-consuming process. NASA scientists seeking other solutions are focusing on new wireless technologies that can find tiny leaks by tracking vibrations across a spacecraft’s metal skin.

"There is turbulence as the air spreads in the vacuum, and that reacts against the plate at the edge of the hole," says Dale Chimenti, a professor at Iowa State University who's developing the inch-long sensors for NASA.

The sensors would stud the inside of the shell of a spacecraft, giving mission controllers a faster way to locate leaks before problems arise. Multiple instruments would be needed to safeguard the entire craft and triangulate the signals to pinpoint a location.

The technology may not be funded for use in the International Space Station or shuttle fleet, but interest from future space programs is high. Earthbound applications include monitoring pipelines and pressurized oil tankers.

Read more about this story, debate over NASA's next lunar mission, the search for an 'open source rocket' and who's gonna get the 'geek vote' from our friends at Popular Mechanics on Military.com.

-- Christian

Robot Surgeons Closer Than You Think

While aboard a DC-9 aircraft, a remote operator uses a robot to suture a section of simulated tissue.

If a robot surgeon is treating you, your life is in danger. That's not due to any machine-borne malice, but because current research into autonomous surgery is focused on battlefield casualties barely clinging to life and astronauts injured on distant planets. To demonstrate how that research is progressing, Silicon Valley-based SRI International and the University of Cincinnati held a series of tests this past September that sound like a cross between a PR stunt and a B-movie: human doctors squaring off against a robotic surgeon aboard a nose-diving DC-9 aircraft.

During periods of zero gravity and sustained acceleration of 1.8 g's, a robot made incisions and applied sutures on simulated tissue, while a human surgeon did the same. The purpose: to measure just how precise a remote-operated robot can be, especially in a turbulent or gravity-free environment. SRI hasn't released its results, but according to PM Advisory Board member Dr. Ken Kamler, who participated in one of the flight tests, the robot seemed to hold its own—until its compensation software was turned off. "The difference was huge," Kamler says. "It was virtually impossible [for it] to tie a knot." But with compensation engaged, the bot performed as well as it did on Earth.

And so the tests' true purpose was to showcase SRI's software. "We're not mimicking a surgeon," says Tom Low, SRI's director of medical devices and robotics, "but looking at what a robot can do better." By focusing on adaptive algorithms, SRI wants to move away from remote telesurgery and closer to autonomy. The company plans to build a system for NASA that could treat an astronaut on Mars, where communication delays of more than 20 minutes would make telesurgery impossible...

Read more about robotic doctors and other high-tech stories from Popular Mechanics at Military.com.

-- Christian