Issue No. 05 - May (2011 vol. 44)
DOI Bookmark: http://doi.ieeecomputersociety.org/10.1109/MC.2011.146
Flying Robots Designed to Form Emergency Network
European academic researchers have developed a constellation of robust, lightweight flying robots using wireless communications that could be employed in mapping, remote sensing, ground searches, and other similar operations.
The scientists are developing technology for a Swarming Micro Air Vehicle Network, said Jean-Christophe Zufferey, group leader for flying robotics research at Ecole Polytechnic Federale de Lausanne's Laboratory of Intelligent Systems. A SMAVNET will consist of a set of robots that can fly at low altitudes, communicate wirelessly with one another, and coordinate their activities. They then form a communications network that could be used by, for example, rescuers in a remote area.
The robots consist of a flying-wing airframe, with neither fuselage nor tail. They are propelled by a single electric motor running on a battery capable of 30 minutes' life. The aircraft have an 80-centimeter wingspan, weigh about 500 grams, and are built with inexpensive, lightweight yet strong polypropylene foam. This lets them land on virtually any terrain without damage, according to Zufferey.
Their airspeeds can range between 8 and 20 meters per second (between 18 and 45 miles per hour), and they can fly as high as several kilometers, although a swarm generally stays below 150 meters to avoid conflicts with general aviation.
Severin Leven, a doctoral student working on the project, said experimental flights with swarms of drones pose a challenge because so many individual aircraft are involved. The robots must be able to fly with minimal or no external human input, but must also coordinate their activities as part of a group.
Once hand launched, Zufferey explained, a robot relies on autopilot to control airspeed, altitude, turn rate, and stabilization. The drones use actuators to control steering.
A small circuit board, running Linux and powered by an Intel XScale PXA270 processor, is programmed with algorithms to provide commands to the autopilot for controlling drones acting as part of a swarm. The robots also have a microcontroller that reads sensor data and computes outputs sent to the actuators.
Swarming algorithms enable the robots to form themselves into an effective flight group, which then functions as a communications network. The drones use the IEEE 802.11n version of Wi-Fi, implemented via dongles, for line-of-sight transmissions to one another over distances of up to 500 meters, explained Zufferey. Users could then communicate with the drones via smartphones or computers.
The drones can use GPS to fly to specified locations to, for example, return to a take-off location, safely land if the battery is drained, or gather with other drones to operate as part of a swarm.
Part of the researchers' work was inspired by the way army ants communicate, specifically their practice of laying and maintaining pheromone paths between nests and food sources. To imitate this behavior, the robots can act as either ants or nodes.
Initially, they spread out and fly as far as their communication range allows, remaining in contact with neighboring drones. At that point, they become nodes, circling fixed positions and acting as communication highways for ant drones, which use information the nodes provide to determine the best flight paths.
As ant drones fly farther from the grid, they can sometimes become nodes and expand the network, if it strengthens communications. The swarm's purpose is to establish an optimal communications network to, for example, enable first responders to stay in touch with one another in a remote area where communication has been disrupted.
So far, the researchers have built and flown 10 robots at a time. The scientists are commercializing their work via a company they formed, senseFly ( www.sensefly.com), which is currently offering small drones for autonomous-mapping and remote-sensing applications.
Mobile Malware on the Rise
Each year since cell phone use became popular, security experts have said malware that affects mobile devices was on the verge of becoming a problem. But each year, that didn't happen. Now, though, it appears that mobile malware has arrived.
Devices such as smartphones can contain valuable information like credit card numbers, usernames, and passwords. According to Vikram Thakur, principle security response manager for security vendor Symantec, such data is a valuable black-market commodity. This makes smartphones potentially desirable targets for cybercriminals.
Another factor driving mobile malware is that wireless devices are becoming more popular than traditional PCs, even for confidential purposes such as banking and other financial transactions. For example, smartphone sales exceeded PC sales for the first time in the fourth quarter of 2010, according to Luis Corrons, director of Panda Security's PandaLabs.
As occurred with PC malware, hackers eventually will figure out how to make money from information collected via mobile malware, encouraging expansion of the practice, predicted Thakur. With this in mind, he noted, hackers have increased proof-of-concept attacks on mobile devices, including spyware-installation and phishing attempts, as well as efforts to circumvent authentication.
There have also been malicious fake wireless-security products, and financially motivated social-engineering-based Trojans have been embedded in mobile games.
Noted Don DeBolt, director of threat research for CA Technologies' Internet Security Business Unit, hackers can use botnets to distribute mobile ransomware, malware that makes data on a system unavailable in an attempt to force a user to pay a ransom for its restoration.
Symantec recently discovered an attempt to create a botnet consisting of devices that run Google's Android operating system, the world's most widely used smartphone OS.
The platforms with the greatest market share are most attractive to hackers and thus face the greatest risk, said CA Technologies senior malware researcher Dinesh Venkatesan.
Recent Android-related incidents highlight mobile devices' vulnerabilities. Several programs available via Google's Android Market for applications early this year appeared to be legitimate software, but hackers had actually added Trojans to them. Google removed the altered programs from the Android Market, but not before they had been downloaded thousands of times. The company subsequently distributed software to eliminate rogue applications from users' devices.
Mobile platforms other than Android have also experienced problems. For example, Trojans have affected devices running the Symbian OS, noted Venkatesan. The SymbOS.Merogo short-message-service worm also targets Symbian, PhoneSnoop spyware affects BlackBerry devices, and the iPhoneOS.Ikee worm was designed for Apple's iOS mobile platform.
Most security vendors are using the same approaches to combat mobile malware that they've used on the PC, such as endpoint scanning, explained Venkatesan. Some infrastructure companies, such as Cisco Systems, are trying to extend security beyond the corporate network's physical perimeter by, for example, enforcing company policies at the router closest to a managed mobile device, he added.
Despite the rise of mobile malicious software, Corrons said, security researchers still see much more new PC malware.
Dual-Core Processors to Improve Smartphone Performance
An increasing number of people are now using smartphones as mobile computers, prompting an ongoing drive to improve the devices' performance.
With this in mind, several companies are now providing dual-core chips for smartphones and tablets. Adding more cores, says Nathan Brookwood, Insight 64 analyst, is the most power-efficient way to increase mobile processors' performance. Dual-core processors achieve high performance speeds because they divide up tasks and perform them in parallel—a technique known as symmetric multiprocessing.
Running multithreaded applications in parallel on dual cores can provide a performance boost. Brian Carlson, OMAP 5 product line manager for Texas Instruments' Wireless Business Unit, says his company has measured a 1.6× performance increase using dual-core processors to run Web browsers. Brookwood adds that software developers, led by game developers, have begun redesigning their software to run in parallel.
Dual-core chips also provide scalability for both power and performance, factors that are critical for smartphones' high on-demand performance requirements. They can, for example, either provide additional performance when needed or shut down one of the cores to conserve power.
Smartphones won't use the same types of dual-core processors currently found in PCs and laptops, primarily because mobile chips are significantly smaller. The TI chips, for example, are 12 mm × 12 mm, not the 37 mm × 37 mm or larger chips found in a desktop system. They also run at milliwatts rather than watts.
These devices need ARM-compatible chips to cope with their completely different operational requirements, which include an inability to cool chips and the need for low power. Vendors including Nvidia, Qualcomm, TI, and Motorola are now supplying dual-core ARM chips precisely for this market. The LG Optimus 2X runs Nvidia's dual-core Tegra 2 processor, and TI's OMAP 4 dual-core processors can be found in the LG Optimus 3D as well as in tablets, including the RIM PlayBook. Motorola is using dual-core chips in its ATRIX 4G phone and XOOM tablet. According to Brookwood, Intel anticipates that its Medfield Atom processor, scheduled to ship later this year, will make inroads into the smartphone and tablet markets.
ARM has traditionally emphasized performance per watt at the low-power levels needed for long battery life, Brookwood says, which has allowed the technology to lead in this market segment. Unlike Intel and AMD, ARM licenses its designs to third-party system-on-chip designers, who then combine ARM's intellectual property with other system elements to create custom-tailored SoCs with the size, power, and performance characteristics that smartphone designs require.
Carlson says the prime issue with using dual-core processors in smartphones is achieving a performance-power balance. These constraints are already familiar to chipmakers and phone designers.
The market opportunities are huge, analysts say. According to a March 2011 report by ABI Research, mobile data plan revenues alone are expected to exceed $102 billion worldwide by 2016, fueled by mobile enterprise customers' smartphone adoption. Brookwood says that while analysts may differ about how smartphone adoption will affect the computer market, they do agree there will be a change.
News Briefs written by Linda Dailey Paulson, a freelance technology writer based in Portland, Oregon. Contact her at firstname.lastname@example.org.