DARPA floats aerial surveillance Dragnet by UAV

As off-the-shelf unmanned autonomous systems (UAS) become less expensive, easier to fly, and more adaptable for terrorist or military purposes, U.S. forces will increasingly be challenged by the need to quickly detect and identify such craft, especially in urban areas, where sight lines are limited and many objects may be moving at similar speeds.

To map small UAS in urban terrain, the U.S. Defense Advanced Research Projects Agency (DARPA) seeks innovative technologies to provide persistent, wide-area surveillance of all UAS operating below 1,000 feet in a large city. While the newAerial Dragnet program focuses on protecting military troops operating in urban settings overseas, the system could ultimately find civilian application to help protect U.S. metropolitan areas from UAS-enabled terrorist threats.

“Commercial websites currently exist that display in real time the tracks of relatively high and fast aircraft—from small general aviation planes to large airliners—all overlaid on geographical maps as they fly around the country and the world,” said Jeff Krolik, DARPA program manager. “We want a similar capability for identifying and tracking slower, low-flying unmanned aerial systems, particularly in urban environments.”

Although several systems are being developed for tracking small UAS by extending surveillance methods used in open areas where large line-of-sight buffers mitigate the threat, these systems are impractical for operation in urban terrain. Aerial Dragnet seeks to leapfrog these approaches by developing systems adapted to the fundamental physics of small UAS in urban environments that could enable non-line-of-sight (NLOS) tracking and identification of a wide range of slow, low-flying threats.

The program envisions a network of surveillance nodes, each providing coverage of a neighborhood-sized urban area, perhaps mounted on tethered or long-endurance UAS. Using sensor technologies that can look over and between buildings, the surveillance nodes would maintain UAS tracks even when the craft disappear from sight around corners or behind objects.

Low Cost Sensors, SDR. The output of the Aerial Dragnet would be a continually updated common operational picture of the airspace at altitudes below where current aircraft surveillance systems can monitor, disseminated electronically to authorized users via secure data links. Because of the large market for inexpensive small UAS, the program will focus on combining low-cost sensor hardware with software-defined signal processing hosted on existing UAS platforms. The resulting surveillance systems would thus be cost-effectively scalable for larger coverage areas and rapidly upgradeable as new, more capable and economical versions of component technologies become available.

The Aerial Dragnet program seeks teams with expertise in sensors, signal processing, and networked autonomy to achieve its goal. A solicitation detailing the goals and technical details of the program was posted here. A Proposers Day took place in late September.

Inertial, Gyroscope Take to Space

The concept image above shows the NEA Scout CubeSat with its solar sail deployed as it characterizes a near-Earth asteroid. (NASA)

Sensonor AS of Norway has partnered with the U.S. National Aeronautics and Space Administration (NASA) to supply current and future low- and near-Earth orbit space missions with inertial and gyroscope modules.

The Norway-based company first began supplying its standard inertial measurement unit (IMU) and gyroscope modules for low Earth orbit (LEO) space applications in 2012, Sensonor’s STIM300 and STIM210 inertial products now fly aboard several NASA spacecraft. Current projects using STIM inertial systems include the Raven technology demonstration and Near Earth Asteroid (NEA) Scout.

Raven, which launched to the International Space Station in September, will test key elements of an autonomous relative navigation system. Its technologies may one day help future robotic spacecraft autonomously and seamlessly rendezvous with other objects in motion, such as a satellite in need of fuel or a tumbling asteroid.

The NEA Scout is a robotic reconnaissance mission that will be deployed to fly by and return data from an asteroid representative of NEAs.

The STIM gyroscope modules are often used in combination with GPS or a Star Tracker and Kalman filter to orient and stabilize the satellite, as well as to provide feedback on satellite motion induced by its reaction wheels. In some applications, the gyroscopes are used to stabilize satellite-to-satellite communications.

Lighting Up Indoors for Retail Position

A new indoor positioning system uses LED lighting to pinpoint location for use in the retail industry. Researchers from the University of South Australia have developed an indoor positioning system that tracks movement with greater accuracy than contemporary RFID and Wi-Fi based systems.

Developer Siu Wai Ho said other methods of indoor positioning such as Wi-Fi were only accurate to within 1–2 metres and were easily hampered by radio frequencies from nearby devices, power sources or other wireless electronics. “Our system is more accurate with an error margin of 10cm and unlike some positioning systems our algorithm can calculate the orientation at the same time.”

LiPo uses LED lights as transmitters and photodetectors as receivers because they are both common items in modern societies. Photodetectors are a key component for capturing light and are also commonly found in smart phone cameras. The system uses a specially designed receiver to measure light intensity that is able to calculate position and orientation. Although it currently requires a unique receiver, developers hope to integrate the technology with the photodectors in mobile phones. This would reportedly enable supermarkets to provide customers with relevant information about items nearby.

“If you are in a supermarket you want to see some information for a product in front of you. One or two metres of error is still too big because it maybe gives you a product you are not in front of.”
Other applications could include the identification of objects or machinery in factories, movement aid tools for the elderly and trackers for museums to provide relevant information to tourists as they passed by exhibits.

Munich SatNav Summit Stresses GNSS Back-Up

“Is it Time for GNSS Back-Up?” has been announced as the the theme of the 2017 Munich Satellite Navigation Summit, to take place March 14–16.International experts gather to discuss recent position, navigation and timing develeopment and the necessity for GNSS backup solutions.

Among the topics, in addition to system updates on all major GNSS, we find listed: From Iridium to e-Loran — GNSS in need for a Backup; Galileo after the Brexit; Civil use of the Galileo Public Regulated Service (PRS); and Network-based solutions for GNSS Backup. Go to to www.munich-satellite-navigation-summit.org for registration information.

Xsens Offers Knowledge BASEd Inertial Motion Tracking

Xsens has launched BASE, an online technology platform with a community forum and a knowledge base on 3D motion tracking technology and products. BASE.xsens.com, contains inside information about micro-electro-mechanical system (MEMS) sensors, inertial measurement units (IMU), sensor fusion algorithms, body-motion tracking and motion capture.

It also provides best practices, tips and tricks for the use of Xsens’ MTi series, the MTw and the MVN wearable motion capture solutions. A second section of BASE is the community forum with direct access to Xsens’ engineers and other Xsens users.

There is no need to register for BASE to access the community forum and the knowledge base. To ask questions or comment on articles, registration is possible via SSO or email.