Developing Space 'Tow Truck' Technology For Satellite Operations

The Naval Research Laboratory's Naval Center for Space Technology has achieved a key milestone toward the development of autonomous servicing of unaided spacecraft.

Working with the Defense Advanced Research Projects Agency (DARPA), NRL has developed, tested and ground-demonstrated guidance and control algorithms to allow a robotic servicing vehicle to autonomously rendezvous and dock with customer satellites not pre-designed for docking.

This demonstration coupled three significant accomplishments into one milestone, program managers say. The necessary robotic control algorithms are proven to be capable of operating reliably within a realistic spaceflight-processing environment and are now flight traceable.

A simulation of a realistic geostationary communications satellite with no visual aids or docking aids was grappled reliably in realistic on-orbit lighting conditions.

The demonstration was completed under full autonomy with no human-in-the-loop assistance.
NRL and DARPA are developing the key technologies and reducing the technological risk to allow autonomous spacecraft rendezvous and docking to become a reliable reality. As part of the Front-end Robotics Enabling Near-term Demonstration (FREND) effort, the DARPA/NRL team is advancing the state-of-the-art in spacecraft autonomous rendezvous and grappling, offering "tow-truck" service to nearly every satellite currently, or soon to be, in space. This service offers potential for satellites to operate longer, to be salvaged if they are in an inoperable orbit, to be transferred to a new orbital position if they are unable to make that transit on their own, and has a capability for making certain orbital regimes safer by transferring derelict spacecraft or space debris into graveyard orbits.

Full-scale laboratory demonstrations have now been successfully completed, proving that reliable autonomous grapple of spacecraft hardware is feasible. The NRL team has accomplished autonomous grapples using a one-meter-long research grade robot arm, custom developed flight traceable control algorithms, research grade machine vision cameras, prototype grappling mechanisms, and flight traceable processors. These grapples have been of simulated spacecraft hardware, grappling at the launch vehicle interfaces (Marman ring, separation bolt hole) commonly flown to geosynchronous orbit, and with simulated in-space lighting conditions.

By accomplishing these technology demonstrations, the autonomous control algorithms advance from a spaceflight Technology Readiness Level (TRL) of 4 to a TRL of 5, by having been tested in a variety of relevant environments. The DARPA/NRL team will further improve the TRL by integrating flight-ready robotics, electronics and software with evolving algorithms for grapple demonstrations in the laboratory environment. Laboratory demonstrations with fully flight-ready components will be another major milestone toward the ultimate goal of reaching the highest TRL of 9, which is reserved for systems that have been proven through successful operations in space.

DARPA and NRL have contracted the expertise of Alliance Spacesystems, LLC of Pasadena, CA, to design and build the robotics that would allow a servicing spacecraft to dock with satellites not originally designed for servicing. Alliance is best known for designing and building the robot arms that are successfully exploring Mars on both Mars Exploration Rovers, Spirit and Opportunity. Alliance is presently designing, fabricating and testing of the first two robot arms for the FREND program. An engineering development unit (EDU) robotic arm was scheduled for delivery to NRL in August, with a second flight prototype unit (FPU) built to space flight requirements being delivered in July 2008. Both arms will be built to meet the performance and test requirements set forth by NRL, which emphasize operability in both Earth's gravity for laboratory testing and the zero-gravity environment of space.

Once the FREND technology prototype is fully demonstrated over the next year, it will have reached a spaceflight TRL of 6 and will be ready for an on-orbit demonstration mission. DARPA is presently involved in a search to identify a spacecraft mission partner for the on-orbit demonstration phase of this technology. Any interested government; private or other entities should contact the DARPA Tactical Technology Office. Parties interested in the FREND spacecraft technology should contact NRL's Naval Center for Space Technology.

Watch more breaking news now on our video feed:

Bookmark http://universeeverything.blogspot.com/ and drop back in sometime.

Sandia Researchers Help To Make Cars Smarter

Cars already automatically lock doors when they sense motion and turn on warning lights if they detect potential engine problems.

But they are about to get smarter.

The augmented cognition research team at Sandia National Laboratories is designing cars capable of analyzing human behavior.

The car of the future they are developing may, for example, deduce from your driving that you’re become tired, or during critical situations, tell your cell phone to hold an incoming call so you won’t be distracted.

The project started about five years ago with funding by the Defense Advanced Research Projects Agency (DARPA). Four years ago Sandia partnered with a major commercial automobile manufacturer, and three years ago did actual experiments on European roadways.

“We utilized data that already existed on the car’s computer to collect a wide range of physical data such as brake pedal force, acceleration, steering wheel angle, and turn signaling,” says Kevin Dixon, principal investigator. “And specialized sensors including a pressure sensitive chair and an ultrasonic six-degree-of freedom head tracking system measured driver posture.”

Five drivers were fitted with caps connected to electroencephalogram (EEG) (brainwave) electrodes to gauge electrical activity of the brain as they performed driving functions.

The researchers collected several hours of data in unstructured driving conditions that were imputed into Sandia software, referred to as “classifiers,” that categorized driving behavior. These classifiers could detect certain driving situations such as approaching a slow-moving vehicle or changing lanes in preparation to pass another vehicle.

The system detects the difficulty and stress of the task the driver is attempting. It then tries to modify the tasks and/or environment to lower the stress and improved specified performance parameters.

Similar experiments were conducted for off-road driving where conditions were much less structured than typical roadways.

“The beauty of this is that we aren’t doing anything new or different to the car,” Dixon says. “All the software that can make the determination of ‘dangerous’ or ‘safe’ driving situations would all be placed in the computer that already exists in the car. It’s almost like there is another human in the car.”

Watch more breaking news now on our video feed:

Bookmark http://universeeverything.blogspot.com/ and drop back in sometime.

Pentagon Challenge Aimed At Self-Driving Cars

The Pentagon's research arm, the Defense Advanced Research Projects Agency (DARPA), is working to develop vehicles that drive themselves autonomously. Watch this report to see what engineers are working on to make this a reality today.

The Urban Challenge will be held in November. To learn more about the race and the technology, log on to: www.tartanracing.org

Bookmark http://universeeverything.blogspot.com/ and drop back in sometime.

Prosthetics 2009 Team Delivers 1st Advanced Limb Prototype

An international team led by the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Md., has developed a prototype of the first fully integrated prosthetic arm that can be controlled naturally, provide sensory feedback and allows for eight degrees of freedom—a level of control far beyond the current state of the art for prosthetic limbs, researchers say.

Proto 1, developed for the US Defense Advanced Research Projects Agency (DARPA) Revolutionizing Prosthetics Program, is a complete limb system that also includes a virtual environment used for patient training, clinical configuration, and to record limb movements and control signals during clinical investigations.

The DARPA prosthetics program is an ambitious effort to provide the most advanced medical and rehabilitative technologies for military personnel injured in the line of duty. Over the last year, the APL-led Revolutionizing Prosthetics 2009 (RP 2009) team has worked to develop a prosthetic arm that will restore significant function and sensory perception of the natural limb. Proto 1 and its virtual environment system were delivered to DARPA ahead of schedule, and Proto 1 was fitted for clinical evaluations conducted by team partners at the Rehabilitation Institute of Chicago (RIC) in January and February.

“This progress represents the first major step in a very challenging program that spans four years and involves more than 30 partners, including government agencies, universities, and private firms from the United States, Europe, and Canada,” says APL’s Stuart Harshbarger, who leads the program. “The development of this first prototype within the first year of this program is a remarkable accomplishment by a highly talented and motivated team and serves as validation that we will be able to implement DARPA’s vision to provide, by 2009, a mechanical arm that closely mimics the properties and sensory perception of a biological limb.”

Bookmark http://universeeverything.blogspot.com/ and drop back in sometime.