Tech Briefs

Polarization-Dependent Whispering Gallery Modes (WGMs) in Microspheres

WGMs can benefit sensors used in aerospace vehicle control, health and performance monitoring, optical communications, and biological applications.

Dielectric microspheres are optical structures that exhibit resonant properties, meaning they can be used to select very narrow wavelengths of an incoming light beam's spectrum for further manipulation and processing. The optical resonances of a microsphere are frequently called morphology dependent resonances (MDRs) or whispering gallery modes (WGMs). Innovators at NASA's Glenn Research Center have developed a method of separating low-level modes propagating in an optical fiber through the use of WGMs in spherical resonators. The unusually high quality factors (Q-factors) that can be achieved by side coupling of light into the dielectric spheres allow for measurement sensitivities that may far exceed those of more conventional sensors. Whispering gallery modes’ high sensitivity to environmental conditions and their small size make them good candidates for a wide range of sensors.

Posted in: Briefs, Communications, Antennas, Fiber optics, Sensors and actuators

Magnetically Conformed, Variable-Area Discharge Chamber for Hall Thruster, and Method

NASA's Jet Propulsion Laboratory has developed a Hall thruster with a variable-area discharge chamber that improves the performance and lifetime of the thruster. Conventional Hall thrusters have poor ionization efficiency, which limits the thrust-to-power ratio that can be achieved with the thruster. JPL's novel Hall thruster has a variable-area discharge chamber that conforms to the curvature of the local magnetic field and optimizes the ionization efficiency of the thruster and, therefore, significantly improves the power-to-thrust ratio that can be achieved. This innovative device decreases spacecraft costs and enables fast, efficient orbit transfers.

Posted in: Briefs, Propulsion, Engine efficiency, Spacecraft

Methods for Purifying Enzymes for Mycoremediation

This process applies to remediation and restoration of soils contaminated by fuel, polychlorinated biphenyl wastes, etc. While there can be a general beneficial effect of microbial communities, individual plant-fungus combinations can vary in their efficacy in removal of pollutants from the environment. Selection of the most effective combination of plants and fungi is very important for achieving the desired benefits. Not all fungi are created equal, as some die off in contaminated soils. Having a set of enzymes from fungi specifically adapted to conditions in contaminated soils and use of native plant/fungal combinations is a huge advantage. Ectomycorrhizal (EM) mediated remediation of phenolic-based contamination through use of specifically adapted soil and enzymes utilizes plant/fungal combinations that are specifically adapted to conditions created by phenolic application to soils, and the abilities of EM fungi to oxidize these compounds. This platform can be adapted to other ecosystems through field assessments of the EM community in each new site.

Posted in: Briefs, Green Design & Manufacturing, Land pollution, Sustainable development, Bacteria

Land Cover Viewer

The Land Use Land Cover Viewer is an online visualization tool that enables users to view land use land cover maps. The maps were developed under the Land Cover Mapping for Green House Gas (GHG) Inventories project, which sought to enable SERVIR Eastern and Southern Africa countries to have data to report on GHG inventories as required by UNFCCC. The countries for which land cover maps are available are Malawi, Rwanda, Zambia, Namibia, Botswana, Tanzania, Ethiopia, Uganda, and Lesotho. The viewer has maps for all nine countries for different epochs. Each country for each epoch has four to six maps based on two different classifications: country-specific and EPA. In addition to the viewer having the basic online map elements (legend, zoom, etc.), it has statistics modules that display the basic statistics of the displayed map based on a selection by the user.

Posted in: Briefs, Green Design & Manufacturing, Cartography, Imaging and visualization, Greenhouse gas emissions, Weather and climate

Low-Cost RFID Torque and Tension Sensing Tag System

The system has applications in shipbuilding, aerospace engine construction, and other high-tech equipment.

This technology is a low-cost RFID-based torque and tension sensor for high-performance fasteners, such as bolts, that are used in sophisticated high-tech equipment and systems. It offers the ability to remotely and quickly verify that a given fastener is torqued properly, resulting in potential cost-savings over the life of the fastener and its host system. The technology is also extremely low-cost compared to current torque sensing wrenches and comparable technologies. This asset management tool offers performance and safety improvements as well. The motivation behind this invention was the catastrophic event in which a NOAA satellite sustained heavy damage after falling from a Turn-Over-Cart (TOC). The root cause was a configuration change in which 24 bolts had not been secured properly to the TOC. With this NASA invention, the quality assurance, tension monitoring, and configuration management associated with proper torqueing of fasteners will be largely automated, therefore providing a higher degree of safety.

Posted in: Briefs, Sensors, Remote sensing, Radio-frequency identification, Fasteners

SpinDx™ Lab on a Disk

Currently, when a patient arrives at the hospital or doctor's office feeling ill, they are first examined by the doctor, sent to a blood lab where vials of blood are taken, and then sent home to wait for results. This approach often means patients must wait days or weeks to get results. During that waiting period, they are not receiving treatment, which can be a critical factor for cancer, heart attack, or stroke patients.

Posted in: Briefs, Sensors, Computer software and hardware, Diagnosis, Medical equipment and supplies, Test equipment and instrumentation

Cellular Reflectarray Antenna and Method of Making Same

A simple-to-install design for satellite and communications applications solves the problems associated with traditional parabolic reflectors.

NASA's Glenn Research Center invites companies to license a new concept design for terrestrial satellite dishes and communications systems. The Cellular Reflectarray Antenna (CRA) has been developed and tested for use with next-generation Ka-band satellites, although it can be used with all bands of satellite communication. The design's flat, planar configuration all but eliminates the wind-loading problems associated with larger parabolic reflectors for dish systems. The technology also offers unique features that provide ease of installation and improved signal reception, while deterring piracy and theft of subscription satellite services.

Posted in: Briefs, Communications, Antennas, Cyber security, Wireless communication systems, Satellites

Low-Power, Special-Purpose Chip for Speech Recognition in Electronics

Automatic speech recognition is on the verge of becoming the chief means of interacting with computing devices. To address this, MIT researchers have built a low-power chip specialized for automatic speech recognition. Whereas a cellphone running speech recognition software might require about 1 Watt of power, the new chip requires between 0.2 and 10 milliwatts, depending on the number of words it has to recognize. That probably translates to a power savings of 90 to 99 percent, which could make voice control practical for relatively simple electronic devices, including power-constrained devices that harvest energy from their environments, or go months between battery charges.

Posted in: Briefs, Sensors, Integrated circuits, Human machine interface (HMI), Sound quality

9-Meter Slaving System

The objective of the 9-Meter Slaving System is to transmit Launch Trajectory Acquisition System (LTAS) data from one of multiple incoming data streams to the 9-Meter antenna control unit using a synchronous serial modem. The data stream is determined by a 9-Meter telemetry operator's selection via a graphical user interface (GUI).

Posted in: Briefs, Communications, Trajectory control, Antennas, Telemetry, Entry, descent, and landing

The software package is a front end to an existing free software package written by Lawrence Livermore National Lab, called “Climate Model Output Rewriter” (CMOR2), and reads in a multitude of standard data formats such as netcdf3, netcdf4, Grads control files, MATLAB data files, or a list of netCDF files. The software prepares Earth Science Observational (obs4MIPs) data or Climate Modeling Reanalysis (ana4MIPs) data for publication in the NASA Center for Climate Simulation (NCCS) Earth System Grid Federation system (ESGF). It converts the data into a netCDF file following the Climate and Forecast (CF) metadata convention as specified by Climate Model Intercomparison Project (CMIP5). addresses the differences in input data format, variable definition, and Global Attribute requirements that exist within observational and re-analyses datasets.

Posted in: Briefs, Green Design & Manufacturing, CAD, CAM, and CAE, Weather and climate, Data management

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