Special Coverage

Transducer-Actuator Systems for On-Machine Measurements and Automatic Part Alignment
Wide-Area Surveillance Using HD LWIR Uncooled Sensors
Heavy Lift Wing in Ground (WIG) Cargo Flying Boat
Technique Provides Security for Multi-Robot Systems
Bringing New Vision to Laser Material Processing Systems
NASA Tests Lasers’ Ability to Transmit Data from Space
Converting from Hydraulic Cylinders to Electric Actuators
Automating Optimization and Design Tasks Across Disciplines
Vibration Tables Shake Up Aerospace and Car Testing
Supercomputer Cooling System Uses Refrigerant to Replace Water

Alkyl Pyrocarbonate Electrolyte Additives for Li-Ion Cells

Beneficial properties of films that form on carbon anodes are enhanced.

Alkyl pyrocarbonates have been found to be useful as electrolyte additives for improving the low-temperature performances of rechargeable lithium-ion electrochemical cells. The beneficial effects of these and other additives have been investigated, along with various electrolyte formulations, in continuing research directed toward extending the range of practical operating temperatures from the present lower limit of –20 °C down to –40 °C, and even lower if possible. This research at earlier stages was reported in a number of NASA Tech Briefs articles; namely, “Update on Electrolytes for Low-Temperature Lithium Cells” (NPO-20407), Vol. 24, No. 1, (January 2000), page 56; “Lithium Alkoxide Electrolyte Additives for Lithium-Ion Cells” (NPO-20607), Vol. 25, No. 6 (June 2001), page 52; “Aliphatic Ester Electrolyte Additives for Lithium-Ion Cells” (NPO-20601), Vol. 25, No. 6 (June 2001), page 53; and “Ethyl Methyl Carbonate as a Cosolvent for Lithium-Ion Cells” (NPO-20605), Vol. 25, No. 6 (June 2001), page 53.

Posted in: Briefs, TSP, Materials, Lithium-ion batteries, Lithium-ion batteries
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Fluorinated Alkyl Carbonates as Cosolvents in Li-Ion Cells

These solvents offer advantages with respect to performance and safety.

Partially fluorinated alkyl carbonate liquid compounds have been found to be excellent electrolyte cosolvents for rechargeable lithium-ion electrochemical cells. The benefits afforded by these and other ingredients of electrolyte solutions in rechargeable Li-ion cells have been investigated in continuing research directed toward extending the range of practical operating temperatures of the cells (from +40 °C down to –40 °C, and possibly even as low as –60 °C). Fluorinated solvents were perceived to be especially attractive in that they will result in inherently safer cells, due to their low flammability. This research at earlier stages was reported in a number of previous NASA Tech Briefs articles; namely, “Update on Electrolytes for Low-Temperature Lithium Cells” (NPO-20407), Vol. 24, No. 1, (January 2000), page 56; “Lithium Alkoxide Electrolyte Additives for Lithium-Ion Cells” (NPO- 20607), Vol. 25, No. 6 (June, 2001), page 52; “Aliphatic Ester Electrolyte Additives for Lithium-Ion Cells” (NPO-20601), Vol. 25, No. 6 (June, 2001), page 53; “Ethyl Methyl Carbonate as a Cosolvent for Lithium-Ion Cells” (NPO-20605), Vol. 25, No. 6 (June, 2001), page 53; and “Alkyl Pyrocarbonate Electrolyte Additives for Li-Ion Cells” (NPO-20775), which precedes this article.

Posted in: Briefs, TSP, Materials, Lithium-ion batteries, Lithium-ion batteries, Chemicals
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Diaminobenzoquinones as Corrosion-Inhibiting Additives

Protection can extend beyond edges of paints to adjacent unpainted areas.

Non-polymeric N,N´-di-N-hydrocarbyl- 2,5-diamino-1,4-benzoquinones (where the hydrocarbyl substituents are alkyl or aryl) have been found to be useful as corrosion-inhibiting additives for paints and other conventional coating materials that are applied to steel and other metals. Prior coating additives made from reactions of benzoquinones with diamines are polymeric. Such polymers are expensive and difficult to make. Moreover, being polymers, they cannot diffuse much and hence are believed not to protect uncoated areas of metal against corrosion. In contrast, when used in proper concentrations, the present non-polymeric diaminobenzoquinones provide enhanced protection that extends somewhat from the edges of coats into uncoated areas — an important advantage in situations in which there are imperfections (e.g., gaps, scratches, and blisters) in coats of paint.

Posted in: Briefs, TSP, Materials, Coatings Colorants and Finishes, Coatings, colorants, and finishes, Corrosion, Polymers
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Multiple-Cavity Masers as 32-GHz LNAs

Advanced designs feature compactness and high performance.

Improved multiple-cavity ruby masers are under development for use as lownoise amplifiers (LNAs) for receiving very weak radio signals in frequency bands up to and including one centered approximately at 32 GHz. These masers were designed specifically to be incorporated into receivers in ground stations of NASA’s Deep Space Network. The design may be useful in terrestrial cellular telephone terminals where high selectivity and immunity to the generation of intermodulation products may be needed.

Posted in: Briefs, TSP, Electronics & Computers, Amplifiers, Radio equipment, Amplifiers, Radio equipment
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Program for Tracking Air-Purification Cartridges

The Cartridge Automated Reliance Tracking (CART) computer program enables authorized requesters associated with NASA to gain access to the most recent tracking data on LiOH-based airpurification cartridges used during space-shuttle flights. CART could also be adapted to suit the needs of other organizations in disseminating tracking data to geographically dispersed users. The information provided by CART includes the location and flight status of each cartridge, every step in the processing of the cartridge, and the statuses of all chemicals consumed in the processing. Prior to the development of CART, reports on the statuses of cartridges were prepared manually in Kennedy Space Center’s LiOH laboratory on request and transmitted by facsimile — a slow, labor-intensive procedure. CART utilizes Oracle Forms and Tarantella Web software. Cartridge-tracking data are now stored on a central server computer and made available in a series of reports that are accessible to authorized requesters in real time via the World Wide Web.

Posted in: Briefs, Software, Computer software / hardware, Computer software and hardware, Computer software / hardware, Computer software and hardware, Air cleaners
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Software for Implementing Fuzzy Logic on Microcontrollers

Fuzzy Inference System Translator (FIST) is a computer program that facilitates the implementation of fuzzy-logic software on commercial or other viable microcontrollers. In the original application for which FIST was developed, there was a need to implement plantgrowth- chamber (PGC) temperatureand- humidity controllers that had been developed within the MATLAB Fuzzy Logic Toolbox software system. In this application, fuzzy membership functions were specified for the temperature and relative-humidity signals, and a set of weighted inference rules was developed from experience and working knowledge of an environmental chamber, containing the PGC, in which the temperature and humidity were to be controlled. First-order models of PGC dynamics, based on the temperature dependences of heat-transfer rates and water-vapor pressure, were used with SIMULINK (mathematical-modeling software compatible with the MATLAB software) for rapid prototyping of a fuzzy inference system. All the information relevant to the controller thus developed are contained in a MATLAB fuzzy-inference-system file. The role of FIST in the development of the present controller or a similar controller is to extract the relevant information from this file and process it into machine code that is executable on a specified microcontroller.

Posted in: Briefs, TSP, Software, Fuzzy logic, Computer software / hardware, Computer software and hardware, Computer software / hardware, Computer software and hardware
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Software for Constructing a Facility-Management Database

Facility Management Tracking System (FMTS) is a computer program for constructing an integrated database that defines any event in a managed facility. FMTS provides a simple user interface for entering all relevant data connected to the event. The entered data, as displayed and processed by FMTS, are used by the facility manager to determine the status of the event, control processing steps and to verify other information about the event, approve the control points of the event, and ultimately close out the event. This process assures the requirements for the facility manager’s authority over, and accountability for, meeting health and safety in the facility with a certifiable audit trail. The data can then be exported by electronic mail to other database systems maintained by organizations that are responsible for various systems within the facility. FMTS can be executed on standard personal computers and is compatible with commercial off-the-shelf server/client computer systems. The FMTS is designed to integrate modified versions of FMTS into database programs used by a variety of government and commercial organizations that have complex facility-management responsibilities.

Posted in: Briefs, TSP, Software, Computer software / hardware, Computer software and hardware, Computer software / hardware, Computer software and hardware, Data management
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Software Implements Telemetry Protocols

The CCSDS Telemetry and Telecom Software Library provides a reference implementation of the Consultative Committee for Space Data Systems (CCSDS) international protocol standard for the transmission and reception of telemetry and telecommand data in radio communications with spacecraft. The library supports the full set of uplink and downlink virtual channels. It includes a frame-acceptance and -reporting mechanism (FARM) that supports a sliding window specified in the CCSDS standard, with routines for specifying the window width. The FARM generates CCSDS-standard command link control words (CLCWs) that indicate the state of the FARM. Routines for incorporating the CLCWs into downlink telemetry streams are included. Test drivers for showing how the library functions within the context of an application program are also included. The library has been written in the C programming language for execution on various computers running the SunOS4, SunOS5, AIX, and VxWorks operating systems. Makefiles that can be tailored for other computers and operating systems are included. Both source code and documentation are provided on the distribution medium, which is a tar file.

Posted in: Briefs, TSP, Software, Computer software / hardware, Computer software and hardware, Telemetry, Computer software / hardware, Computer software and hardware, Telemetry
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Software for Parallel Processing of Telemetry

Parallel Telemetry Processor (PTEP) is a high-speed, robust, extensible, Javalanguage computer program that (1) enables the parallel processing of a serial stream of telemetric data and (2) generates a graphical display for monitoring the processing. Originally intended for application to spacecraft telemetry, PTEP could also be applied to the processing of data from other complex, heterogeneous systems that generate serial data streams. PTEP provides for multithreaded dispatching of tasks and accommodates the integration of other data-processing application programs into the processing pipeline. The PTEP graphical display is a color-coded flow chart with arrows that indicate the progress of each packet through processing steps. Also represented on the flow chart are intermediate data products and processing steps in which errors occur. Packets that cause processing errors are stored in an error queue for later review while the system continues to process new packets. At any time, a user can obtain detailed information about a processing error, correct the error, and resume processing of the affected packet.

Posted in: Briefs, TSP, Software, Computer software / hardware, Computer software and hardware, Telemetry, Computer software / hardware, Computer software and hardware, Telemetry
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Software for Global Forecasting of Winds and Waves

The WorldWinds™ software system generates high-resolution global weather forecasts, with emphasis on wind and ocean-wave vectors, in nearly real time. WorldWinds™ was developed primarily to serve organizations and individuals needing accurate forecasts for scientific, safety, or economic reasons. WorldWinds™ accepts input data from multiple satellite sources: the TOPEX altimeter, the ERS-2 scatterometer, the QuikScat scatterometer, and the SSM/I microwave radiometer. The software takes those parts of the data that pertain to wind, wave, and other weather observations, combines them with observational data from National Weather Service, and feeds them into two numerical models of weather: the Penn State MM5 model and the Harris Quasi-Lagrangian model. These models generate superior forecasts of wind and wave vectors and other weather variables for periods from 12 to 72 hours. World- Winds™ is unique in that it can forecast winds over the entire surface of the Earth, producing a seamless global weather map every hour of every day. Data can be given at spatial grid intervals that range from 120 to as little as 3 km. Both spatial and temporal scales can be adjusted to satisfy the needs of clients.

Posted in: Briefs, Software, Computer software / hardware, Computer software and hardware, Computer software / hardware, Computer software and hardware, Weather and climate
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