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Wide Temperature Range DC-DC Boost Converters for Command/Control/Drive Electronics Project
nasa-test-0.demo.socrata.com | Last Updated 2015-07-20T05:23:03.000ZWe shall develop wide temperature range DC-DC boost converters that can be fabricated using commercial CMOS foundries. The boost converters will increase the low voltage supply (~ 0.7 to 3V) of an advanced CMOS integrated circuit to the higher values (3-10V) required for integrated command/control/drive electronics for sensors, actuators and instrumentation. The high voltage capability is a result of our patented, CMOS compatible transistor technology that is radiation tolerant (TID>1 MRad), SEL immune and capable of wide temperature range operation (-196C to +150C). This new transistor technology has been demonstrated at multiple foundries and advanced device models are available for circuit design and simulation. The DC-DC boost converters will be integrated directly with the CMOS components to provide a single chip solution, greatly reducing the number of active and passive components that would otherwise be required. By allowing enhanced voltage operation in future CMOS technology nodes we will be avoiding many of the obsolescence problems facing NASA missions that are dependent upon commercial electronics. The circuits will be designed to operate in low temperature environments that experience wide temperature swings such as those found on the moon, Mars, Titan, Europa and comets.
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Electronics Modeling and Design for Cryogenic and Radiation Hard Applications Project
nasa-test-0.demo.socrata.com | Last Updated 2015-07-20T05:16:28.000ZWe are developing CAD tools, models and methodologies for electronics design for circuit operation in extreme environments with a focus on very low temperature and radiation effects. These new tools will help enable NASA to design next generation electronics especially for planetary projects including the Europa Jupiter System Mission. The new models and tools will be directly incorporated into industry standard CAD products to ensure their usability and extend their applicability to extreme environments. Such capabilities will significantly improve reliability, performance and lifetime of electronics that are used for space missions. This will be achieved through the development of novel compact and distributed device modeling capabilities for radiation-hard and extreme temperature instrument design, as well as techniques for circuit design that help to predict the vulnerability of circuits to degradation and upset from radiation. Research and development is indicating that standard bulk silicon CMOS and SOI processes operate well under these extreme conditions so that there is little need for NASA to commit to large expenditures for exotic materials. Models and CAD tools are relatively inexpensive as compared to fabrication costs; thus the results of this project should provide a very large return on investment.
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Planning for Planetary Science Mission Including Resource Prospecting Project
nasa-test-0.demo.socrata.com | Last Updated 2015-07-20T05:33:43.000ZAdvances in computer-aided mission planning can enhance mission operations and science return for surface missions to Mars, the Moon, and beyond. While the innovations envisioned by this program are broadly applicable, they serve an immediate and urgent need for missions to prospect for volatiles at the lunar poles (i.e., the NASA Lunar Resource Prospector Mission, currently in Phase A). These missions must be rapid and precise, covering multiple kilometers in approximately 10-12 Earth days to complete mission objectives in one lunar light cycle. This calls for the ability to drive intentionally and efficiently to precise drilling destinations. Polar operations encounter low angle lighting; this creates shadows which confront robot operations with challenges in power production, thermal control, and operator situational awareness. This demands robust path planning for efficient mission planning and execution. The proposed work develops a computer-aided mission planning tool that balances the competing demands of efficient routes, scientific information gain, and rover constraints (e.g., kinematics, communication, power, thermal, and terrainability) to generate and analyze optimized routes between sequences of locations. Planner-computed statistics about the set of viable paths enable mission planners, scientists, and operators to efficiently select routes considering a range of priorities including risk, duration, and science return. This planner will serve an invaluable role in preplanning missions and as a tool for rapidly understanding the impact of changes in mission profile during the mission execution.
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Including the effects of a harsh radiation environment in the simulation and design of nanoelectronic devices and circuits Project
nasa-test-0.demo.socrata.com | Last Updated 2015-07-20T05:31:59.000ZNanoelectronic devices, and circuits based on such devices, are expected to be more susceptible to the effects of radiation than the previous generation of devices and circuits. Circuits that can operate in harsh radiation environments are essential components of commercial satellite communications systems, space exploration vehicles, and national defense systems. Hence there is a critical need to understand and quantify the effects of radiation on the present and next generation of nanoelectronic circuits, and to develop methods to render such circuits insensitive to radiation. In this project we intend to identify and characterize (as a function of device dimension if possible) the deleterious effects of radiation on nanoscale devices. More importantly, we intend to build on the standard models, which describe the effects of radiation, and develop software that would enable the modeling and simulation of radiation effects. First we will consider conventional nanoelectronic devices --- that is those where charge transport is based on the usual principles of drift and diffusion. Then a tool for the effects of radiation on single electron transistors and amplifiers (including those based on carbon nanotubes) would also be developed. Using the software, methods to mitigate the effects of radiation by rad-hard designs will be examined.
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NLDAS Noah Land Surface Model L4 Monthly 0.125 x 0.125 degree V002
nasa-test-0.demo.socrata.com | Last Updated 2015-07-20T04:56:05.000ZThis data set contains a series of land surface parameters simulated from the Noah land-surface model (LSM) for Phase 2 of the North American Land Data Assimilation System (NLDAS-2). The data are in 1/8th degree grid spacing and range from Jan 1979 to the present. The temporal resolution is monthly. The file format is WMO GRIB-1. The NLDAS-2 monthly Noah model data were generated from the NLDAS-2 hourly Noah model data, as monthly accumulation for rainfall, snowfall, subsurface runoff, surface runoff, total evapotranspiration, and snow melt, and monthly average for other variables. Monthly period of each month is from 00Z at start of the month to 23:59Z at end of the month, except the first month (Jan 1979) that starts from 00Z 02 Jan 1979. Also for the first month (Jan 1979), because the variables listed as instantaneous in the README file (http://hydro1.sci.gsfc.nasa.gov/data/s4pa/NLDAS/README.NLDAS2.pdf) do not have valid data exactly on 00Z 02 Jan 1979, and this one hour is not included in the average for this month only. Brief description about the NLDAS-2 monthly Noah model can be found from the GCMD DIF for GES_DISC_NLDAS_NOAH0125_H_V002 at http://gcmd.gsfc.nasa.gov/getdif.htm?GES_DISC_NLDAS_NOAH0125_H_V002. Details about the NLDAS-2 configuration of the Noah LSM can be found in Xia et al. (2012). The NLDAS-2 Noah monthly data contain fifty-two fields. The data set applies a user-defined parameter table to indicate the contents and parameter number. The GRIBTAB file (http://disc.sci.gsfc.nasa.gov/hydrology/grib_tabs/gribtab_NLDAS_NOAH.002.txt) shows a list of parameters for this data set, along with their Product Definition Section (PDS) IDs and units. For information about the vertical layers of the Soil Moisture Content (PDS 086), Soil Temperature (PDS 085), and Liquid Soil Moisture Content (PDS 151) please see the README Document at ftp://hydro1.sci.gsfc.nasa.gov/data/s4pa/NLDAS/README.NLDAS2.pdf or the GrADS ctl file at ftp://hydro1.sci.gsfc.nasa.gov/data/gds/NLDAS/NLDAS_NOAH0125_M.002.ctl.
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Extreme Temperature, Rad-Hard Power Management ASIC Project
nasa-test-0.demo.socrata.com | Last Updated 2015-07-20T05:14:50.000ZRidgetop Group will design a rad-hard Application Specific Integrated Circuit (ASIC) for spacecraft power management that is functional over a temperature range of -230 to +130 <SUP>o</SUP>C. This ASIC is intended to work in conjunction with a Fuel Cell power system and battery back-up to provide uninterrupted power to critical modules in Space. Ridgetop will combine Radiation Hardening (RH) techniques with Large Scale Integration (LSI) methodologies to build a power management system for spacecraft applications onto a single monolithic circuit. The significance of this innovation is a single reliable component (ASIC) that will meet platform requirements for high voltage, wide operating temperature range, and radiation tolerance (minimum 100 krads Total Ionizing Doze (TID), 100 MeVcm2/mg Single Event Latchup (SEL). During phase 1, we will select two functional blocks from within a representative NASA power management system as test cases. Designs for these blocks will be developed and validated through SPICE circuit and radiation simulations, using technology files provided by a commercial foundry. In phase 2, Ridgetop will deliver working prototype integrated circuits (ICs) that meet and exceed the above requirements.
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High Torque, Direct Drive Electric Motor Project
nasa-test-0.demo.socrata.com | Last Updated 2015-07-20T05:10:03.000ZBear Engineering proposes to advance the development of an innovative high torque, low speed, direct drive motor in order to meet NASA's requirements for such devices. Fundamentally, all electric motors basically work on the same electromagnetic principle: a tangential electromagnetic force attracts the rotor to the stator. Just when the rotor field is closest to the stator field and the electromagnetic attraction is greatest, the power is interrupted and another set of magnetic poles repeats the cycle. Furthermore, the two magnetically attracted elements never make contact, which would otherwise offer the highest force of attraction. The proposed novel motor design, successfully demonstrated at TRL 4 in Phase 1, operates and behaves entirely differently from all other known electric motor designs and is capable of producing incredibly high, direct drive torques at low rotational speeds. Its operational performance is similar to that of a stepper motor with a 1000:1 gearhead attached, but the similarity ends there. The motor is configured such that its length to diameter aspect ratio is opposite that of traditional motors as it has a relatively large diameter and short axial length; this offers all new packaging opportunities. The design also allows for a single, large diameter bearing pair to be used for the motor's output shaft which renders it stiff enough to directly mount the driven elements. The need for additional bearing supports and bearing mounting structure is thus eliminated. By the end of Phase 2, the system will be designed, developed and tested at TRL 6 with Mars environmental conditions.
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OMI/Aura Level 1B VIS Zoom-in Geolocated Earthshine Radiances 1-orbit L2 Swath 13x12 km V003
nasa-test-0.demo.socrata.com | Last Updated 2015-07-20T04:54:21.000ZThe Level-1B (L1B) Radiance Product OML1BRVZ (Version-3) from the Aura-OMI is now available (http://disc.gsfc.nasa.gov/Aura/OMI/oml1brvz_v003.shtml) to public from the NASA GSFC Earth Sciences Data and Information Services Center (GES DISC). OMI calibrated and geolocated radiances for the channels in the UV1 (264-311 nm), UV2 (307-383 nm)and VIS(349-504) regions, spectral irradiances, calibration measurements, and all derived geophysical atmospheric products are archived at the NASA Goddard DAAC. (The shortname for this OMI Level-1B Product is OML1BRVZ) The lead algorithm scientist for this product is Dr. Marcel Dobber from the KNMI. The OMI Level 1B Visible Radiance Zoom-in Product OML1BRVZ contains geolocated Earth view spectral radiances from the VIS channel detectors in the wavelength range of 349 to 504 nm. The product contains the measurements that are taken once a month using the spatial zoom-in measurement modes (30 pixels covering 750 km swath width). In spatial zoom in mode the nadir ground pixel size is 13 x 12 km2 and measurements are available only for the wavelengths 306 to 432 nm. OML1BRVZ files are stored in EOS Hierarchical Data Format (HDF-EOS 2.4) which is based on HDF4. The radiance for the earth measurements (also referred as signal) and its precision are stored as a 16 bit mantissa and an 8-bit exponent. The signal can be computed using the equation: signal = signal_mantissa x 10 exponent . For the precision, the same exponent is used as for the signal. Each file contains data from the day lit portion of an orbit (~53 minutes) and is roughly 570 MB in size. There are approximately 14 orbits per day.
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Modular, Fault-Tolerant Electronics Supporting Space Exploration Project
nasa-test-0.demo.socrata.com | Last Updated 2015-07-20T05:26:45.000ZModern electronic systems tolerate only as many point failures as there are redundant system copies, using mere macro-scale redundancy. Fault Tolerant Electronics Supporting Space Exploration (FTESSE) creates an electronic design paradigm using reprogrammable FPGAs to create swappable Circuit Object Blocks (COBs) ? analogous to software objects ? for the first time enabling redundancy on a micro-scale. The result is an increased tolerance of point failures by several orders of magnitude over traditional approaches. In the FTESSE approach, FPGAs are partitioned into COBs (groups of gates), each performing a specific function. Bad areas can be mapped like the bad sector data on a disk drive, enabling COBs to be placed in areas of working gates to recover system performance. Hardware tested during Phase I verified point failures could be introduced into an example circuit and corrected. As in the Phase I model, circuits to be monitored reside on a Slave FPGA, and a Master FPGA monitors outputs of all COBs, sensing faults and mapping non-working gates on the Slave FPGA. The Master is a rad-hard, triple mode redundancy (TMR) FPGA, but the Slaves need not be, opening the doors to higher performance applications while maintaining high levels of fault tolerance.
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High Torque, Direct Drive Electric Motor Project
nasa-test-0.demo.socrata.com | Last Updated 2015-07-20T05:14:32.000ZBear Engineering proposes to develop an innovative high torque, low speed, direct drive motor in order to meet NASA's requirements for such devices. Fundamentally, all electric motors basically work on the same electromagnetic principle: a tangential electromagnetic force attracts the rotor to the stator. Just when the rotor field is closest to the stator field and the electromagnetic attraction is greatest, the power is interrupted and another set of magnetic poles repeats the cycle. Furthermore, the two magnetically attracted elements never make contact, which would otherwise offer the highest force of attraction. The proposed novel motor design operates and behaves entirely differently from all other known electric motor designs and it will produce incredibly high, direct drive torques at low rotational speeds. Its operational performance is similar to that of a stepper motor with a 1000:1 gearhead attached, but the similarity ends there. The motor is configured such that its length to diameter aspect ratio is opposite that of traditional motors as it has a relatively large diameter and short axial length; this offers all new packaging opportunities. The proposed design also allows for a single, large diameter bearing pair to be used for the motor's output shaft which renders it stiff enough to directly mount the driven elements. The need for additional bearing supports and bearing mounting structure is thus eliminated. At the end of the proposed Phase 1 effort, the motor design will be at TRL 4 and by the end of a potential Phase 2, the system will be at TRL 6.