Stories

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Briefs: Semiconductors & ICs
In a proposed improvement in complementary metal oxide/semi con ductor (CMOS) image detectors, two additional implants in each pixel would effect vertical isolation between the metal oxide/...
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Briefs: Information Technology
Converting From DDOR SASF to APF
A computer program called “ddor_sasf2apf” converts delta-door (delta differential one-way range) request from an SASF (spacecraft activity sequence file) format to an APF (apgen plan file) format for use in the Mars Reconnaissance Orbiter (MRO) mission-planning-and- sequencing process. The APF is used as an...
Briefs: Information Technology
Converting From CVF to AAF
A computer program called “dsn config converter” automates what had been a manual process for updating the multi-mission adaptation file (multi.aaf) used by a multiple- mission- command- sequence- generating process comprised of a combination of the AUTOGEN and APGEN programs mentioned in the immediately preceding...
Briefs: Information Technology
Documenting AUTOGEN and APGEN Model Files
A computer program called “autogen hypertext map generator” satisfies a need for documenting and assisting in visualization of, and navigation through, model files used in the AUTOGEN and APGEN software mentioned in the two immediately preceding articles. This program parses autogen script files,...
Briefs: Information Technology
Sequence History Update Tool
The Sequence History Update Tool performs Web-based sequence statistics archiving for Mars Reconnaissance Orbiter (MRO). Using a single UNIX command, the software takes advantage of sequencing conventions to automatically extract the needed statistics from multiple files. This information is then used to populate a PHP...
Briefs: Software
Extraction and Analysis of Display Data
The Display Audit Suite is an integrated package of software tools that partly automates the detection of Portable Computer System (PCS) Display errors. [PCS is a laptop computer used onboard the International Space Station (ISS).] The need for automation stems from the large quantity of PCS displays (6,000+,...
Briefs: Information Technology
MRO DKF Post-Processing Tool
This software tool saves time and reduces risk by automating two labor-intensive and error- prone post-processing steps required for every DKF [DSN (Deep Space Network) Keyword File] that MRO (Mars Reconnaissance Orbiter) produces, and is being extended to post-process the corresponding TSOE (Text Sequence Of Events) as...
Briefs: Software
Rig Diagnostic Tools
Rig Diagnostic Tools is a suite of applications designed to allow an operator to monitor the status and health of complex networked systems using a unique interface between Java applications and UNIX scripts. The suite consists of Java applications, C scripts, VxWorks applications, UNIX utilities, C programs, and configuration...
Briefs: Information Technology
MRO Sequence Checking Tool
The MRO Sequence Checking Tool program, mro_check, automates significant portions of the MRO (Mars Reconnaissance Orbiter) sequence checking procedure. Though MRO has similar checks to the ODY's (Mars Odyssey) Mega Check tool, the checks needed for MRO are unique to the MRO spacecraft.
Briefs: Information Technology
Science Activity Planner for the MER Mission
The Maestro Science Activity Planner is a computer program that assists human users in planning operations of the Mars Explorer Rover (MER) mission and visualizing scientific data returned from the MER rovers. Relative to its predecessors, this program is more powerful and easier to use. This program is...
Briefs: Information Technology
UAVSAR Flight-Planning System
A system of software partly automates planning of a flight of the Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) — a polarimetric synthetic-aperture radar system aboard an unpiloted or minimally piloted airplane. The software constructs a flight plan that specifies not only the intended flight path...
Briefs: Manufacturing & Prototyping
Templates for fabricating sharply pointed microscopic peaks arranged in nearly regular planar arrays can be fabricated by a relatively inexpensive technique that has recently been...
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Briefs: Materials
Improved crucibles consisting mainly of metal-reinforced ceramic ampules have been developed for use in experiments in which material specimens are heated in the crucibles to various high temperatures,...
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Briefs: Materials
Adjustable Membrane Mirrors Incorporating G-Elastomers
Lightweight, flexible, large-aperture mirrors of a type being developed for use in outer space have unimorph structures that enable precise adjustment of their surface figures. A mirror of this type includes a reflective membrane layer bonded with an electrostrictive grafted elastomer...
Briefs: Materials
High-Temperature Crystal-Growth Cartridge Tubes Made by VPS
Cartridge tubes for use in a crystal-growth furnace at temperatures as high as 1,600°C have been fabricated by vacuum plasma spraying (VPS). These cartridges consist mainly of an alloy of 60 weight percent molybdenum with 40 weight percent rhenium, made from molybdenum powder coated...
Briefs: Materials
Hall-Effect Thruster Utilizing Bismuth as Propellant
A laboratory-model Hall-effect spacecraft thruster was developed that utilizes bismuth as the propellant. Xenon was used in most prior Hall-effect thrusters. Bismuth is an attractive alternative because it has a larger atomic mass, a larger electron- impact- ionization cross-section, and is...
Briefs: Materials
Applying an electric current to specially coated glass results in radiant heat energy. This process creates a transparent heating element with near- uniform surface temperatures. Manufacturing the...
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Briefs: Mechanical & Fluid Systems
An apparatus is being developed for sampling water for signs of microbial life in an ocean hydrothermal vent at a depth of as much as 6.5 km. Heretofore, evidence of microbial life in deep-sea hydrothermal...
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Briefs: Mechanical & Fluid Systems
Mars Rocket Propulsion System
A report discusses the methane and carbon monoxide/LOX (McLOx) rocket for ascent from Mars as well as other critical space propulsion tasks. The system offers a specific impulse over 370 s — roughly 50 s higher than existing space-storable bio- propellants. Current Mars in-situ propellant production (ISPP)...
Briefs: Mechanical & Fluid Systems
Two-Stage Passive Vibration Isolator
The design and testing of a structural system were implemented to hold the optics of the planned Space Interferometry Mission (SIM) at positions and orientations characterized by vibrational translation and rotation errors of no more than a few nanometers or a few milliarcseconds, respectively. Much of the...
Briefs: Physical Sciences
Altimetry Using GPS-Reflection/Occultation Interferometry
A Global Positioning System (GPS)- reflection/occultation interferometry was examined as a means of altimetry of water and ice surfaces in polar regions. In GPS- reflection/occultation interferometry, a GPS receiver aboard a satellite in a low orbit around the Earth is used to determine the...
Briefs: Mechanical & Fluid Systems
Improved Thermal Design of a Compression Mold
A compression tool used to make 1-in. (2.5-cm) diameter disks of high-temperature polymers was designed to be shorter and of larger diameter than conventional tools to reduce heat loss to the surrounding air, thus making more efficient use of applied heat. This system is less sensitive to the amount and...
Briefs: Mechanical & Fluid Systems
Enhanced Pseudo-Waypoint Guidance for Spacecraft Maneuvers
An enhanced version of the scheme reported in “Pseudo-Waypoint Guidance for Proximity Spacecraft Maneuvers” (NPO-42753), NASA Tech Briefs, Vol. 31, No. 6 (June 2007), page 73 was developed. To recapitulate: the scheme provides algorithms for guidance and control (G&C) of a...
Briefs: Physical Sciences
Thermally Driven Josephson Effect
A concept is proposed of the thermally driven Josephson effect in superfluid helium. Heretofore, the Josephson effect in a superfluid has been recognized as an oscillatory flow that arises in response to a steady pressure difference between two superfluid reservoirs separated by an array of submicron-sized...
Briefs: Physical Sciences
A method of using ellipsometry or polarization analysis of light in total internal reflection of a surface to determine the number density of gold nanoparticles on a smooth substrate...
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Briefs: Physical Sciences
Gold Nanoparticle Labels Amplify Ellipsometric Signals
The ellipsometric method reported in the immediately preceding article was developed in conjunction with a method of using gold nanoparticles as labels on biomolecules that one seeks to detect. The purpose of the labeling is to exploit the optical properties of the gold nanoparticles in order...
Briefs: Physical Sciences
Perturbation Effects on a Supercritical C₇H₁₆/N₂ Mixing Layer
This report presents a computational-simulation study of effects of perturbation wavelengths and initial Reynolds numbers on the transition to turbulence of a heptane/nitrogen mixing layer at supercritical pressure. The governing equations for the simulations were the same as...
Briefs: Information Technology
Schema for Spacecraft-Command Dictionary
An Extensible Markup Language (XML) schema was developed as a means of defining and describing a structure for capturing spacecraft command-definition and tracking information in a single location in a form readable by both engineers and software used to generate software for flight and ground systems. A...
Briefs: Information Technology
Self-Adjusting Hash Tables for Embedded Flight Applications
A common practice in computer science to associate a value with a key is to use a class of algorithms called a hash-table. These algorithms enable rapid storage and retrieval of values based upon a key. This approach assumes that many keys will need to be stored immediately. A new set of...

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