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Briefs: Mechanical & Fluid Systems
Positioning System for a Human Habitat in a Large Centrifuge
A report describes the system for controlling the radial position and tilt of a spacecraftlike habitat for humans in NASA's Space Flight Environmental Simulator (SFES) — a 16-m-diameter centrifuge used previously to evaluate effects of hypergravitational acceleration on animals....
Briefs: Mechanical & Fluid Systems
Launch-on-Demand Servicing Microsatellites
A report describes an emerging class of miniature, highly capable, relatively inexpensive satellites that could be launched rapidly by nontraditional methods. Of particular interest is a subclass of proposed launch-on-demand microsatellites for inspecting and servicing other satellites (targets)...
Briefs: Physical Sciences
First-Generation Integrated Free-Flying Micro-Spacecraft
The concept of free-flying micro-spacecraft was to develop a miniature spacecraft system fully integrated with a scientific sensor. A fleet of such tiny spacecraft would be deployed in space for multi-probe measurements of a three-dimensional phenomenon and to separate the spatial/temporal...
Briefs: Mechanical & Fluid Systems
Miniature Electrothermal Thruster
A report proposes a miniature electrothermal spacecraft engine. The engine would include a chamber with an inside length of ≈1.5 cm and inside diameter of ≈0.25 cm, with a dielectric (ideally diamond) sidewall lining, a metal-coated expansion nozzle at one end, and a metal electrode at the other end. A...
Briefs: Medical
Using Photosynthetic Bacteria To Make Oxygen on Mars
A report presents a proposal to harness photosynthetic bacteria to generate essential materials needed during human and robotic exploration on the surface of Mars. Utilizing an extremely small amount of H2O and an ample amount of CO2 (and N2 and/or other elements and compounds) already...
Briefs: Physical Sciences
DNS of a Transitional Supercritical C7H16/N2 Mixing Layer
This report discusses direct numerical simulations (DNS) of a mixing layer, between a nitrogen stream and a heptane stream initially flowing at different velocities, under supercritical conditions and undergoing a transition to turbulence. Thermodynamically, supercritical conditions...
Briefs: Photonics/Optics
The figure depicts the optical layout and meridional-plane ray-trace diagram of a four-element superachromatic near-infrared (IR) lens system. The system features a 30-mm-diameter...
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Briefs: Motion Control
A proposed robotic apparatus for underground exploration would propel itself downward in a percussive manner reminiscent of a jackhammer, pile driver, or hammer-and-chisel combination. Called...
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Briefs: Photonics/Optics
Software for Multidisciplinary Concurrent Optical Design
The Integrated Optical Design Analyzer (IODA) is a computer program that facilitates multidisciplinary concurrent engineering of highly precise optical instruments. (IODA should not be confused with a multidisciplinary optical-system-analysis program, called "IMOS," that has been reported...
Briefs: Robotics, Automation & Control
A robotic apparatus equipped with ultrasonic probes and other instrumentation has been proposed to reduce the danger and cost and increase the speed of searching for land mines. The apparatus...
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Briefs: Photonics/Optics
An optical assembly that combines the output of mutually incoherent lasers into a multibeam source for transmission into free space was designed, assembled, and tested. This design was motivated by the need for...
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Briefs: Motion Control
Software for Selecting Modes of Vibration of a Structure
A computer program facilitates the selection of the dominant modes of vibration of a structure - especially the dominant modes that interact with specific locations on the structure. This program is intended for use in conjunction with any of the various vibration-mode-analysis programs...
Briefs: Photonics/Optics
Improved Fiber-Pigtailed Non-Planar Ring Oscillator Laser
An improved non-planar ring oscillator (NPRO) of the fiber-pigtailed type has been developed. The improvements over prior lasers of this type lie in details of design and construction that are intended to enhance mechanical stability and thereby increase the stability of optical...
Briefs: Photonics/Optics
Computing Atmospheric Profiles From Spectral Measurements
The SEASCRAPE computer program estimates the composition, temperature, and pressure of the atmosphere as a function of position by fitting remote-sounding spectroscopic data to a mathematical model of the transfer of radiation through the atmosphere. SEASCRAPE consists of two integrated...
Briefs: Photonics/Optics
Design and development of miniature paraboloidal mirrors that would be deflected magnetically to vary their radii of curvature (and thus their focal lengths)...
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Briefs: Motion Control
Miniature electroactive-polymer rakes (MEARs) are undergoing development for eventual use as simple, lightweight, inexpensive low-power-consumption devices that would remove soil, dust, and/or other loose...
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Briefs: Motion Control
Engineers at Johnson Space Center have invented a relatively inexpensive, lightweight device that provides vibrational and thermal isolation for low-power electronic equipment. The...
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Briefs: Photonics/Optics
Study of Stitching Errors in Shot-Shifted E-Beam Lithography
A report presents a study of the efficacy of shot shifting for reducing stitching errors in diffraction gratings made by electron-beam (E-beam) lithography. Stitching errors arise from fabricating a grating as a mosaic of smaller gratings by frequently translating the grating blank....
Briefs: Software
Software for Automated Ortho-Rectification of SAR Images
The Automated SAR Ortho-rectification Software System enables users of synthetic-aperture-radar (SAR) data to form processed images that are free of the distortion caused by the SAR imaging geometry and topography. The software consists of four modules:
Briefs: Mechanical & Fluid Systems
The term "actuated ball-and-socket" (ABS) characterizes a proposed class of ball-and-socket joints that would incorporate ultrasonic motors and other piezoelectric actuators to generate multidimensional...
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Briefs: Materials
Experiments have shown that ultrasound could be an effective means of enhancing the removal of chlorinated hydrocarbon contaminants from groundwater by the zero-valent-metal treatment...
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Briefs: Mechanical & Fluid Systems
The magnetic/extendible boom docking aid is an improved mechanism that enables two spacecraft to capture and structurally mate with each other without inducing the large (and...
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Briefs: Mechanical & Fluid Systems
Vapor-Compression Solar Refrigerator Without Batteries
A solar-powered vapor-compression refrigeration system developed for Johnson Space Center operates without batteries. The design of this system will make the cost of solar-powered refrigeration systems competitive and enable the use of such systems in long-distance spaceflights, military field...
Briefs: Manufacturing & Prototyping
Thermal-Stress Technique for Cutting Thin Glass Sheets
A technique based on the generation of highly localized thermal stresses has been devised as a means of cutting both flat and curved glass sheets of thicknesses between 30 and 600 µm. The technique is reliable, accurate, and economical. The technique can be used, for example, to cut thin glass...
Briefs: Medical
The microwave-sterilizable access port is an apparatus that functions in a simple, quick, and reliable manner to reduce significantly the risk of contamination during transfer of materials into or out of...
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Briefs: Medical
Treatment With Ferrates Eliminates DNA and Proteins
Ferrate (VI) salts have been proposed for use in sterilizing water (perhaps also in sterilizing air). The iron in ferrate (VI) salts is in its highest oxidation state (VI), and these salts are extremely strong oxidants. In laboratory experiments, it was shown that treatment of DNA solutions with...
Briefs: Physical Sciences
All-Pressure Fluid-Drop Model Applied to a Binary Mixture
A report presents a computational study of the subcritical and supercritical behaviors of a drop of heptane surrounded by nitrogen, using the fluid-drop model described in "Model of a Drop of O2 Surrounded by H2 at High Pressure" (NPO-20220) and "The Lewis Number Under Supercritical...
Briefs: Physical Sciences
Validation of All-Pressure Fluid-Drop Model
A report presents a computational study of the subcritical and supercritical behaviors of a drop of heptane surrounded by nitrogen. The subject matter is basically same as that of the report described in the preceding article, except that the Lewis-number issue is not addressed in detail; however, this...
Briefs: Information Technology
Generating Commands for the Mars Polar Lander Robotic Arm
A report discusses the use of the Web Interface for Telescience (WITS) for visualization and command sequence generation in the Mars Polar Lander (MPL) mission. WITS, which has been described in prior articles in NASA Tech Briefs, is an Internet-based software system that enables...

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