Vehicles and Performance

Aerodynamics

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Briefs: Information Technology
Chance-Constrained Guidance With Non-Convex Constraints
Missions to small bodies, such as comets or asteroids, require autonomous guidance for descent to these small bodies. Such guidance is made challenging by uncertainty in the position and velocity of the spacecraft, as well as the uncertainty in the gravitational field around the small body. In...
Briefs: Green Design & Manufacturing
This innovation from Goddard Space Flight Center is an antibacterial, anti-contamination, and self-cleaning coating that...
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Briefs: Physical Sciences
Method for Measuring Collimator-Pointing Sensitivity to Temperature Changes
For a variety of applications, it is important to measure the sensitivity of the pointing of a beam emerging from a collimator, as a function of temperature changes. A straightforward method for carrying out this measurement is based on using interferometry for monitoring...
Briefs: Physical Sciences
Super Dwarf Wheat for Growth in Confined Spaces
USU-Perigee is a dwarf red spring wheat that is a hybrid of a high-yield early tall wheat (USU-Apogee) and a low-yield, extremely short wheat that has poor agronomic characteristics. USU-Perigee was selected for its extremely short height (≈0.3 m) and high yield — characteristics that make it...
Briefs: Electronics & Computers
Reliability of Ceramic Column Grid Array Interconnect Packages Under Extreme Temperatures
A paper describes advanced ceramic column grid array (CCGA) packaging interconnects technology test objects that were subjected to extreme temperature thermal cycles. CCGA interconnect electronic package printed wiring boards (PWBs) of polyimide were...
Briefs: Software
MASCOT — MATLAB Stability and Control Toolbox
MASCOT software was created to provide the conceptual aircraft designer accurate predictions of air vehicle stability and control characteristics. The code takes as input mass property data in the form of an inertia tensor, aerodynamic loading data, and propulsion (i.e. thrust) loading data. Using...
Briefs: Physical Sciences
This miniature or micro-sized semi-conductor sensor design provides direct, nonintrusive measurement of skin friction or wall shear stress in fluid flow situations in a...
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Briefs: Physical Sciences
Correction for Self-Heating When Using Thermometers as Heaters in Precision Control Applications
In precision control applications, thermometers have temperature-dependent electrical resistance with germanium or other semiconductor material thermistors, diodes, metal film and wire, or carbon film resistors. Because resistance readout requires...
Briefs: Information Technology
Small-Scale Dissipation in Binary-Species Transitional Mixing Layers
Motivated by large eddy simulation (LES) modeling of supercritical turbulent flows, transitional states of databases obtained from direct numerical simulations (DNS) of binary-species supercritical temporal mixing layers were examined to understand the subgrid-scale dissipation,...
Briefs: Materials
Lightweight, Ultra-High-Temperature, CMC-Lined Carbon/Carbon Structures
lished engineering material used extensively in aerospace. The beneficial properties of C/C include high strength, low density, and toughness. Its shortcoming is its limited usability at temperatures higher than the oxidation temperature of carbon — approximately 400 °C....
Briefs: Software
Distributed Aerodynamic Sensing and Processing Toolbox
A Distributed Aerodynamic Sensing and Processing (DASP) toolbox was designed and fabricated for flight test applications with an Aerostructures Test Wing (ATW) mounted under the fuselage of an F-15B on the Flight Test Fixture (FTF). DASP monitors and processes the aerodynamics with the...
Briefs: Manufacturing & Prototyping
Nanoscale Deformable Optics
Several missions and instruments in the conceptual design phase rely on the technique of interferometry to create detectable fringe patterns. The intimate emplacement of reflective material upon electron device cells based upon chalcogenide material technology permits high-speed, predictable deformation of the reflective...
Briefs: Physical Sciences
Active Flow Effectors for Noise and Separation Control
New flow effector technology for separation control and enhanced mixing is based upon shape memory alloy hybrid composite (SMAHC) technology. The technology allows for variable shape control of aircraft structures through actively deformable surfaces. The flow effectors are made by embedding...
Briefs: Information Technology
Rapid Calculation of Spacecraft Trajectories Using Efficient Taylor Series Integration
A variable-order, variable-step Taylor series integration algorithm was implemented in NASA Glenn’s SNAP (Spacecraft N-body Analysis Program) code. SNAP is a high-fidelity trajectory propagation program that can propagate the trajectory of a spacecraft about...
Briefs: Photonics/Optics
An innovation reported in “Two-Camera Acquisition and Tracking of a Flying Target,” NASA Tech Briefs, Vol. 32, No. 8 (August 2008), p. 20, used a commercial fish-eye lens and an...
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Articles: Software
SolidWorks 3D Design SoftwareDassault Systèmes SolidWorks Corp.Concord, MA800-693-9000www.solidworks.com Software from Dassault Systèmes SolidWorks Corp. has been used by engineering service...
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Briefs: Electronics & Computers
Diamond Heat-Spreader for Submillimeter-Wave Frequency Multipliers
The planar GaAs Shottky diode frequency multiplier is a critical technology for the local oscillator (LO) for submillimeter-wave heterodyne receivers due to low mass, tenability, long lifetime, and room-temperature operation. The use of a W-band (75–100 GHz) power amplifier...
Briefs: Mechanical & Fluid Systems
Pyrotechnic Actuator for Retracting Tubes Between MSL Subsystems
NASA’s Jet Propulsion Laboratory, Pasadena, California An apparatus, denoted the “retractuator” (a contraction of “retracting actuator”), was designed to help ensure clean separation between the cruise stage and the entry-vehicle subsystem of the Mars Science Laboratory...
Briefs: Materials
Modeling of Alkane Oxidation Using Constituents and Species
It is currently not possible to perform simulations of turbulent reactive flows due in particular to complex chemistry, which may contain thousands of reactions and hundreds of species. This complex chemistry results in additional differential equations, making the numerical solution of...
Briefs: Electronics & Computers
Grid-Sphere Electrodes for Contact With Ionospheric Plasma
Grid-sphere electrodes have been proposed for use on the positively biased end of electrodynamic space tethers. A grid-sphere electrode is fabricated by embedding a wire mesh in a thin film from which a spherical balloon is formed. The grid-sphere electrode would be deployed from compact...
Briefs: Mechanical & Fluid Systems
A new sampler is similar to a common snow blower, but is robust and effective in sample collection. The brush wheels are arranged in a triangle shape, each driven by a brushless DC motor and planetary gearhead...
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Briefs: Mechanical & Fluid Systems
Handling Qualities Prediction of an F-16XL-Based Reduced Sonic Boom Aircraft
A major goal of the Supersonics Project under NASA’s Fundamental Aeronautics program is sonic boom reduction of supersonic aircraft. An important part of this effort is development and validation of sonic boom prediction tools used in aircraft design. NASA Dryden’s...
Briefs: Mechanical & Fluid Systems
Counterflowing Jet Subsystem Design
A counterflowing jet design (a spacecraft and trans-atmospheric subsystem) employs centrally located, supersonic cold gas jets on the face of the vehicle, ejecting into the oncoming free stream. Depending on the supersonic free-stream conditions and the ejected mass flow rate of the counterflowing jets, the bow...
Briefs: Information Technology
Determining Atmospheric-Density Profile of Titan
A method was developed for measuring the atmospheric density of Titan, the largest moon of Saturn, to create an accurate density profile as a function of altitude. This will allow mission planners to select safe flyby altitudes, and for navigation engineers to accurately predict the delta-v...
Briefs: Physical Sciences
True Shear Parallel Plate Viscometer
This viscometer (which can also be used as a rheometer) is designed for use with liquids over a large temperature range. The device consists of horizontally disposed, similarly sized, parallel plates with a precisely known gap. The lower plate is driven laterally with a motor to apply shear to the liquid in the...
Briefs: Materials
Silica/Polymer and Silica/Polymer/Fiber Composite Aerogels
Aerogels that consist, variously, of neat silica/polymer alloys and silica/polymer alloy matrices reinforced with fibers have been developed as materials for flexible thermal-insulation blankets. In comparison with prior aerogel blankets, these aerogel blankets are more durable and less...
Briefs: Mechanical & Fluid Systems
Dedicated Deployable Aerobraking Structure
A dedicated deployable aerobraking structure concept was developed that significantly increases the effective area of a spacecraft during aerobraking by up to a factor of 5 or more (depending on spacecraft size) without substantially increasing total spacecraft mass. Increasing the effective aerobraking...
Briefs: Energy
Most wind farms consist of horizontal axis wind turbines (HAWTs), but an alternative paradigm for wind energy extraction is found in vertical axis wind turbine (VAWT) designs. A single spatially-isolated VAWT has a significantly lower power coefficient.
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Briefs: Software
Parachute Drag Model
DTV-SIM is a computer program that implements a mathematical model of the flight dynamics of a missile-shaped drop test vehicle (DTV) equipped with a multistage parachute system that includes two simultaneously deployed drogue parachutes and three main parachutes deployed subsequently and simultaneously by use of pilot...

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