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Active Aircraft Pylon Noise Control System
Unmanned Aerial Systems Traffic Management
Method of Bonding Dissimilar Materials
Sonar Inspection Robot System
Applying the Dynamic Inertia Measurement Method to Full-Scale Aerospace Vehicles
Method and Apparatus for Measuring Surface Air Pressure
Fully Premixed, Low-Emission, High-Pressure, Multi-Fuel Burner
Self-Healing Wire Insulation
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Inert Welding/Brazing Gas Filters and Dryers

This system can be used in any process requiring reduction of inert-gas moisture level. A system has been designed to reduce the hydrogen molecule content in inert gases that are used for shielding the welding arc and molten weld area during the manual fusion, automated welding, and induction brazing process. Two desiccant pipeline dryer cartridges are connected together using either aircraft or KC .250 fittings, and are installed in-line between the inert-gas facility source (argon and helium) and the welding machine. This process helps maintain alloy grain structure and integrity to engineering specifications during the welding and brazing processes. Also, this method enhances weldability when joining similar and dissimilar alloys. It is easy to restore the system to original drying capabilities by using a nitrogen purge or by oven drying. This design has low schedule impact or down time when being installed on machines or in systems. There is also a sight glass to indicate when servicing is needed.

Posted in: Briefs, TSP, Manufacturing & Prototyping

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Fabricating Copper Nanotubes by Electrodeposition

Relative to copper nanorods, copper nanotubes can be fabricated at lower cost. Copper tubes having diameters between about 100 and about 200 nm have been fabricated by electrodeposition of copper into the pores of alumina nanopore membranes. Copper nanotubes are under consideration as alternatives to copper nanorods and nanowires for applications involving thermal and/or electrical contacts, wherein the greater specific areas of nanotubes could afford lower effective thermal and/or electrical resistivities. Heretofore, copper nanorods and nanowires have been fabricated by a combination of electrodeposition and a conventional expensive lithographic process. The present electrodeposition-based process for fabricating copper nanotubes costs less and enables production of copper nanotubes at greater rate.

Posted in: Briefs, Manufacturing & Prototyping

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Improved Fabrication of Ceramic Matrix Composite/Foam Core Integrated Structures

CMC face sheets bonded to ceramic foam cores are delamination-resistant and reduce cost, weight, and maintenance. The use of hybridized carbon/silicon carbide (C/SiC) fabric to reinforce ceramic matrix composite face sheets and the integration of such face sheets with a foam core creates a sandwich structure capable of withstanding high-heat-flux environments (150 W/cm2) in which the core provides a temperature drop of 1,000 °C between the surface and the back face without cracking or delamination of the structure. The composite face sheet exhibits a bilinear response, which results from the SiC matrix not being cracked on fabrication. In addition, the structure exhibits damage tolerance under impact with projectiles, showing no penetration to the back face sheet. These attributes make the composite ideal for leading-edge structures and control surfaces in aerospace vehicles, as well as for acreage thermal protection systems and in high-temperature, lightweight stiffened structures.

Posted in: Briefs, TSP, Manufacturing & Prototyping

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Reducing Aerodynamic Drag on Empty Open Cargo Vehicles

Open cargo bays are subdivided by means of simple partitions. Some simple structural modifications have been demonstrated to be effective in reducing aerodynamic drag on vehicles that have empty open cargo bays. The modifications were originally intended to be made in railroad coal cars because the amounts of coal and the distances over which they are transported by railroad in the United States are so large that the resulting reduction in drag could, potentially, result in an annual saving of millions of gallons of diesel fuel.

Posted in: Briefs, Mechanical Components, Mechanics

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Rotary Percussive Auto-Gopher for Deep Drilling and Sampling

A drilling/sampling apparatus braces itself against the side of the hole. The term “rotary percussive autogopher” denotes a proposed addition to a family of apparatuses, based on ultrasonic/sonic drill corers (USDCs), that have been described in numerous previous NASA Tech Briefs articles. These apparatuses have been designed, variously, for boring into, and/or acquiring samples of, rock or other hard, brittle materials of geological interest. In the case of the rotary percussive auto-gopher, the emphasis would be on developing an NTB 05Mech/Mach 0809:Layout 1 7/20/09 9:54 AM Page 38 apparatus capable of penetrating to, and acquiring samples at, depths that could otherwise be reached only by use of much longer, heavier, conventional drilling-and-sampling apparatuses.

Posted in: Briefs, TSP, Mechanical Components, Mechanics

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Thermostatic Valves Containing Silicone-Oil Actuators

Flow-splitting and flow-mixing thermally actuated spool valves have been developed for controlling flows of a heat-transfer fluid in a temperature-regulation system aboard the Mars Science Laboratory (MSL) rover. Valves like these could also be useful in terrestrial temperature-regulation systems, including automobile air- conditioning systems and general refrigeration systems. These valves are required to provide smoother actuation over a wider temperature range than the flow-splitting, thermally actuated spool valves used in the Mars Explorer Rover (MER). Also, whereas the MER valves are unstable (tending to oscillate) in certain transition temperature ranges, these valves are required not to oscillate.

Posted in: Briefs, Mechanical Components, Mechanics

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Assembly Machines Produce Optics for NASA’s NuSTAR Telescope

Cylindrical optics module assembly machines ABTech Swanzey, NH 603-358-6431 www.abtechmfg.com ABTech has completed the first of two cylindrical optics module assembly machines for Columbia University’s Nevis Astrophysics Laboratory. The multi-axis air bearing machine platforms are optimized for the construction of high-energy xray telescopes. The optics modules will be used to produce the telescope optics for NASA’s NuSTAR (Nuclear Spectroscopic Telescope Array) program. ABTech will provide installation and on-sight operational training to Columbia University scientists at the Nevis Laboratory and ongoing technical support during the production of the optics modules.

Posted in: Application Briefs

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