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Lightweight, Flexible Thermal Protection System for Fire Protection
High-Precision Electric Gate for Time-of-Flight Ion Mass Spectrometers
Polyimide Wire Insulation Repair System
Distributed Propulsion Concepts and Superparamagnetic Energy Harvesting Hummingbird Engine
Aerofoam
Wet Active Chevron Nozzle for Controllable Jet Noise Reduction
Magnetic Relief Valve
Active Aircraft Pylon Noise Control System
Unmanned Aerial Systems Traffic Management
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One-Micron (1064-nm) Planar External Cavity Laser (PLANEX)

Ahighly reliable, very low-phase, and low-amplitude-noise laser is required as an oscillator for the LISA mission. A commercial product made by Redfern Integrated Optics met these requirements (1550-nm PLANEX External Cavity Laser), but it operated at 1.5 microns, not the required LISA wavelength of 1 micron. An ultra-low-noise External Cavity Laser was produced at a wavelength of 1 micron, and was integrated in a butterfly package. The goal is to eventually use this laser in the LISA and GRACE-II missions.

Posted in: Briefs, Imaging, Photonics

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Stereoscopic Imaging in Hypersonic Boundary Layers Using Planar Laser-Induced Fluorescence

This technique offers a more complete visualization of high-speed flowfields than standard imaging methods.Stereoscopic time-resolved visualization of three-dimensional structures in a hypersonic flow was performed for the first time in NASA Langley Research Center’s 31-inch Mach 10 Air Tunnel. Nitric oxide (NO) was seeded into hypersonic boundary layer flows that were designed to transition from laminar to turbulent. A laser excitation and multiple-camera imaging scheme was used to obtain raw images containing three-dimensional spatial information. The images were processed in a computer visualization environment to provide stereoscopic image pairs that could be viewed several ways, including using the cross-eyed viewing method, with the aid of a stereoscope, as animated image pairs (i.e., wiggle stereoscopy), or as anaglyph images through conventional red/blue 3D glasses.

Posted in: Briefs, Imaging, Photonics

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Compact, Lightweight, Athermal, Nanocomposite Telescopes with Freeform Optics

Small space missions such as CubeSats frequently require telescopes with highly sophisticated optical systems that are also low in mass and cost. The very limited spacecraft volume and mass limits also preclude adjustments to maintain critical alignment with change in temperature. Existing systems, especially those that employ folded optical paths with freeform optics, are expensive to fabricate. The optics, and support and metering structures, are also heavy due to the use of high-density material such as glass, aluminum, or nickel.

Posted in: Briefs, Imaging, Optics, Photonics

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Variably Transmittive, Electronically Controlled Eyewear

This technology can be used in pilot glasses, military goggles, gaming and virtual reality, and transition lenses for eyewear.During instrument flight training, the pilot must have his/her view through the aircraft windscreen restricted to simulate low-visibility conditions while permitting the pilot to view the instrument panel. In one current method, a hood is draped across the aircraft windscreen, or a face mask or blackened glasses are worn by the pilot. All such current methods create potentially hazardous disorientation and an unnatural environment for the trainee. In particular, the face mask and blackened glasses restrict the pilot’s peripheral vision, and require uncomfortable and unnatural head positions in order to see the entire instrument panel.

Posted in: Briefs, Instrumentation

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Method for Ground-to-Satellite Laser Calibration System

NASA’s Langley Research Center has developed the Ground-to-Space Laser Calibration (GSLC) system concept for calibrating Earth observing sensors measuring reflected radiance. GSLC is capable of calibrating sensitivity to polarization, degradation of optics, and response to stray light of spaceborne reflected solar sensors. The concept is based on using an accurate ground-based laser system pointing at and tracking the instrument on orbit during nighttime and clear atmosphere conditions. The GSLC system will be applicable to instrument calibration in both low Earth and geostationary Earth orbits.

Posted in: Briefs, Instrumentation

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Energy Analysis Method for Hidden Damage Detection

Better understanding of composite damage could eliminate unnecessary repairs and help prevent catastrophic in-service failure.NASA’s Langley Research Center has developed a new Non-Destructive Testing (NDT) method for identifying and characterizing hidden damage in composite materials. The new technique requires only single-sided access to the test specimen, and uses trapped energy analysis to detect and characterize damage that was previously ob - scured. Current methods, usually ultrasound or laser ultrasound, cannot characterize imperfections below or hidden by near surface damage. The new method uses 3D custom ultrasonic simulation tools to study ultrasonic guided wave behavior and energy trapping due to multilayer delamination damage (Figure 1).

Posted in: Briefs, Instrumentation

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Deconvolution Methods and Systems for the Mapping of Acoustic Sources from Phased Microphone Arrays

This technology provides noise location and strength diagnostics for mechanical and aerodynamic systems.NASA’s Langley Research Center researchers developed DAMAS using an iterative algorithm to deconvolute noise signals, allowing for more accurate quantification of the position and strength of acoustic sources. Recent development of the DAMAS microphone phased array processing methodology allows the determination and separation of coherent and incoherent noise source distributions. The DAMAS technology represents a significant breakthrough in the field of aero-acoustics.

Posted in: Briefs, Instrumentation

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