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Mechanoresponsive Healing Polymers
Variable Permeability Magnetometer Systems and Methods for Aerospace Applicationst
Evaluation Standard for Robotic Research
Small Robot Has Outstanding Vertical Agility
Smart Optical Material Characterization System and Method
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
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Switched Band-Pass Filters for Adaptive Transceivers

Switched filters could be reconfigured to conform to diverse standards. Switched band-pass filters are key components of proposed adaptive, software- defined radio transceivers that would be parts of envisioned digital-data- communication networks that would enable real-time acquisition and monitoring of data from geographically distributed sensors. Examples of sensors to be connected to such networks include security cameras, radio-frequency identification units, and geolocation units based on the Global Positioning System. Through suitable software configuration and without changing hardware, these transceivers could be made to operate according to any of a number of complex wireless-communication standards that could be characterized by diverse modulation schemes, bandwidths, and data-handling protocols.

Posted in: Briefs, Electronics & Computers

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Loss-of-Control-Inhibitor Systems for Aircraft

Excessive commands are resisted by feedback in the form of damping forces. Systems to provide improved tactile feedback to aircraft pilots are being developed to help the pilots maintain harmony between their control actions and the positions of aircraft control surfaces, thereby helping to prevent loss of control. A system of this type, denoted a loss-of-control-inhibitor system (LOCIS) can be implemented as a relatively simple addition to almost any pre-existing flight-control system. The LOCIS concept offers at least a partial solution to the problem of (1) keeping a pilot aware of the state of the control system and the aircraft and (2) maintaining sufficient control under conditions that, as described below, have been known to lead to loss of control.

Posted in: Briefs, Electronics & Computers

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Four-Way Ka-Band Power Combiner

A prior X-band design has been adapted to Ka band. The Power Combiner Structure has five ports, of which four are used for input and one for output. Thisis a simplified cross-sectional view: holes for fastening and cooling are omitted for the sake of clarity.A waveguide structure for combining the outputs of four amplifiers operating at 35 GHz (Ka band) is based on a similar prior structure used in the X band. The structure is designed to function with low combining loss and low total reflected power at a center frequency of 35 GHz with a 160 MHz bandwidth.

Posted in: Briefs, TSP, Electronics & Computers

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Waveguide Calibrator for Multi-Element Probe Calibration

Acoustic waveguide technology produces the same acoustic field at each of the sensing elements. A calibrator, referred to as the “spider” design, can be used to calibrate probes incorporating multiple acoustic sensing elements. The application is an acoustic energy density probe, although the calibrator can be used for other types of acoustic probes. The calibrator relies on the use of acoustic waveguide technology to produce the same acoustic field at each of the sensing elements. As a result, the sensing elements can be separated from each other, but still calibrated through use of the acoustic waveguides.

Posted in: Briefs, Electronics & Computers

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High-Voltage Power Supply With Fast Rise and Fall Times

Output is electronically programmable and electronically switchable. A special-purpose high-voltage power supply can be electronically switched on and off with fast rise and fall times, respectively. The output potential is programmable from 20 to 1,250 V. An output current of 50 μA can be sustained at 1,250 V. The power supply was designed specifically for electronically shuttering a microchannel plate in an x-ray detector that must operate with exposure times as short as 1 ms. The basic design of the power supply is also adaptable to other applications in which there are requirements for rapid slewing of high voltages.

Posted in: Briefs, Electronics & Computers

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Noncoherent DTTLs for Symbol Synchronization

At high signal-to-noise ratios, performances would approach those of coherent DTTLs. Noncoherent data-transition tracking loops (DTTLs) have been proposed for use as symbol synchronizers in digital communication receivers. [Communication- receiver subsystems that can perform their assigned functions in the absence of synchronization with the phases of their carrier signals (“carrier synchronization”) are denoted by the term “noncoherent,” while receiver subsystems that cannot function without carrier synchronization are said to be “coherent.”] The proposal applies, more specifically, to receivers of binary phaseshift- keying (BPSK) signals generated by directly phase-modulating binary nonreturn- to-zero (NRZ) data streams onto carrier signals having known frequencies but unknown phases. The proposed noncoherent DTTLs would be modified versions of traditional DTTLs, which are coherent.

Posted in: Briefs, Electronics & Computers

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CHEM-Based Self-Deploying Planetary Storage Tanks

A document proposes self-deploying storage tanks, based on the cold elastic hibernated memory (CHEM) concept, to be used on remote planets. The CHEM concept, described in previous NASA Tech Briefs articles, involves the use of open-cell shape-memory-polymer (SMP) foam sandwich structures to make lightweight, space-deployable structures that can be compressed for storage and can later be expanded, then rigidified for use.

Posted in: Briefs, TSP, Materials

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