Briefs: Physical Sciences
Compact Instruments Measure Helium-Leak Rates
Compact, lightweight instruments have been developed for measuring small flows of helium and/or detecting helium leaks in solenoid valves when the valves are nominally closed. These instruments do not impede the flows when the valves are nominally open. They can be integrated into newly fabricated...
Briefs: Physical Sciences
Improved Measurement of Coherence in Presence of Instrument Noise

A method for correcting measured coherence spectra for the effect of incoherent instrument noise has been developed and demonstrated. Coherence measurements are widely used in engineering and science to determine the extent to which two signals are alike. The signals may come from...

A pseudo-Brewster- angle infrared radiometer has been proposed for use in noncontact measurement of the surface temperature of a large body of water (e.g., a lake or ocean). This radiometer could...

Briefs: Software
Software for Replicating Data Between X.500 and LDAP Directories

X500/LDAP Directory Replication Utility is a computer program for replicating information between X.500 and LDAP directories. [X.500 is an international standard for on-line directory services. LDAP (Lightweight Directory Access Protocol) is a simple directory access protocol.] The...

Briefs: Software
LabVIEW Serial Driver Software for an Electronic Load

A LabVIEW-language computer program enables monitoring and control of a Transistor Devices, Inc., Dynaload WCL232 (or equivalent) electronic load via an RS- 232 serial communication link between the electronic load and a remote personal computer. (The electronic load can operate at constant...

Briefs: Software
The Technical Work Plan Tracking Tool

The Technical Work Plan Tracking Tool is a web-based application that enables interactive communication and approval of contract requirements that pertain to the administration of the Science, Engineering, Analysis, and Test (SEAT) contract at Johnson Space Center. The implementation of the application has...

Briefs: Mechanical & Fluid Systems
Using ERF Devices To Control Deployments of Space Structures

A report proposes devices containing electrorheological fluids (ERFs) damper for controlling deployments of lightweight, flexible structures in outer space. The structures would include spring members that could be wound or compressed for compact stowage during transport. The ERF based...

Two monolithic microwave integrated circuits (MMICs) have been designed and built to function together as a source of electromagnetic radiation at a frequency of 120 GHz. One of the...

A voltage-controlled oscillator (VCO) that operates in the frequency range from 77.5 to 83.5 GHz has been constructed in the form of a monolithic microwave integrated circuit (MMIC) that...

Briefs: Photonics/Optics
Distributing Digital Signals to Multiple Destinations

Digital signal fanout is a very common requirement in testing, experimentation, and systems integration. Unlike radio frequency signals, high-speed digital signals cannot be simply split or "teed" off to multiple destinations. Even with a matched-impedance splitter, the resulting amplitude...

Briefs: Robotics, Automation & Control
Improved Multiple-DOF SAW Piezoelectric Motors

Surface-acoustic-wave (SAW) piezoelectric motors of a proposed type would be capable of operating in multiple degrees of freedom (DOFs) simultaneously and would be amenable to integration into...

Briefs: Robotics, Automation & Control
System for Centering a Turbofan in a Nacelle During Tests

A feedback position-control system has been developed for maintaining the concentricity of a turbofan with respect to a nacelle during acoustic and flow tests in a wind tunnel. The...

Briefs: Motion Control
Lightweight, Self-Deployable Wheels

Ultra-lightweight, self-deployable wheels made of polymer foams have been demonstrated. These wheels are an addition to the roster of cold hibernated elastic memory (CHEM) structural applications. Intended originally for use on nanorovers (very small planetary-exploration robotic vehicles), CHEM wheels could...

Briefs: Motion Control
Hopping Robot With Wheels

A small prototype mobile robot is capable of (1) hopping to move rapidly or avoid obstacles and then (2) moving relatively slowly and precisely on the ground by use of wheels in the manner of previously reported exploratory robots of the "rover" type. This robot is a descendant of a more primitive hopping robot...

Briefs: Robotics, Automation & Control
Grease-Resistant O Rings for Joints in Solid Rocket Motors

There is a continuing effort to develop improved O rings for sealing joints in solid-fuel rocket motors. Following an approach based on the lessons learned in the explosion of the space shuttle Challenger, investigators have been seeking O-ring materials that exhibit adequate resilience...

Efforts are under way to develop a special class of thin-shell curved mirrors for high-resolution imaging in visible and infrared light in a variety of terrestrial or...

A strategy for autonomous navigation of a robotic vehicle across hazardous terrain involves the use of a measure of traversability of terrain within a fuzzy-logic conceptual...

An eight-pole radial magnetic bearing has been modified into a switched-reluctance electric motor capable of operating at a speed as high as 8,000 rpm at a temperature as high as 1,000 °F...

Briefs: Mechanical & Fluid Systems
Linear Back-Drive Differentials

Linear back-drive differentials have been proposed as alternatives to conventional gear differentials for applications in which there is only limited rotational motion (e.g., oscillation). The finite nature...

Briefs: Medical
Semiselective Optoelectronic Sensors for Monitoring Microbes

Sensor systems are under development for use in real-time detection and quantitation of microbes in water without need for sampling. These systems include arrays of optical sensors; miniature, portable electronic data-acquisition circuits; and optoelectronic interfaces between the...

Briefs: Electronics & Computers
Survivable Failure Data Recorders for Spacecraft

A spacecraft may be unable to communicate critical data associated with a serious or catastrophic failure. A brief report proposes a system, somewhat like a commercial aircraft "black box," for retrieving these data. A microspacecraft attached to the prime spacecraft would continually store recent...

Briefs: Electronics & Computers
Bit-Serial Adder Based on Quantum Dots

A proposed integrated circuit based on quantum-dot cellular automata (QCA) would function as a bit-serial adder. This circuit would serve as a prototype building block for demonstrating the feasibility...

Architectures that would exploit the distinct characteristics of quantum-dot cellular automata (QCA) have been proposed for digital communication networks that connect advanced digital...

A radio receiver system that features enhanced capabilities for remote sensing by use of reflected Global Positioning System (GPS) signals has been developed. This system was...

Briefs: Mechanical & Fluid Systems
Miniature Gas-Turbine Power Generator

A proposed microelectromechanical system (MEMS) containing a closed- Brayton-cycle turbine would serve as a prototype of electric- power generators for special applications in which high energy densities are required and in which, heretofore, batteries have been used. The system would have a volume of about...

Pneumatically actuated miniature peristaltic vacuum pumps have been proposed for incorporation into advanced miniature versions of scientific instruments that depend on vacuum for...

Briefs: Manufacturing & Prototyping
A Reactive-Ion Etch for Patterning Piezoelectric Thin Film

Reactive-ion etching (RIE) under conditions described below has been found to be a suitable means for patterning piezoelectric thin films made from such materials as PbZr1-xTixO3 or BaxSr1-xTiO3. In the original...

A process for transferring an entire wafer-level micromachined silicon structure for mating with and bonding to another such structure has been devised. This process is intended...

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