Topic

Two modifications improve the performance of a circularly polarized microstrip-patch-array antenna described in U.S. Patent 5,661,994. Because the phase difference between the orthogonal sides in the original design was 135°, there was substantial cross-polarization and waste of power. One...

Direct methanol fuel cells integrated with fuel reservoirs have been proposed as power sources in applications that involve power demands up to about 50 W. A prior concept of direct methanol fuel cells as alternatives to re- chargeable batteries in such applications was reported previously in...

High-performance lithium-ion electro- chemical cells and batteries have been developed to satisfy a need for longer lifetimes and greater capacities in the power supplies of the life-support systems attached to space suits. These and similar cells and batteries could also be used on Earth to satisfy...

The Autonomous Sciencecraft Constellation (ASC) software has been developed for Techsat-21 — a group of small satellites, to be launched by the Air Force Research Laboratory in 2004, intended to demonstrate the feasibility of groups of satellites cooperating in the performance of tasks. The...

A software system that resides on a server delivers training via the Internet to users of client computers. Admin- istrators can also interact with the system via client computers. The training lessons are in the form of trivia games, which are implemented by a game-engine software subsystem that is...

Traj and Traj.CGI are computer programs for designing thermal-protection systems (TPSs) for spacecraft that must survive re-entry into planetary atmospheres. Together with a separately developed program denoted FIAT, Traj and Traj.CGI are integral parts of NASA’s Entry Vehicle Integrated...

The PDS Validation Toolkit is an integrated set of scripts and computer programs for determining whether data recorded on compact disk (CD) or digital video disk (DVD) conform to the standards of the Planetary Data System (PDS). The software provides both command- line and graphical user interfaces,...

Tempest is a computer program that functions as a HyperText Transfer Protocol (HTTP) server for embedded systems. Tempest enables remote command and control of embedded systems. Tempest accepts HTTP requests from standard Webbrowser programs running on remote client computers and returns HyperText Markup...

A Java bean that offers high performance display of images has been developed as a component of the Java Advanced Display Environment (JADE) computer program. This component works asynchronously, loading and/or computing image tiles as needed in background threads. In so doing, it enables a main...

A computer program designed for execution aboard an exploratory spacecraft analyzes scientific data (especially image data) in order to (1) enable the reservation of limited communication resources for transmission of data likely to be of significant scientific value and (2) enable...

A variable delay line is being developed as part of a far-infrared or submillimeter- wavelength interferometer that would operate in a vacuum in the cryogenic temperature range. No such delay line for spatial interferometry has previously been built for operation under these conditions.

Highly precise air bearings for suspending objects over an epoxy flat floor in a laboratory have been developed. These bearings float on airgaps 3 to 5 mil (about 0.08 to 0.13 mm) thick. They are modern versions of precise air bearings, developed during the 1960s, that offer a working coefficient of friction of only...

A report summarizes the development, applications, and procedures for use of ENSAERO, a computer program for simulating aeroelastic phenomena (e.g., wing flutter) of aircraft and spacecraft. ENSAERO computes aeroelastic responses by simultaneously numerically integrating Euler and/or Navier-Stokes equations of airflow and...

The Foveal Extra-Vehicular Activity Helper-Retriever (FEVAHR) is a mobile robot that features a hierarchical foveal machine-vision system (HFMV). The FEVAHR is a prototype of future robots that could detect, recognize, track, and pursue objects and avoid obstacles while operating autonomously, controlled by...

An airborne submillimeter-wavelength radiometer, expected to be built and tested in the near future, is designed primarily to yield measurement data that can be processed to quantify the ice contents and mean sizes (and, to some extent, the shapes) of ice crystals in cirrus clouds that range...

The membrane test cell (MTC) is an automated laboratory apparatus that applies a known osmotic potential across a membrane and measures the kinetics of the resulting transport of solvents across the membrane as a function of time. Data acquired by use of the MTC should prove especially...

A technique for detecting a small leak of gas into a vacuum involves the use of a diaphragm made of a thin film of poly (vinylidene fluoride) [PVDF]. To exploit the piezoelectricity of PVDF for this purpose, both sides of the film are coated with thin, electrically conductive layers that serve as...

Software that performs the functions of an FQPSK-B receiver (and to some extent, an FQPSK-B transmitter) has been developed to reduce the risks and costs associated with the development of hardware FQPSK-B transmitters and receivers. (“FQPSK-B” signifies version B of Feher Quadrature-Phase-Shift Keying,...

The Web Interactive Training (WIT) project at Kennedy Space Center has expanded its course offerings, enhanced its technical capabilities, and automated its administrative functions. Aspects of the WIT project at previous stages of development were reported in “Further Developments in Web Interactive Training”...

A paper presents some novel conclusions concerning the Shvab-Zel’dovich (SZ) vari- ables, which are linear combinations of dep- endent variables in mathematical models of multicomponent, chemically reacting flows. The SZ variables represent scalar quantities that are conserved, that is, are not...

This report discusses a proposed docking mechanism to be located in a small hangar on the outside of the International Space Station (ISS). The mechanism would enable docking of a miniature robotic spacecraft (or free flyer) that would carry a video camera and would operate in the vicinity of the ISS....

A report describes an emergency tether-deployment (ETD) system designed to minimize the harm caused by two events that can occur during deployment of tethered payloads from a space shuttle in orbit. One such event is snagging of the tether during payout while the payload is near the shuttle,...

A paper presents a study of multilayer thermal insulations for protecting spacecraft against aerodynamic heating during reentry into a planetary atmosphere. A multilayer insulation considered in the study comprised (1) thin ceramic/composite foils coated with gold for high reflectance...