Keyword: Spacecraft

Briefs: Mechanical & Fluid Systems

A proposed family of devices for inducing fatigue in bolts in order to break the bolts would incorporate piezoelectric actuators into resonant fixtures as in ultrasonic/ sonic...

Briefs: Software
Generic Spacecraft Model for Real-Time Simulation

"Generic Spacecraft" is the name of an evolving library of software that provides for simulation of a generic spacecraft that can orbit the Earth and land on the Moon (and, eventually, on Mars). This library is incorporated into the Langley Standard Realtime Simulation in C++ (LaSRS++) software...

Application Briefs: Sensors/Data Acquisition
Remote Voltage Sensor
Quasar Federal Systems
San Diego, CA

Electrostatic charges impact the...

Application Briefs: Sensors/Data Acquisition
RTAX-S field-programmable gate arrays (FPGAs) Actel
Mountain View, CA

Actel’s RTAX-S field-programmable gate arrays...

Briefs: Information Technology
Algorithm Optimally Orders Forward-Chaining Inference Rules

People typically develop knowledge bases in a somewhat ad hoc manner by incrementally adding rules with no specific organization. This often results in a very inefficient execution of those rules since they are so often order sensitive. This is relevant to tasks like Deep Space Network...

Briefs: Electronics & Computers

A proposed microstrip Yagi antenna would operate at a frequency of 8.4 GHz (which is in the X band) and would feature a mechanically simpler, more elegant design, relative to a prior...

Briefs: Photonics/Optics
Optical Displacement Sensor for Sub-Hertz Applications

A document discusses a sensor made from off-the-shelf electro-optical photo-diodes and electronics that achieves 20 nm/(Hz)1/2 displacement sensitivity at 1 mHz. This innovation was created using a fiber-coupled laser diode (or Nd:YAG) through a collimator and an aperture as the...

Briefs: Materials
Foam Core Shielding for Spacecraft

A foam core shield (FCS) system is now being developed to supplant multilayer insulation (MLI) systems heretofore installed on spacecraft for thermal management and protection against meteoroid impacts. A typical FCS system consists of a core sandwiched between a face sheet and a back sheet. The core can...

Briefs: Information Technology
Implementation of a Point Algorithm for Real-Time Convex Optimization

The primal-dual interior-point algorithm implemented in G-OPT is a relatively new and efficient way of solving convex optimization problems. Given a prescribed level of accuracy, the convergence to the optimal solution is guaranteed in a predetermined, finite number of...

Briefs: Manufacturing & Prototyping
Creep Forming of Carbon-Reinforced Ceramic-Matrix Composites

A set of lecture slides describes an investigation of creep forming as a means of imparting desired curvatures to initially flat stock plates of carbon-reinforced ceramic-matrix composite (C-CMC) materials. The investigation is apparently part of a continuing effort to develop improved...

Application Briefs: Electronics & Computers
VXS-based satellite communications development system
TEK Microsystems
Chelmsford, MA

TEK Microsystems’ first VXS-based...

Application Briefs: Sensors/Data Acquisition
Endevco Corp.
San Juan Capistrano, CA

On August 8, 2007, three Space Shuttle Main Engines (SSMEs) from Pratt &...

Briefs: Physical Sciences

The High Altitude/ Re-Entry Vehicle Infrared Imaging (HARVII) system is a portable instrumentation system for tracking and thermal imaging of a possibly distant and moving object. The HARVII...

Briefs: Electronics & Computers
VCO PLL Frequency Synthesizers for Spacecraft Transponders

Two documents discuss a breadboard version of advanced transponders that, when fully developed, would be installed on future spacecraft to fly in deep space. These transponders will be required to be capable of operation on any deepspace-communications uplink frequency channel between...

Briefs: Electronics & Computers
Wide Tuning Capability for Spacecraft Transponders

A document presents additional information on the means of implementing a capability for wide tuning of microwave receiver and transmitter frequencies in the development reported in the immediately preceding article, "VCO PLL Frequency Synthesizers for Spacecraft Transponders" (NPO-42909). The...

Briefs: Mechanical & Fluid Systems
Adaptive Deadband Synchronization for a Spacecraft Formation

A paper discusses general problems in estimation and control of the states (positions, attitudes, and velocities) of spacecraft flying in formation, then addresses the particular formation-flying-control problem of synchronization of deadbands. The paper presents a...

Briefs: Information Technology
Estimating the Inertia Matrix of a Spacecraft

A paper presents a method of utilizing some flight data, aboard a spacecraft that includes reaction wheels for attitude control, to estimate the inertia matrix of the spacecraft. The required data are digitized samples of (1) the spacecraft attitude in an inertial reference frame as measured, for...

Briefs: Mechanical & Fluid Systems
Increasing the Life of a Xenon-Ion Spacecraft Thruster

A short document summarizes the redesign of a xenon-ion spacecraft thruster to increase its operational lifetime beyond a limit heretofore imposed by nonuniform ion-impact erosion of an accelerator electrode grid. A peak in the ion current density on the centerline of the thruster causes...

Who's Who: Aerospace

The Inductive Monitoring System (IMS) is a new computer program that monitors gyroscopes that keep the International Space Station properly oriented in space....

Application Briefs: Physical Sciences
DynaJets® and DynaSwirl® cavitating jet technologies
Jessup, MD

Water is a critical product of...

Application Briefs: Physical Sciences
QE65000 spectrometer
Ocean Optics
Dunedin, FL

Scheduled to launch from NASA’s Kennedy Space Center (KSC) in Florida...

Briefs: Information Technology
Autogen Version 2.0

Version 2.0 of the autogen software has been released. "Autogen" (automated sequence generation) signifies both a process and software used to implement the process of automated generation of sequences of commands in a standard format for uplink to spacecraft. Autogen requires fewer workers than are needed for older manual...

Briefs: Information Technology
NASA Enterprise Visual Analysis

NASA Enterprise Visual Analysis (NEVA) is a computer program undergoing development as a successor to Launch Services Analysis Tool (LSAT), formerly known as Payload Carrier Analysis Tool (PCAT). NEVA facilitates analyses of proposed configurations of payloads and packing fixtures (e.g. pallets) in a space shuttle...

Briefs: Information Technology

The descent image motion estimation system (DIMES) is a system of hardware and software, designed for original use in estimating the horizontal velocity of a spacecraft descending...

Articles: RF & Microwave Electronics

Software techniques for use in the global positioning system (GPS)1,2 have recently captured the growing interest of communication and navigation...

Briefs: Mechanical & Fluid Systems
Capacitors Would Help Protect Against Hypervelocity Impacts

A proposal investigates alternatives to the present "bumper" method of protecting spacecraft against impacts of meteoroids and orbital debris. The proposed method is based on a British highvoltage- capacitance technique for protecting armored vehicles against shapedcharge warheads.

Briefs: Medical
Ultraviolet-Resistant Bacterial Spores

A document summarizes a study in which it was found that spores of the SAFR-032 strain of Bacillus pumilus can survive doses of ultraviolet (UV) radiation, γ radiation, and hydrogen peroxide in proportions much greater than those of other bacteria. The study was part of a continuing effort to understand...

Briefs: Physical Sciences
Telescope Formation at L2 for Observing Earth’s Atmosphere

Two documents describe a proposed Earth-atmosphere observatory to orbit the Sun at the Sun-Earth L2 Lagrange point — a point of unstable equilibrium in the shadow of the Earth, about 1.5 million km from the Earth along an outward projection of the Earth-Sun axis. The observatory...

Briefs: Physical Sciences
Photometric Calibration of Consumer Video Cameras

Equipment and techniques have been developed to implement a method of photometric calibration of consumer video cameras for imaging of objects that are sufficiently narrow or sufficiently distant to be optically equivalent to point or line sources. Heretofore, it has been difficult to calibrate...