Special Coverage

Transducer-Actuator Systems for On-Machine Measurements and Automatic Part Alignment
Wide-Area Surveillance Using HD LWIR Uncooled Sensors
Heavy Lift Wing in Ground (WIG) Cargo Flying Boat
Technique Provides Security for Multi-Robot Systems
Bringing New Vision to Laser Material Processing Systems
NASA Tests Lasers’ Ability to Transmit Data from Space
Converting from Hydraulic Cylinders to Electric Actuators
Automating Optimization and Design Tasks Across Disciplines
Vibration Tables Shake Up Aerospace and Car Testing
Supercomputer Cooling System Uses Refrigerant to Replace Water

MMIC Amplifiers and Wafer Probes for 350 to 500 GHz

Amplifiers like these are needed for submillimeter-wavelength imagers and scientific instruments.

Several different experimental monolithic microwave integrated circuit (MMIC) amplifiers have been designed to operate in frequency bands ranging from 350 to 500 GHz and were undergoing fabrication at the time of reporting the information for this article. Probes for on-wafer measurement of electrical parameters [principally, the standard scattering parameters (“S” parameters)] of these amplifiers have been built and tested as essential components of systems to be used in quantifying the performances of the amplifiers. These accomplishments are intermediate products of a continuing effort to develop solid-state electronic amplifiers capable of producing gain at ever-higher frequencies, now envisioned to range up to 800 GHz. Such amplifiers are needed for further development of compact, portable imaging systems and scientific instruments for a variety of potential applications that include detection of hidden weapons, measuring winds, and measuring atmospheric concentrations of certain molecular species.

Posted in: Briefs, TSP, Electronics & Computers, Amplifiers, Integrated circuits, Amplifiers, Integrated circuits

Public Risk Assessment Program

The Public Entry Risk Assessment (PERA) program addresses risk to the public from shuttle or other spacecraft re-entry trajectories. Managing public risk to acceptable levels is a major component of safe spacecraft operation. PERA is given scenario inputs of vehicle trajectory, probability of failure along that trajectory, the resulting debris characteristics, and field size and distribution, and returns risk metrics that quantify the individual and collective risk posed by that scenario. Due to the large volume of data required to perform such a risk analysis, PERA was designed to streamline the analysis process by using innovative mathematical analysis of the risk assessment equations. Real-time analysis in the event of a shuttle contingency operation, such as damage to the Orbiter, is possible because PERA allows for a change to the probability of failure models, therefore providing a much quicker estimation of public risk.

Posted in: Briefs, TSP, Software, Mathematical models, Computer software / hardware, Computer software and hardware, Computer software / hardware, Computer software and hardware, Risk assessments, Entry, descent, and landing, Spacecraft

Particle Swarm Optimization Toolbox

The Particle Swarm Optimization Toolbox is a library of evolutionary optimization tools developed in the MAT-LAB environment. The algorithms contained in the library include a genetic algorithm (GA), a single-objective particle swarm optimizer (SOPSO), and a multi-objective particle swarm optimizer (MOPSO). Development focused on both the SOPSO and MOPSO. A GA was included mainly for comparison purposes, and the particle swarm optimizers appeared to perform better for a wide variety of optimization problems. All algorithms are capable of performing unconstrained and constrained optimization. The particle swarm optimizers are capable of performing single and multi-objective optimization. The SOPSO and MOPSO algorithms are based on swarming theory and bird-flocking patterns to search the trade space for the optimal solution or optimal trade in competing objectives. The MOPSO generates Pareto fronts for objectives that are in competition.

Posted in: Briefs, TSP, Software, CAD / CAM / CAE, CAD, CAM, and CAE, Mathematical models, Optimization

Telescience Support Center Data System Software

The Telescience Support Center (TSC) team has developed a database-driven, increment-specific Data Requirement Document (DRD) generation tool that automates much of the work required for generating and formatting the DRD. It creates a database to load the required changes to configure the TSC data system, thus eliminating a substantial amount of labor in database entry and formatting.

Posted in: Briefs, TSP, Software, Artificial intelligence, Computer software / hardware, Computer software and hardware, Artificial intelligence, Computer software / hardware, Computer software and hardware, Data management

Update on PISCES

An updated version of the Platform Independent Software Components for the Exploration of Space (PISCES) software library is available. A previous version was reported in “Library for Developing Spacecraft-Mission-Planning Software” (MSC-22983), NASA Tech Briefs, Vol. 25, No. 7 (July 2001), page 52. To recapitulate: This software provides for Web-based, collaborative development of computer programs for planning trajectories and trajectory-related aspects of spacecraft-mission design. The library was built using state-of-the-art object-oriented concepts and software-development methodologies. The components of PISCES include Java-language application programs arranged in a hierarchy of classes that facilitates the reuse of the components.

Posted in: Briefs, Software, Trajectory control, Computer software / hardware, Computer software and hardware, Internet, Spacecraft guidance, Computer software / hardware, Computer software and hardware, Internet, Spacecraft guidance

Ground and Space Radar Volume Matching and Comparison Software

This software enables easy comparison of ground- and space-based radar observations. The software was initially designed to compare ground radar reflectivity from operational, ground based S- and C-band meteorological radars with comparable measurements from the Tropical Rainfall Measuring Mission (TRMM) satellite’s Precipitation Radar (PR) instrument. The software is also applicable to other ground-based and space-based radars. The ground and space radar volume matching and comparison software was developed in response to requirements defined by the Ground Validation System (GVS) of Goddard’s Global Precipitation Mission (GPM) project.

Posted in: Briefs, TSP, Software, Calibration, Computer software / hardware, Computer software and hardware, Radar, Computer software / hardware, Computer software and hardware, Radar, Weather and climate, Satellites

Web-Based Interface for Command and Control of Network Sensors

This software allows for the visualization and control of a network of sensors through a Web browser interface. It is currently being deployed for a network of sensors monitoring Mt. Saint Helen’s volcano; however, this innovation is generic enough that it can be deployed for any type of sensor Web. From this interface, the user is able to fully control and monitor the sensor Web. This includes, but is not limited to, sending “test” commands to individual sensors in the network, monitoring for real-world events, and reacting to those events.

Posted in: Briefs, Software, Architecture, Computer software / hardware, Computer software and hardware, Internet, Sensors and actuators, Architecture, Computer software / hardware, Computer software and hardware, Internet, Sensors and actuators

Orbit Determination Toolbox

The Orbit Determination Toolbox is an orbit determination (OD) analysis tool based on MATLAB and Java that provides a flexible way to do early mission analysis. The toolbox is primarily intended for advanced mission analysis such as might be performed in concept exploration, proposal, early design phase, or rapid design center environments. The emphasis is on flexibility, but it has enough fidelity to produce credible results. Insight into all flight dynamics source code is provided.

Posted in: Briefs, Software, Trajectory control, CAD / CAM / CAE, CAD, CAM, and CAE, Spacecraft guidance, Spacecraft guidance, Aircraft operations

Distributed Observer Network

The Distributed Observer network (DON) is a NASA-collaborative environment that leverages game technology to bring three-dimensional simulations to conventional desktop and laptop computers in order to allow teams of engi-
neers working on design and operations, either individually or in groups, to view and collaborate on 3D representations of data generated by authoritative tools such as Delmia Envision, Pro/Engineer, or Maya. The DON takes models and telemetry from these sources and, using commercial game engine technology, displays the simulation results in a 3D visual environment.

Posted in: Briefs, Software, Computer simulation, Displays, Displays, Collaboration and partnering, Systems engineering

Computer-Automated Evolution of Spacecraft X-Band Antennas

A document discusses the use of computer-aided evolution in arriving at a design for X-band communication antennas for NASA’s three Space Technology 5 (ST5) satellites, which were launched on March 22, 2006. Two evolutionary algorithms, incorporating different representations of the antenna design and different fitness functions, were used to automatically design and optimize an X-band antenna design. A set of antenna designs satisfying initial ST5 mission requirements was evolved by use these algorithms.

Posted in: Briefs, TSP, Software, CAD / CAM / CAE, CAD, CAM, and CAE, Mathematical models, Antennas, Antennas, Spacecraft

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