Electronics & Software

A digital phase meter has been designed to satisfy stringent requirements for measuring differences between phases of radiofrequency (RF) subcarrier signals modulated onto laser beams involved in the operation of a planned space-borne gravitational- wave-detecting heterodyne laser...

Use of multiple-antenna radar systems aboard moving high-altitude platforms has been proposed for measuring rainfall. The platforms contemplated in the proposal would be primarily spacecraft, but, in principle, the proposal could also apply to aircraft. The problem of measuring rainfall...

A document discusses the physical and engineering principles affecting the design of the Smart Data Node in the Sky (SDNITS) — a proposed Earthorbiting satellite for relaying scientific data from other Earth-orbiting satellites to one or more ground station(s). The basic concept of the SDNITS is similar to that of...

Surfer is an extensible framework for selecting and ranking grid resources. A resource is defined as anything that needs selecting such as compute resources, storage resources, and data resources. The user specifies the set of resource types desired, the constraints that must hold over all the resources, and the...

InvestigationOrganizer (IO) is a Webbased collaborative information system that integrates the generic functionality of a database, a document repository, a semantic hypermedia browser, and a rulebased inference system with specialized modeling and visualization functionality to support accident/mishap...

A control architecture and algorithms to implement the architecture have been conceived to enable a robot to learn from its experiences and to combine knowledge gained from prior experiences in such a way as to be able to solve new problems. The architecture is an abstraction of an...

The Hypothetical Scenario Generator for Fault-tolerant Diagnostics (HSG) is an algorithm being developed in conjunction with other components of artificial- intelligence systems for automated diagnosis and prognosis of faults in spacecraft, aircraft, and other complex engineering systems....

A model predictive control (MPC) algorithm that differs from prior MPC algorithms has been developed for controlling an uncertain nonlinear system. This algorithm guarantees the resolvability of an associated finite-horizon optimal-control problem in a receding horizon implementation. Given...

A versatile computer program analyzes the link-design control table necessary for designing the telecommunication subsystem of a spacecraft in orbit around the Earth or on a deep-space mission. The program helps to calculate all the important parameter values for spacecraft-to-ground telemetry links...

A computer program implements a finite-element-based method of predicting the deformations of thin aerospace structures made of isotropic materials or anisotropic fiber-reinforced composite materials. The technique and corresponding software are applicable to thin shell structures in...

LMBTRK is a computer program that is used together with two software libraries known as ERHAND and HYBRRD to generate spacecraft-pointing vectors for limb-tracking maneuvers needed for experiments on propagation of radio signals through planetary atmospheres. LMBTRK determines, as a function...

The Enhanced Master Controller Unit Tester (EMUT) software is a tool for development and testing of software for a master controller (MC) flight computer. The primary function of the EMUT software is to simulate interfaces between the MC computer and external analog and digital circuitry (including other...

Rover Graphical Simulator (RGS) is a package of software that generates images of the motion of a wheeled robotic exploratory vehicle (rover) across terrain that includes obstacles and regions of varying traversability. The simulated rover moves autonomously, utilizing reasoning and decision-making capabilities of a...

A document discusses a silicon-oninsulator (SOI) complementary metal oxide/ semiconductor (CMOS) integrated- circuit operational amplifier to be replicated and incorporated into sensor and actuator systems of Mars- explorer robots. This amplifier is designed to function at a supply potential...