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At least 955 records · Page 53

Simulator evaluation of takeoff performance monitoring system displays

The development of head-up and head-down cockpit displays to convey symbolic status and advisory information to the pilot to aid him in his decision to continue or abort takeoff is described. It also describes a pilot-in-the-loop evaluation of the displays using the NASA Langley transport systems research vehicle fixed-base simulator. It was found that the head-up display was monitored with little effort and did not obstruct or distract from the runway scene.

Middleton, David B.↗

Rotorcraft deceleration to hover using image-based guidance

Rotorcraft operating in hostile environment fly at low altitudes to minimize exposure to the defensive weapons arrayed against them. The development of intelligent guidance commands at low altitudes requires the integration of conventional guidance with the information provided by the sensor on relative position between the vehicle and local terrain or obstacles. Deceleration to hover (DTH) is one of the common maneuvers executed by a rotorcraft. The authors describe the integration of DTH guidance logic with an image-based scheme to estimate the hover point. The performance of such a system is affected by parameters of the guidance and by navigation and image processing algorithms. Results are presented on the effect of the parameters on system performance.

Sridhar, Banavar↗

An intelligent, free-flying robot

The ground based demonstration of the extensive extravehicular activity (EVA) Retriever, a voice-supervised, intelligent, free flying robot, is designed to evaluate the capability to retrieve objects (astronauts, equipment, and tools) which have accidentally separated from the Space Station. The major objective of the EVA Retriever Project is to design, develop, and evaluate an integrated robotic hardware and on-board software system which autonomously: (1) performs system activation and check-out; (2) searches for and acquires the target; (3) plans and executes a rendezvous while continuously tracking the target; (4) avoids stationary and moving obstacles; (5) reaches for and grapples the target; (6) returns to transfer the object; and (7) returns to base.

Reuter, G. J.↗

An intelligent, free-flying robot

The ground-based demonstration of EVA Retriever, a voice-supervised, intelligent, free-flying robot, is designed to evaluate the capability to retrieve objects (astronauts, equipment, and tools) which have accidentally separated from the Space Station. The major objective of the EVA Retriever Project is to design, develop, and evaluate an integrated robotic hardware and on-board software system which autonomously: (1) performs system activation and check-out, (2) searches for and acquires the target, (3) plans and executes a rendezvous while continuously tracking the target, (4) avoids stationary and moving obstacles, (5) reaches for and grapples the target, (6) returns to transfer the object, and (7) returns to base.

Reuter, G. J.↗

High performance computing system for flight simulation at NASA Langley

The computer architecture and components used in the NASA Langley Advanced Real-Time Simulation System (ARTSS) are briefly described and illustrated with diagrams and graphs. Particular attention is given to the advanced Convex C220 processing units, the UNIX-based operating system, the software interface to the fiber-optic-linked Computer Automated Measurement and Control system, configuration-management and real-time supervisor software, ARTSS hardware modifications, and the current implementation status. Simulation applications considered include the Transport Systems Research Vehicle, the Differential Maneuvering Simulator, the General Aviation Simulator, and the Visual Motion Simulator.

Cleveland, Jeff I., II↗

Control and dynamics of an anti-friction levitation system

A novel anti-friction levitator concept has been devised and analytically evaluated to overcome support bearing friction and thereby minimize the structural damping of the Large Spacecraft Control Laboratory (LSCL) experiment structure at JPL. A dynamic model and controller design have been developed for the new levitation system. Simulation results show excellent system performance even when the system is subjected to significant measurement noise and hardware saturation effects.

Ih, C.-H. C.↗

Microbiological concerns and methodological approaches related to bacterial water quality in spaceflight

A number of microbiological issues are of critical importance to crew health and system performance in spacecraft water systems. This presentation reviews an army of these concerns which include factors that influence water treatment and disinfection in spaceflight such as biofilm formation and the physiological responses of bacteria in clean water systems. Factors associated with spaceflight like aerosol formation under conditions of microgravity are also discussed within the context of airborne infections such as Legionellosis. Finally, a spectrum of analytical approaches is reviewed to provide an evaluation of methodological alternatives that have been suggested or used to detect microorganisms of interest in water systems. These range from classical approaches employing colony formation on specific microbiological growth media to direct (i.e. microscopic) and indirect (e.g. electrochemical) methods as well as the use of molecular approaches and gene probes. These techniques are critically evaluated for their potential utility in determining microbiological water quality through the detection of microorganisms under the influence of ambient environmental stress inherent in spaceflight water systems.

Pyle, Barry H.↗

Computational Intelligence and Its Impact on Future High-Performance Engineering Systems

This document contains presentations from the joint UVA/NASA Workshop on Computational Intelligence held at the Virginia Consortium of Engineering and Science Universities, Hampton, Virginia, June 27-28, 1995. The presentations addressed activities in the areas of fuzzy logic, neural networks, and evolutionary computations. Workshop attendees represented NASA, the National Science Foundation, the Department of Energy, National Institute of Standards and Technology (NIST), the Jet Propulsion Laboratory, industry, and academia. The workshop objectives were to assess the state of technology in the Computational intelligence area and to provide guidelines for future research.

Noor, Ahmed K.↗

Evaluation of the Hydrodynamic Focusing Bioreactor (HDFB) and the Centrifugal Absorption Cartridge System (CACS) Performance Under Micro G

The Hydrodynamic Focusing Bioreactor (HDFB) technology is designed to provide a flow field with nearly uniform shear force throughout the vessel, which can provide the desired low shear force spatial environment to suspend three-dimensional cell aggregates while providing optimum mass transfer. The reactor vessel consists of a dome-shaped cell culture vessel, a viscous spinner, an access port, and a rotating base. The domed vessel face has a radius of R(o). and rotates at 0mega(o) rpm, while the internal viscous spinner has a radius of R(i) and rotates at 0mega(i) rpm. The culture vessel is completely filled with cell culture medium into which three-dimensional cellular structures are introduced. The HDFB domed vessel and spinner were driven by two independent step motors,

Gonda, Steve↗

Mass Storage Performance Information System

The purpose of this task is to develop a data warehouse to enable system administrators and their managers to gather information by querying the data logs of the MDSDS. Currently detailed logs capture the activity of the MDSDS internal to the different systems. The elements to be included in the data warehouse are requirements analysis, data cleansing, database design, database population, hardware/software acquisition, data transformation, query and report generation, and data mining.

Scheuermann, Peter↗

EVA Physiology, Systems and Performance [EPSP] Project

This viewgraph presentation gives a general overview of the biomedical and technological challenges of Extravehicular Activity (EVA). The topics covered include: 1) Prebreathe Protocols; 2) Lunar Suit Testing and Development; and 3) Lunar Electric Rover and Exploration Operations Concepts.

Gernhardt, Michael L.↗

Error Modeling of Multibaseline Optical Truss: Part 1: Modeling of System Level Performance

Global astrometry is the measurement of stellar positions and motions. These are typically characterized by five parameters, including two position parameters, two proper motion parameters, and parallax. The Space Interferometry Mission (SIM) will derive these parameters for a grid of approximately 1300 stars covering the celestial sphere to an accuracy of approximately 4uas, representing a two orders of magnitude improvement over the most precise current star catalogues. Narrow angle astrometry will be performed to a 1uas accuracy. A wealth of scientific information will be obtained from these accurate measurements encompassing many aspects of both galactic (and extragalactic science. SIM will be subject to a number of instrument errors that can potentially degrade performance. Many of these errors are systematic in that they are relatively static and repeatable with respect to the time frame and direction of the observation. This paper and its companion define the modeling of the, contributing factors to these errors and the analysis of how they impact SIM's ability to perform astrometric science.

meterology modeling↗

Plant Atrium System for Food Production in NASA's Deep Space Habitat Tests

Future human space exploration missions will need functional habitat systems. Possible concepts are assessed for integration issues, power requirements, crew operations, technology, and system performance. A food production system concept was analyzed at NASA Desert Research and Technology Studies (DRATS) in 2011, and at NASA JSC in 2012. System utilizes fresh foods (vegetables and small fruits) which are harvested on a continuous basis. Designed to improve crew's diet and quality of life without interfering with other components or operations.

Massa, Gioia D.↗