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At least 1,117 records · Page 62
All sourcesNASA NTRSDOE OSTI
NASA NTRS2002

NASA Smart Surgical Probe Project

Information Technologies being developed by NASA to assist astronaut-physician in responding to medical emergencies during long space flights are being employed for the improvement of women's health in the form of "smart surgical probe". This technology, initially developed for neurosurgery applications, not only has enormous potential for the diagnosis and treatment of breast cancer, but broad applicability to a wide range of medical challenges. For the breast cancer application, the smart surgical probe is being designed to "see" a suspicious lump, determine by its features if it is cancerous, and ultimately predict how the disease may progress. A revolutionary early breast cancer detection tool based on this technology has been developed by a commercial company and is being tested in human clinical trials at the University of California at Davis, School of Medicine. The smart surgical probe technology makes use of adaptive intelligent software (hybrid neural networks/fuzzy logic algorithms) with the most advanced physiologic sensors to provide real-time in vivo tissue characterization for the detection, diagnosis and treatment of tumors, including determination of tumor microenvironment and evaluation of tumor margins. The software solutions and tools from these medical applications will lead to the development of better real-time minimally-invasive smart surgical probes for emergency medical care and treatment of astronauts on long space flights.

Mah, Robert W.↗
NASA NTRS1989

Laboratory test methodology for evaluating the effects of electromagnetic disturbances on fault-tolerant control systems

Control systems for advanced aircraft, especially those with relaxed static stability, will be critical to flight and will, therefore, have very high reliability specifications which must be met for adverse as well as nominal operating conditions. Adverse conditions can result from electromagnetic disturbances caused by lightning, high energy radio frequency transmitters, and nuclear electromagnetic pulses. Tools and techniques must be developed to verify the integrity of the control system in adverse operating conditions. The most difficult and illusive perturbations to computer based control systems caused by an electromagnetic environment (EME) are functional error modes that involve no component damage. These error modes are collectively known as upset, can occur simultaneously in all of the channels of a redundant control system, and are software dependent. A methodology is presented for performing upset tests on a multichannel control system and considerations are discussed for the design of upset tests to be conducted in the lab on fault tolerant control systems operating in a closed loop with a simulated plant.

Belcastro, Celeste M.↗
NASA NTRS1999

Piloted Simulation Investigation of a Supersonic Transport Configuration (LaRC.4)

This report contains a description of the test facilities and software utilized during a joint NASA/aerospace industry study of improved control laws and desired inceptor characteristics for a candidate supersonic transport air-craft design. Details concerning the characteristics of the simulation cockpit, image generator and display systems, and motion platform are described. Depictions of the various display formats are included. The test schedule, session log, and flight cards describing the maneuvers performed is included. A brief summary of high-lights of the study is given. Modifications made to the industry-provided simulation model are described. This report is intended to serve as a reference document for industry researchers.

Jackson, E. Bruce↗
NASA NTRS2002

Utilization of Internet Protocol-Based Voice Systems in Remote Payload Operations

Due to limited crew availability to support science and the large number of experiments to be operated simultaneously, telescience is key to a successful International Space Station (ISS) science program. Crew, operations personnel at NASA centers, and researchers at universities and companies around the world must work closely together to per orm scientific experiments on-board ISS. The deployment of reliable high-speed Internet Protocol (IP)-based networks promises to greatly enhance telescience capabilities. These networks are now being used to cost-effectively extend the reach of remote mission support systems. They reduce the need for dedicated leased lines and travel while improving distributed workgroup collaboration capabilities. NASA has initiated use of Voice over Internet Protocol (VoIP) to supplement the existing mission voice communications system used by researchers at their remote sites. The Internet Voice Distribution System (IVoDS) connects remote researchers to mission support "loopsll or conferences via NASA networks and Internet 2. Researchers use NODS software on personal computers to talk with operations personnel at NASA centers. IVoDS also has the ;capability, if authorized, to allow researchers to communicate with the ISS crew during experiment operations. NODS was developed by Marshall Space Flight Center with contractors & Technology, First Virtual Communications, Lockheed-Martin, and VoIP Group. NODS is currently undergoing field-testing with full deployment for up to 50 simultaneous users expected in 2002. Research is being performed in parallel with IVoDS deployment for a next-generation system to qualitatively enhance communications among ISS operations personnel. In addition to the current voice capability, video and data/application-sharing capabilities are being investigated. IVoDS technology is also being considered for mission support systems for programs such as Space Launch Initiative and Homeland Defense.

Chamberlain, jim↗
NASA NTRSDate not supplied

Resilient Autonomy in the Face of Adversity

The NASA Resilient Autonomy Project developed a software framework that implemented a Run Time Assurance (RTA) architecture that leveraged ASTM International’s F3269 Industry Standard for safely bounding complex behavior in aircraft. This framework was called the Expandable Variable Autonomy Architecture, or EVAA. EVAA was developed during the height of the Covid-19 lockdown that caused the Resilient Autonomy team to pivot from flight test to distributed simulator testing. EVAA was developed to be platform and mission agnostic where platform specifics were behind a hardware abstraction layer that EVAA called a Coupler. EVAA was able to host multiple safety monitors that could resolve individual safety hazards. EVAA was able to resolve priority conflicts when multiple safety hazards needed to be resolved simultaneously and was able to resolve highly complex situations in a safe manner that could exceed human capabilities.

Ethan Williams↗
NASA NTRS2014

Network Monitor and Control of Disruption-Tolerant Networks

For nearly a decade, NASA and many researchers in the international community have been developing Internet-like protocols that allow for automated network operations in networks where the individual links between nodes are only sporadically connected. A family of Disruption-Tolerant Networking (DTN) protocols has been developed, and many are reaching CCSDS Blue Book status. A NASA version of DTN known as the Interplanetary Overlay Network (ION) has been flight-tested on the EPOXI spacecraft and ION is currently being tested on the International Space Station. Experience has shown that in order for a DTN service-provider to set up a large scale multi-node network, a number of network monitor and control technologies need to be fielded as well as the basic DTN protocols. The NASA DTN program is developing a standardized means of querying a DTN node to ascertain its operational status, known as the DTN Management Protocol (DTNMP), and the program has developed some prototypes of DTNMP software. While DTNMP is a necessary component, it is not sufficient to accomplish Network Monitor and Control of a DTN network. JPL is developing a suite of tools that provide for network visualization, performance monitoring and ION node control software. This suite of network monitor and control tools complements the GSFC and APL-developed DTN MP software, and the combined package can form the basis for flight operations using DTN.

network monitor↗
NASA NTRS1995

SeaWiFS calibration and algorithm validation

A substantial amount of field research has been completed during this period (1 October 1994 - 31 October 1995). The applicability of different in-flight calibration methods was studied. In addition, various field instruments and new equipment were tested to appraise their usefulness during such calibration activities. The purposes and (expected) results of these field experiments are detailed in separate sections of this report. One section contains a synopsis of calibrations conducted over both land and water targets. A second section contains the results of an experiment conducted to determine the spatial uniformity of surface reflectance at Lake Tahoe, the chosen water calibration site. Advances were also made in the area of radiative transfer software development. An existing exact radiative transfer code, Successive Orders (SO), was modified to provide outputs of the radiance distribution at arbitrary altitudes above a selected calibration target. These modifications were needed to utilize the SO software in radiance-based sensor calibrations. Serious thought was given to the general applicability of various calibration techniques to calibrations conducted over water surfaces. In particular, the practicality of the radiance-based and reflectance-based methods of in-flight radiometric calibration was evaluated.

Parada, Robert J., Jr.↗
NASA NTRSDate not supplied

NASA’s Space Launch System: Artemis I Results and the Path Forward

On Nov. 16, 2022, NASA launched the Artemis I mission on the agency’s new SLS (Space Launch System) rocket. The debut launch of the integrated vehicle sent an uncrewed Orion spacecraft into a distant retrograde (DRO) orbit about the Moon to accomplish multiple mission objectives, including evaluating Orion’s heatshield at lunar return velocities and collecting critical data from the first flight of the new superheavy lift launch vehicle. Post-flight data analyses show that the rocket performed with a high degree of precision and accuracy. In addition to completing testing and launch of the Artemis I SLS in 2022, notable progress was made on hardware for future launch vehicles that will support Artemis missions II, III, IV, and V. The Artemis II core stage is mostly complete, and its RS-25 engines were integrated in the fall of 2023. The Artemis II solid rocket booster motor segments were shipped to the launch site in September 2023. Propellant tanks are being manufactured for additional missions, solid booster segments are being cast and prepared, software is being developed, and production of new RS-25 engines is underway. A more capable upper stage is in development, as well as a large adapter to encapsulate a 10-metric ton (t) co-manifested payload. This paper will provide details on the Artemis I flight as well as cover hardware progress for the future flights as available.

John Honeycutt↗
NASA NTRS1981

Command system output bit verification

An automatic test was developed to test the ability of the deep space station (DSS) command subsystem and exciter to generate and radiate, from the exciter, the correct idle bit sequence for a given flight project or to store and radiate received command data elements and files without alteration. This test, called the command system output bit verification test, is an extension of the command system performance test (SPT) and can be selected as an SPT option. The test compares the bit stream radiated from the DSS exciter with reference sequences generated by the SPT software program. The command subsystem and exciter are verified when the bit stream and reference sequences are identical. It is a key element of the acceptance testing conducted on the command processor assembly (CPA) operational program (DMC-0584-OP-G) prior to its transfer from development to operations.

Odd, C. W.↗
NASA NTRS1990

Propulsion system-flight control integration and optimization: Flight evaluation and technology transition

Integration of propulsion and flight control systems and their optimization offers significant performance improvements. Research programs were conducted which have developed new propulsion and flight control integration concepts, implemented designs on high-performance airplanes, demonstrated these designs in flight, and measured the performance improvements. These programs, first on the YF-12 airplane, and later on the F-15, demonstrated increased thrust, reduced fuel consumption, increased engine life, and improved airplane performance; with improvements in the 5 to 10 percent range achieved with integration and with no changes to hardware. The design, software and hardware developments, and testing requirements were shown to be practical.

Burcham, Frank W., Jr.↗
NASA NTRS1994

Electric power system test and verification program

Space Station Freedom's (SSF's) electric power system (EPS) hardware and software verification is performed at all levels of integration, from components to assembly and system level tests. Careful planning is essential to ensure the EPS is tested properly on the ground prior to launch. The results of the test performed on breadboard model hardware and analyses completed to date have been evaluated and used to plan for design qualification and flight acceptance test phases. These results and plans indicate the verification program for SSF's 75-kW EPS would have been successful and completed in time to support the scheduled first element launch.

Rylicki, Daniel S.↗
NASA NTRS1993

R and T report: Goddard Space Flight Center

The 1993 Research and Technology Report for Goddard Space Flight Center is presented. Research covered areas such as (1) flight projects; (2) space sciences including cosmology, high energy, stars and galaxies, and the solar system; (3) earth sciences including process modeling, hydrology/cryology, atmospheres, biosphere, and solid earth; (4) networks, planning, and information systems including support for mission operations, data distribution, advanced software and systems engineering, and planning/scheduling; and (5) engineering and materials including spacecraft systems, material and testing, optics and photonics and robotics.

Soffen, Gerald A.↗
NASA NTRS1998

Comparison of Human Modeling Tools for Efficiency of Prediction of EVA Tasks

Design of ExtraVehicular Activity (EVA) interfaces for International Space Station is important to successful assembly. This is highlighted by the recent rise in the estimate of time required for EVA during the assembly to 900 hours. The traditional method of evaluating EVA design is examination of mockups in neutral buoyancy testing. While effective, this is costly. Any tools for streamlining this process have positive cost and schedule implications for Station design. The human modelling software package Jack has been shown to be a useful tool in computer-aided design of space hardware requiring actuation in EVA. The package has been used to aid in the design of flight hardware for a Station Assembly Mission; evaluation was based on comparison of the computer simulations with neutral buoyancy simulations. When used to predict the feasibility of tasks, the software was found to be effective for reach and visibility evaluation. Some limitations have been encountered in prediction of work clearances. Another human simulator is currently being evaluated using the same hardware and comparisons to the same Neutral Buoyancy simulations. Preliminary results for ERGO, which is derived from robotics software, indicate similar strengths and weaknesses.

Dischinger, H. Charles, Jr.↗
NASA NTRS2000

Precise Image-Based Motion Estimation for Autonomous Small Body Exploration

We have developed and tested a software algorithm that enables onboard autonomous motion estimation near small bodies using descent camera imagery and laser altimetry. Through simulation and testing, we have shown that visual feature tracking can decrease uncertainty in spacecraft motion to a level that makes landing on small, irregularly shaped, bodies feasible. Possible future work will include qualification of the algorithm as a flight experiment for the Deep Space 4/Champollion comet lander mission currently under study at the Jet Propulsion Laboratory.

Johnson, Andrew Edie↗
NASA NTRS2004

Mobile Aerial Tracking and Imaging System (MATrIS) for Aeronautical Research

A mobile, rapidly deployable ground-based system to track and image targets of aeronautical interest has been developed. Targets include reentering reusable launch vehicles as well as atmospheric and transatmospheric vehicles. The optics were designed to image targets in the visible and infrared wavelengths. To minimize acquisition cost and development time, the system uses commercially available hardware and software where possible. The conception and initial funding of this system originated with a study of ground-based imaging of global aerothermal characteristics of reusable launch vehicle configurations. During that study the National Aeronautics and Space Administration teamed with the Missile Defense Agency/Innovative Science and Technology Experimentation Facility to test techniques and analysis on two Space Shuttle flights.

Banks, Daniel W.↗
NASA NTRS2004

Preparing and Analyzing Iced Airfoils

SmaggIce version 1.2 is a computer program for preparing and analyzing iced airfoils. It includes interactive tools for (1) measuring ice-shape characteristics, (2) controlled smoothing of ice shapes, (3) curve discretization, (4) generation of artificial ice shapes, and (5) detection and correction of input errors. Measurements of ice shapes are essential for establishing relationships between characteristics of ice and effects of ice on airfoil performance. The shape-smoothing tool helps prepare ice shapes for use with already available grid-generation and computational-fluid-dynamics software for studying the aerodynamic effects of smoothed ice on airfoils. The artificial ice-shape generation tool supports parametric studies since ice-shape parameters can easily be controlled with the artificial ice. In such studies, artificial shapes generated by this program can supplement simulated ice obtained from icing research tunnels and real ice obtained from flight test under icing weather condition. SmaggIce also automatically detects geometry errors such as tangles or duplicate points in the boundary which may be introduced by digitization and provides tools to correct these. By use of interactive tools included in SmaggIce version 1.2, one can easily characterize ice shapes and prepare iced airfoils for grid generation and flow simulations.

Vickerman, Mary B.↗
NASA NTRS2012

Orion GN and C Model Based Development: Experience and Lessons Learned

The Orion Guidance Navigation and Control (GN&C) team is charged with developing GN&C algorithms for the Exploration Flight Test One (EFT-1) vehicle. The GN&C team is a joint team consisting primarily of Prime Contractor (Lockheed Martin) and NASA personnel and contractors. Early in the GN&C development cycle the team selected MATLAB/Simulink as the tool for developing GN&C algorithms and Mathworks autocode tools as the means for converting GN&C algorithms to flight software (FSW). This paper provides an assessment of the successes and problems encountered by the GN&C team from the perspective of Orion GN&C developers, integrators, FSW engineers and management. The Orion GN&C approach to graphical development, including simulation tools, standards development and autocode approaches are scored for the main activities that the team has completed through the development phases of the program.

Jackson, Mark C.↗
NASA NTRS1992

An improved approach for flight readiness certification: Probabilistic models for flaw propagation and turbine blade failure. Volume 1: Methodology and applications

An improved methodology for quantitatively evaluating failure risk of spaceflight systems to assess flight readiness and identify risk control measures is presented. This methodology, called Probabilistic Failure Assessment (PFA), combines operating experience from tests and flights with analytical modeling of failure phenomena to estimate failure risk. The PFA methodology is of particular value when information on which to base an assessment of failure risk, including test experience and knowledge of parameters used in analytical modeling, is expensive or difficult to acquire. The PFA methodology is a prescribed statistical structure in which analytical models that characterize failure phenomena are used conjointly with uncertainties about analysis parameters and/or modeling accuracy to estimate failure probability distributions for specific failure modes. These distributions can then be modified, by means of statistical procedures of the PFA methodology, to reflect any test or flight experience. State-of-the-art analytical models currently employed for designs failure prediction, or performance analysis are used in this methodology. The rationale for the statistical approach taken in the PFA methodology is discussed, the PFA methodology is described, and examples of its application to structural failure modes are presented. The engineering models and computer software used in fatigue crack growth and fatigue crack initiation applications are thoroughly documented.

Moore, N. R.↗