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All sourcesNASA NTRSDOE OSTI
NASA NTRS2012

Architecting the Human Space Flight Program with Systems Modeling Language (SysML)

The next generation of missions in NASA's Human Space Flight program focuses on the development and deployment of highly complex systems (e.g., Orion Multi-Purpose Crew Vehicle, Space Launch System, 21st Century Ground System) that will enable astronauts to venture beyond low Earth orbit and explore the moon, near-Earth asteroids, and beyond. Architecting these highly complex system-of-systems requires formal systems engineering techniques for managing the evolution of the technical features in the information exchange domain (e.g., data exchanges, communication networks, ground software) and also, formal correlation of the technical architecture to stakeholders' programmatic concerns (e.g., budget, schedule, risk) and design development (e.g., assumptions, constraints, trades, tracking of unknowns). This paper will describe how the authors have applied System Modeling Language (SysML) to implement model-based systems engineering for managing the description of the End-to-End Information System (EEIS) architecture and associated development activities and ultimately enables stakeholders to understand, reason, and answer questions about the EEIS under design for proposed lunar Exploration Missions 1 and 2 (EM-1 and EM-2).

scheduling↗
NASA NTRS1996

Dynamic Performance of High Bypass Ratio Turbine Engines With Water Ingestion

The research on dynamic performance of high bypass turbofan engines includes studies on inlets, turbomachinery and the total engine system operating with air-water mixture; the water may be in vapor, droplet, or film form, and their combinations. Prediction codes (WISGS, WINCOF, WINCOF-1, WINCLR, and Transient Engine Performance Code) for performance changes, as well as changes in blade-casing clearance, have been established and demonstrated in application to actual, generic engines. In view of the continuous changes in water distribution in turbomachinery, the performance of both components and the total engine system must be determined in a time-dependent mode; hence, the determination of clearance changes also requires a time-dependent approach. In general, the performance and clearances changes cannot be scaled either with respect to operating or ingestion conditions. Removal of water prior to phase change is the most effective means of avoiding ingestion effects. Sufficient background has been established to perform definitive, full scale tests on a set of components and a complete engine to establish engine control and operability with various air-water vapor-water mixtures.

Murthy, S. N. B.↗
NASA NTRS2004

Developing Advanced Support Technologies for Planetary Exploration Missions

The United States Vision for Space Exploration calls for sending robots and humans to explore the Earth s moon, the planet Mars, and beyond. The National Aeronautics and Space Administration (NASA) is developing a set of design reference missions that will provide further detail to these plans. Lunar missions are expected to provide a stepping stone, through operational research and evaluation, in developing the knowledge base necessary to send crews on long duration missions to Mars and other distant destinations. The NASA Exploration Systems Directorate (ExSD), in its program of bioastronautics research, manages the development of technologies that maintain human life, health, and performance in space. Using a systems engineering process and risk management methods, ExSD s Human Support Systems (HSS) Program selects and performs research and technology development in several critical areas and transfers the results of its efforts to NASA exploration mission/systems development programs in the form of developed technologies and new knowledge about the capabilities and constraints of systems required to support human existence beyond Low Earth Orbit. HSS efforts include the areas of advanced environmental monitoring and control, extravehicular activity, food technologies, life support systems, space human factors engineering, and systems integration of all these elements. The HSS Program provides a structured set of deliverable products to meet the needs of exploration programs. these products reduce the gaps that exist in our knowledge of and capabilities for human support for long duration, remote space missions. They also reduce the performance gap between the efficiency of current space systems and the greater efficiency that must be achieved to make human planetary exploration missions economically and logistically feasible. In conducting this research and technology development program, it is necessary for HSS technologists and program managers to develop a common currency for decision making and the allocation of funding. A high level assessment is made of both the knowledge gaps and the system performance gaps across the program s technical project portfolio. This allows decision making that assures proper emphasis areas and provides a key measure of annual technological progress, as exploration mission plans continue to mature.

Berdich, Debra P.↗
NASA NTRS2004

Developing Advanced Human Support Technologies for Planetary Exploration Missions

The United States Vision for Space Exploration calls for sending robots and humans to explore the Earth's moon, the planet Mars, and beyond. The National Aeronautics and Space Administration (NASA) is developing a set of design reference missions that will provide further detail to these plans. Lunar missions are expected to provide a stepping stone, through operational research and evaluation, in developing the knowledge base necessary to send crews on long duration missions to Mars and other distant destinations. The NASA Exploration Systems Directorate (ExSD), in its program of bioastronautics research, manages the development of technologies that maintain human life, health, and performance in space. Using a system engineering process and risk management methods, ExSD's Human Support Systems (HSS) Program selects and performs research and technology development in several critical areas and transfers the results of its efforts to NASA exploration mission/systems development programs in the form of developed technologies and new knowledge about the capabilities and constraints of systems required to support human existence beyond Low Earth Orbit. HSS efforts include the areas of advanced environmental monitoring and control, extravehicular activity, food technologies, life support systems, space human factors engineering, and systems integration of all these elements. The HSS Program provides a structured set of deliverable products to meet the needs of exploration programs. These products reduce the gaps that exist in our knowledge of and capabilities for human support for long duration, remote space missions. They also reduce the performance gap between the efficiency of current space systems and the greater efficiency that must be achieved to make human planetary exploration missions economically and logistically feasible. In conducting this research and technology development program, it is necessary for HSS technologists and program managers to develop a common currency for decision making and the allocation of funding. A high level assessment is made of both the knowledge gaps and the system performance gaps across the program s technical project portfolio. This allows decision making that assures proper emphasis areas and provides a key measure of annual technological progress, as exploration mission plans continue to mature.

Berdich, Debra P.↗
NASA NTRS1972

ERISTAR: Earth Resources Information Storage, Transformation, Analysis, and Retrieval administrative report

The 1972 Systems Engineering program at Marshall Space Flight Center where 15 participants representing 15 U.S. universities, 1 NASA/MSFC employee, and another specially assigned faculty member, participated in an 11-week program is discussed. The Fellows became acquainted with the philosophy of systems engineering, and as a training exercise, used this approach to produce a conceptional design for an Earth Resources Information Storage, Transformation, Analysis, and Retrieval System. The program was conducted in three phases; approximately 3 weeks were devoted to seminars, tours, and other presentations to subject the participants to technical and other aspects of the information management problem. The second phase, 5 weeks in length, consisted of evaluating alternative solutions to problems, effecting initial trade-offs and performing preliminary design studies and analyses. The last 3 weeks were occupied with final trade-off sessions, final design analyses and preparation of a final report and oral presentation.

Vachon, R. I.↗
NASA NTRS1998

Intelligent Systems and Advanced User Interfaces for Design, Operation, and Maintenance of Command Management Systems

Historically Command Management Systems (CMS) have been large, expensive, spacecraft-specific software systems that were costly to build, operate, and maintain. Current and emerging hardware, software, and user interface technologies may offer an opportunity to facilitate the initial formulation and design of a spacecraft-specific CMS as well as a to develop a more generic or a set of core components for CMS systems. Current MOC (mission operations center) hardware and software include Unix workstations, the C/C++ and Java programming languages, and X and Java window interfaces representations. This configuration provides the power and flexibility to support sophisticated systems and intelligent user interfaces that exploit state-of-the-art technologies in human-machine systems engineering, decision making, artificial intelligence, and software engineering. One of the goals of this research is to explore the extent to which technologies developed in the research laboratory can be productively applied in a complex system such as spacecraft command management. Initial examination of some of the issues in CMS design and operation suggests that application of technologies such as intelligent planning, case-based reasoning, design and analysis tools from a human-machine systems engineering point of view (e.g., operator and designer models) and human-computer interaction tools, (e.g., graphics, visualization, and animation), may provide significant savings in the design, operation, and maintenance of a spacecraft-specific CMS as well as continuity for CMS design and development across spacecraft with varying needs. The savings in this case is in software reuse at all stages of the software engineering process.

Mitchell, Christine M.↗
NASA NTRS2006

The Role of Project Science in the Chandra X-Ray Observatory

The Chandra X-Ray Observatory, one of NASA's Great Observatories, has an outstanding record of scientific and technical success. This success results from the efforts of a team comprising NASA, its contractors, the Smithsonian Astrophysical Observatory, the instrument groups, and other elements of the scientific community, including thousands of scientists who utilize this powerful facility for astrophysical research. We discuss the role of NASA Project Science in the formulation, development, calibration, and operation of the Chandra X-ray Observatory. In addition to representing the scientific community within the Project, Project Science performed what we term "science systems engineering". This activity encompasses translation of science requirements into technical requirements and assessment of the scientific impact of programmatic and technical trades. We briefly describe several examples of science systems engineering conducted by Chandra Project Science.

O'Dell, Stephen L.↗
NASA NTRS2013

Exploring Mission Concepts with the JPL Innovation Foundry A-Team

The JPL Innovation Foundry has established a new approach for exploring, developing, and evaluating early concepts called the A-Team. The A-Team combines innovative collaborative methods with subject matter expertise and analysis tools to help mature mission concepts. Science, implementation, and programmatic elements are all considered during an A-Team study. Methods are grouped by Concept Maturity Level (CML), from 1 through 3, including idea generation and capture (CML 1), initial feasibility assessment (CML 2), and trade space exploration (CML 3). Methods used for each CML are presented, and the key team roles are described from two points of view: innovative methods and technical expertise. A-Team roles for providing innovative methods include the facilitator, study lead, and assistant study lead. A-Team roles for providing technical expertise include the architect, lead systems engineer, and integration engineer. In addition to these key roles, each A-Team study is uniquely staffed to match the study topic and scope including subject matter experts, scientists, technologists, flight and instrument systems engineers, and program managers as needed. Advanced analysis and collaborative engineering tools (e.g. cost, science traceability, mission design, knowledge capture, study and analysis support infrastructure) are also under development for use in A-Team studies and will be discussed briefly. The A-Team facilities provide a constructive environment for innovative ideas from all aspects of mission formulation to eliminate isolated studies and come together early in the development cycle when they can provide the biggest impact. This paper provides an overview of the A-Team, its study processes, roles, methods, tools and facilities.

Team Eureka↗
NASA NTRS1989

Rocket plume spectrometry: A system permitting engine condition monitoring, as applied to the technology test bed engine

The appearance of visible objects in the exhaust plume of space shuttle main engines (SSME) during test firings is discussed. A program was undertaken to attempt to identify anomalous material resulting from wear, normal or excessive, of internal parts, allowing time monitoring of engine condition or detection of failure precursors. Measurements were taken during test firings at Stennis Space Center and at the Santa Suzanna facility in California. The results indicated that a system having high spectral resolution, a fast time response, and a wide spectral range was required to meet all requirements, thus two special systems have been designed and built. One is the Optical Plume Anomaly Detector (OPAD). The other instrument, which is described in this report, is the superspectrometer, an optical multichannel analyzer having 8,192 channels covering the spectral band 250 to 1,000 nm.

Powers, W. T.↗
NASA NTRS1990

Hypersonic aircraft design

A hypersonic aircraft is designed which uses scramjets to accelerate from Mach 6 to Mach 10 and sustain that speed for two minutes. Different propulsion systems were considered and it was decided that the aircraft would use one full scale turbofan-ramjet. Two solid rocket boosters were added to save fuel and help the aircraft pass through the transonic region. After considering aerodynamics, aircraft design, stability and control, cooling systems, mission profile, and landing systems, a conventional aircraft configuration was chosen over that of a waverider. The conventional design was chosen due to its landing characteristics and the relative expense compared to the waverider. Fuel requirements and the integration of the engine systems and their inlets are also taken into consideration in the final design. A hypersonic aircraft was designed which uses scramjets to accelerate from Mach 6 to Mach 10 and sustain that speed for two minutes. Different propulsion systems were considered and a full scale turbofan-ramjet was chosen. Two solid rocket boosters were added to save fuel and help the aircraft pass through the transonic reqion. After the aerodynamics, aircraft design, stability and control, cooling systems, mission profile, landing systems, and their physical interactions were considered, a conventional aircraft configuration was chosen over that of a waverider. The conventional design was chosen due to its landing characteristics and the relative expense compared to the waverider. Fuel requirements and the integration of the engine systems and their inlets were also considered in the designing process.

Alkamhawi, Hani↗
DOE OSTI2024

Preignition mitigation strategy for gaseous fuel engine

Operating a gaseous fuel engine system includes detecting preignition in one or more of a plurality of cylinders based on a monitored cylinder pressure during combustion of a gaseous fuel such as a gaseous hydrogen fuel. Operating a gaseous fuel engine system also includes reducing a fuel injection amount for the one or more of the plurality of cylinders to a derated fuel injection amount that is based on a timing of the detected preignition. Fuel injection amount may be reduced to a greater relative extent if detected preignition is early, and to a lesser relative extent if detected preignition is later, in an engine cycle. Related apparatus and control logic is also disclosed.

Graziano, Jr., Michael T.↗
NASA NTRS2021

Model-Based SMA Initiative Phase 1 Report: Reliability Tips Excerpt

The emergence of model-based engineering, with Model- Based Systems Engineering (MBSE) leading the way, is transforming design and analysis methodologies. [7] The recognized benefits to systems development include moving from document-centric information systems and document-centric project communication to a model-centric environment in which control of design changes in the life cycles is facilitated. In addition, a “single source of truth” about the system, that is up-to-date in all respects of the design, becomes the authoritative source of data and information about the system. This promotes consistency and efficiency in regard to integration of the system elements as the design emerges and thereby may further optimize the designs. Therefore Reliability Engineers (REs) supporting NASA missions must be integrated into model-based engineering, using these recommended modeling techniques, to ensure the outputs of their analyses are relevant and value-needed to the design, development, and operational processes for failure risk assessment and communication.

Nancy J. Lindsey↗
NASA NTRSDate not supplied

Analysis of the Value Added When Deploying a Model-Based Approach for the Validation and Verification of the Medical Database Software

The Medical Database (MD) is a virtual repository consisting of two software components: Medical Item Database (MedID) and the Evidence Library (EL). MedID consists of engineering data and associated information for specific medical resource items (e.g., pharmaceutical, medical devices, and supporting components), while the EL is a tool which provides all of the medical evidence necessary. The MD will 1) serve as the single “source of truth” for the Informing Mission Planning via Analysis of Complex Tradespaces (IMPACT) tool suite for both medical evidence and medical resource engineering data and 2) will be used in conjunction with the IMPACT tool suite to inform research prioritizations and perform systematic trade study evaluations to aid stakeholders in making informed decisions regarding simulated human spaceflight missions. The MD project used a Model-Based Systems Engineering (MBSE) approach to support all life cycles of the software development, while in parallel the human factors engineering team used modeling to support Human Centered Design (HCD) strategies in an effort to improve software usability. HCD is a frequently used approach in design frameworks that develops resolutions to complexities and challenges by involving the human perspective in all steps of the problem-solving process. By integrating the model-based approaches used for systems engineering and human factors activities, the project is able to leverage the model-based artifacts originally created for HCD activities for system level and human factors validation. In this presentation, our team highlights the value added when leveraging these model-based artifacts to support the on-going verification and validation activities.

C. Laing↗
NASA NTRS2003

Evaluation and Characterization Study of Dual Pulse Laser-Induced Spark (DPLIS) for Rocket Engine Ignition System Application

This paper addresses the progress of technology development of a laser ignition system at NASA Marshall Space Flight Center (MSFC). Laser ignition has been used at MSFC in recent test series to successfully ignite RP1/GOX propellants in a subscale rocket chamber, and other past studies by NASA GRC have demonstrated the use of laser ignition for rocket engines. Despite the progress made in the study of this ignition method, the logistics of depositing laser sparks inside a rocket chamber have prohibited its use. However, recent advances in laser designs, the use of fiber optics, and studies of multi-pulse laser formats3 have renewed the interest of rocket designers in this state-of the-art technology which offers the potential elimination of torch igniter systems and their associated mechanical parts, as well as toxic hypergolic ignition systems. In support of this interest to develop an alternative ignition system that meets the risk-reduction demands of Next Generation Launch Technology (NGLT), characterization studies of a dual pulse laser format for laser-induced spark ignition are underway at MSFC. Results obtained at MSFC indicate that a dual pulse format can produce plasmas that absorb the laser energy as efficiently as a single pulse format, yet provide a longer plasma lifetime. In an experiments with lean H2/air propellants, the dual pulse laser format, containing the same total energy of a single laser pulse, produced a spark that was superior in its ability to provide sustained ignition of fuel-lean H2/air propellants. The results from these experiments are being used to optimize a dual pulse laser format for future subscale rocket chamber tests. Besides the ignition enhancement, the dual pulse technique provides a practical way to distribute and deliver laser light to the combustion chamber, an important consideration given the limitation of peak power that can be delivered through optical fibers. With this knowledge, scientists and engineers at Los Alamos National Laboratory and CFD Research Corporation have designed and fabricated a miniaturized, first-generation optical prototype of a laser ignition system that could be the basis for a laser ignition system for rocket applications. This prototype will be tested at MSFC in future subscale rocket ignition tests.

Osborne, Robin↗
DOE OSTI2020

Engineering microscale systems for fully autonomous intracellular neural interfaces

Conventional electrodes and associated positioning systems for intracellular recording from single neurons in vitro and in vivo are large and bulky, which has largely limited their scalability. Further, acquiring successful intracellular recordings is very tedious, requiring a high degree of skill not readily achieved in a typical laboratory. We report here a robotic, MEMS-based intracellular recording system to overcome the above limitations associated with form-factor, scalability and highly skilled and tedious manual operations required for intracellular recordings. This system combines three distinct technologies: 1) novel microscale, glass-polysilicon penetrating electrode for intracellular recording, 2) electrothermal microactuators for precise microscale movement of each electrode and 3) closed-loop control algorithm for autonomous positioning of electrode inside single neurons. Here, we demonstrate the novel, fully integrated system of glass-polysilicon microelectrode, microscale actuators and controller for autonomous intracellular recordings from single neurons in the abdominal ganglion of Aplysia Californica (n = 5 cells). Consistent resting potentials (< –35 mV) and action potentials (> 60 mV) were recorded after each successful penetration attempt with the controller and microactuated glass-polysilicon microelectrodes. The success rate of penetration and quality of intracellular recordings achieved using electrothermal microactuators were comparable to that of conventional positioning systems. The MEMS-based system offers significant advantages: 1) reduction in overall size for potential use in behaving animals, 2) scalable approach to potentially realize multi-channel recordings and 3) a viable method to fully automate measurement of intracellular recordings. Furthermore, this system will be evaluated in vivo in future rodent studies.

42 ENGINEERING↗
NASA NTRS2007

Nuclear Thermal Propulsion (NTP) Development Activities at the NASA Marshall Space Flight Center - 2006 Accomplishments

In 2005-06, the Prometheus program funded a number of tasks at the NASA-Marshall Space Flight Center (MSFC) to support development of a Nuclear Thermal Propulsion (NTP) system for future manned exploration missions. These tasks include the following: 1. NTP Design Develop Test & Evaluate (DDT&E) Planning 2. NTP Mission & Systems Analysis / Stage Concepts & Engine Requirements 3. NTP Engine System Trade Space Analysis and Studies 4. NTP Engine Ground Test Facility Assessment 5. Non-Nuclear Environmental Simulator (NTREES) 6. Non-Nuclear Materials Fabrication & Evaluation 7. Multi-Physics TCA Modeling. This presentation is a overview of these tasks and their accomplishments

Ballard, Richard O.↗