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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 487 records · Page 27

All sources NASA NTRS DOE OSTI

NASA NTRS1986

Manned Mars mission environmental control and life support subsystem

A specific design is not presented, but the general philosophy regarding potential Environmental Control/Life Support System (ECLSS) requirements, concepts, issues, and technology needs are discussed. The focus is on a manned Mars mission occurring in the late 1990's. Discussions on the Trans-Mars Vehicle, the Mars Excursion Module (MEM), and a Martian base facility are covered. The functions, performance requirements, and design loads of a typical ECLSS are listed, and the issues and technology briefly discussed. Several ECLSS concepts and options are identified, and comparative weights and volumes are provided for these. Several aspects of the space station ECLSS are contrasted with the Mars element ECLSS.

Hueter, Uwe↗

NASA NTRS1979

In-orbit evaluation of the control system/structural mode interactions of the OSO-8 spacecraft

The Orbiting Solar Observatory-8 experienced severe structural mode/control loop interaction problems during the spacecraft development. Extensive analytical studies, using the hybrid coordinate modeling approach, and comprehensive ground testing were carried out in order to achieve the system's precision pointing performance requirements. A recent series of flight tests were conducted with the spacecraft in which a wide bandwidth, high resolution telemetry system was utilized to evaluate the on-orbit flexible dynamics characteristics of the vehicle along with the control system performance. The paper describes the results of these tests, reviewing the basic design problem, analytical approach taken, ground test philosophy, and on-orbit testing. Data from the tests was used to determine the primary mode frequency, damping, and servo coupling dynamics for the on-orbit condition. Additionally, the test results have verified analytically predicted differences between the on-orbit and ground test environments, and have led to a validation of both the analytical modeling and servo design techniques used during the development of the control system.

Slafer, L. I.↗

NASA NTRS1980

On-orbit evaluation of the control system/structural mode interactions on OSO-8

The Orbiting Solar Observatory-8 experienced severe structural mode/control loop interaction problems during the spacecraft development. Extensive analytical studies, using the hybrid coordinate modeling approach, and comprehensive ground testing were carried out in order to achieve the system's precision pointing performance requirements. A recent series of flight tests were conducted with the spacecraft in which a wide bandwidth, high resolution telemetry system was utilized to evaluate the on-orbit flexible dynamics characteristics of the vehicle along with the control system performance. This paper describes the results of these tests, reviewing the basic design problem, analytical approach taken, ground test philosophy, and on-orbit testing. Data from the tests was used to determine the primary mode frequency, damping, and servo coupling dynamics for the on-orbit condition. Additionally, the test results have verified analytically predicted differences between the on-orbit and ground test environments. The test results have led to a validation of both the analytical modeling and servo design techniques used during the development of the control system, and also verified the approach taken to vehicle and servo ground testing.

Slafer, L. I.↗

NASA NTRS1982

Thermal design and experiment thermal integration of the Long Duration Exposure Facility

The Long Duration Exposure Facility (LDEF) is a large (14 feet diameter by 30 feet long) Shuttle transported, reusable spacecraft. The LDEF can accommodate up to 13,000 pounds of experiments mounted in 86 standard trays. This paper describes the philosophy and approach used for the passive thermal design of the LDEF. Also discussed are the standardized guidelines and techniques used in the thermal design and integration of approximately 50 different thermally passive experiments. A technique for reducing multinode thermal models of experiments to 2 nodes is also presented. This approach allows the efficient thermal integration of large numbers of experiments with the LDEF spacecraft.

Greene, R. F., Jr.↗

NASA NTRS1989

THREAD: A programming environment for interactive planning-level robotics applications

THREAD programming language, which was developed to meet the needs of researchers in developing robotics applications that perform such tasks as grasp, trajectory design, sensor data analysis, and interfacing with external subsystems in order to perform servo-level control of manipulators and real time sensing is discussed. The philosophy behind THREAD, the issues which entered into its design, and the features of the language are discussed from the viewpoint of researchers who want to develop algorithms in a simulation environment, and from those who want to implement physical robotics systems. The detailed functions of the many complex robotics algorithms and tools which are part of the language are not explained, but an overall impression of their capability is given.

Beahan, John J., Jr.↗

NASA NTRS2003

Early Flight Fission Test Facilities (EFF-TF) and Concepts That Support Near-Term Space Fission Missions

Fission technology can enable rapid, affordable access to any point in the solar system. If fusion propulsion systems are to be developed to their full potential; however, near-term customers must be identified and initial fission systems successfully developed, launched, and utilized. Successful utilization will most likely occur if frequent, significant hardware-based milestones can be achieved throughout the program. If the system is designed to operate within established radiation damage and fuel burn up limits while simultaneously being designed to allow close simulation of heat from fission using resistance heaters, high confidence in fission system pe$ormance and lifetime can be attained through non-nuclear testing. Through demonstration of systems concepts (designed by DOE National Laboratories) in relevant environments, this philosophy has been demonstrated through hardware testing in the Early Flight Fission Test Facilities (EFF-TF) at the Marshall Space Flight Center. The EFF-TF is designed to enable very realistic non-nuclear testing of space fission systems. Ongoing research at the EFF-TF is geared towards facilitating research, development, system integration, and system utilization via cooperative efforts with DOE labs, industry, universities, and other NASA centers.

VanDyke, Melissa↗

NASA NTRS1993

Object-oriented technologies in a multi-mission data system

The Operations Engineering Laboratory (OEL) at JPL is developing new technologies that can provide more efficient and productive ways of doing business in flight operations. Over the past three years, we have worked closely with the Multi-Mission Control Team to develop automation tools, providing technology transfer into operations and resulting in substantial cost savings and error reduction. The OEL development philosophy is characterized by object-oriented design, extensive reusability of code, and an iterative development model with active participation of the end users. Through our work, the benefits of object-oriented design became apparent for use in mission control data systems. Object-oriented technologies and how they can be used in a mission control center to improve efficiency and productivity are explained. The current research and development efforts in the JPL Operations Engineering Laboratory are also discussed to architect and prototype a new paradigm for mission control operations based on object-oriented concepts.

Murphy, Susan C.↗

NASA NTRS1994

Method for optimizing resource allocation in a government organization

The managers in Federal agencies are challenged to control the extensive activities in government and still provide high-quality products and services to the American taxpayers. Considering today's complex social and economic environment and the $3.8 billion daily cost of operating the Federal Government, it is evident that there is a need to develop decision-making tools for accurate resource allocation and total quality management. The goal of this thesis is to provide a methodical process that will aid managers in Federal Government to make budgetary decisions based on the cost of services, the agency's objectives, and the customers' perception of the agency's product. A general resource allocation procedure was developed in this study that can be applied to any government organization. A government organization, hereafter the 'organization,' is assumed to be a multidivision enterprise. This procedure was applied to a small organization for the proof of the concept. This organization is the Technical Services Directorate (TSD) at the NASA Lewis Research Center in Cleveland, Ohio. As part of the procedure, a nonlinear programming model was developed to account for the resources of the organization, the outputs produced by the organization, the decision-maker's views, and the customers' satisfaction with the organization. The information on the resources of the organization was acquired from current budget levels of the organization and the human resources assigned to the divisions. The outputs of the organization were defined and measured by identifying metrics that assess the outputs, the most challenging task in this study. The decision-maker's views are represented in the model as weights assigned to the various outputs and were quantified by using the analytic hierarchy process. The customer's opinions regarding the outputs of the organization were collected through questionnaires that were designed for each division individually. Following the philosophy of total quality management, information on customers' satisfaction is presented in the model as the quality of output. The model is a nonlinear one whose objective is to maximize customers' satisfaction such that the total cost of operation does not exceed the organization's budget. This model represents a structured approach or policy mechanism, at the agency level, to make capital investment decisions based on the priorities of the agency and the quality of outputs. This procedure applied to TSD resulted in a resources allocation scheme that was reasonable and acceptable to the decision-makers and, as expected, dependent on the assumptions and accuracy of the data used in the model.

Afarin, James↗

NASA NTRS1998

Integration of a CAD System Into an MDO Framework

NASA Langley has developed a heterogeneous distributed computing environment, called the Framework for Inter-disciplinary Design Optimization, or FIDO. Its purpose has been to demonstrate framework technical feasibility and usefulness for optimizing the preliminary design of complex systems and to provide a working environment for testing optimization schemes. Its initial implementation has been for a simplified model of preliminary design of a high-speed civil transport. Upgrades being considered for the FIDO system include a more complete geometry description, required by high-fidelity aerodynamics and structures codes and based on a commercial Computer Aided Design (CAD) system. This report presents the philosophy behind some of the decisions that have shaped the FIDO system and gives a brief case study of the problems and successes encountered in integrating a CAD system into the FEDO framework.

Townsend, J. C.↗

NASA NTRS2014

Spacecraft Environmental Testing SMAP (Soil, Moisture, Active, Passive)

Testing a complete full up spacecraft to verify it will survive the environment, in which it will be exposed to during its mission, is a formidable task in itself. However, the ''test like you fly'' philosophy sometimes gets compromised because of cost, design and or time. This paper describes the thermal-vacuum and mass properties testing of the Soil Moisture Active Passive (SMAP) earth orbiting satellite. SMAP will provide global observations of soil moisture and freeze/thaw state (the hydrosphere state). SMAP hydrosphere state measurements will be used to enhance understanding of processes that link the water, energy, and carbon cycles, and to extend the capabilities of weather and climate prediction models. It will explain the problems encountered, and the solutions developed, which minimized the risk typically associated with such an arduous process. Also discussed, the future of testing on expensive long lead-time spacecraft. Will we ever reach the ''build and shoot" scenario with minimal or no verification testing?

thermal↗

NASA NTRS2000

Generalized Philosophy of Alerting with Applications for Parallel Approach Collision Prevention

The goal of the research was to develop formal guidelines for the design of hazard avoidance systems. An alerting system is automation designed to reduce the likelihood of undesirable outcomes that are due to rare failures in a human-controlled system. It accomplishes this by monitoring the system, and issuing warning messages to the human operators when thought necessary to head off a problem. On examination of existing and recently proposed logics for alerting it appears that few commonly accepted principles guide the design process. Different logics intended to address the same hazards may take disparate forms and emphasize different aspects of performance, because each reflects the intuitive priorities of a different designer. Because performance must be satisfactory to all users of an alerting system (implying a universal meaning of acceptable performance) and not just one designer, a proposed logic often undergoes significant piecemeal modification before gamma general acceptance. This report is an initial attempt to clarify the common performance goals by which an alerting system is ultimately judged. A better understanding of these goals will hopefully allow designers to reach the final logic in a quicker, more direct and repeatable manner. As a case study, this report compares three alerting logics for collision prevention during independent approaches to parallel runways, and outlines a fourth alternative incorporating elements of the first three, but satisfying stated requirements. Three existing logics for parallel approach alerting are described. Each follows from different intuitive principles. The logics are presented as examples of three "philosophies" of alerting system design.

Winder, Lee F.↗

NASA NTRS1985

Research in the design of high-performance reconfigurable systems

The initial control and programming philosophies of the RELAPSE are discussed. A block diagram showing the relationship of the Arithmetic Units (composed of Stages and Bit Processors), to the Functional Units, and other components of the RELAPSE is used to guide this discussion. The latest version of the Bit Processor design is presented. Included is a detailed discussion of the Bit Processor's new scratch pad memory component. The section also clarifies the usage of the Bit Processor's processing registers, and Input/Output functions. The final design phase of the Arithmetic Unit is underway by a study of the Proposed IEEE Floating Point Standard. The decisions on conformation to this standard will be used as inputs into the finalization of the designs of the Bit Processor, Stage, and Arithmetic Units of the RELAPSE.

Slotnick, D. L.↗

NASA NTRS1989

Air transportation in the California Corridor of 2010

The topic of the 1988-1989 NASA/USRA Advanced Design Project at California Polytechnic State University, San Luis Obispo, was the development of an air transportation system to meet the needs of the California Corridor for the year 2010. As aircraft design is taught by two instructors having different philosophies about the teaching process, the two classes took different approaches to address the problem. The first part of this summary (California Air Transit System) represents the work done by the students of Professor A. E. Andreoli, who followed a systems approach, emphasizing the determination of the proper mission. The second part of the summary (Four Aircraft to Service the California Corridor) contains the four aircraft designed by Dr. D. R. Sandlin's class based on specifications determined from work done in previous years.

Cameron, M.↗

NASA NTRS1983

Introduction to human factors considerations in system design

A definition for human factors or ergonomics and its industrial and domestic application is presented. Human factors engineering, which discovers and applies information about human abilities, limitations, and other characteristics to the design of tools, machines, systems, tasks, jobs, and environments for safe, comfortable, and effective human use, is outlined. The origins of human factors and ergonomics, the philosophy of human factors, goals and objectives, systems development and design, are reviewed.

Chapanis, A.↗

NASA NTRS1991

Philosophy, policies, and procedures - The three P's of flight-deck operations

Standard operating procedures are drafted and provided to flightcrews to dictate the manner in which tasks are carried out. Failure to conform to Standard Operating Procedures (SOP) is frequently listed as the cause of violations, incidents, and accidents. However, procedures are often designed piecemeal, rather than being based on a sound philosophy of operations and policies that follow from such a philosophy. A framework of philosophy, policies, and procedures is proposed.

Degani, Asaf↗

NASA NTRS1997

Advanced Technology Composite Fuselage - Repair and Damage Assessment Supporting Maintenance

Under the NASA-sponsored contracts for Advanced Technology Composite Aircraft Structures (ATCAS) and Materials Development Omnibus Contract (MDOC), Boeing is studying the technologies associated with the application of composite materials to commercial transport fuselage structure. Included in the study is the incorporation of maintainability and repairability requirements of composite primary structure into the design. This contractor report describes activities performed to address maintenance issues in composite fuselage applications. A key aspect of the study was the development of a maintenance philosophy which included consideration of maintenance issues early in the design cycle, multiple repair options, and airline participation in design trades. Fuselage design evaluations considered trade-offs between structural weight, damage resistance/tolerance (repair frequency), and inspection burdens. Analysis methods were developed to assess structural residual strength in the presence of damage, and to evaluate repair design concepts. Repair designs were created with a focus on mechanically fastened concepts for skin/stringer structure and bonded concepts for sandwich structure. Both a large crown (skintstringer) and keel (sandwich) panel were repaired. A compression test of the keel panel indicated the demonstrated repairs recovered ultimate load capability. In conjunction with the design and manufacturing developments, inspection methods were investigated for their potential to evaluate damaged structure and verify the integrity of completed repairs.

Flynn, B. W.↗

NASA NTRS2009

Approach for Mitigating Pressure Garment Design Risks in a Mobile Lunar Surface Systems Architecture

The stated goals of the 2004 Vision for Space Exploration focus on establishing a human presence throughout the solar system beginning with the establishment of a permanent human presence on the Moon. However, the precise objectives to be accomplished on the lunar surface and the optimal system architecture to achieve those objectives have been a topic of much debate since the inception of the Constellation Program. There are two basic styles of system architectures being traded at the Programmatic level: a traditional large outpost that would focus on techniques for survival off our home planet and a greater depth of exploration within one area, or a mobile approach- akin to a series of nomadic camps- that would allow greater breadth of exploration opportunities. The traditional outpost philosophy is well within the understood pressure garment design space with respect to developing interfaces and operational life cycle models. The mobile outpost, however, combines many unknowns with respect to pressure garment performance and reliability that could dramatically affect the cost and schedule risks associated with the Constellation space suit system. This paper provides an overview of the concepts being traded for a mobile architecture from the operations and hardware implementation perspective, describes the primary risks to the Constellation pressure garment associated with each of the concepts, and summarizes the approach necessary to quantify the pressure garment design risks to enable the Constellation Program to make informed decisions when deciding on an overall lunar surface systems architecture.

Aitchison, Lindsay↗

NASA NTRS1974

Advanced composite structures

A monograph is presented which establishes structural design criteria and recommends practices to ensure the design of sound composite structures, including composite-reinforced metal structures. (It does not discuss design criteria for fiber-glass composites and such advanced composite materials as beryllium wire or sapphire whiskers in a matrix material.) Although the criteria were developed for aircraft applications, they are general enough to be applicable to space vehicles and missiles as well. The monograph covers four broad areas: (1) materials, (2) design, (3) fracture control, and (4) design verification. The materials portion deals with such subjects as material system design, material design levels, and material characterization. The design portion includes panel, shell, and joint design, applied loads, internal loads, design factors, reliability, and maintainability. Fracture control includes such items as stress concentrations, service-life philosophy, and the management plan for control of fracture-related aspects of structural design using composite materials. Design verification discusses ways to prove flightworthiness.

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