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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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The Cassini spacecraft fault protection design includes fault monitors that use a state-space architecture to monitor the performance of spacecraft functions.
Mission-Aware Cyber Safe Mode (MACSM) is spacecraft resilience architecture that enables autonomous containment of software-level cyber intrusions while maintaining control authority and mission continuity. It is analogous to traditional safe modes that preserve vehicle survival by shutting down non-essential subsystems in response to faults or environmental stress.
Papers are presented on such topics as nuclear survivability concepts for airborne computers, military aerospace computer trends, a management approach to acquiring computer systems, software acquisition and verification, and future aerospace digital signal processing concepts. Also considered are CCD architecture for spacecraft SAR image processing, avionics software development for the B-1 aircraft, and software sneak analysis.
Earth science research and application requirements for multispectral data have often been driven by currently available remote sensing technology. Few parametric studies exist that specify data required for certain applications. Consequently, data requirements are often defined based on the best data available or on what has worked successfully in the past. Since properties such as spatial resolution, swath width, spectral bands, signal-to-noise ratio (SNR), data quantization and band-to-band registration drive sensor platform and spacecraft system architecture and cost, analysis of these criteria is important to optimize system design objectively. Remote sensing data requirements are also linked to calibration and characterization methods. Parameters such as spatial resolution, radiometric accuracy and geopositional accuracy affect the complexity and cost of calibration methods. However, few studies have quantified the true accuracies required for specific problems. As calibration methods and standards are proposed, it is important that they be tied to well-known data requirements. The Application Research Toolbox (ART) developed at the John C. Stennis Space Center provides a simulation-based method for multispectral data requirements development. The ART produces simulated datasets from hyperspectral data through band synthesis. Parameters such as spectral band shape and width, SNR, data quantization, spatial resolution and band-to-band registration can be varied to create many different simulated data products. Simulated data utility can then be assessed for different applications so that requirements can be better understood.
Formation estimation methodologies for distributed spacecraft systems are formulated and analyzed. A generic form of the formation estimation problem is described by defining a common hardware configuration, observation graph, and feasible estimation topologies.
On January 14, 2004, the President of the United States announced a new plan to explore space and extend a human presence across our solar system. The National Aeronautics and Space Administration (NASA) established the Exploration Systems Mission Directorate (ESMD) to develop and field a Constellation Architecture that will bring the Space Exploration vision to fruition. The Constellation Architecture includes a human-rated Crew Launch Vehicle (CLV) segment, managed by the Marshall Space Flight Center (MSFC), comprised of the First Stage (FS), Upper Stage (US), and Upper Stage Engine (USE) elements. The CLV s purpose is to provide safe and reliable crew and cargo transportation into Low Earth Orbit (LEO), as well as insertion into trans-lunar trajectories. The architecture's Spacecraft segment includes, among other elements, the Crew Exploration Vehicle (CEV), managed by the Johnson Space Flight Center (JSC), which is launched atop the CLV. MSFC is also responsible for CLV and CEV stack integration. This paper provides an overview of the Avionics and Software integration approach (which includes the Integrated System Health Management (ISHM) functions), both within the CLV, and across the CEV interface; it addresses the requirements to be met, logistics of meeting those requirements, and the roles of the various groups. The Avionics Integration and Vehicle Systems Test (ANST) Office was established at the MSFC with system engineering responsibilities for defining and developing the integrated CLV Avionics and Software system. The AIVST Office has defined two Groups, the Avionics and Software Integration Group (AVSIG), and the Integrated System Simulation and Test Integration Group (ISSTIG), and four Panels which will direct trade studies and analyses to ensure the CLV avionics and software meet CLV system and CEV interface requirements. The four panels are: 1) Avionics Integration Panel (AIP), 2) Software Integration Panel, 3) EEE Panel, and 4) Systems Simulation and Test Panel. Membership on the groups and panels includes the MSFC representatives from the requisite engineering disciplines, the First Stage, the Upper Stage, the Upper Stage Engine projects, and key personnel from other NASA centers. The four panels will take the results of trade studies and analyses and develop documentation in support of Design Analysis Cycle Reviews and ultimately the System Requirements Review.
The advance in solid state light emitting technologies and optics for lighting and visual communication necessitates the evaluation of how NASA envisions spacecraft lighting architectures and how NASA uses industry standards for the design and evaluation of lighting systems. Current NASA lighting standards and requirements for existing architectures focus on the separate ability of a lighting system to throw light against a surface or the ability of a display system to provide the appropriate visual contrast. This project investigated large luminous surface lamps as an alternative or supplement to overhead lighting. The efficiency of the technology was evaluated for uniformity and power consumption.
Future human space exploration will most likely be composed of assemblies of multiple modular spacecraft elements with interconnected electrical power systems. An electrical system composed of a standardized set modular building blocks provides significant development, integration, and operational cost advantages. The modular approach can also provide the flexibility to configure power systems to meet the mission needs. A primary goal of the Advanced Exploration Systems (AES) Modular Power System (AMPS) project is to establish a Modular Power Standard that is needed to realize these benefits. This paper is intended to give the space exploration community a "first look" at the evolving Modular Power Standard and invite their comments and technical contributions.
No abstract available
In this paper, the authors propose a new process for the development and operation of inmanned vehicles for the exploration of space. We call the vehicle Sciencecraft to distinguish it from the more traditional vehicle Spacecraft. A Sciencecraft is an integrated unit that combines science instruments, electronics, telecommunications, power, and propulsion elements into a single system.
This paper describes CopScanner, a new component of the Copernicus ecosystem for spacecraft trajectory design and optimization. CopScanner is a Python library being developed at the NASA JSC which enables easy parallelization of Copernicus scans. CopScanner is currently being developed and implemented for production of Copernicus trajectory scans for upcoming Artemis Missions (Artemis II and beyond). On the backend, CopScanner utilizes Dask, an open-source Python library for parallel computing which enables parallelization over both multi-core local machines and large-scale distributed computing clusters. CopScanner abstracts the trajectory scanning process into a DAG which is constructed using a chain of individual subscans. Each node in the DAG executes a python module, called the callable, for which there are built-in defaults, or users may specify their own. Support for custom callables makes CopScanner a versatile trajectory optimization software. All output files and associated metadata from a CopScanner scan are compressed and stored in a two-file output, collectively called the FileStore, consisting of a SQLite database and a compressed JSON MessagePack file, for which CopScanner provides a Python class for interaction.
Lockheed, the Hubble Space Telescope mission operations contractor, is currently engaged in a project to develop a distributed architecture of communicating expert systems to support vehicle operations. This architecture, called Telemetry Analysis for Lockheed Operated Spacecraft (TALOS), has potentially wide applicability to spacecraft operations. The architecture mirrors the organization of the human experts within an operations control center. The prototype analyzes telemetry from a history tape to determine the state of the vehicle with respect to on-board safemode events. The prototype is currently being expanded along two fronts. One consists of expert systems modules which perform deeper level diagnostics and which operate in an off-line mode. The other is a high speed front-end expert system which will monitor real time telemetry for anomalies and spacecraft status and send activation and initialization messages to the off-line modules when an anomaly is detected.
Lockheed, the Hubble Space Telescope Mission Operations Contractor, is currently engaged in a project to develop a distributed architecture of communicating expert systems to support vehicle operations. This architecture, named Telemetry Analysis Logic for Operating Spacecraft (TALOS), has the potential for wide applicability in spacecraft operations. The architecture mirrors the organization of the human experts within an operations control center.
The Cassini spacecraft will perform a detailed examination of the Saturnian system, including the release of a probe to study Saturn's largest satellite, Titan. The star tracker for the Cassini mission must provide accurate data during the entire flight including four years of measurement in a harsh radiation environment.
The Cassini spacecraft will launch October 1997 and will perform a detailed examination of the Saturnian system, including the release of a probe to study Saturn's Largest satellite, Titan. The star tracker for the Cassini mission must provide accurate data during the 12 years of flight including four years of mesurement in a harsh radiation environment.
As the technology that enables advanced deep space autonomous navigation continues to develop and the requirements for such capability continues to grow, there is a clear need for a modular expandable simulation framework. This tool's purpose is to address multiple measurement and information sources in order to capture system capability. This is needed to analyze the capability of competing navigation systems as well as to develop system requirements, in order to determine its effect on the sizing of the integrated vehicle. The development for such a framework is built upon Model-Based Systems Engineering techniques to capture the architecture of the navigation system and possible state measurements and observations to feed into the simulation implementation structure. These models also allow a common environment for the capture of an increasingly complex operational architecture, involving multiple spacecraft, ground stations, and communication networks. In order to address these architectural developments, a framework of agent-based modules is implemented to capture the independent operations of individual spacecraft as well as the network interactions amongst spacecraft. This paper describes the development of this framework, and the modeling processes used to capture a deep space navigation system. Additionally, a sample implementation describing a concept of network-based navigation utilizing digitally transmitted data packets is described in detail. This developed package shows the capability of the modeling framework, including its modularity, analysis capabilities, and its unification back to the overall system requirements and definition.
Spacecraft designs are driven by the payloads and mission requirements that they support. Many of the payload characteristics, such as mass, power requirements, communication requirements, moving parts, and so forth directly affect the choices for the spacecraft structural configuration and its subsystem design and component selection. The conceptual design process, which translates mission requirements into early spacecraft concepts, must be tolerant of frequent changes in the payload complement and resource requirements. A computer data base was designed and implemented for the purposes of containing the payload characteristics pertinent for spacecraft conceptual design, tracking the evolution of these payloads over time, and enabling the integration of the payload data with engineering analysis programs for improving the efficiency in producing spacecraft designs. In-house tools were used for constructing the data base and for performing the actual integration with an existing program for optimizing payload mass locations on the spacecraft.