- API data.nasa.gov | Last Updated 2018-07-18T20:02:06.000Z
Academy of Program/Project & Engineering Leadership's Annual Report highlights the Academy's efforts to serve the NASA workforce's needs in adapting to the challenges of today and the future.
- API data.nasa.gov | Last Updated 2018-07-19T11:16:28.000Z
High resolution spectroscopy with thermal detectors shows great promise for making astrophysical discoveries across the electromagnetic spectrum, from radio to gamma-rays. These investigations are critical to advancing our understanding of many astrophysical problems related to investigating the structure and evolution of the universe and the origins of the elements, all fundamental NASA goals. Transition Edge Sensor microcalorimeters and bolometers have been highly successful in ground and balloon-based experiments, and technology development is underway to take the next step and operate a TES array in space. Transition Edge Sensors are a versatile and still-developing technology, with applications ranging from astrophysical investigations like the cosmic microwave background and X-ray spectroscopy to potential industrial applications like compact, high resolution X-ray microanalysis instruments. The goal of my investigation is to develop transition edge sensor technology that can be used for a new space-based application, the study of the diffuse soft x-ray background. Diffuse background studies make stringent demands on many different aspects of detector design. Therefore, the new TES technology developed in such an investigation can benefit a variety of applications. With this in mind, my research plan includes learning about space hardware and instrumentation by preparing for a sounding rocket flight that will obtain a high resolution spectrum of the soft X-ray background with a thermistor microcalorimeter array. This will help me build a solid background in instrument science, which I will apply to overcoming the technical challenges associated with building a large-area high energy resolution array of transition edge sensors needed to study the diffuse background.
- API data.nasa.gov | Last Updated 2018-07-19T08:29:02.000Z
Radiation-cooled, bipropellant thrust chambers are being considered for the ascent/descent engines and reaction control systems for NASA missions such as Mars Sample Return and Orion MPCV. Currently, iridium-lined rhenium combustion chambers are the state-of-the-art for in-space engines. NASA's Advanced Materials Bipropellant Rocket (AMBR) engine, a 150-lbf iridium-rhenium chamber produced by Plasma Processes and Aerojet, recently set a hydrazine specific impulse record of 333.5 seconds. To withstand the high loads during terrestrial launch, rhenium chambers with improved mechanical properties are needed. Recent EL-FormTM results have shown considerable promise for improving the mechanical properties of rhenium by producing a multi-layered deposit comprised of a tailored microstructure, i.e., Engineered Re. During Phase I, an AMBR size chamber was produced to demonstrate formation of the Engineered Re material in both the throat and barrel regions. Tensile tests showed the Engineered Re material had a yield strength greater than 40ksi at room temperature. In addition, Engineered Re deposits were produced on multiple mandrels at one time, i.e., multi-component process demonstration. During Phase II, the Engineered Re processing techniques will be optimized. Detailed characterization and mechanical properties test will be performed. Optimization of the multi-component fabrication technique will result in a 30% or higher reduction in chamber fabrication costs. The most promising techniques will be selected and used to produce an Engineered Re AMBR size combustion chamber for testing at Aerojet.
- API data.nasa.gov | Last Updated 2018-07-19T10:09:14.000Z
This project will further MBSE technology in fundamental ways by strengthening the link between SysML tools and framework engineering execution environments. Phoenix Integration has produced a commercial tool (MBSE Pak) which allows engineers to link SysML diagrams (in MagicDraw and Rhapsody) to ModelCenter, a general-purpose engineering integration framework. As a result, from SysML parametric diagrams, engineers can execute actual engineering analysis tools for the purpose of systems architectural design, requirements compliance, trade studies, etc. This proposal would extend this MBSE product in several specific ways. First, it would develop a systems analysis capability for improved management decisions including the ability to perform what-if studies of technology options, simulation of schedule and cost, and probabilistic discrete event simulation for risk analysis. Second, it would improve verification and validation of models through improved requirements compliance analysis, handling of time series data, and traceability of data pedigree for modeling artifacts. Third, it would connect SysML models to executable model libraries in which components can be executed in an ad-hoc manner (on any capable computer) from the library itself and include rich support for multi-fidelity modeling tools on the backend. A representative system model would be developed as an example problem to illustrate the developed features and would be demonstrated to NASA throughout the course of the work.
- API data.nasa.gov | Last Updated 2018-07-19T07:28:36.000Z
A heliogyro spacecraft is a specific type of solar sail that generates thrust from the reflection of solar photons. The proposed research for this fellowship will address the limitations of current analytic models and control designs for a heliogyro spacecraft to develop practical solutions. The first objective is to derive new equations of motion for the essential blade dynamics. The reduced order model for a heliogyro spacecraft will include multiple degrees of freedom, coupled dynamics, solar radiation pressure loading and torque source boundary conditions, all of which are lacking from the current analytic models. The second objective is to develop a root control system that effectively damps the structural modes of a heliogyro spacecraft. The final objective is to determine the blade behavior during initial spin-up of the spacecraft and blade deployment. The main methods used to accomplish these research objectives will include classical control theory in conjunction with impedance control and a thorough understanding of the blade dynamics. The heliogyro spacecraft modeling will begin with simplified linear assumptions. The coupling and nonlinearities will be added incrementally to the model. The propellant-free heliogyro is a long-duration sustainable spacecraft whose maneuverability allows it to attain previously inaccessible orbits for traditional spacecraft. Continuing research in practical heliogyro control will significantly advance the TRL of this innovative design, in turn lowering the cost of existing missions and opening up exciting new mission possibilities.
- API data.nasa.gov | Last Updated 2018-07-19T07:30:17.000Z
Mars planetary surface access is one of NASA's biggest technical challenges involving advanced entry, descent, and landing (EDL) technologies and methods. This NASA Innovative Advanced Concept (NIAC) project intends to solve one of the top challenges for landing large payloads and humans on Mars by using advanced atmospheric In-Situ Resource Utilization (ISRU) methods that have never been tried or studied before. The proposed Mars Molniya Orbit Atmospheric Resource Mining concept mission architecture will make Mars travel routine and affordable for cargo and crew, therefore enabling the expansion of human civilization to Mars.
- API data.nasa.gov | Last Updated 2018-09-07T17:39:46.000Z
<p>Future astrophysics missions require efficient, low-temperature cryocoolers to cool advanced instruments or serve as the upper stage cooler for sub-Kelvin refrigerators. Potential astrophysics missions include Lynx, the Origin Space Telescope, and the Superconducting Gravity Gradiometer. Cooling loads for these missions are up to 300 mW at temperatures of 4 to 10 K, with additional loads at higher temperatures for other subsystems. Due to low jitter requirements, a cryocooler with very low vibration is needed for many missions. In addition, a multi-stage cooler, capable of providing refrigeration at more than one temperature simultaneously, can provide the greatest system efficiency with the lowest mass. Turbo-Brayton cryocoolers have space heritage and are ideal for these missions due to negligible vibration emittance and high efficiency at low temperatures. The primary limitation in implementing Brayton cryocoolers at temperatures below 10 K has been the development of high efficiency turbines. On the proposed program, Creare plans to leverage recent developments in gas bearing technology and low-temperature alternators to realize a high-efficiency, low-temperature turbine. On the Phase I project, we will perform a proof-of-concept demonstration of the turbine technology at temperatures down to 4 K. On the Phase II project, we will build and demonstrate an advanced low-temperature turbine at temperatures of 4 to 10 K.</p>
- API data.nasa.gov | Last Updated 2018-07-19T12:33:59.000Z
M4 Engineering proposes to implement physics-based, multidisciplinary analysis and optimization objects that will be integrated into a Python, open-source framework and used in a wide variety of simulations. The integrated objects will perform discipline-specific analysis across multiple flight regimes at varying levels of fidelity. The process will also deliver system-level, multi-objective optimization. Addressing physics-based, system-level objectives that span more than one discipline will have profound effects on improving decision-making abilities during the conceptual design phase when evaluating advanced technological concepts. In the proposed effort, existing capabilities will be leveraged to create a high fidelity, physics based, multidisciplinary analysis and optimization (MDAO) system. This proposed work will compliment M4 Engineering's expertise in developing modeling and simulation toolsets that solve relevant subsonic, supersonic, and hypersonic demonstration applications.
- API data.nasa.gov | Last Updated 2018-07-19T08:38:04.000Z
<p>We propose to enhance GSFC’s interplanetary mission design capability by designing a fully automated multi-spacecraft multi-objective interplanetary global trajectory optimization transcription. Advanced trajectory design technologies including the ability to design Distributed Spacecraft Missions (DSMs) are attracting increased interest but no mission design tool is currently capable of performing mission and systems design/optimization for an interplanetary DSM. This effort will deliver a software prototype capable of building the optimal design of a DSM-class mission where multiple spacecraft depart to the heliocentric regime from the same launch vehicle to perform coordinated science. This new capability will lay the groundwork for a follow-on proposal to implement this new capability into NASA Goddard's Evolutionary Mission Trajectory Generator (EMTG) where it will enable new announcements of opportunity for Distributed Spacecraft Missions.</p>
Towards Sub-mm Level Formation Knowledge and mm-Level Control of Distributed Spacecraft for Earth Remote Sensing Using Small Satellitesdata.nasa.gov | Last Updated 2018-09-05T23:05:08.000Z
<p>Task to research technologies enabling precision formation flight of small spacecraft in a fuel efficient manner. The task focuses on two key technologies, the first, is building more precise sensors for determining relative spacecraft position, the second, is to build novel Guidance Navigation and Control formation flight architectures.</p><p>This tasks matures two technologies needed for Earth sensing distributed spacecraft missions beyond 2025. The first is high performance inter-spacecraft positioning, time-transfer, and communications. The second is the guidance, navigation, and control (GNC) formation flight architectures to leverage this technology and demonstrate fuel-efficient yet precise LEO formation control. Relative Positioning with GPS/GNSS: Modify the miniaturized low-power GPS/GNSS space receiver (uGNSS), developed during a previous task, to demonstrate real-time relative positioning between two spacecraft to sub-centimeter level accuracy. This will be accomplished by passing GNSS carrier phase and range measurements via the inter-spacecraft link, using JPL’s Real-Time GNSS-inferred positioning system-x (RTGx) to solve for the inter-spacecraft baselines. Inter-Spacecraft: Ranging, Time Transfer, and Communication: Build a prototype dual-frequency transceiver with commercial off-the-shelve (COTS) components, demonstrating sub-mm relative positioning. This inter-spacecraft link will be used for precise ranging, time transfer, and communications between multiple spacecraft, leveraging software and algorithms developed for GRACE/GRAIL. Formation Flight: The objective of the formation flight (FF) sub-task is to develop prototype GNC architectures that enable economic missions. Through analysis, formation architectures will be assessed based on these new sensing capabilities. The study will directly apply the predicted performance of the inter-spacecraft ranging subsystem being developed in parallel.</p>