Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “process development”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,207 records · Page 67
All sourcesNASA NTRSDOE OSTI
NASA NTRS2017

Application of CFS to a Lunar Rover: Resource Prospector (RP)

Resource Prospector (RP) is a lunar mission sponsored by NASA's Advanced Exploration Systems (AES) division, that aims to study in-situ resource utilization (ISRU) feasibility and technologies on the surface of the moon. The RP mission's lunar surface segment includes a rover equipped with with a suite of instruments specifically designed to measure and map volatiles both at the surface and in the subsurface. Of particular interest is the quantity and state of volatiles in permanently shadowed regions. To conduct the mission, ground system operators will remotely drive the rover, directing it to waypoints along the surface in order to achieve measurement objectives. At selected locations, an onboard drill will be deployed to collect material and obtain direct measurements of the subsurface constituents. RP is currently planned for launch in 2022. RP is managed at NASA Ames Research Center. The RP Rover is being designed and developed by NASA Johnson Space Center (JSC) in partnership with NASA Ames. NASA Kennedy Space Center (KSC) is responsible for the Honeybee drilling system and science payload. In order to better understand the technical challenges and demonstrate capability, in 2015 the RP project developed a rover testbed (known as RP15). In this mission in a year, a rover was designed, developed, and outfitted with science instruments and a drill. The rover was operated from a remote operations center, and operated in an outdoor lunar rock yard at Johnson space center. The study was a resounding success meeting all objectives. The RP Rover software architecture and development processes were based on the successful Lunar Atmosphere and Dust Environment Explorer spacecraft. This architecture is built on the Core Flight System software and an interface to Matlab/Simulink auto-generated software components known as the Simulink Interface Layer (SIL). The application of this lunar satellite inspired framework worked well for the rover application, and is currently being planned for the mission. This presentation provides an overview of the architecture and processes, and describes some of the changes and challenges for the rover application.

RP↗
NASA NTRS2018

Nasa's Launch Communications Ground Segment for the 21st Century Florida Spaceport

The National Aeronautics and Space Administration (NASA) Near Earth Network (NEN) Project is implementing a new launch communications ground segment to provide services for the next generation of human and robotic space exploration systems. It will deliver unique and advanced capabilities to accelerate the transformation of Kennedy Space Center into a multi-user spaceport in cooperation with the United States Air Force (USAF). The project has leveraged commercial technologies and remote operations concepts matured in NASAs orbiting satellite ground systems to achieve dramatic lifecycle cost efficiencies as compared to the space shuttle-era ground segment. The purpose of this paper is to discuss the development history, capabilities and anticipated use cases of the NEN Launch Communications Segment (NEN LCS).The NASA Kennedy Space Center is co-located with the USAF Eastern Launch Range at Cape Canaveral, Florida. The USAF operates two launch communications ground stations, but they are not designed to transmit voice, commands or other data to the launch vehicle or astronauts. The bi-directional uplink-downlink communications responsibility for human missions has historically resided with the Goddard Space Flight Center in Greenbelt, Maryland. Several market analyses and feasibility studies investigating concepts to provide NASAs next generation launch communications services were performed during the Constellation Program prior to its cancellation in 2009, and as part of the Kennedy Space Centers follow-on efforts to transform itself into a 21st century multi-user spaceport. In 2012, the Kennedy Space Center and the USAF 45th Space Wing jointly led a study to analyze the market needs of current and future launch systems and assess the operational deficiencies of the Eastern Range infrastructure. The study team issued several recommendations, two of which ultimately became driving operational capability requirements for the NEN LCS: increased telemetry data rates of at least 20 Mbps, and S-band uplink capability. Additional capabilities identified in the requirements development process include spread spectrum modulation support, LDPC 12 and 78 error correction codes, support for IRIG-106 and CCSDS data formats, automated best source selection, and Space Link Extension (SLE) services for data distribution. The NEN LCS is comprised of two permanent ground stations, the new Kennedy Uplink Station (KUS) and refurbished Ponce de Leon (PDL) station. Both stations are remotely operated from the Global Monitor and Control Center at Wallops Flight Facility. This core architecture is extensible through host-tenant arrangements with the U.S. Air Force and deployable assets, enabling agile, tailored and robust solutions to meet the needs of civil, commercial or military customers. The NEN LCS has three use cases:1.To provide agile, tailored and robust launch communications solutions to Florida spaceport customers2.To provide orbital communications services to near-earth customers 3.To provide an experimental proving ground for Space Mobile Network concepts and technologies The NEN LCS driving mission is to support the bi-directional link with the Orion crew capsule and two 20 Mbps telemetry links from the Space Launch System core stage on Exploration Mission-1, the first integrated flight of NASAs flagship human exploration systems.

Roberts, Christopher J.↗
NASA NTRS2018

Marrying Social Media Approaches and Space Flight Control - Eight Years at SpaceOps

This paper shows how Marshall Space Flight Center's (MSFC) ISS Payload Operations Integration Center (POIC) is realizing the above goals via a) enhancements to the Console Log Tool (CoLT) first deployed in 2012 and b) the Communications Dashboard (CommDash) software suite deployed in 2017. In addition to technical discussion, the paper chronicles CommDash's role in emergence of an Agile development process and a Human Factors community of practice within MSFC's Payload Mission Operations Division (PMOD).

Scott, D. W.↗
NASA NTRS2018

Development of a High Speed Rain Impact Capability

Enhancement of a 2-stage light gas gun capability is under development at NASA Marshall Space Flight Center for the purpose of making rain impacts on nose cone and window materials. This paper will discuss current capabilities of this gun system and the path it took to get there. The end goal is to be able to provide realistic rain and thermal environments, simulating rain impact conditions of high speed flight (combined effects). In the past year, the ability to create impacts to simulate rain using 2, 3, and 4 mm Nylon beads in the 7,000-10,000 ft/s (2.13-3.05 km/s) range at room temperature has been demonstrated. It is desired to extend this range down to 6000 ft/s (1.83 km/s) for rain impact purposes. The size range capability will also be extended to launch particles 1 mm and smaller. In addition, a heating capability is being added to the system to potentially cover a temperature range from room temperature to 5000 F. Hydrogen light gas will extend the velocity range to 23,000-26,000 ft/s (7-8 km/s), simulating orbital debris impacts for vehicles that spend a significant amount of time in space. Particle impact precision will also be evaluated during this development process.

Gray, Perry↗
NASA NTRS2018

Orientation Effects in Two-Phase Microgap Flow

The high power density of emerging electronic devices is driving the transition from remote cooling, which relies on con-duction and spreading, to embedded cooling, which extracts dissipated heat on-site. Two-phase microgap coolers employ the forced flow of dielectric fluids undergoing phase change in a heated channel within or between devices. Such coolers must work reliably in all orientations for a variety of applications (e.g., vehicle-based equipment), as well as in microgravity and high-g for other applications (e.g., spacecraft and aircraft). The lack of acceptable models and correlations for orientation- and gravity-independent operation has limited the use of two-phase coolers in such applications. Previous research has revealed that gravita-tional acceleration plays a diminishing role in establishing flow regimes and transport rates as the channel size shrinks, but there is considerable variation among the proposed microscale criteria and limited research on two-phase flows in low aspect ratio mi-crogap channels. Reliable criteria for achieving orientation- and gravity-independent flow boiling would enable emerging sys-tems to exploit this thermal management technique and streamline the technology development process. As a first step toward understanding the effect of gravity on two-phase microgap flow and transport, in the present effort the authors have studied the effect of evaporator orientation and mass flux on near-saturated flow boiling of HFE7100 in a 1.01 mm tall by 13.0 mm wide by 12.7 mm long microgap channel. Orientation-independence, defined as achieving similar critical heat fluxes, heat transfer coefficients, and flow regimes across evaporator orientations, was achieved for mass fluxes of 400 kg/m2-s and greater. The present results are compared to pub-lished criteria for achieving gravity-independence.

orientation↗
NASA NTRS2018

Orientation Effects in Two-Phase Microgap Flow

The high power density of emerging electronic devices is driving the transition from remote cooling, which relies onconduction and spreading, to embedded cooling, which extracts dissipated heat on-site. Two-phase microgap coolersemploy the forced flow of dielectric fluids undergoing phase change in a heated channel within or between devices. Such coolers must work reliably in all orientations for a variety of applications (e.g., vehicle-based equipment), as well as in microgravity and high-g for other applications (e.g., spacecraft and aircraft). The lack of acceptable models andcorrelations for orientation- and gravity-independent operation has limited the use of two-phase coolers in suchapplications. Previous research has revealed that gravitational acceleration plays a diminishing role in establishing flow regimes and transport rates as the channel size shrinks, but there is considerable variation among the proposed microscale criteria and limited research on two-phase flows in low aspect ratio microgap channels. Reliable criteria for achieving orientation- and gravity-independent flow boiling would enable emerging systems to exploit this thermal management technique and streamline the technology development process.

orientation↗
NASA NTRS2018

Collaborative Data Curation to Support the Multi-Mission Algorithm and Analysis Platform (MAAP)

Upcoming space-borne missions will offer unprecedented data about Earth but will also feature exponentially high data volumes. These high data volumes will change the way the scientific community works with data and will also create a unique need for improved data sharing and collaboration. NASA and ESA are working together to address these issues by collaboratively developing the Multi-Mission Algorithm and Analysis Platform (MAAP) to improve the understanding of global aboveground terrestrial carbon dynamics. The MAAP will support ESA’s BIOMASS mission, NASA’s GEDI mission and NASA/ISRO’s NISAR mission. The MAAP will be developed in two phases: a pilot phase and a full production phase. The pilot phase will demonstrate collaboration and basic capabilities. The pilot phase will focus on biomass relevant airborne and field campaign data. Two NASA teams are supporting the development of the MAAP. The MAAP engineering team is responsible for the development, maintenance and operations of the MAAP system while the MAAP data team ensures the ongoing quality of the data, metadata and other information provided in the MAAP. The MAAP data team also supports the ingest and archive of identified data to the MAAP platform. This poster describes the use case development process for the pilot MAAP and the data curated in support of those use cases. Additionally, this presentation will outline the pilot MAAP data ingest process and metadata curation effort along with efforts to ensure interoperability between ESA and NASA data and metadata.

Bugbee, Kaylin↗
NASA NTRS2019

Development of an Additively Manufactured Capacitive Humidity Sensor for the International Space Station

The ability to measure humidity on the International Space Station and other long-duration spaceflight missions is a crucial part of the onboard systems. For example, the Environmental Control and Life Support System (ECLSS) needs to know the amount of humidity in the air to make decisions about whether it should spend power to run the dehumidifier systems to attempt to reclaim that water. Other issues can arise if the humidity reaches too high of levels and condensation builds up on electrical components. With that in mind, it is vital that the spacecraft keeps spare sensors on board or has the ability to manufacture new sensors on demand. An additively manufactured sensor would be additionally beneficial because it would save space onboard that would normally be taken up by spares, save money from costly resupply missions, and allow the sensor to be constantly updated with the most effective design. This Technical Memorandum outlines a development process carried out to design, manufacture, and test an additively manufactured humidity sensor.

Chang, K. T.↗
NASA NTRS2019

Improved Processing Techniques for Inclusion-Free Steel for Bearing and Mechanical Component Applications

High hardness, high carbide powder metallurgy tools steels such as M62 enable the operation of ball bearings at extremely high load and stress levels. Operation under such conditions increases the potential for rolling contact fatigue failure attributed to ceramic particle inclusions. To address this challenge, industry has sought steel made from ever increasing levels of cleanliness but the results have been uneven owing to the random nature of the occurrence of material flaws. One common approach is to rely upon careful ingot inspections prior to bearing manufacture. By selecting the cleanest portion of an ingot, it is expected that bearings relatively free from material flaws will result. This approach is not always successful because detrimental flaws that exist deep within an ingot can pass inspection undetected potentially causing subsequent failure. Recent efforts to commercialize an intermetallic material, 60NiTi, for rolling element bearings demonstrates a pathway to produce bearing steel that is free from unwanted ceramic particle inclusions. In this paper, the process used to make bearing grade ceramic-free NiTi alloys is described and applied to steelmaking. At its core, the NiTi process differs from steel making in one key aspect. NiTi alloys are made from elementally pure starting materials that are melted, blended and processed in equipment absolutely free from exposure to oxygen and ceramics ensuring a ceramic particle-free product. In contrast, the predominant method to make bearing steel is to employ a successive series of purification steps to reduce contamination levels below required thresholds. This paper describes the processes developed and applied to high carbide tool steel, M62. The resulting material and microstructures are evaluated and compared to M62 prepared by conventional powder metallurgy techniques. It is hoped that the application of materials manufacturing techniques used for fracture sensitive ceramics and intermetallic materials like NiTi can provide a pathway to Ultra-Clean, Ceramic-Inclusion free steels for rolling element bearings and other failure critical applications.

Steel↗
NASA NTRS2019

Simulation and Flight Test Environments for the TASAR Traffic Aware Planner

The Traffic Aware Planner (TAP) software is a flight deck decision support tool that enhances the flight crew’s ability to make flight-optimizing route change requests while airborne. The software provides conflict-free, optimized trajectory suggestions during en route flight to produce time- and fuel-savings compared to the current trajectory. The TAP software requires evaluation in an operational environment with real pilot users to validate projected benefits. To this end, a set of developmental test environments have been developed to mature the software and mitigate technical risk prior to entering operational evaluation. The unique attributes of each test environment were leveraged to provide a range of purpose- and case-dependent TAP software tests. This paper describes the elements of a testing environment, discusses several environments of varying fidelity used to test the TAP software, and provides a review of two case studies highlighting the vital role testing played in the TAP software development process.

Barney, Terique L.↗
NASA NTRS2019

Gravity Effects in Two-Phase Microgap Flow

The high power density of emerging electronic devices is driving the transition from remote cooling, which relies on conduction and spreading, to embedded cooling, which extracts dissipated heat on-site. Two-phase microgap coolers employ the forced flow of dielectric fluids undergoing phase change in a heated channel within or between devices. Such coolers must work reliably in all orientations for a variety of applications (e.g., vehicle-based equipment), as well as in microgravity and high-g for aerospace applications, but the lack of acceptable models and correlations for orientation- and gravity-independent operation has limited their use. Reliable criteria for achieving orientation- and gravity-independent flow boiling would enable emerging systems to exploit this thermal management technique and streamline the technology development process. As a first step toward understanding the effect of gravity in two-phase microgap flow and transport, in an earlier effort, the authors studied the effects of evaporator orientation, mass flux, and heat flux on flow boiling of HFE7100 in a 1.01 mm tall by 13.0 mm wide by 12.7 mm long microgap channel. Orientation-independence, defined as achieving similar critical heat fluxes, heat transfer coefficients, and flow regimes across orientations, was achieved for mass fluxes of 400 kg/sq.m-s and greater (corresponding to a Froude number of about 0.8). In the present effort, the authors have studied the effects of gravity, mass flux, and subcooling on flow boiling of HFE7100 in a 0.17 mm tall by 13.0 mm wide by 12.7 mm long microgap channel. The Flow Boiling in Microgap Coolers payload experienced about three minutes of weightlessness and shorter periods of high-g (up to about 5 g) during two recent flights aboard the Blue Origin New Shepard reusable launch vehicle. The results from the flight experiments will be presented and compared with published criteria for achieving gravity-independence.

Robinson, Franklin L.↗
NASA NTRS2019

Standards and Best Practices - Two NASA Examples

Formal international standards as well as promotion of community or recommended practices have their place in ensuring "FAIRness" of data. Data management in NASA's Earth Observation System Data and Information System (EOSDIS) has benefited from both of these avenues to a significant extent. The purpose of this paper is to present one example of each of these, which promote (re)usability. The first is an ISO standard for specifying preservation content from Earth observation missions. The work on this started in 2011, informally within the Earth Science Information Partners (ESIP) in the US, while the European Space Agency (ESA) was leading an effort on Long-Term Data Preservation (LTDP). Resulting from the ESIP discussions was NASA's Preservation Content Specification, which was applied in 2012 as a requirement for NASA's new missions. ESA's Preserved Data Set Content (PDSC) document was codified into a document adopted by the Committee on Earth Observation Satellites (CEOS). It was recognized that it would be useful to combine PCS and PDSC into an ISO standard to ensure consistency in data preservation on a broader international scale. This standard, numbered ISO 19165-2 has been under development since mid-2017. The second is an example of developing recommendations for "best practices" within more limited (still fairly broad) communities. A Data Product Developers' Guide (DPDG) is currently being developed by one of NASA's Earth Science Data System Working Groups (ESDSWGs). It is for use by developers of products to be derived from Earth observation data to improve product (re)usability. One of the challenges in developing the guide is the fact that there are already many applicable standards and guides. The relevant information needs to be selected and expressed in a succinct manner, with appropriate pointers to references. The DPDG aims to compile the most applicable parts of earlier guides into a single document outlining the typical development process for Earth Science data products. Standards and best practices formally endorsed by the Earth Science Data and Information System (ESDIS) Standards Office (ESO), outputs from ESDSWGs (e.g., Dataset Interoperability Working Group, and Data Quality Working Group), and recommendations from Distributed Active Archive Centers and data producers are emphasized.

Ramapriyan, Hampapuram↗
NASA NTRS2019

Modeling Meteoroid Densities for Spacecraft Risk Assessment

This report describes the methodologies and algorithms that NASA’s Meteoroid Environment Office (MEO) currently utilizes to measure meteoroid densities. We discuss the needs for an accurate model for the meteoroid density distribution in its Meteoroid Engineering Model (MEM), and its potential implications for spacecraft design. The recently developed process is heavily derived from that of previous work, although subtle differences exist. A thorough comparison of the best-fit densities derived for sixty meteoroids in and with the process described here shows that discrepancies in final densities larger than a factor of two are measured for ∼ 20% of our test events. Such a level of discrepancy suggests that any density calculated using similar methods cannot be assumed to represent a unique fit to the data. Additional observational data for meteoroids beyond those utilized in this work will be essential for producing more reliable and repeatable density measurements.

Ehlert, Steven↗
NASA NTRSDate not supplied

Astrobee Free-Flyer Nozzle Mechanism

This paper describes the development and design of the Astrobee Free-Flyer propulsion nozzle assemblies. As will be illustrated in this paper, the Free-Flyer nozzles are thrust control devices used to propel the Astrobee Free-Flyer robot autonomously inside the International Space Station (ISS). The development process, design evolution, and prototyping methods, are described. Key design features are discussed in greater detail to highlight how a seemingly simple design can present surprisingly large challenges. Several lessons learned are given.

Earl Daley↗
NASA NTRSDate not supplied

cFS Test Framework (CTF)

NASA's Core Flight System (cFS) provides a generic flight software framework architecture for developing flight software. As the cFS framework has gained popularity over the years within the flight software community, supporting software tools have been developed to assist in the design, development, testing and verification of flight software. The cFS Test Framework (CTF) is a recently developed cFS tool with capabilities to develop and run automated test and verification scripts against flight software targets. The CTF tool parses and executes JSON-based test scripts containing test instructions, while logging and reporting the results. CTF utilizes a plugin-based architecture to allow developers to extend CTF with new test instructions, external interfaces, and custom functionality. To interface with flight software, CTF parses a set of CCSDS message definition files to create the necessary command and telemetry structures for use during the test run. Additionally, CTF also supports interfacing with multiple cFS instances, allowing a test script to verify requirements that involve multiple flight software targets. Lastly, CTF provides support for executing test scripts against FSW running on remote or embedded hardware. This allows CTF to execute the same test scripts across different target configurations throughout the development process. In this presentation, we will introduce the cFS Test Framework (CTF) architecture, discuss the history of cFS testing frameworks, and present the features and capabilities currently provided by CTF. Lastly, we will show a demo of the CTF tool being used to execute test scripts against flight software.

Aly I Shehata↗
NASA NTRS2021

MBSE Validation and Verification: Case Study for LADEE

The Lunar Atmosphere Dust Environment Explorer (LADEE) mission orbited the moon in order to measure the density, composition, and time variability of the lunar dust environment. The successful mission launched September 7, 2013 and was de-orbited and impacted the moon's surface on April 17, 2014. The ground-side and onboard flight software for the mission was developed using a “Model-Based Software Engineering” (MBSE) methodology combined with strong reuse of Government and Commercial Off-The Shelf (G/COTS) components. Models of the spacecraft and flight software were developed in a graphical dynamics modeling package. Flight Software requirements were prototyped and refined using the simulated models. After the model was shown to work as desired in the simulation framework, C-code software was automatically generated from the models. The auto-generated software was then tested in real-time Processor-in-the-Loop and Hardware-in-the-Loop test beds. “Traveling Road Show” test beds were used for early integration tests with payloads and other subsystems. Traditional techniques for verifying computational sciences models were used to characterize the spacecraft simulation. A lightweight set of formal methods analysis, static analysis, formal inspection, and code coverage analyses were utilized to further reduce defects in the onboard flight software artifacts. These techniques were applied early and often in the development process, iteratively increasing the capabilities of software and fidelity of vehicle models and test beds.

Model-Based Software Engineering, Validation and V↗