Engineering PapersSearch

SEARCH · Engineering Papers

Results for “Work assignments”

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 55 records · Page 3

Space Electronic Test Engineering

The Space Power and Propulsion Test Engineering Branch at NASA Glenn Research center has the important duty of controlling electronic test engineering services. These services include test planning and early assessment of Space projects, management and/or technical support required to safely and effectively prepare the article and facility for testing, operation of test facilities, and validation/delivery of data to customer. The Space Electronic Test Engineering Branch is assigned electronic test engineering responsibility for the GRC Space Simulation, Microgravity, Cryogenic, and Combustion Test Facilities. While working with the Space Power and Propulsion Test Engineering Branch I am working on several different assignments. My primary assignment deals with an electrical hardware unit known as Sunny Boy. Sunny Boy is a DC load Bank that is designed for solar arrays in which it is used to convert DC power form the solar arrays into AC power at 60 hertz to pump back into the electricity grid. However, there are some researchers who decided that they would like to use the Sunny Boy unit in a space simulation as a DC load bank for a space shuttle or even the International Space Station hardware. In order to do so I must create a communication link between a computer and the Sunny Boy unit so that I can preset a few of the limits (such power, set & constant voltage levels) that Sunny Boy will need to operate using the applied DC load. Apart from this assignment I am also working on a hi-tech circuit that I need to have built at a researcher s request. This is a high voltage analog to digital circuit that will be used to record data from space ion propulsion rocket booster tests. The problem that makes building this circuit so difficult is that it contains high voltage we must find a way to lower the voltage signal before the data is transferred into the computer to be read. The solution to this problem was to transport the signal using infrared light which will lower the voltage signal down low enough so that it is harmless to a computer. Along with my involvement in the Space Power and Propulsion Test Engineering Branch, I am obligated to assist all other members of the branch in their work. This will help me to strengthen and extend my knowledge of Electrical Engineering.

Chambers, Rodney D.

Ares Launch Vehicles Development Awakens Historic Test Stands at NASA's Marshall Space Flight Center

This paper chronicles the rebirth of two national rocket testing assets located at NASA's Marshall Space Flight Center: the Dynamic Test Stand (also known as the Ground Vibration Test Stand) and the Static Test Stand (also known as the Main Propulsion Test Stand). It will touch on the historical significance of these special facilities, while introducing the requirements driving modifications for testing a new generation space transportation system, which is set to come on line after the Space Shuttle is retired in 2010. In many ways, America's journey to explore the Moon begins at the Marshall Center, which is developing the Ares I crew launch vehicle and the Ares V cargo launch vehicle, along with managing the Lunar Precursor Robotic Program and leading the Lunar Lander descent stage work, among other Constellation Program assignments. An important component of this work is housed in Marshall's Engineering Directorate, which manages more than 40 facilities capable of a full spectrum of rocket and space transportation technology testing - from small components to full-up engine systems. The engineers and technicians who operate these test facilities have more than a thousand years of combined experience in this highly specialized field. Marshall has one of the few government test groups in the United States with responsibility for the overall performance of a test program from conception to completion. The Test Laboratory has facilities dating back to the early 1960s, when the test stands needed for the Apollo Program and other scientific endeavors were commissioned and built along the Marshall Center's southern boundary, with logistics access by air, railroad, and barge or boat on the Tennessee River. NASA and its industry partners are designing and developing a new human-rated system based on the requirements for safe, reliable, and cost-effective transportation solutions. Given below are summaries of the Dynamic Test Stand and the Static Test Stand capabilities, along with an introduction to the new missions that these sleeping giants will be fulfilling as NASA readies the Ares I for service in the 2015 timeframe, and plans the development work for fielding the Ares V late next decade (fig. 1). Validating modern computer design models and techniques requires the sorts of data that can only be generated by these one-of-a-kind facilities.

Dumbacher, Daniel L.

Revisiting the assignment of atomic charges in metal oxides based on core-level x-ray photoelectron spectra: The case of Ti in SrTiO3(001)

We demonstrate that assigning formal charges to transition metal (TM) cations based on core-level (CL) x-ray photoemission binding energies in oxides leads to physically inconsistent pictures of electronic structure. O 2p–TM 3d hybridization is well known to result in significant covalency in TM–O bonds, thereby reducing TM cation charges from their fully ionic values. However, the ionic bonding model remains the working paradigm for assigning TM CL features, and the resulting cation charges are often taken to be representative of the material under study. Here, we show that a more physically meaningful way to assign charges is to extract information about charge distributions utilizing Dirac–Hartree–Fock theory to calculate CL spectra from first principles and then use the resulting wave functions to determine charges based on orbital occupancies. TM cation charges can also be determined using density functional theory and Bader population analysis. We illustrate these two methods using the Ti 2p spectrum for SrTiO3(001) and show that the agreement between them is excellent. Significantly, the resulting Ti charge is considerably lower than the formal charge. The high degree of similarity between the Ti 2p spectrum for SrTiO3 and those for the rutile and anatase polymorphs of TiO2 suggests that the charge densities surrounding Ti in the latter materials are similar to that in SrTiO3. Taking a broader perspective, oxides containing other first-row transition metals also exhibit covalent character, leading to TM cation charges lower than the analogous fully ionic values in these materials as well.

Chambers, Scott A. (ORCID:000000025415043X)

Space Station Workstation Technology Workshop Report

This report describes the results of a workshop conducted at Goddard Space Flight Center (GSFC) to identify current and anticipated trends in human-computer interface technology that may influence the design or operation of a space station workstation. The workshop was attended by approximately 40 persons from government and academia who were selected for their expertise in some aspect of human-machine interaction research. The focus of the workshop was a 1 1/2 brainstorming/forecasting session in which the attendees were assigned to interdisciplinary working groups and instructed to develop predictions for each of the following technology areas: (1) user interface, (2) resource management, (3) control language, (4) data base systems, (5) automatic software development, (6) communications, (7) training, and (8) simulation. This report is significant in that it provides a unique perspective on workstation design for the space station. This perspective, which is characterized by a major emphasis on user requirements, should be most valuable to Phase B contractors involved in design development of the space station workstation. One of the more compelling results of the workshop is the recognition that no major technological breakthroughs are required to implement the current workstation concept. What is required is the creative application of existing knowledge and technology.

Moe, K. L.

Goodard Space Flight Center/Wallops Flight Facility airborne geoscience support capability

Goddard Space Flight Center's Wallops Facility (GSFC/WFF), operates six aircraft which are used as airborne geoscience platforms. The aircraft complement consists of two UH-1B helicopters, one twin engine Skyvan, one twin jet T-39, and two four engine turboprop aircraft (P-3 and Electra) offering the research community a wide range of payload, altitude, speed, and range capabilities. WFF's support to a principal investigator include mission planning of all supporting elements, installation of equipment on the aircraft, fabrication of brackets, and adapters as required to adapt payloads to the aircraft, and planning of mission profiles to meet science objectives. The flight regime includes local, regional, and global missions. The WFF aircraft serve scientists at GSFC, other NASA centers, other government agencies, and universities. The WFF mode of operation features the walk on method of conducting research projects. The principal investigator requests aircraft support by letter to WFF and after approval is granted, works with the assigned mission manager to plan all phases of project support. The instrumentation is installed in WFF electronics racks, mounted on the aircraft, the missions are flown, and the equipment is removed when the scientific objectives are met. The principal investigator reimburses WFF for each flight hours, any overtime and travel expenses generated by the project, and for other mission-related expenses such as aircraft support services required at deployment bases.

Navarro, Roger L.

Kepler Ground-Based Photometry Proof-of-Concept

We report on our efforts to evaluate the feasibility of using the 4-Shooter CCD camera on the 48-inch reflector at the Whipple Observatory to carry out a multi-band photometric survey of the Kepler target region. We also include recommendations for future work. We were assigned 36 nights with the &hooter during 2003 for this feasibility study. Most of the time during the first two dozen nights was dedicated to the development of procedures, test exposures, and a reconnaissance across the Kepler field. The final 12 nights in September and October 2003 were used for "production" observing in the middle of the Kepler field using the full complement of seven filters (SDSS u, g, r, i, z, plus our special Gred and D51 intermediate-band filters). Nine of these 12 nights were clear and photometric, and production observations were obtained at 109 pointings, corresponding to 14.6 square degrees.

Brown, Timothy M.

TurboTech Technical Evaluation Automated System

TurboTech software is a Web-based process that simplifies and semiautomates technical evaluation of NASA proposals for Contracting Officer's Technical Representatives (COTRs). At the time of this reporting, there have been no set standards or systems for training new COTRs in technical evaluations. This new process provides boilerplate text in response to interview style questions. This text is collected into a Microsoft Word document that can then be further edited to conform to specific cases. By providing technical language and a structured format, TurboTech allows the COTRs to concentrate more on the actual evaluation, and less on deciding what language would be most appropriate. Since the actual word choice is one of the more time-consuming parts of a COTRs job, this process should allow for an increase in quantity of proposals evaluated. TurboTech is applicable to composing technical evaluations of contractor proposals, task and delivery orders, change order modifications, requests for proposals, new work modifications, task assignments, as well as any changes to existing contracts.

Tiffany, Dorothy J.

Systems Engineering Leadership Development: Advancing Systems Engineering Excellence

This slide presentation reviews the Systems Engineering Leadership Development Program, with particular emphasis on the work being done in the development of systems engineers at Marshall Space Flight Center. There exists a lack of individuals with systems engineering expertise, in particular those with strong leadership capabilities, to meet the needs of the Agency's exploration agenda. Therefore there is a emphasis on developing these programs to identify and train systems engineers. The presentation reviews the proposed MSFC program that includes course work, and developmental assignments. The formal developmental programs at the other centers are briefly reviewed, including the Point of Contact (POC)

Hall, Phil

Flight Research and Validation Formerly Experimental Capabilities Supersonic Project

This slide presentation reviews the work of the Experimental Capabilities Supersonic project, that is being reorganized into Flight Research and Validation. The work of Experimental Capabilities Project in FY '09 is reviewed, and the specific centers that is assigned to do the work is given. The portfolio of the newly formed Flight Research and Validation (FRV) group is also reviewed. The various projects for FY '10 for the FRV are detailed. These projects include: Eagle Probe, Channeled Centerbody Inlet Experiment (CCIE), Supersonic Boundary layer Transition test (SBLT), Aero-elastic Test Wing-2 (ATW-2), G-V External Vision Systems (G5 XVS), Air-to-Air Schlieren (A2A), In Flight Background Oriented Schlieren (BOS), Dynamic Inertia Measurement Technique (DIM), and Advanced In-Flight IR Thermography (AIR-T).

Banks, Daniel

Determination of band oscillator strengths of atmospheric molecules from high resolution vacuum ultraviolet cross section measurements

An account is given of progress during the six month period 1/11/84 to 4/30/85 in work on: (1) rovibronic assignments of the Schumann-Runge bands of O2-18; and (2) optical depth measurements of the Schumann-Runge bands of O2-18. The work summarized above is part of a comprehensive spectroscopic investigation of the absorption wavelengths, rotational line assignments, cross sections, and band oscillator strengths of the Schumann-Runge bands of O2-18 and O-18 O-16 in the wavelength region 175-205 nm. The investigation is conducted at high resolution with a 6.65 m scanning spectrometer/spectrograph which is, by reason of its small instrumental width (FWHM = 0.0013 nm), uniquely suitable for cross section measurements of molecular bands with discrete rotational structure. Absolute cross sections, which are independent of the instrumental function and from which band oscillator strengths are directly determined, will be measured for the absorption bands that are most predissociated.

Parkinson, W. H.

A stress-based fracture model for reacting metal ejecta

The evolution of reacting metal ejecta continues to be a topic of interest at the forefront of metals in reactive and extreme environments. Ejecta are small particles formed when the surface of a metal undergoes Richtmyer–Meshkov instability from a strong shock. Experiments have shown that in the case where ejecta are in ambient conditions that induce a reaction, the ejecta behave irregularly. The ejecta temperature rises and then plateaus, and the acceleration profile shows unexpected jumps. These variations are assumed to be related to the exothermic heat release and particle mass loss caused by the reaction. To explain this phenomenon, efforts to model this in simulations have increased. While current models can capture many of these physical processes, they currently assign a constant reaction shell thickness with little physical reasoning. This work remedies this problem by assigning a dynamic physically informed shell thickness to the reacting particles, using solid analysis. The shell thickness of the particles impacts the rate of change of reacted mass in the system, as well as the rate at which the particles react. The model is based on a simple stress–strain relationship and gives a dynamic assignment for when the reacting particle should begin to fracture. We compare our model to the previous computational and simulation data to analyze the effects of different model parameters.

42 ENGINEERING

SpaceWire Protocol ID: What Does It Mean To You?

Spacewire is becoming a popular solution for satellite high-speed data buses because it is a simple standard that provides great flexibility for a wide range of system requirements. It is simple in packet format and protocol, allowing users to easily tailor their implementation for their specific application. Some of the attractive aspects of Spacewire that make it easy to implement also make it hard for future reuse. Protocol reuse is difficult because Spacewire does not have a defined mechanism to communicate with the higher layers of the protocol stack. This has forced users of Spacewire to define unique packet formats and define how these packets are to be processed. Each mission writes their own Interface Control Document (ICD) and tailors Spacewire for their specific requirements making reuse difficult. Part of the reason for this habit may be because engineers typically optimize designs for their own requirements in the absence of a standard. This is an inefficient use of project resources and costs more to develop missions. A new packet format for Spacewire has been defined as a solution for this problem. This new packet format is a compliment to the Spacewire standard that will support protocol development upon Spacewire. The new packet definition does not replace the current packet structure, i.e., does not make the standard obsolete, but merely extends the standard for those who want to develop protocols over Spacewire. The Spacewire packet is defined with the first part being the Destination Address, which may be one or more bytes. This is followed by the packet cargo, which is user defined. The cargo is truncated with an End-Of-Packet (EOP) marker. This packet structure offers low packet overhead and allows the user to define how the contents are to be formatted. It also provides for many different addressing schemes, which provide flexibility in the system. This packet flexibility is typically an attractive part of the Spacewire. The new extended packet format adds one new field to the packet that greatly enhances the capability of Spacewire. This new field called the Protocol Identifier (ID) is used to identify the packet contents and the associated processing for the packet. This feature along with the restriction in the packet format that uses the Protocol ID, allows a deterministic method of decoding packets that was not before possible. The first part of the packet is still the Destination Address, which still conforms to the original standard but with one restriction. The restriction is that the first byte seen at the destination by the user needs to be a logical address, independent of the addressing scheme used. The second field is defined as the Protocol ID, which is usually one byte in length. The packet cargo (user defined) follows the Protocol ID. After the packet cargo is the EOP, which defines the end of packet. The value of the Protocol ID is assigned by the Spacewire working group and the protocol description published for others to use. The development of Protocols for Spacewire is currently the area of greatest activity by the Spacewire working group. The first protocol definition by the working group has been completed and is now in the process of formal standardization. There are many other protocols in development for missions that have not yet received formal Protocol ID assignment, but even if the protocols are not formally assigned a value, this effort will provide synergism for future developments.

Rakow, Glenn

Action painting under spectroscopic light: Excited-state exchange interactions behind the vibrant blue in Jackson Pollock’s Number 1A, 1948

Number 1A, 1948 by Jackson Pollock is a quintessential example of his action painting technique where ropes of color, drips of black, and pools of white coalesce into the layered dynamism that defines his style. While past work has identified the red and yellow pigments that form part of his core palette, the vibrant blue in the painting has remained unassigned. In this study resonance Raman spectroscopy is used to assign the blue in the painting as manganese blue. This assignment offers critical context for the conservation of his works. Importantly, assignment of this pigment enables spectroscopic investigation of the electronic structure origin of the pure hue of manganese blue and the chemical phenomena that produce its color. To probe these phenomena, resonance Raman data are coupled to magnetic circular dichroism spectroscopy and density functional theory calculations to assign and analyze the two electronic transitions that create the blue color. This study reveals these bands are split by excited-state exchange interactions; the gap between them contains the reflected light that gives manganese blue its appearance. This sheds light on distinct advantages of molecular inorganic pigments: their ability to leverage ligand field effects in charge transfer states to create multiple intense visible absorption features and the ability to fine-tune pigment color through host lattice electrostatics.

DFT

Practical Pocket PC Application w/Biometric Security

I work in the Flight Software Engineering Branch, where we provide design and development of embedded real-time software applications for flight and supporting ground systems to support the NASA Aeronautics and Space Programs. In addition, this branch evaluates, develops and implements new technologies for embedded real-time systems, and maintains a laboratory for applications of embedded technology. The majority of microchips that are used in modern society have been programmed using embedded technology. These small chips can be found in microwaves, calculators, home security systems, cell phones and more. My assignment this summer entails working with an iPAQ HP 5500 Pocket PC. This top-of-the-line hand-held device is one of the first mobile PC's to introduce biometric security capabilities. Biometric security, in this case a fingerprint authentication system, is on the edge of technology as far as securing information. The benefits of fingerprint authentication are enormous. The most significant of them are that it is extremely difficult to reproduce someone else's fingerprint, and it is equally difficult to lose or forget your own fingerprint as opposed to a password or pin number. One of my goals for this summer is to integrate this technology with another Pocket PC application. The second task for the summer is to develop a simple application that provides an Astronaut EVA (Extravehicular Activity) Log Book capability. The Astronaut EVA Log Book is what an astronaut would use to report the status of field missions, crew physical health, successes, future plans, etc. My goal is to develop a user interface into which these data fields can be entered and stored. The applications that I am developing are created using eMbedded Visual C++ 4.0 with the Pocket PC 2003 Software Development Kit provided by Microsoft.

Logan, Julian

Concurrent Path Planning with One or More Humanoid Robots

A robotic system includes a controller and one or more robots each having a plurality of robotic joints. Each of the robotic joints is independently controllable to thereby execute a cooperative work task having at least one task execution fork, leading to multiple independent subtasks. The controller coordinates motion of the robot(s) during execution of the cooperative work task. The controller groups the robotic joints into task-specific robotic subsystems, and synchronizes motion of different subsystems during execution of the various subtasks of the cooperative work task. A method for executing the cooperative work task using the robotic system includes automatically grouping the robotic joints into task-specific subsystems, and assigning subtasks of the cooperative work task to the subsystems upon reaching a task execution fork. The method further includes coordinating execution of the subtasks after reaching the task execution fork.

Sanders, Adam M.

Evidence for an isomeric {pi}½{sup +}[411] state in {sup 183}Ta

We report on the identification of a new isomeric state in Ta populated via the ground-state -decay of Hf. The experiment was performed at the KISS setup at RIKEN, where neutron-rich hafnium isotopes were produced via multi-nucleon transfer (MNT) reactions, followed by laser ionization of hafnium atoms, mass separation, and detection using an electron-gamma coincidence system. Isomeric spectroscopy was carried out by gating on different electron-gamma time correlations. A 459.1 keV -ray transition was identified in delayed spectra, and a half-life of μ was extracted through time-distribution fitting. The 459.1 keV state in Ta is known from previous work and has been assigned a Nilsson orbital configuration of , while a proposed new isomeric state above it is interpreted as a configuration that decays to via a low-energy, unobserved E2 transition. This is consistent with the systematic trends in neighbouring odd-A nuclei and transition rate calculations. Similar content being viewed by others

Doshi, S.

The vacuum ultraviolet spectra of HCN, C2N2, and CH3CN

Quantitative vacuum ultraviolet absorption spectra for HCN, C2N2, and CH3CN have been obtained over the wavelength range 60-160 nm. Where comparison is possible, the measurements of the absorption coefficients for HCN and C2N2 are consistent with previous studies. Because of the superior resolution of this work (0.05 nm), vibrational assignments in the valence and Rydberg transitions of HCN have been extended while higher members of the Rydberg series in CH3CN have been identified.

Nuth, J. A.