Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “Active target”

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 523 records · Page 29
All sourcesNASA NTRSDOE OSTI
NASA NTRS2016

Effects of Simulated Spaceflight on Mitochondrial Oxidative Stress in Bone Remodelling

Microgravity and ionizing radiation may contribute to cellular stress; resulting in increased generation of reactive oxygen species (ROS), DNA damage, cell cycle arrest, and cell death. We hypothesized that suppression of excess ROS in osteoblasts and osteoclasts will improve bone microarchitecture. To test our hypothesis, we used irradiated transgenic mCAT mice overexpressing human anti-oxidant catalase gene targeted to the mitochondria (main site for ROS production). mCAT mice expressed the transgene and displayed elevated catalase activity in bone and ex vivo osteoblast and osteoclast cultures. Treated bone from wildtype mice showed elevated levels of oxidative damage whereas mCAT mice did not. Also, increased catalase activity correlated with decreased MDA levels and that increased oxidative damage correlated with decreased % bone volume. Ex-vivo osteoblast colony growth positively correlated with osteoblast catalase activity. mCAT mice displayed reduced % bone volume. Treatment caused significant bone loss in wildtype mice. Treatment also caused slight deficits in microarchitecture of mCAT mice. In conclusion, ROS signaling in both osteoblast and osteoclast lineage cells contribute to skeletal development and remodeling and quenching oxidative damage could play a role in bone loss prevention.

bone loss↗
NASA NTRSDate not supplied

MAGIC Mission Science and Applications Related to Cryosphere, Solid Earth and Neutral Atmosphere

The GRACE and GFO missions have revolutionised our understanding of mass movement at and below the surface of the Earth but they, nonetheless, have restrictions related to spatial and temporal resolution and instrument sensitivity that limits our ability to resolve certain processes. In this presentation we focus on the advances and capabilities that the proposed Mass change And Geosciences International Constellation (MAGIC) mission will deliver for cryosphere and solid Earth applications and will also consider the potential it will have for studying the neutral atmosphere. The time-varying gravity missions to date have had an effective spatial resolution of ~300 km, which is larger than the scale of any glacier or ice caps and larger than most catchments on the Greenland Ice Sheet. Even over Antarctica, the limited spatial resolution is a major limitation for regions such as the Antarctic Peninsula. Tectonic process, such as Earthquakes, volcanic activity and even viscous mantle flow can take place on scales smaller than can be resolved currently. The target resolution and accuracy for MAGIC over ice is 170 km at 2.6 mm/yr EWH over the long term and 250 km at 5.5 mm EWH at monthly resolution plus lower accuracy daily to weekly capabilities. We consider here what this means for understanding and observing ice mass exchange with the oceans and improving our ability to measure the manometric contribution to sea level rise. Based on similar targets, we also explore the improvements this offers for monitoring different types of solid Earth processes including geohazards, crustal evolution and deep interior properties and dynamics. We also consider what contributions MAGIC will be able to make to observations of thermosphere neutral density and related atmospheric parameters.

Jonathan Bamber↗
NASA NTRS2004

[Activities of System Studies and Simulation, Inc.]

Contents include the following: 1. Launch Vehicle Interface Work Performed: a. S3 provided to KSC the new launch inclination targets needed for the April '04 launch date. 2. Prelaunch operations work performed: a. S3 updated the staffing plan for MSFC on-console personnel\during the Final Countdown prior to launch. 3. Software Assessment Work Performed: a. S3 evaluated and recommended approval for Program Control Board (PCB) proposed change 649 for ground software changes, as well as change 650 and 650A for Stored Program Commands. 4. Education and Public Outreach Work Performed: a. S3 continues to coordinate the effort for the design and fabrication of scale models of the GP-3 for use at the launch site, education forums, and management/technical briefings. S3 also prepared a Change Request for additional funds needed for fabrication of additional scale models. S3 drafted the planned uses of these models, including the possibility of participation in the Boston, MA showings of the traveling Einstein Exhibit. 5. Program Management Support Work Performed: a. S3 prepared the input for and closed three MSFC Centerwide Action Item Tracking Systems (CAITS) actions during this period.

Source record↗
NASA NTRS2005

Towards the Verification of Human-Robot Teams

Human-Agent collaboration is increasingly important. Not only do high-profile activities such as NASA missions to Mars intend to employ such teams, but our everyday activities involving interaction with computational devices falls into this category. In many of these scenarios, we are expected to trust that the agents will do what we expect and that the agents and humans will work together as expected. But how can we be sure? In this paper, we bring together previous work on the verification of multi-agent systems with work on the modelling of human-agent teamwork. Specifically, we target human-robot teamwork. This paper provides an outline of the way we are using formal verification techniques in order to analyse such collaborative activities. A particular application is the analysis of human-robot teams intended for use in future space exploration.

Fisher, Michael↗
NASA NTRS2023

Results from InSight Robotic Arm Activities

The InSight lander carried an Instrument Deployment System (IDS) that included an Instrument Deployment Arm (IDA), scoop, five finger “claw” grapple, forearm-mounted Instrument Deployment Camera (IDC) requiring arm motion to image a target, and landermounted Instrument Context Camera (ICC), designed to image the workspace, and to place the instruments onto the surface. As originally proposed, the IDS included a previously built arm and flight spare black and white cameras and had no science objectives or requirements, or expectation to be used after instrument deployment (90 sols). During project development the detectors were upgraded to color, and it was recognized that the arm could be used to carry out a wide variety of activities that would enable both geology and physical properties investigations. During surface operations for two martian years, the IDA was used during major campaigns to image the surface around the lander, to deploy the instruments, to assist the mole in penetrating beneath the surface, to bury a portion of the seismometer tether, to clean dust from the solar arrays to increase power, and to conduct a surface geology investigation including soil mechanics and physical properties experiments. No other surface mission has engaged in such a sustained and varied campaign of arm and scoop activities directed at such a diverse suite of objectives. Images close to the surface and continuous meteorology measurements provided important constraints on the threshold friction wind speed needed to initiate aeolian saltation and surface creep. The IDA was used extensively for almost 22 months to assist the mole in penetrating into the subsurface. Soil was scraped into piles and dumped onto the seismometer tether six times in an attempt to bury the tether and ∼ 30% was entrained in the wind and dispersed downwind 1-2 m, darkening the surface. Seven solar array cleaning experiments were conducted by dumping scoops of soil from 35 cm above the lander deck during periods of high wind that dispersed the sand onto the panels that kicked dust off of the panels into suspension in the atmosphere, thereby increasing the power by ∼15% during this period. Final IDA activities included an indentation experiment that used the IDA scoop to push on the ground to measure the plastic deformation of the soil that complemented soil mechanics measurements from scoop interactions with the surface, and two experiments in which SEIS measured the tilt from the arm pressing on the ground to derive near surface elastic properties.

Mars↗
NASA NTRS2017

NASA's Advanced Exploration Systems Mars Transit Habitat Refinement Point of Departure Design

This paper describes the recently developed point of departure design for a long duration, reusable Mars Transit Habitat, which was established during a 2016 NASA habitat design refinement activity supporting the definition of NASA's Evolvable Mars Campaign. As part of its development of sustainable human Mars mission concepts achievable in the 2030s, the Evolvable Mars Campaign has identified desired durations and mass/dimensional limits for long duration Mars habitat designs to enable the currently assumed solar electric and chemical transportation architectures. The Advanced Exploration Systems Mars Transit Habitat Refinement Activity brought together habitat subsystem design expertise from across NASA to develop an increased fidelity, consensus design for a transit habitat within these constraints. The resulting design and data (including a mass equipment list) contained in this paper are intended to help teams across the agency and potential commercial, academic, or international partners understand: 1) the current architecture/habitat guidelines and assumptions, 2) performance targets of such a habitat (particularly in mass, volume, and power), 3) the driving technology/capability developments and architectural solutions which are necessary for achieving these targets, and 4) mass reduction opportunities and research/design needs to inform the development of future research and proposals. Data presented includes: an overview of the habitat refinement activity including motivation and process when informative; full documentation of the baseline design guidelines and assumptions; detailed mass and volume breakdowns; a moderately detailed concept of operations; a preliminary interior layout design with rationale; a list of the required capabilities necessary to enable the desired mass; and identification of any worthwhile trades/analyses which could inform future habitat design efforts. As a whole, the data in the paper show that a transit habitat meeting the 43 metric tons launch mass/trans-Mars injection burn limits specified by the Evolvable Mars Campaign is achievable near the desired timeframe with moderate strategic investments including maintainable life support systems, repurposable structures and packaging, and lightweight exercise modalities. It also identifies operational and technological options to reduce this mass to less than 41 metric tons including staging of launch structure/packaging and alternate structural materials.

Simon, Matthew↗
NASA NTRS2011

Improving Lunar Exploration with Robotic Follow-up

We are investigating how augmenting human field work with subsequent robot activity can improve lunar exploration. Robotic "follow-up" might involve: completing geology observations; making tedious or long-duration measurements of a target site or feature; curating samples in-situ; and performing unskilled, labor-intensive work. To study this technique, we have begun conducting a series of lunar analog field tests at Haughton Crater (Canada). Motivation: In most field geology studies on Earth, explorers often find themselves left with a set of observations they would have liked to make, or samples they would have liked to take, if only they had been able to stay longer in the field. For planetary field geology, we can imagine mobile robots - perhaps teleoperated vehicles previously used for manned exploration or dedicated planetary rovers - being deployed to perform such follow-up activities [1].

Fong, T.↗
NASA NTRS1989

Spectral calibration analysis of the airborne oceanographic lidar

Efforts were concentrated on the spectral resolution of the Airborne Oceanographic Lidar (AOL). This year's work was targeted towards the analysis of calibration techniques to enable the AOL to measure absolute radiances of both passive and active modes of operation. Absolute spectral calibration of the AOL is necessary in order to fully understand and monitor the sensitivity and stability of the total system. Calibration is also needed to obtain valid surface truth data, with which to improve the accuracy of satellite-borne oceanic color scanners. In particular, accurate measurements of oceanic chlorophyll concentrations rests upon reliable irradiance calibrations of both laser induced and solar induced chlorophyll fluoresence. An analysis was performed on the spectral calibration methods used by the AOL. The optical path of the instrumentation was examined to study how the radiance from a calibration sphere was influenced. Ray tracing analysis was performed, including the Cassegrain-telescope optics. It was determined that the calibration radiance was significantly effected by optical-defocusing, due to close positioning of the calibration sphere with respect to the telescope. Since the multi-mode usages of the AOL require varying altitudes and trajectories, a computational algorithm was developed to compensate for image distortions of the telescope optics. Secondary mirror blockage, secondary vignetting, and beam divergence was determined, in order to account for the actual amount of calibrated flux received at the spectral sensors.

Rousey, Carlton E.↗
NASA NTRS1991

The hydrogen technology assessment, phase 1

The purpose of this phase 1 report is to begin to form the information base of the economics and energy uses of hydrogen-related technologies on which the members of the National Hydrogen Association (NHA) can build a hydrogen vision of the future. The secondary goal of this report is the development of NHA positions on national research, development, and demonstration opportunities. The third goal, with the aid of the established hydrogen vision and NHA positions, is to evaluate ongoing federal research goals and activities. The evaluations will be performed in a manner that compares the costs associated with using systems that achieve those goals against the cost of performing those tasks today with fossil fuels. From this ongoing activity should emerge an NHA information base, one or more hydrogen visions of the future, and cost and performance targets for hydrogen applications to complete in the market place.

Bain, Addison↗
NASA NTRS1992

The gas production rate of periodic comet d'Arrest

Comet P/d'Arrest is a potential target for a rendezvous mission to a short period comet. Its light curve is rather peculiar, the comet being active only after perihelion passage. One apparition out of two is easy to observe from the ground. The 1995 apparition of the comet will offer a unique opportunity to characterize the outgassing properties of its nucleus.

Festou, Michel C.↗
NASA NTRS1991

Rendezvous radar for the orbital maneuvering vehicle

The Rendezvous Radar Set (RRS) was designed at Motorola's Strategic Electronics Division in Chandler, Arizona, to be a key subsystem aboard NASA's Orbital Maneuvering Vehicle (OMV). The unmanned OMV, which was under development at TRW's Federal Systems Division in Redondo Beach, California, was designed to supplement the Shuttle's satellite delivery, retrieval, and maneuvering activities. The RRS was to be used to locate and then provide the OMV with vectoring information to the target satellite (or Shuttle or Space Station) to aid the OMV in making a minimum fuel consumption approach and rendezvous. The OMV development program was halted by NASA in 1990 just as parts were being ordered for the RRS engineering model. The paper presented describes the RRS design and then discusses new technologies, either under development or planned for development at Motorola, that can be applied to radar or alternative sensor solutions for the Automated Rendezvous and Capture problem.

Locke, John W.↗
NASA NTRS1993

Quantitative EEG patterns of differential in-flight workload

Four test pilots were instrumented for in-flight EEG recordings using a custom portable recording system. Each flew six, two minute tracking tasks in the Calspan NT-33 experimental trainer at Edwards AFB. With the canopy blacked out, pilots used a HUD display to chase a simulated aircraft through a random flight course. Three configurations of flight controls altered the flight characteristics to achieve low, moderate, and high workload, as determined by normative Cooper-Harper ratings. The test protocol was administered by a command pilot in the back seat. Corresponding EEG and tracking data were compared off-line. Tracking performance was measured as deviation from the target aircraft and combined with control difficulty to achieve an estimate of 'cognitive workload'. Trended patterns of parietal EEG activity at 8-12 Hz were sorted according to this classification. In all cases, high workload produced a significantly greater suppression of 8-12 Hz activity than low workload. Further, a clear differentiation of EEG trend patterns was obtained in 80 percent of the cases. High workload produced a sustained suppression of 8-12 Hz activity, while moderate workload resulted in an initial suppression followed by a gradual increment. Low workload was associated with a modulated pattern lacking any periods of marked or sustained suppression. These findings suggest that quantitative analysis of appropriate EEG measures may provide an objective and reliable in-flight index of cognitive effort that could facilitate workload assessment.

Sterman, M. B.↗
NASA NTRS1993

Preliminary analysis of the JAPE ground vehicle test data with an artificial neural network classifier

Remotely sensing and classifying military vehicles in a battlefield environment have been the source of much research over the past 20 years. The ability to know where threat vehicles are located is an obvious advantage to military personnel. In the past active methods of ground vehicle detection such as radar have been used, but with the advancement of technology to locate these active sensors, passive sensors are preferred. Passive sensors detect acoustic emissions, seismic movement, electromagnetic radiation, etc., produced by the target and use this information to describe it. Deriving the mathematical models to classify vehicles in this manner has been, and is, quite complex and not always reliable. However, with the resurgence of artificial neural network (ANN) research in the past few years, developing models for this work may be a thing of the past. Preliminary results from an ANN analysis to the tank signatures recorded at the Joint Acoustic Propagation Experiment (JAPE) at the US Army White Sands Missile Range, NM, in July 1991, are presented.

Larsen, Nathan F.↗
NASA NTRS2001

ATIC Flight Data Processing

The first flight of the Advanced Thin Ionization Calorimeter (ATIC) experiment from McMurdo, Antarctica lasted for 16 days, starting in December, 2000. The ATIC instrument consists of a fully active 320-crystal, 960-channel Bismuth Germanate (BGO) calorimeter, 202 scintillator strips in 3 hodoscopes interleaved with a graphite target, and a 4480-pixel silicon matrix charge detector. We have developed an Object Oriented data processing package based on ROOT. In this paper, we will describe the data processing scheme used in handling the accumulated 45 GB of flight data. We will also discuss trigger issues by comparing the measured energy-dependent trigger efficiency with its simulation and calibration issues by considering the time-dependence of housekeeping information, etc.

Ahn, H. S.↗
NASA NTRS2004

"Chiron": A Proposed Remote Sensing Prompt Gamma Ray Activation Analysis Instrument for a Nuclear Powered Prometheus Mission

Prompt Gamma Ray Activation Analysis (PGAA) from neutron capture is an important experimental method that yields information on the elemental abundance of target materials. Gamma ray analysis has been used in planetary exploration missions by taking advantage of the production of neutrons as a result of Galactic Cosmic Ray interaction within the planetary surfaces. The .gamma ray signal that can be obtained from the GCR production of neutrons is very low, so we seek a superior neutron source. NASA s Project Prometheus and the Dept. of Energy aim to develop a nuclear power system for planetary exploration. This provides us with a tremendous opportunity to harness the reactor as a source of neutrons that can be used for PGAA. We envision a narrow stream of neutrons from the reactor directed toward the surface of an asteroid or comet producing the prompt gamma ray signal for analysis. Under ideal conditions of neutron flux and spacecraft orbit, both the signal strength and the spatial resolution will improved by several orders of magnitude over previously missions.

Floyd, Samuel R.↗
NASA NTRS2009

Stellar Imager - Observing the Universe in High Definition

Stellar Imager (SI) is a space-based, UV Optical Interferometer (UVOI) with over 200x the resolution of HST. It will enable 0.1 milli-arcsec spectral imaging of stellar surfaces and the Universe in general and open an enormous new 'discovery space' for Astrophysics with its combination of high angular resolution, dynamic imaging, and spectral energy resolution. SI's goal is to study the role of magnetism in the Universe and revolutionize our understanding of: 1) Solar/Stellar Magnetic Activity and their impact on Space Weather, Planetary Climates. and Life, 2) Magnetic and Accretion Processes and their roles in the Origin and Evolution of Structure and in the Transport of Matter throughout the Universe, 3) the close-in structure of Active Galactic Nuclei and their winds, and 4) Exo-Solar Planet Transits and Disks. The SI mission is targeted for the mid 2020's - thus significant technology development in the upcoming decade is critical to enabling it and future spacebased sparse aperture telescope and distributed spacecraft missions. The key technology needs include: 1) precision formation flying of many spacecraft, 2) precision metrology over km-scales, 3) closed-loop control of many-element, sparse optical arrays, 4) staged-control systems with very high dynamic ranges (nm to km-scale). It is critical that the importance of timely development of these capabilities is called out in the upcoming Astrophysics and Heliophysics Decadal Surveys, to enable the flight of such missions in the following decade. S1 is a 'Landmark/Discovery Mission' in 2005 Heliophysics Roadmap and a candidate UVOI in the 2006 Astrophysics Strategic Plan. It is a NASA Vision Mission ('NASA Space Science Vision Missions' (2008), ed. M. Allen) and has also been recommended for further study in the 2008 NRC interim report on missions potentially enabled enhanced by an Ares V' launch, although a incrementally-deployed version could be launched using smaller rockets.

Carpenter, Kenneth↗
NASA NTRS2009

NASA Exercise Physiology and Countermeasures Project Overview

Efficient exercise countermeasures are necessary to offset or minimize spaceflight-induced deconditioning and to maximize crew performance of mission tasks. These countermeasure protocols should use the fewest crew and vehicle resources. NASA s Exercise Physiology and Countermeasures (ExPC) Project works to identify, collect, interpret, and summarize evidence that results in effective exercise countermeasure protocols which protect crew health and performance during International Space Station (ISS) and future exploration-class missions. The ExPC and NASA s Human Research Program are sponsoring multiple studies to evaluate and improve the efficacy of spaceflight exercise countermeasures. First, the Project will measure maximal aerobic capacity (VO2max) during cycle ergometry before, during, and after ISS missions. Second, the Project is sponsoring an evaluation of a new prototype harness that offers improved comfort and increased loading during treadmill operations. Third, the Functional Tasks Test protocol will map performance of anticipated lunar mission tasks with physiologic systems before and after short and long-duration spaceflight, to target system contributions and the tailoring of exercise protocols to maximize performance. In addition to these studies that are actively enrolling crewmember participants, the ExPC is planning new studies that include an evaluation of a higher-intensity/lower-volume exercise countermeasure protocol aboard the ISS using the Advanced Resistive Exercise Device and second-generation treadmill, studies that evaluate bone loading during spaceflight exercise, and ground-based studies that focus on fitness for duty standards required to complete lunar mission tasks and for which exercise protocols need to protect. Summaries of these current and future studies and strategies will be provided to international colleagues for knowledge sharing and possible collaboration.

Loerch, Linda↗
NASA NTRS2018

An Introduction to SPEARS (Spectrum Education Awareness)

This presentation provides an overview of the SPectrum Education AwaRenesS (SPEARS) initiative developed by the NASA Spectrum Office under HEO/SCaN. SPEARS is a strategic initiative that is comprised of fourteen (14) activities/tasks targeted for various stakeholders within and external to NASA and from the spectrum and non-spectrum communities. These activities will also facilitate fostering partnerships and enhance the regulatory and policy understanding with international spectrum regulators and other space agencies. Further, SPEARS will institute several activities geared to promote spectrum management and to gain the interest of the next and future generations of spectrum managers, through Science, Technology, Engineering, and Mathematics (STEM) outreach.

spectrum training↗