Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “Remote Work”

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 1,099 records · Page 61
All sourcesNASA NTRSDOE OSTI
NASA NTRS2015

Implementing NASA's Capability-Driven Approach: Insight into NASA's Processes for Maturing Exploration Systems

NASA is engaged in transforming human spaceflight. The Agency is shifting from an exploration-based program with human activities focused on low Earth orbit (LEO) and targeted robotic missions in deep space to a more sustainable and integrated pioneering approach. Through pioneering, NASA seeks to address national goals to develop the capacity for people to work, learn, operate, live, and thrive safely beyond the Earth for extended periods of time. However, pioneering space involves more than the daunting technical challenges of transportation, maintaining health, and enabling crew productivity for long durations in remote, hostile, and alien environments. This shift also requires a change in operating processes for NASA. The Agency can no longer afford to engineer systems for specific missions and destinations and instead must focus on common capabilities that enable a range of destinations and missions. NASA has codified a capability driven approach, which provides flexible guidance for the development and maturation of common capabilities necessary for human pioneers beyond LEO. This approach has been included in NASA policy and is captured in the Agency's strategic goals. It is currently being implemented across NASA's centers and programs. Throughout 2014, NASA engaged in an Agency-wide process to define and refine exploration-related capabilities and associated gaps, focusing only on those that are critical for human exploration beyond LEO. NASA identified 12 common capabilities ranging from Environmental Control and Life Support Systems to Robotics, and established Agency-wide teams or working groups comprised of subject matter experts that are responsible for the maturation of these exploration capabilities. These teams, called the System Maturation Teams (SMTs) help formulate, guide and resolve performance gaps associated with the identified exploration capabilities. The SMTs are defining performance parameters and goals for each of the 12 capabilities, developing maturation plans and roadmaps for the identified performance gaps, specifying the interfaces between the various capabilities, and ensuring that the capabilities mature and integrate to enable future pioneering missions. By managing system development through the SMTs instead of traditional NASA programs and projects, the Agency is shifting from mission-driven development to a more flexible, capability-driven development. The process NASA uses to establish, integrate, prioritize, and manage the SMTs and associated capabilities is iterative. NASA relies on the Human Exploration and Operation Mission Directorate's SMT Integration Team within Advanced Exploration Systems to coordinate and facilitate the SMT process. The SMT Integration team conducts regular reviews and coordination meetings among the SMTs and has developed a number of tools to help the Agency implement capability driven processes. The SMT Integration team is uniquely positioned to help the Agency coordinate the SMTs and other processes that are making the capability-driven approach a reality. This paper will introduce the SMTs and the 12 key capabilities they represent. The role of the SMTs will be discussed with respect to Agency-wide processes to shift from mission-focused exploration to a capability-driven pioneering approach. Specific examples will be given to highlight systems development and testing within the SMTs. These examples will also show how NASA is using current investments in the International Space Station and future investments to develop and demonstrate capabilities. The paper will conclude by describing next steps and a process for soliciting feedback from the space exploration community to refine NASA's process for developing common exploration capabilities.

Williams-Byrd, Julie↗
NASA NTRS2012

Ventilator Technologies Sustain Critically Injured Patients

Consider this scenario: A soldier has been critically wounded in a sudden firefight in a remote region of Afghanistan. The soldier s comrades attend to him and radio for help, but the soldier needs immediate medical expertise and treatment that is currently miles away. The connection between medical support for soldiers on the battlefield and astronauts in space may not be immediately obvious. But when it comes to providing adequate critical care, NASA and the military have very similar operational challenges, says Shannon Melton of NASA contractor Wyle Integrated Science and Engineering. Melton works within Johnson Space Center s Space Medicine Division, which supports astronaut crew health before, during, and after flight. In space, we have a limited number of care providers, and those providers are not always clinicians with extensive medical training. We have limited room to provide care, limited consumables, and our environment is not like that of a hospital, she says. The Space Medicine Division s Advanced Projects Group works on combining the expertise of both clinicians and engineers to develop new capabilities that address the challenges of medical support in space, including providing care to distant patients. This field, called telemedicine, blends advanced communications practices and technologies with innovative medical devices and techniques to allow caregivers with limited or no medical experience to support a patient s needs. NASA, just by its nature, has been doing remote medicine since the beginning of the Space Program, says Melton, an engineer in the Advanced Projects Group. Since part of NASA s mandate is to transfer the results of its technological innovation for the benefit of the public, the Agency has worked with doctors and private industry to find ways to apply the benefits of space medicine on Earth. In one such case, a NASA partnership has resulted in new technologies that may improve the quality of emergency medicine for wounded soldiers on the battlefield and regular civilians.

Source record↗
NASA NTRS2011

Robonaut 2 - Initial Activities On-Board the ISS

Robonaut 2, or R2, arrived on the International Space Station in February 2011 and is currently undergoing testing in preparation for it to become, initially, an Intra-Vehicular Activity (IVA) tool and then evolve into a system that can perform Extra-Vehicular Activities (EVA). After the completion of a series of system level checks to ensure that the robot traveled well on-board the Space Shuttle Atlantis, ground control personnel will remotely control the robot to perform free space tasks that will help characterize the differences between earth and zero-g control. For approximately one year, the fixed base R2 will perform a variety of experiments using a reconfigurable task board that was launched with the robot. While working side-by-side with human astronauts, Robonaut 2 will actuate switches, use standard tools, and manipulate Space Station interfaces, soft goods and cables. The results of these experiments will demonstrate the wide range of tasks a dexterous humanoid can perform in space and they will help refine the methodologies used to control dexterous robots both in space and here on earth. After the trial period that will evaluate R2 while on a fixed stanchion in the US Laboratory module, NASA plans to launch climbing legs that when attached to the current on-orbit R2 upper body will give the robot the ability to traverse through the Space Station and start assisting crew with general IVA maintenance activities. Multiple control modes will be evaluated in this extra-ordinary ISS test environment to prepare the robot for use during EVAs. Ground Controllers will remotely supervise the robot as it executes semi-autonomous scripts for climbing through the Space Station and interacting with IVA interfaces. IVA crew will locally supervise the robot using the same scripts and also teleoperate the robot to simulate scenarios with the robot working alone or as an assistant during space walks.

Diftler, M. A.↗
NASA NTRSDate not supplied

EVA Planning: Using Neutral Buoyancy Laboratory (NBL) Training to Predict in-Flight Energy Expenditure

Metabolic rate (“met rate”) is the amount of energy expended over a period of time and is influenced by many factors including body composition, level of physical activity, resting metabolic rate, sex, age, and food intake. Met rate is measured during Extravehicular Activity (EVA) training at the Neutral Buoyancy Laboratory (NBL) and during in-flight EVAs through indirect calorimetry, calculating energy expenditure from respiratory measurements of O 2 consumption and/or CO 2 production. During Extravehicular Activity (EVA) planning, metabolic cost is important to consider and is used to inform EVA duration based on spacesuit consumables associated with life support systems. Currently, NBL and previous ISS EVA met rate data for specified crewmembers are utilized to predict in-flight EVA metabolic costs based on a proposed EVA timeline. Timeline data collected during training is used to relate met rates to specific EVA activities, which are in turn assigned to more generalized EVA task categories, categorizing by both task type and restraint type. EVA task categories include EVA Setup/Cleanup, Worksite Setup/Cleanup, Cable Routing, Bolts, Fluid Connectors, Electrical Connectors, R&R Work, Miscellaneous Work, Incapacitated Crew Rescue (being rescued or performing), Assisted Crew Rescue (being assisted or performing), and Translation. Restraint types consist of Free-Float, Body Restraint Tether (BRT), Articulating Portable Foot Restraint (APFR), and Space Station Remote Manipulator System (SSRMS). From a crewmember’s historical data, individualized 10th, 50th and 90th percentile met rate estimates are generated for each task category and used to estimate the proposed EVA timeline metabolic cost. In-flight metabolic data (“As-Executed”) from recent ISS US EVAs 85-88 (totaling eight EVA crewmember met rates) was compared with their predicted metabolic cost (“As-Planned”) to evaluate the accuracy of the current met rate estimation method. Across the four EVAs, As-Executed Cumulative EVA Total Metabolic Cost (M = 5893.78 BTU, SD = 816.60) was not significantly different compared to As-Planned Cumulative EVA Total Metabolic Cost (M = 6106.60 BTU, SD = 826.62; t(7) = 0.751 , p = .477). Though not a significant difference, generally, As-Planned total estimates were slightly higher than As-Executed total metabolic cost. Relative Error for Cumulative EVA Total Metabolic Cost ranged from -33% to 14.7%, depending on the crewmember and EVA. When comparing As-Planned to A-Executed EVA task categories for Bolts, Electrical Connectors, EVA Cleanup, EVA Setup, Miscellaneous Work, Translation, Worksite Cleanup, and Worksite Setup during these EVAs, no significant differences were observed, however, there was a significant difference in As-Planned (M = 783.71 BTU, SD = 408.88) compared to As-Executed (M = 608.87 BTU, SD = 425.29) metabolic cost for the task category of Repair-and-Replace (R&R) Work (t(17) = 3.21 , p = .005). Looking closer within the R&R Work task category, As-Executed R&R Work with Free-Float restraint type (M = 706.17 BTU, SD = 352.18) was significantly less than As-Planned R&R Work with Free-Float restraint type (M= 887.96 BTU, SD = 381.42; t(12) = 2.59, p < .024). As-Executed R&R Work with SSRMS Restraint type (M = 355.89 BTU, SD = 534.65) was not significantly different from As-Planned values (M = 512.69 BTU, SD = 383.34; t(4) = 1.88, p = 0.132). These findings suggest that the energy expended performing R&R Work (Free-Float) is lower in flight than predicted. Accurate predictions of the metabolic cost of EVA are essential for planning and executing successful ISS EVAs. Overall, the current met rate prediction method is similar to actual in-flight values, slightly erring on the side of overestimation. Future work includes analysis of more historical in-flight EVA data to increase the power of the analysis, evaluating the NBL-ISS met rate conversion factor between NBL and ISS tasks, as well as exploring methods of substitution when crewmembers are missing prior task category data.

Lauren Cox↗
DOE OSTI2021

Regional Relative Risk, a Physics-Based Metric for Characterizing Airborne Infectious Disease Transmission

Airborne infectious disease transmission events occur over a wide range of spatial scales and can be an important means of disease transmission. Physics- and biology-based models can assist in predicting airborne transmission events, overall disease incidence, and disease control strategy efficacy. We describe a new theory that extends current approaches for the case in which an individual is infected by a single airborne particle, including the scenario in which numerous infectious particles are present in the air but only one causes infection. A single infectious particle can contain more than one pathogenic microorganism and be physically larger than the pathogen itself. This approach allows robust relative risk estimates even when there is wide variation in (i) individual exposures and (ii) the individual response to that exposure (the pathogen dose-response function can take any mathematical form and vary by individual). Based on this theory, we propose the regional relative risk—a new metric, distinct from the traditional relative risk metric, that compares the risk between two regions. In theory, these regions can range from individual rooms to large geographic areas. In this paper, we apply the regional relative risk metric to outdoor disease transmission events over spatial scales ranging from 50 m to 20 km, demonstrating that in many common cases minimal input information is required to use the metric. Also, we demonstrate that the model predictions are consistent with data from prior outbreaks. Future efforts could apply and validate this theory for other spatial scales, such as transmission within indoor environments. This work provides context for (i) the initial stages of an airborne disease outbreak and (ii) larger-scale disease spread, including unexpected low-probability disease “sparks” that potentially affect remote populations, a key practical issue in controlling airborne disease outbreaks.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

Development of self-sensing materials for extreme environments based on metamaterial concept and additive manufacturing

Structural health monitoring of an engineered component in a harsh environment is critical for multiple DOE missions including nuclear fuel cycle, subsurface energy production/storage, and energy conversion. Supported by a seeding Laboratory Directed Research & Development (LDRD) project, we have explored a new concept for structural health monitoring by introducing a self-sensing capability into structural components. The concept is based on two recent technological advances: metamaterials and additive manufacturing. A self-sensing capability can be engineered by embedding a metastructure, for example, a sheet of electromagnetic resonators, either metallic or dielectric, into a material component. This embedment can now be realized using 3-D printing. The precise geometry of the embedded metastructure determines how the material interacts with an incident electromagnetic wave. Any change in the structure of the material (e.g., straining, degradation, etc.) would inevitably perturbate the embedded metastructures or metasurface array and therefore alter the electromagnetic response of the material, thus resulting in a frequency shift of a reflection spectrum that can be detected passively and remotely. This new sensing approach eliminates complicated environmental shielding, in-situ power supply, and wire routing that are generally required by the existing active-circuit-based sensors. The work documented in this report has preliminarily demonstrated the feasibility of the proposed concept. The work has established the needed simulation tools and experimental capabilities for future studies.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Generalized Quantum Convolution for Multidimensional Data

The convolution operation plays a vital role in a wide range of critical algorithms across various domains, such as digital image processing, convolutional neural networks, and quantum machine learning. In existing implementations, particularly in quantum neural networks, convolution operations are usually approximated by the application of filters with data strides that are equal to the filter window sizes. One challenge with these implementations is preserving the spatial and temporal localities of the input features, specifically for data with higher dimensions. In addition, the deep circuits required to perform quantum convolution with a unity stride, especially for multidimensional data, increase the risk of violating decoherence constraints. In this work, we propose depth-optimized circuits for performing generalized multidimensional quantum convolution operations with unity stride targeting applications that process data with high dimensions, such as hyperspectral imagery and remote sensing. We experimentally evaluate and demonstrate the applicability of the proposed techniques by using real-world, high-resolution, multidimensional image data on a state-of-the-art quantum simulator from IBM Quantum.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
NASA NTRS1982

The intercrater plains of Mercury and the Moon: Their nature, origin and role in terrestrial planet evolution. Discussion of the nature, origin and role of the intercrater plains of Mercury and the Moon

The nature and origin of the intercrater plains of Mercury and the Moon as determined through geologic mapping, crater statistics, and remotely sensed data are summarized. Implications of these results regarding scarp formation, absolute ages, and terrestrial planet surfaces are included. The role of the intercrater plains is defined and future work which might lead to a better understanding of these units and terrestrial planet evolution is outlined.

Leake, M. A.↗
NASA NTRS1985

NAS - Supercomputing master tool for aeronautics

Features, performance objectives and applications planned for the NASA National Aerodynamics Simulator (NAS) are outlined. NAS was conceived in the 1970s as a means to performing numerical aerodynamic simulations beyond the scope of wind tunnel testing for high-speed flight. Present supercomputers cannot deal with problems exhibiting strongly coupled viscous effects, which are being increasingly more accurately represented by approximations to the full Navier-Stokes equations. Located at the NASA-Ames Center, the NAS will by 1990 comprise a distributed computer network capable of a 4 Gflop computing rate and have a memory capacity of 1 billion 64-bit words. Remote access to the system through UNIX-based microcomputers will be available through land lines and satellite links. New supercomputers will be tested on the system without disturbing ongoing work. The core machine will be a Cray-2 with a 2 Gflop rate.

Bailey, F. R.↗
NASA NTRS1990

The AMPTE program's contribution to studies of the solar wind-magnetosphere-ionosphere interaction

The Active Magnetospheric Particle Tracer Explorers (AMPTE) program provided important information on the behavior of clouds of plasma artificially injected into the solar wind and the earth's magnetosphere. Now that the releases are over, data from the satellites are being analyzed to investigate the processes by which the ambient solar wind mass, momentum, and energy are transferred to the magnetosphere. Work in progress at APL indicates that the solar wind is much more inhomogeneous than previously believed, that the solar wind constantly buffets the magnetosphere, and that ground observers may remotely sense these interactions as geomagnetic pulsations.

Sibeck, David G.↗
NASA NTRS1997

JOVE

The focus of our JOVE research has been to develop a field instrument that provides high quality data for atmospheric corrections and in-flight calibration of airborne and satellite remote sensing imaging systems. The instrument package is known as the Portable Ground-based Atmospheric Monitoring System or PGAMS. PGAMS collects a comprehensive set of spectroscopic/radiometric observations that describe the optical properties of the atmosphere and reflectance of a target area on the earth's surface at the time of the aircraft or satellite overpass. To date, the PGAMS instrument system and control software has been completed and used for data collection in several NASA field experiments across the continental US and Puerto Rico. Where do you see your JOVE research going after the initial JOVE Funding Expires? Our JOVE initiated research will continue to be very active in supporting validation and calibration activities in remote sensing involving NASA, DOE, DOD, NSF, and possibly commercial supported programs. Future effort will focus on projects related to NASA's Mission to Planet Earth. This will include field work using PGAMS and data analysis that evaluates sensor calibration and atmospheric effects in images recorded by ASTER, MODIS, and MISR instruments aboard the AM-1 platform.

Schiller, Stephen↗
NASA NTRS1996

A Study of Uranus' Bow Shock Motions Using Langmuir Waves

During the Voyager 2 flyby of Uranus, strong electron plasma oscillations (Langmuir waves) were detected by the plasma wave instrument in the 1.78-kHz channel on January 23-24, 1986, prior to the inbound bow shock crossing. Langmuir waves are excited by energetic electrons streaming away from the bow shock. The goal of this work is to estimate the location and motion of Uranus' bow shock using Langmuir wave data, together with the spacecraft positions and the measured interplanetary magnetic field. The following three remote sensing analyses were performed: the basic remote sensing method, the lag time method, and the trace-back method. Because the interplanetary magnetic field was highly variable, the first analysis encountered difficulties in obtaining a realistic estimation of Uranus' bow shock motion. In the lag time method developed here, time lags due to the solar wind's finite convection speed are taken into account when calculating the shock's standoff distance. In the new trace-back method, limits on the standoff distance are obtained as a function of time by reconstructing electron paths. Most of the results produced by the latter two analyses are consistent with predictions based on the standard theoretical model and the measured solar wind plasma parameters. Differences between our calculations and the theoretical model are discussed.

Xue, S.↗
NASA NTRS2000

Ground Based, Millimeter Wave Measurement of Ozone in the Middle Atmosphere

There is a need for highly reliable measurements of stratospheric ozone. Policy makers worldwide concerned with public health rely oil a clear consensus from the scientific community as a basis for ozone-related environmental policy that has a significant impact oil national economies. Tile latest Such consensus was presented in WMO, and used in a 1999 meeting of the parties considering amendments to the Montreal Protocol oil Substances that Deplete the Ozone Layer. Tile scientific community, in turn, needs highly precise and accurate measurements of ozone levels, and small time derivatives of these levels, both in continued - development of its understanding of the physical and chemical processes involved and as clear evidence that these processes are occurring as stated. Over most of the world, changes in ozone levels are small. For example, over the heavily populated northern midlatitudes, the linearized rate of ozone decline is between 0.2% per year and 0.7% per year, depending on altitude. These values are small enough to make measurement requirements technically challenging. Data quality may suffer from imperfections in individual instruments. In one instance, early results from a satellite-borne ozone sensor were later found to be invalid because of calibration drift. Even in the absence of drift, tile absolute calibration of a new sensor may differ slightly from that of its predecessor in service. Most ozone remote sensing instruments operate at ultraviolet or infrared wavelengths where scattering from dust and aerosols must be taken into account; results from these systems may be or are affected following a major volcanic eruption, such as tile one at Mt. Pinatubo in 1991. Given these difficulties, a consensus of measurements from several independent systems is required to insure a reliable understanding of stratospheric ozone levels. Because of the above-described need for highly precise and accurate ozone measurements using several independent techniques, there was interest in developing several techniques which were known but not highly developed in the 1980's into systems capable of being used in ail operational manner to make measurements with the level of quality needed to-detect small trends in ozone levels. A ground-based microwave instrument capable of remotely sensing stratospheric ozone had been designed by tile Principal Investigator of the present project. This instrument was built at tile Millitech Corporation in South Deerfield, Massachusetts before tile present work began. (Funding for design and construction of the instrument came from sources other than the present grant.) Tile instrument measured the spectrum of one of the many emission lines produced by purely rotational transitions of ozone, one at a frequency of 110.8 GHz. The altitude distribution of ozone can. in principle, be retrieved from the details of the pressure-broadened spectrum of the ozone transition. However, the level of contamination of the spectral measurement by instrumentally induced artifacts must be very low in order to retrieve a ozone profile of useful quality from it. The Millitech instrument demonstrated spectral purity at ail adequate level, and there were promising ideas for instrumental improvements and for further development of the technique. The initial objectives of the present project, then, were to develop techniques for calibrating the Millitech instrument, to minimize artifacts in tile spectra it produces, to optimally retrieve ozone profiles from tile spectra, to test tile quality of the microwave profiles by comparing them with profiles obtained using several other, independent techniques over both short and periods of time, and to perform research using the ozone data gathered with the instrument.

Parrish, Alan↗
NASA NTRS2005

Simulation Results of the Huygens Probe Entry and Descent Trajectory Reconstruction Algorithm

Cassini/Huygens is a joint NASA/ESA mission to explore the Saturnian system. The ESA Huygens probe is scheduled to be released from the Cassini spacecraft on December 25, 2004, enter the atmosphere of Titan in January, 2005, and descend to Titan s surface using a sequence of different parachutes. To correctly interpret and correlate results from the probe science experiments and to provide a reference set of data for "ground-truthing" Orbiter remote sensing measurements, it is essential that the probe entry and descent trajectory reconstruction be performed as early as possible in the postflight data analysis phase. The Huygens Descent Trajectory Working Group (DTWG), a subgroup of the Huygens Science Working Team (HSWT), is responsible for developing a methodology and performing the entry and descent trajectory reconstruction. This paper provides an outline of the trajectory reconstruction methodology, preliminary probe trajectory retrieval test results using a simulated synthetic Huygens dataset developed by the Huygens Project Scientist Team at ESA/ESTEC, and a discussion of strategies for recovery from possible instrument failure.

Kazeminejad, B.↗
NASA NTRS2012

Low SWaP Semiconductor Laser Transmitter Modules For ASCENDS Mission Applications

The National Research Council's (NRC) Decadal Survey (DS) of Earth Science and Applications from Space has identified the Active Sensing of CO2 Emissions over Nights, Days, and Seasons (ASCENDS) as an important atmospheric science mission. NASA Langley Research Center, working with its partners, is developing fiber laser architecture based intensity modulated CW laser absorption spectrometer for measuring XCO2 in the 1571 nm spectral band. In support of this measurement, remote sensing of O2 in the 1260 nm spectral band for surface pressure measurements is also being developed. In this paper, we will present recent progress made in the development of advanced transmitter modules for CO2 and O2 sensing. Advanced DFB seed laser modules incorporating low-noise variable laser bias current supply and low-noise variable temperature control circuit have been developed. The 1571 nm modules operate at >80 mW and could be tuned continuously over the wavelength range of 1569-1574nm at a rate of 2 pm/mV. Fine tuning was demonstrated by adjusting the laser drive at a rate of 0.7 pm/mV. Heterodyne linewidth measurements have been performed showing linewidth ~200 kHz and frequency jitter ~75 MHz. In the case of 1260 nm DFB laser modules, we have shown continuous tuning over a range of 1261.4 - 1262.6 nm by changing chip operating temperature and 1261.0 - 1262.0 nm by changing the laser diode drive level. In addition, we have created a new laser package configuration which has been shown to improve the TEC coefficient of performance by a factor of 5 and improved the overall efficiency of the laser module by a factor of 2.

Prasad, Narasimha S.↗
NASA NTRS2012

Short Trips and a Traverse

Dr. Cameron joined the Arctic Institute of North America in 1956 to participate in IGY-related activities in Antarctica. He served as Chief Glaciologist at Wilkes Station, on the coast of East Antarctica. This was a joint Navy-civilian operation consisting of 17 Navy personnel and 10 scientists. Specifically, his glaciological team consisted of two colleagues with whom he had worked before - Olav Loken in Norway in the summer of 1953, and John Molholm in Greenland in the summer of 1954. This team spent much of its time at a remote station established 80 kilometers (50 miles) inland, where they conducted both meteorological and glaciological studies. One of the glaciological studies entailed digging a 35-meter (approx.115-foot) vertical pit to study snow densification and stratigraphy. The assignment for the Navy Seabees was to first establish a joint US-NZ base at Cape Hallett and then go along the coast of East Antarctica and set up Wilkes Station.

Cameron, Richard↗
NASA NTRS2022

Automating Surface Attitude Positioning and Pointing Operations for Mars 2020

The Surface Attitude Positioning and Pointing (SAPP) subsystem of the Mars Perseverance rover keeps track of the rover’s position and attitude on the surface of Mars. The SAPP Downlink Engineering Operations team members receive data from the rover on a daily basis. They must interpret the data to make sure the rover is staying safe and to support uplink planning. The SAPP team keeps track of the error growth in the rover’s attitude estimate due to noise in the Rover Inertial Measurement Unit’s (RIMU) gyroscopes used to propagate that attitude estimate whenever the rover is moving. Whenever this error grows to a particular threshold, SAPP is responsible for updating the onboard attitude knowledge using the RIMU’s accelerometers to estimate rover roll and pitch and sun imaging to estimate rover yaw, thereby reducing this attitude estimation error. Accurate attitude estimation is required so that the rover can successfully point its High Gain Antenna (HGA) to receive information from Earth and as a backup to the Mars orbiters used for sending data from the rover to Earth, point instruments on its Remote Sensing Mast (RSM), and support safe movement and placement of instruments by the rover’s ARM relative to the Martian surface. The Mars 2020 Engineering Operations team has been working to increase the operational efficiency of the mission and eventually move to a five-hour timeline for daily operations. In pursuit of this goal, the SAPP Engineering Operations team has automated their downlink process by developing a centralized Jupyter notebook to analyze the data received daily from the rover. The SAPP downlink Jupyter notebook automatically collects the data relevant to the SAPP subsystem and visualizes this information in plots and tables that can be easily read by downlink operators to aid them in assessing the status of the subsystem. Various Application Programming Interfaces (APIs) have been incorporated into the downlink daily notebook to automate the collection and posting of data, such as gathering and posting data products to the cloud. The SAPP team has also developed a SAPP downlink software library that includes functions to aid the notebook in processing data. In addition to assessing the SAPP subsystem on a daily basis, operators need to assess the long-term trending behavior of the subsystem over time. An automated trending process has been developed to collect information from the daily notebooks in order to plot and analyze that data in a centralized place. These daily and trending processes have expedited the SAPP downlink assessment and laid the groundwork to completely automate the SAPP downlink process so that SAPP operators are unnecessary unless something unexpected occurs. This paper will provide an overview of the functions that the SAPP subsystem carries out on a daily basis, and will then dive into the automations that have been developed for daily and trending downlink assessment. An assessment of the downlink efficiency will be provided, along with a summary of lessons learned and work to go. Finally, the authors will discuss how these types of automated spacecraft health assessments could be more broadly used within mission operations.

Zarifian, Anais↗