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All sourcesNASA NTRSDOE OSTI
NASA NTRS2015

Attitude Design for the LADEE Mission

The Lunar Atmosphere and Dust Environment Explorer (LADEE) satellite successfully completed its 148-day science investigation in a low-altitude, near-equatorial lunar orbit on April 18, 2014. The LADEE spacecraft was built, managed and operated by NASA's Ames Research Center (ARC). The Mission Operations Center (MOC) was located at Ames and was responsible for activity planning, command sequencing, trajectory and attitude design, orbit determination, and spacecraft operations. The Science Operations Center (SOC) was located at Goddard Space Flight Center and was responsible for science planning, data archiving and distribution. This paper details attitude design and operations support for the LADEE mission. LADEE's attitude design was shaped by a wide range of instrument pointing requirements that necessitated regular excursions from the baseline one revolution per orbit "Ram" attitude. Such attitude excursions were constrained by a number of flight rules levied to protect instruments from the Sun, avoid geometries that would result in simultaneous occlusion of LADEE's two star tracker heads, and maintain the spacecraft within its thermal and power operating limits. To satisfy LADEE's many attitude requirements and constraints, a set of rules and conventions was adopted to manage the complexity of this design challenge and facilitate the automation of ground software that generated pointing commands spanning multiple days of operations at a time. The resulting LADEE Flight Dynamics System (FDS) that was developed used Visual Basic scripts that generated instructions to AGI's Satellite Tool Kit (STK) in order to derive quaternion commands at regular intervals that satisfied LADEE's pointing requirements. These scripts relied heavily on the powerful "align and constrain" capability of STK's attitude module to construct LADEE's attitude profiles and the slews to get there. A description of the scripts and the attitude modeling they embodied is provided. One particular challenge analysts faced was in the design of LADEE maneuver attitudes. A flight rule requiring pre-maneuver verification of in-flight maneuver conditions by ground operators prior to burn execution resulted in the need to accommodate long periods in the maneuver attitude. This in turn complicated efforts to satisfy star tracker interference and communication constraints in lunar orbit. In response to this challenge, a graphical method was developed and used to survey candidate rotation angles about the thrust vector. This survey method is described and an example of its use on a particular LADEE maneuver is discussed. Finally, the software and methodology used to satisfy LADEE's attitude requirements are also discussed in the context of LADEE's overall activity planning effort. In particular, the way in which strategic schedules of instrument and engineering activities were translated into actual attitude profiles at the tactical level, then converted into precise quaternion commands to achieve those pointing goals is explained. In order to reduce the risk of time-consuming re-planning efforts, this process included the generation of long-term projections of constraint violation predictions for individual attitude profiles that could be used to establish keep-out time-frames for particular attitude profiles. The challenges experienced and overall efficacy of both the overall LADEE ground system and the attitude components of the Flight Dynamics System in meeting LADEE's varied pointing requirements are discussed.

LADEE↗
NASA NTRS1984

Space Station power system

A Space Station Task Force was established by the NASA Administrator in May 1982 to provide focus and direction for Space Station planning activities. The Task Force also provides Congress and the Administration with sufficient information to allow them to make an informed decision on whether the United States should proceed with a Space Station as the next major national initiative in space. This paper will present the status of planning activities to date, with major emphasis on the power system. Technology options, power requirements, and schedule will be discussed.

Forestieri, A. F.↗
NASA NTRS1987

Supersonic STOVL propulsion technology program: An overview

Planning activities are continuing between NASA, DOD, and two foreign governments to develop the technology and to demonstrate the design capability for advanced, supersonic, short-takeoff and vertical-landing (STOVL) aircraft by the mid-1990s. As a result, a Memorandum of Understanding (MOU) was established by the United Kingdom to jointly pursue the required technology; and an MOU with Canada is expected to be signed shortly. The NASA Lewis Research Center will play a lead role in the development of the required propulsion technologies which were identified as being critical to achieve viable STOVL aircraft. These planning activities have already resulted in initial research programs focused on technologies common to two or more of the proposed propulsion system concepts. An overview of the Lewis Research Center's role in the overall program plan and recent results in the development of the required propulsion technologies is presented.

Blaha, Bernard J.↗
NASA NTRS2009

NASA Lunar Mining and Construction Activities and Plans

The Space Exploration Policy enacted by the US Congress in 2005 calls for the US National Aeronautics and Space Administration (NASA) to implement a sustained and affordable human and robotic program to explore the solar system and beyond; Extend human presence across the solar system, starting with a human return to the Moon by the year 2020, in preparation for human exploration of Mars and other destinations; Develop the innovative technologies, knowledge, and infrastructures both to explore and to support decisions about the destinations for human exploration; and Promote international and commercial participation in exploration to further U.S. scientific, security, and economic interests. In 2006, NASA released the Lunar Architecture Study, which proposed establishing a lunar Outpost on the Moon with international participation to extend human presence beyond Earth's orbit, pursue scientific activities, use the Moon to prepare for future human missions to Mars, and expand Earth s economic sphere. The establishment of sustained human presence on the Moon for science and exploration combines the design, integration, and operation challenges experienced from both the short Apollo lunar missions and the build-up and sustained crew operations of the International Space Station (ISS). Apollo experience reminds developers and mission planners that hardware must operate under extremely harsh environmental and abrasive conditions and every kilogram of mass and payload must be critical to achieve the mission s objectives due to the difficulty and cost of reaching the lunar surface. Experience from the ISS reminds developers and mission planners that integration of all hardware must be designed and planned from the start of the program, operations and evolution of capabilities on a continuous basis are important, and long-term life-cycle costs and logistical needs are equally or more important than minimizing early development and test costs. Overarching all of this is the need to implement efforts that are sustainable and affordable. One area NASA is developing that can significantly change how systems required for sustained human presence are designed and integrated, as well as potentially break our reliance on Earth supplied logistics, is In-Situ Resource Utilization (ISRU). ISRU, also known living off the land, involves the extraction and processing of local resources into useful products. In particular, the ability to make propellants, life support consumables, fuel cell reagents, and radiation shielding can significantly reduce the cost, mass, and risk of sustained human activities beyond Earth. Also, the ability to modify the lunar landscape for safer landing, transfer of payloads from the lander an outpost, dust generation mitigation, and infrastructure placement and buildup are also extremely important for long-term lunar operations. While extra-terrestrial excavation, material handling and processing, and site preparation and construction may be new to NASA and other space agencies, there is extensive terrestrial hardware and commercial experience that can be leveraged. This paper will provide an overview of current NASA activities in lunar ISRU mining and construction and how terrestrial experience in these areas are important to achieving the goal of affordable and sustainable human exploration.

Sanders, Gerald B.↗
NASA NTRS1964

Inflight crew activities.

In flight crew activities covering detailed flight plan, activities and procedures, checklists and summary

ASTRONAUT PERFORMANCE↗
NASA NTRS1993

Mission and science activity scheduling language

To support the distributed and complex operational scheduling required for future National Aeronautics and Space Administration (NASA) missions, a formal, textual language, the Scheduling Applications Interface Language (SAIL), has been developed. Increased geographic dispersion of investigators is leading to distributed mission and science activity planning, scheduling, and operations. SAIL is an innovation which supports the effective and efficient communication of scheduling information among physically dispersed applications in distributed scheduling environments. SAIL offers a clear, concise, unambiguous expression of scheduling information in a readable, hardware independent format. The language concept, syntax, and semantics incorporate language features found useful during five years of research and prototyping with scheduling languages in physically distributed environments. SAIL allows concise specification of mission and science activity plans in a format which promotes repetition and reuse.

Hull, Larry G.↗
NASA NTRS2012

3D Visualization for Phoenix Mars Lander Science Operations

Planetary surface exploration missions present considerable operational challenges in the form of substantial communication delays, limited communication windows, and limited communication bandwidth. A 3D visualization software was developed and delivered to the 2008 Phoenix Mars Lander (PML) mission. The components of the system include an interactive 3D visualization environment called Mercator, terrain reconstruction software called the Ames Stereo Pipeline, and a server providing distributed access to terrain models. The software was successfully utilized during the mission for science analysis, site understanding, and science operations activity planning. A terrain server was implemented that provided distribution of terrain models from a central repository to clients running the Mercator software. The Ames Stereo Pipeline generates accurate, high-resolution, texture-mapped, 3D terrain models from stereo image pairs. These terrain models can then be visualized within the Mercator environment. The central cross-cutting goal for these tools is to provide an easy-to-use, high-quality, full-featured visualization environment that enhances the mission science team s ability to develop low-risk productive science activity plans. In addition, for the Mercator and Viz visualization environments, extensibility and adaptability to different missions and application areas are key design goals.

Edwards, Laurence↗
NASA NTRS2005

Crew-Centered Operations: What HAL 9000 Should Have Been

To date, manned space flight has maintained the locus of control for the mission on the ground. Mission control performs tasks such as activity planning, system health management, resource allocation, and astronaut health monitoring. Future exploration missions require the locus of control to shift to on-board due light speed constraints and potential loss of communication. The lunar campaign must begin to utilize a shared control approach to validate and understand the limitations of the technology allowing astronauts to oversee and direct aspects of operation that require timely decision making. Crew-centered Operations require a system-level approach that integrates multiple technologies together to allow a crew-prime concept of operations. This paper will provide an overview of the driving mission requirements, highlighting the limitations of existing approaches to mission operations and identifying the critical technologies necessary to enable a crew-centered mode of operations. The paper will focus on the requirements, trade spaces, and concepts for fulfillment of this capability. The paper will provide a broad overview of relevant technologies including: Activity Planning and Scheduling; System Monitoring; Repair and Recovery; Crew Work Practices.

Korsmeyer, David J.↗
NASA NTRS2010

Soil Moisture Active Passive (SMAP) Calibration and Validation Plan and Current Activities

The primary objective of the SMAP calibration and validation (Cal/Val) program is demonstrating that the science requirements (product accuracy and bias) have been met over the mission life. This begins during pre-launch with activities that contribute to high quality products and establishing post-launch validation infrastructure and continues through the mission life. However, the major focus is on a relatively short Cal/Val period following launch. The general approach and elements of the SMAP Cal/Val plan will be described and along with details on several ongoing or recent field experiments designed to address both near- and long-term Cal/Val.

Jackson, T. J.↗
NASA NTRS1975

Transport of trace contaminants through porous media

Research accomplishments in the following areas are discussed: (1) the calibration of the gas chromatograph for acetaldehyde and ethanol; (2) the development of data reduction and analysis methods; (3) the generation and analysis of experimental data for the transport of 100 ppm acetaldehyde through a cylindrical bed packed with activated carbon granules; (4) the generation and analysis of experimental data for the transport of 100 ppm ethanol through a cylindrical bed packed with activated carbon granules; and (5) a comparison of the volume adsorption capacity of activated carbon for 100 ppm concentrations of acetaldehyde, ethanol, and acetone. Activities in progress and planned activities are reviewed.

Madey, R.↗
NASA NTRS1981

NASA activities and plans

An overview is provided of the NASA tracking, data acquisition, communications, and mission control systems and capabilities. These systems include the NASA Spaceflight Tracking and Data Network (STDN) which supports earth-orbital spacecraft, the Deep Space Network (DSN) which supports the planetary exploration and deep space missions, and the Tracking and Data Relay Satellite System (TDRSS) currently under development and scheduled to come into service in 1983. TDRSS will then displace STDN for support of low earth orbital spacecraft. A description is presented of the current status of the considered systems, and plans are discussed for future developments and new capabilities.

Smylie, R. E.↗
NASA NTRS1985

FSA future directions: Reliability and engineering sciences FY85-FY86 activities and plans

Objectives were listed for four areas: engineering science, reliability physics, module development, and module performance and failure analysis. The engineering science efforts are to develop module design requirements for large-scale photovoltaic (PV) applications and to develop generic module and array design and construction technology to meet the needed performance, safety, reliability, and system interfaces. The reliability physics effort is to develop the technology for 30-year life modules. The module development efforts are to transfer new technology to PV manufacturers and their products, and to evaluate these advanced modules. The module performance and failure analysis efforts are to determine PV module performance, to identify needed development, and to assess suitability for large-scale use.

Ross, R. G., Jr.↗
NASA NTRS1999

Mars 2001 Lander Mission: Measurement Synergy Through Coordinated Operations Planning And Implementation

The 2001 Mars Surveyor Program Mission includes an orbiter with a gamma ray spectrometer and a multispectral thermal imager, and a lander with an extensive set of instrumentation, a robotic arm, and the Marie Curie Rover. The Mars 2001 Science Operations Working Group (SOWG) is a subgroup of the Project Science Group that has been formed to provide coordinated planning and implementation of scientific observations, particularly for the landed portion of the mission. The SOWG will be responsible for delivery of a science plan and, during operations, generation and delivery of conflict-free sequences. This group will also develop an archive plan that is compliant with Planetary Data System (PDS) standards, and will oversee generation, validation, and delivery of integrated archives to the PDS. In this report we cover one element of the SOWG planning activities, the development of a plan that maximizes the scientific return from lander-based observations by treating the instrument packages as an integrated payload. Scientific objectives for the lander mission have been defined. They include observations focused on determining the bedrock geology of the site through analyses of rocks and also local materials found in the soils, and the surficial geology of the site, including windblown deposits and the nature and history of formation of indurated sediments such as duricrust. Of particular interest is the identification and quantification of processes related to early warm, wet conditions and the presence of hydrologic or hydrothermal cycles. Determining the nature and origin of duricrust and associated salts is -very important in this regard. Specifically, did these deposits form in the vadose zone as pore water evaporated from soils or did they form by other processes, such as deposition of volcanic aerosols? Basic information needed to address these questions includes the morphology, topography, and geologic context of landforms and materials exposed at the site, together with quantitative information on material mineralogy, chemistry, and physical properties (rock textures; soil grain size and shape distributions; degree and nature of soil induration; soil magnetic properties). The calibration targets provide radiometric and mineralogical control surfaces. The magnets allow observations of magnetic phases. Patch plates are imaged to determine adhesive and abrasive properties of soils. Coordinated mission planning is crucial for optimizing the measurement synergy among the packages included on the lander. This planning has already begun through generation of multi-sol detailed operations activities. One focus has been to develop a scenario to use the arm to dig a soil trench to a depth of tens of centimeters. The activity will be monitored through use of Pancam and RAC to ensure nominal operations and to acquire data to determine subsurface physical properties (e.g., angle of repose of trench walls). Pancam and Mini-TES observations would also provide constraints on mineralogy and texture for the walls and bottom of the trench during excavation. If desired, soils excavated at depth could be deposited on the surface and Mossbauer and APXS measurements could be acquired for these materials. Soil samples from various depths would be delivered to MECA for characterization of aqueous geochemistry and physical properties of soil grains, particularly size, shape, and hardness. These physical properties would be determined by optical and atomic force microscopy. When completed, detailed information of soil properties as a function of depth would be obtained. These various data sets would constrain our understanding of whether or not there are systematic variations in soil characteristics as a function of depth. These variations might be related, for example, to evaporative moisture losses and formation of salt deposits, thereby indicating water transport processes occurred fairly recently. Many other value-added measurement scenarios are being developed. For example, characterizing the nature and dynamics of dust deposition will be done using MIP/DART to provide deposition rates, Pancam and RAC imaging of lander and rover surfaces to extrapolate these measurements to other areas, and a variety of measurements to determine if the bulk loose soil has the same characteristics as dust that accumulates during the mission. Bedrock geology of the site is primarily an APEX-focus setting, mineralogy, and texture, and APXS data to be we interest will be to determine the extent to which rock hydrothermal processes, given that APEX is the precursor 4 and 2005 rover missions. Additional information is contained in the original.

Arvidson, R.↗
NASA NTRS1989

MAX 1991. The active sun: A plan for pursuing the study of the active sun at the time of the next maximum in solar activity, January 1985

The results of the discusions of a working group for the definition of a program for the forthcoming crest of solar activity, 1990 to 1993 are presented. The MAX '91 program described are intended to achieve important scientific goals within the context of the natural solar variability. The heart of the MAX '91 program is a series of campaigns oriented towards specific scientific problems, and taking place in the solar maximum period 1990 to 1993. These campaigns will take advantage of the load-carrying capability of the Space Shuttle to fly instruments with observational capabilities very different from those of the Solar Maximum Mission. Various combinations of instruments appropriate to the specific scientific problem of a given campaign would be flown on a Shuttle sortie mission.

Acton, L.↗