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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.

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NASA NTRS1990

Platform evolution studies

The polar orbiting platform (POP), being developed by the Work Package 3 (WP3) Project at the Goddard Space Flight Center, will play a key role in the NASA Leadership Initiative, Mission to Planet Earth (MPE). It becomes, with the addition of payloads, an Earth observation satellite observatory. Mission to Planet Earth also has geostationary platforms (GEOP) as part of its global observational system. A study was begun in March 1988 to assess the applicability of the POP orbital replacement units (ORUs) for a geostationary Earth observing mission. Two test cases, representative of MPE payloads, were studied. Case A was used to emphasize the GEOP configuration and design; it used a Titan/Centaur to achieve orbit. Case B, considered to be much further in the future, included some assembly at the Space Station Freedom manned base and use of an orbital transfer vehicle to achieve orbit; requirements on the manned base to support such a mission were emphasized. The study found the POP systems more than adequate to meet GEOP requirements. Two types of changes were required for the POP ORUs: (1) modification to use only one surface for heat rejection; for the battery ORU, this meant 'opening up' the ORU to retain the radiator area with a corresponding decrease in depth; and (2) deletion of equipment not needed. The Case A configuration was shown to be within the planned capability of the Titan IV/Centaur. Assembly requirements were included for the Case B configuration, which is driven by the large microwave antennas of two of the payloads. The final review was April 19, 1989.

Walton, Barbara A.↗

NASA NTRS2017

International Space Station Lithium-Ion Battery Start-Up and Cycling

The International Space Station (ISS) primary Electric Power System (EPS) was originally designed to use Nickel-Hydrogen (Ni-H2) batteries to store electrical energy. The electricity for the ISS is generated by its solar arrays, which charge batteries during insolation for subsequent discharge during eclipse. The Ni-H2 batteries were designed to operate at a 35 depth of discharge (DOD) maximum during normal operation in a Low Earth Orbit. In 2010, the ISS Program began the development of Lithium-Ion (Li-Ion) batteries to replace Ni-H2 batteries approaching the end of their useful life and concurrently funded a Li-Ion ORU (Orbital Replacement Unit) and cell life testing project. The first set of 6 Li-ion battery replacements was launched in December 2016 and deployed in January 2017. This paper will discuss the Li-ion battery on-orbit cycling and the status of the Li-Ion cell and ORU life cycle testing.

International Space Station↗

NASA NTRS2004

International Space Station Nickel-Hydrogen Batteries Approached 3-Year On-Orbit Mark

The International Space Station's (ISS) electric power system (EPS) employs nickel-hydrogen (Ni-H2) batteries as part of its power system to store electrical energy. The batteries are charged during insolation and discharged, providing station power, during eclipse. The batteries are designed to operate at a maximum 35-percent depth of discharge during normal operation. Thirty-eight individual pressure vessel Ni-H2 battery cells are series-connected and packaged in an orbital replacement unit (ORU), and two ORUs are series-connected, using a total of 76 cells, to form one battery. When the ISS is in its assembly-complete form, the electrical power system will have a total of 24 batteries (48 ORUs) on-orbit. The ISS is the first application for low-Earth-orbit cycling of this quantity of series-connected cells.

Dalton, Penni J.↗

NASA NTRS1996

Comparison of System Identification Techniques for the Hydraulic Manipulator Test Bed (HMTB)

In this thesis linear, dynamic, multivariable state-space models for three joints of the ground-based Hydraulic Manipulator Test Bed (HMTB) are identified. HMTB, housed at the NASA Langley Research Center, is a ground-based version of the Dexterous Orbital Servicing System (DOSS), a representative space station manipulator. The dynamic models of the HMTB manipulator will first be estimated by applying nonparametric identification methods to determine each joint's response characteristics using various input excitations. These excitations include sum of sinusoids, pseudorandom binary sequences (PRBS), bipolar ramping pulses, and chirp input signals. Next, two different parametric system identification techniques will be applied to identify the best dynamical description of the joints. The manipulator is localized about a representative space station orbital replacement unit (ORU) task allowing the use of linear system identification methods. Comparisons, observations, and results of both parametric system identification techniques are discussed. The thesis concludes by proposing a model reference control system to aid in astronaut ground tests. This approach would allow the identified models to mimic on-orbit dynamic characteristics of the actual flight manipulator thus providing astronauts with realistic on-orbit responses to perform space station tasks in a ground-based environment.

Morris, A. Terry↗

NASA NTRS2021

Spectrum – An Instrument for Multispectral Biological Fluorescence Imaging on the International Space Station

Spectrum is a compact instrument for fluorescent imaging of biological specimens in microgravity and capable of operating within the constraints of an EXPRESS Rack on the International Space Station (ISS). The Spectrum Flight Unit (SFU) was launched to ISSin November 2019 and is available for science investigations as a general instrument. A duplicate Engineering Development Unit (EDU) is available at NASA Kennedy Space Center (KSC). Science Verification Testing (SVT) performed at KSCdemonstrated all required functions including five (5) fluorescence excitation wavelengths, growth lighting, environmental controls and monitoring, and high-resolution imaging using a 71 Megapixel camera with flat field lens. The design features key Orbital Replaceable Unit (ORU) components, which may be adapted or changed by future investigators for tailored science experiments.

Bradley Burns↗

NASA NTRS2011

Investigation of International Space Station Major Constituent Analyzer Anomalous ORU 02 Performance

The Major Constituent Analyzer (MCA) is a mass spectrometer-based instrument designed to provide critical monitoring of six major atmospheric constituents; nitrogen, oxygen, hydrogen, carbon dioxide, methane, and water vapor on-board the International Space Station. It is an integral part of the Environmental Control and Life Support System (ECLSS). The MCA system is comprised of seven orbit-replaceable units (ORUs) that provide flexibility in maintaining the MCA. Of these, ORU 02, the analyzer assembly requires replacement every 1 to 2 years due to the consumption of limited life components including the ion pump and ion source filaments. Typically, ORU 02s that reach end of life are swapped out of the MCA on orbit and replaced with the on-orbit spare. The replaced ORU 02 is then returned to the OEM for refurbishment and is then return to service. Recently, 2 refurbished ORU 02s, serial numbers F0001 and F0003, failed on orbit shortly after being installed into the MCA. Both ORU 02s have been returned to ground for TT&E, and a failure investigation is underway. The failure signatures have been reproduced on the ground and an initial investigation has determined that both ORU 02 failures involve either the ion source or the ion source control electronics. This paper discusses the results of the failure investigation, the steps required to refurbish the ORU 02s, and the risk mitigation steps that are being incorporated into the refurbishment process to preclude the reoccurrence of these failures in the future

Gardner, Ben D.↗

NASA NTRS2012

Investigation of International Space Station Major Constituent Analyzer Anomalous ORU 02 Performance

The Major Constituent Analyzer (MCA) is a mass spectrometer-based instrument designed to provide critical monitoring of six major atmospheric constituents; nitrogen, oxygen, hydrogen, carbon dioxide, methane, and water vapor on-board the International Space Station. It is an integral part of the Environmental Control and Life Support System (ECLSS). The MCA system is comprised of seven orbit-replaceable units (ORUs) that provide flexibility in maintaining the MCA. Of these, ORU 02, the analyzer assembly requires replacement every 1 to 2 years due to the consumption of limited life components including the ion pump and ion source filaments. Typically, ORU 02s that reach end of life are swapped out of the MCA on orbit and replaced with the on-orbit spare. The replaced ORU 02 is then cycled through the OEM for refurbishment and returned to service. Recently, two refurbished ORU 02s, serial numbers F0001 and F0003, failed on orbit shortly after being installed into the MCA. Both ORU 02s were returned to ground for TT&E and a failure investigation. The failure signatures were reproduced on the ground and the investigation determined that both ORU 02 failures involve either the ion source or the ion source control electronics. This paper discusses the results of the failure investigation, the steps required to refurbish the ORU 02s, and the corrective actions that are being incorporated into the build and refurbishment process to preclude the reoccurrence of these failures in the future.

Gardner, Ben D.↗

NASA NTRS1986

Servicing of user payload equipment in the Space Station pressurized environment

NASA Space Station servicing support facilities will include both pressurized and unpressurized work areas. While the latter will allow astronauts operating in EVAs or aided by robots to accomplish Orbital Replacement Unit (ORU) and instrument changes, tests, assembly, refueling, and repairs, the former will furnish astronauts engaged in work requiring intravehicular activities (IVAs) the ability to enter through an airlock into a module in which they can more carefully service ORUs. Baseline IVA accommodations encompass (1) a staging/assembly area for ORUs brought in from satellites, orbital platforms or attached payloads, (2) a work station for monitoring and control of the external Servicing Bay facility, and (3) a large, laminar flow workbench which would provide highly controlled conditions, as well as (4) a 'glovebox' for delicate servicing and (5) an assortment of hand tools and test equipment.

Levy, Joel↗

NASA NTRS1999

ISS Operations for the Special Purpose Dexterous Manipulator (SPDM) Experiences from the Robotic Systems Evaluation Laboratory (RSEL)

The International Space Station (ISS) will present a new era of telerobotic operations on-orbit. Operating the Special Purpose Dexterous Manipulator (SPDM) in its tasks of maintaining the multitude of Space Station Orbital Replaceable Units (ORUs) creates numerous operational considerations not seen in the existing Shuttle Remote Manipulator System (SRMS) or the future Space Station Remote Manipulator System (SSRMS). The differences between the large arms and the dexterous arm greatly affect the interconnection of man, robot, and task. This paper presents some of the issues arising from this new breed of on-orbit robotics as garnered from over three years of ORU testing experience within the Robotic Systems Evaluation Laboratory (RSEL) at NASA Johnson Space Center. The effects of new robotic features on operations, the issues surrounding targets and visual cues, the differences in operating with Force Moment Accommodation (FMA), the effects of changes in task complexity and scale, the lack of supporting flight information, and the changes in procedures required by the dexterous task will be discussed.

Spinler, Anthony B.↗

NASA NTRS2007

Improving Robotic Operator Performance Using Augmented Reality

The Special Purpose Dexterous Manipulator (SPDM) is a two-armed robot that functions as an extension to the end effector of the Space Station Robotics Manipulator System (SSRMS), currently in use on the International Space Station (ISS). Crew training for the SPDM is accomplished using a robotic hardware simulator, which performs most of SPDM functions under normal static Earth gravitational forces. Both the simulator and SPDM are controlled from a standard robotic workstation using a laptop for the user interface and three monitors for camera views. Most operations anticipated for the SPDM involve the manipulation, insertion, and removal of any of several types of Orbital Replaceable Unit (ORU), modules which control various ISS functions. Alignment tolerances for insertion of the ORU into its receptacle are 0.25 inch and 0.5 degree from nominal values. The pre-insertion alignment task must be performed within these tolerances by using available video camera views of the intrinsic features of the ORU and receptacle, without special registration markings. Since optimum camera views may not be available, and dynamic orbital lighting conditions may limit periods of viewing, a successful ORU insertion operation may require an extended period of time. This study explored the feasibility of using augmented reality (AR) to assist SPDM operations. Geometric graphical symbols were overlaid on one of the workstation monitors to afford cues to assist the operator in attaining adequate pre-insertion ORU alignment. Twelve skilled subjects performed eight ORU insertion tasks using the simulator with and without the AR symbols in a repeated measures experimental design. Results indicated that using the AR symbols reduced pre-insertion alignment error for all subjects and reduced the time to complete pre-insertion alignment for most subjects.

Maida, James C.↗

NASA NTRS2018

International Space Station Lithium-Ion Battery Status

When originally launched, the International Space Station (ISS) primary Electric Power System (EPS) used Nickel-Hydrogen (Ni-H2) batteries to store electrical energy. The electricity for the space station is generated by its solar arrays, which charge batteries during insolation for subsequent discharge during eclipse. The Ni-H2 batteries were designed to operate for ten years at a 35 percent depth of discharge (DOD) maximum during normal operation in a Low Earth Orbit. For service beyond that period, upgraded Li-Ion Orbital Replacement Units (ORUs) were designed. These are the largest Li-Ion batteries ever utilized for a human rated spacecraft. With the oldest 12 Ni-H2 battery ORUs cycling since September 2006, the first set of six was replaced by Li-Ion batteries in December 2016; the second set of six is planned for replacement in September 2018. This paper will include an overview of the ISS Li-Ion battery system architecture, on-orbit status of the first 6 batteries, start up of the second 6 batteries, and the status of the Li-Ion cell and ORU life cycle testing.

International Space Station↗

NASA NTRS1982

Working in space

The capabilities of the NASA Neutral Buoyancy Simulator (NBS) water tank test facility are described, with reference to the proving of crew-operated mechanisms incorporated by the Space Telescope (ST). There are 24 Orbital Replaceable Units which are subject to handling in space by suited crewmen of the Space Shuttle, the largest of which is comparable to a telephone booth and weighs over 700 lb. The water volume of the simulator is sufficient to accept a full-size mockup of the Space Shuttle cargo bay, in which all ST operations will be conducted. Early ST simulations tested the mechanisms which astronauts would operate during contingency operations. More recently, the simulation tasks have reflected maintenance objectives of ST orbital life prolongation. With the recent addition of a fully functional Remote Manipulator System and the Manned Maneuvering Unit, the simulator constitutes the most complete training ground for extravehicular activities extant.

Sanders, F. G.↗

NASA NTRS2017

International Space Station Lithium-Ion Battery Start-Up

International Space Station Lithium-Ion Battery Start-Up.The International Space Station (ISS) primary Electric Power System (EPS) was originally designed to use Nickel-Hydrogen (Ni-H2) batteries to store electrical energy. The electricity for the space station is generated by its solar arrays, which charge batteries during insolation for subsequent discharge during eclipse. The Ni-H2 batteries are designed to operate at a 35 depth of discharge (DOD) maximum during normal operation in a Low Earth Orbit. As the oldest of the 48 Ni-H2 battery Orbital Replacement Units (ORUs) has been cycling since September 2006, these batteries are now approaching their end of useful life. In 2010, the ISS Program began the development of Lithium-Ion (Li-ion) batteries to replace the Ni-H2 batteries and concurrently funded a Li-Ion ORU and cell life testing project. The first set of 6 Li-ion battery replacements were launched in December 2016 and deployed in January 2017. This paper will discuss the Li-ion battery on-orbit start-up and the status of the Li-Ion cell and ORU life cycle testing.

Lithium-Ion↗

NASA NTRS1987

In-orbit and laboratory exchange of ORUs designed/not designed for servicing

The practicality of employing a combination of automated and extravehicular activity forms of servicing in-orbit was demonstrated with the STS 41-C Solar Maximum Repair Mission. This shows that modular Orbital Replacement Units (ORUs) designed for servicing can be readily accommodated. Successful replacement of an experiment ORU, not designed for replacement, was performed following extensive preparations. In a laboratory, spacecraft ORUs were replaced using a completely preplanned automated approach. This was later done using a completely unstructured teleoperations mode including the complicated exchange of the instrument ORU. As a result of this effort and work on powered tools, an approach for combining these techniques is underway to produce a flight support system servicing aid to increase the STS astronauts' effective in-orbit servicing capability by several fold.

Davis, R.↗

NASA NTRS2019

International Space Station Lithium-Ion Battery Status

When originally launched, the International Space Station (ISS) primary Electric Power System (EPS) used Nickel-Hydrogen (Ni-H2) batteries to store electrical energy. The electricity for the space station is generated by its solar arrays, which charge batteries during insolation for subsequent discharge during eclipse. The Ni-H2 batteries were designed to operate for ten years at a 35% depth of discharge (DOD) maximum during normal operation in a Low Earth Orbit. For service beyond that period, upgraded Li-Ion Orbital Replacement Units (ORUs) were designed. These are the largest Li-Ion batteries ever utilized for a human rated spacecraft. The first set of six Ni-H2 batteries was replaced by Li-Ion batteries in December 2016; the second set of six was launched in September 2018 and installed in March 2019. The third set of six were launched in September 2019. Three batteries were installed in September 2019, with the remaining three to be installed in January 2020. This paper will include a brief overview of the ISS Li-Ion battery system architecture, start up of the second and third set of 6 batteries and the on-orbit status of all 18 batteries, plus the status of the Li-Ion cell life testing.

Lithium-Ion↗

NASA NTRS2011

International Space Station Major Constituent Analyzer On-Orbit Performance

The Major Constituent Analyzer (MCA) is an integral part of the International Space Station (ISS) Environmental Control and Life Support System (ECLSS). The MCA is a mass spectrometer-based instrument designed to provide critical monitoring of six major atmospheric constituents; nitrogen, oxygen, hydrogen, carbon dioxide, methane, and water vapor. These gases are sampled continuously and automatically in all United States On-Orbit Segment (USOS) modules via the Sample Distribution System (SDS). The MCA is the primary tool for management of atmosphere constituents and is therefore critical for ensuring a habitable ISS environment during both nominal ISS operations and campout EVA preparation in the Airlock. The MCA has been in operation in the US Destiny Laboratory Module for over 10 years, and a second MCA has been delivered to the ISS for Node 3 operation. This paper discusses the performance of the MCA over the two past year, with particular attention to lessons learned regarding the operational life of critical components. Recent data have helped drive design upgrades for a new set of orbit-replaceable units (ORUs) currently in production. Several ORU upgrades are expected to increase expected lifetimes and reliability.

Gardner, Ben D.↗

NASA NTRS1997

Development of Methods to Evaluate Safer Flight Characteristics

The goal of the proposed research is to begin development of a simulation that models the flight characteristics of the Simplified Aid For EVA Rescue (SAFER) pack. Development of such a simulation was initiated to ultimately study the effect an Orbital Replacement Unit (ORU) has on SAFER dynamics. A major function of this program will be to calculate fuel consumption for many ORUs with different masses and locations. This will ultimately determine the maximum ORU mass an astronaut can carry and still perform a self-rescue without jettisoning the unit. A second primary goal is to eventually simulate relative motion (vibration) between the ORU and astronaut. After relative motion is accurately modeled it will be possible to evaluate the robustness of the control system and optimize performance as needed. The first stage in developing the simulation is the ability to model a standardized, total, self-rescue scenario, making it possible to accurately compare different program runs. In orbit an astronaut has only limited data and will not be able to follow the most fuel efficient trajectory; therefore, it is important to correctly model the procedures an astronaut would use in orbit so that good fuel consumption data can be obtained. Once this part of the program is well tested and verified, the vibration (relative motion) of the ORU with respect to the astronaut can be studied.

Basciano, Thomas E., Jr.↗

NASA NTRS2005

Enhanced Lighting Techniques and Augmented Reality to Improve Human Task Performance

One of the most versatile tools designed for use on the International Space Station (ISS) is the Special Purpose Dexterous Manipulator (SPDM) robot. Operators for this system are trained at NASA Johnson Space Center (JSC) using a robotic simulator, the Dexterous Manipulator Trainer (DMT), which performs most SPDM functions under normal static Earth gravitational forces. The SPDM is controlled from a standard Robotic Workstation. A key feature of the SPDM and DMT is the Force/Moment Accommodation (FMA) system, which limits the contact forces and moments acting on the robot components, on its payload, an Orbital Replaceable Unit (ORU), and on the receptacle for the ORU. The FMA system helps to automatically alleviate any binding of the ORU as it is inserted or withdrawn from a receptacle, but it is limited in its correction capability. A successful ORU insertion generally requires that the reference axes of the ORU and receptacle be aligned to within approximately 0.25 inch and 0.5 degree of nominal values. The only guides available for the operator to achieve these alignment tolerances are views from any available video cameras. No special registration markings are provided on the ORU or receptacle, so the operator must use their intrinsic features in the video display to perform the pre-insertion alignment task. Since optimum camera views may not be available, and dynamic orbital lighting conditions may limit viewing periods, long times are anticipated for performing some ORU insertion or extraction operations. This study explored the feasibility of using augmented reality (AR) to assist with SPDM operations. Geometric graphical symbols were overlaid on the end effector (EE) camera view to afford cues to assist the operator in attaining adequate pre-insertion ORU alignment.

Maida, James C.↗