Pub Date : 2020-03-01DOI: 10.1109/AERO47225.2020.9172268
Neil Mchenry, Leah Davis, Israel Gomez, Noemi Coute, Natalie Roehrs, Celest Villagran, G. Chamitoff, A. Diaz-Artiles
An Extra-Vehicular Activity (EVA) is one of the most challenging operations during spaceflight. The current technology utilized during a spacewalk by an astronaut crewmember includes real-time voice loops and physical cuff checklists with procedures for the EVA. Recent advancements in electronics allow for miniaturized optical displays that can fit within a helmet and provide an alternative method for a crewmember to access mission data. Additionally, cameras attached to helmets provide EV astronauts' several Point of Views (POVs) to Mission Control Center (MCC) and Intra-Vehicular (IV) astronauts. These technologies allow for greater awareness to protect astronauts in space. This paper outlines the design and development of a custom augmented reality (AR) visor display to assist with human spaceflight operations, particularly with EVAs. This system can render floating text checklists, real-time voice transcripts, and waypoint information within the astronaut's Field of View (FOV). These visual components aim to reduce the limitations of how tasks are communicated currently. In addition, voice commands allow the crewmember to control the location of the augmented display, or modify how the information is presented. The team used the Microsoft HoloLens 1 Head Mounted Display (HMD) to create an Augmented Reality Environment (ARE) that receives and displays information for the EVA personnel. The ARE displays the human vitals, spacesuit telemetry, and procedures of the astronaut. The MCC and other astronauts can collaborate with the EVA crewmember through the use of a 3D telepresence whiteboard, which enables 2-way visual communication. This capability allows interaction with the environment of the EV astronaut without actually having to be outside the spacecraft or even onboard. Specifically, mission personnel in a Virtual Reality (VR) Oculus Rift head mounted display could draw shapes in the EV members' view to guide them towards a particular objective. To test the system, volunteers were asked to proceed through a mission scenario and evaluate the user interface. This occurred both in a laboratory setting and in an analog mockup at the National Aeronautics and Space Administration (NASA) Johnson Space Center (JSC), using both the Microsoft Hololens and Oculus Rift in coordination with the NASA Spacesuit User Interface Technologies for Students (SUITS) Competition. The major goal of testing the User Interface (UI) was determining features contributing to a minimized cognitive workload and improving efficiency of task completion. AR technology has the potential of dramatically improving EVA performance for future manned missions. With the HoloLens, the team implemented an efficient and elegant design that can be individualized by the user. The system provides as much functionality as possible while remaining simple to promote user-friendliness.
{"title":"Design of an AR Visor Display System for Extravehicular Activity Operations","authors":"Neil Mchenry, Leah Davis, Israel Gomez, Noemi Coute, Natalie Roehrs, Celest Villagran, G. Chamitoff, A. Diaz-Artiles","doi":"10.1109/AERO47225.2020.9172268","DOIUrl":"https://doi.org/10.1109/AERO47225.2020.9172268","url":null,"abstract":"An Extra-Vehicular Activity (EVA) is one of the most challenging operations during spaceflight. The current technology utilized during a spacewalk by an astronaut crewmember includes real-time voice loops and physical cuff checklists with procedures for the EVA. Recent advancements in electronics allow for miniaturized optical displays that can fit within a helmet and provide an alternative method for a crewmember to access mission data. Additionally, cameras attached to helmets provide EV astronauts' several Point of Views (POVs) to Mission Control Center (MCC) and Intra-Vehicular (IV) astronauts. These technologies allow for greater awareness to protect astronauts in space. This paper outlines the design and development of a custom augmented reality (AR) visor display to assist with human spaceflight operations, particularly with EVAs. This system can render floating text checklists, real-time voice transcripts, and waypoint information within the astronaut's Field of View (FOV). These visual components aim to reduce the limitations of how tasks are communicated currently. In addition, voice commands allow the crewmember to control the location of the augmented display, or modify how the information is presented. The team used the Microsoft HoloLens 1 Head Mounted Display (HMD) to create an Augmented Reality Environment (ARE) that receives and displays information for the EVA personnel. The ARE displays the human vitals, spacesuit telemetry, and procedures of the astronaut. The MCC and other astronauts can collaborate with the EVA crewmember through the use of a 3D telepresence whiteboard, which enables 2-way visual communication. This capability allows interaction with the environment of the EV astronaut without actually having to be outside the spacecraft or even onboard. Specifically, mission personnel in a Virtual Reality (VR) Oculus Rift head mounted display could draw shapes in the EV members' view to guide them towards a particular objective. To test the system, volunteers were asked to proceed through a mission scenario and evaluate the user interface. This occurred both in a laboratory setting and in an analog mockup at the National Aeronautics and Space Administration (NASA) Johnson Space Center (JSC), using both the Microsoft Hololens and Oculus Rift in coordination with the NASA Spacesuit User Interface Technologies for Students (SUITS) Competition. The major goal of testing the User Interface (UI) was determining features contributing to a minimized cognitive workload and improving efficiency of task completion. AR technology has the potential of dramatically improving EVA performance for future manned missions. With the HoloLens, the team implemented an efficient and elegant design that can be individualized by the user. The system provides as much functionality as possible while remaining simple to promote user-friendliness.","PeriodicalId":114560,"journal":{"name":"2020 IEEE Aerospace Conference","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124233660","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-03-01DOI: 10.1109/AERO47225.2020.9172570
Salahudden, Praful Kumar, V. S. Dwivedi, D. Giri, A. Ghosh
In this paper, a quaternion based linear quadratic controller (LQR) is designed for nadir pointing satellites. The stability of the proposed controller is proved for specified control input. Runge-Kutta (RK4) numerical scheme and constrained nonlinear optimization technique are adapted to perform the simulation for computation of optimal values of a gain matrix, control weighted matrix, error weighted matrix and Riccati matrix for designing LQR controller. Simulations are carried out for three categories of spacecraft's- nano, medium and large, showing quick response and high tolerance to variations in orbital and inertial parameters alike. As per novel aspect concern, a generalized linear state-space and simplified expression for an analytical solution are derived for a momentum-biased asymmetric satellite. Through analysis, observation is made that even in case of highly elliptical orbits, a single controller design could yield optimal results and the variation of angular rates on control output is minimal. Even in case of extreme variations in inertia matrix and orbital rates, the controller performs as intended and results promise the development of fast and robust controllers for nadir pointing spacecraft in elliptical orbits.
{"title":"Quaternion Based Optimal Controller for Momentum Biased Nadir Pointing Satellite","authors":"Salahudden, Praful Kumar, V. S. Dwivedi, D. Giri, A. Ghosh","doi":"10.1109/AERO47225.2020.9172570","DOIUrl":"https://doi.org/10.1109/AERO47225.2020.9172570","url":null,"abstract":"In this paper, a quaternion based linear quadratic controller (LQR) is designed for nadir pointing satellites. The stability of the proposed controller is proved for specified control input. Runge-Kutta (RK4) numerical scheme and constrained nonlinear optimization technique are adapted to perform the simulation for computation of optimal values of a gain matrix, control weighted matrix, error weighted matrix and Riccati matrix for designing LQR controller. Simulations are carried out for three categories of spacecraft's- nano, medium and large, showing quick response and high tolerance to variations in orbital and inertial parameters alike. As per novel aspect concern, a generalized linear state-space and simplified expression for an analytical solution are derived for a momentum-biased asymmetric satellite. Through analysis, observation is made that even in case of highly elliptical orbits, a single controller design could yield optimal results and the variation of angular rates on control output is minimal. Even in case of extreme variations in inertia matrix and orbital rates, the controller performs as intended and results promise the development of fast and robust controllers for nadir pointing spacecraft in elliptical orbits.","PeriodicalId":114560,"journal":{"name":"2020 IEEE Aerospace Conference","volume":"118 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128172839","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-03-01DOI: 10.1109/AERO47225.2020.9172341
J. McCrae, Christopher A. Rice, Steven T. Fiorino, S. Bose-Pillai, A. Archibald
Wave optics were used to simulate a dual beacon Hartmann Turbulence Sensor (HTS). The system simulated was used experimentally to measure turbulence profiles. These simulations were intended to help explain differences between the experimental results and theoretical predictions. The theoretically predicted results presume weak turbulence, a Kolmogorov power spectrum for the turbulence, and a geometric optics derived weighting of the turbulence along the path. The simulations carried out used a modified von Kármán spectrum, with finite inner and outer scales, so the effects of these scales could be readily studied. A number of interesting results were obtained. The simulations resulted in lower tilt variances in the HTS subapertures than expected, but this had little end effect on the turbulence profiles produced. The effect of the inner and outer scales on this point will be discussed. The profiling technique proved to be powerful enough to sometimes resolve individual phase screens used in simulation. While this result is very interesting, it points to the challenges in simulating a system like this, rather than any difference between theory and experiment. Finally, while the geometric optics presumption is seen as ignoring diffraction, no conclusion on the differences between theory and experiment (or simulation) based upon this point was made. The simulations concentrated on simulating an actual HTS system with a 32 × 32 subaperture array on a 16″ telescope at a 1 km range.
{"title":"Wave Optics Simulations of a Dual Beacon Hartmann Turbulence Sensor","authors":"J. McCrae, Christopher A. Rice, Steven T. Fiorino, S. Bose-Pillai, A. Archibald","doi":"10.1109/AERO47225.2020.9172341","DOIUrl":"https://doi.org/10.1109/AERO47225.2020.9172341","url":null,"abstract":"Wave optics were used to simulate a dual beacon Hartmann Turbulence Sensor (HTS). The system simulated was used experimentally to measure turbulence profiles. These simulations were intended to help explain differences between the experimental results and theoretical predictions. The theoretically predicted results presume weak turbulence, a Kolmogorov power spectrum for the turbulence, and a geometric optics derived weighting of the turbulence along the path. The simulations carried out used a modified von Kármán spectrum, with finite inner and outer scales, so the effects of these scales could be readily studied. A number of interesting results were obtained. The simulations resulted in lower tilt variances in the HTS subapertures than expected, but this had little end effect on the turbulence profiles produced. The effect of the inner and outer scales on this point will be discussed. The profiling technique proved to be powerful enough to sometimes resolve individual phase screens used in simulation. While this result is very interesting, it points to the challenges in simulating a system like this, rather than any difference between theory and experiment. Finally, while the geometric optics presumption is seen as ignoring diffraction, no conclusion on the differences between theory and experiment (or simulation) based upon this point was made. The simulations concentrated on simulating an actual HTS system with a 32 × 32 subaperture array on a 16″ telescope at a 1 km range.","PeriodicalId":114560,"journal":{"name":"2020 IEEE Aerospace Conference","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125460986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-03-01DOI: 10.1109/AERO47225.2020.9172323
Marshall Smith, D. Craig, Nicole B. Herrmann, Erin Mahoney, Jonathan Krezel, N. McIntyre, K. Goodliff
NASA is developing a two-phased approach to quickly return humans to the Moon and establish a sustainable presence in orbit and on the surface. The two phases run in parallel, and both have already begun, with selection of the first Gateway element, the Power and Propulsion Element, solicitation activities focused on an American-built, industry-provided Human Landing System, and discussions with industry and international partners about potential opportunities for collaboration. Phase 1 is driven exclusively by the administration's priority to land the first woman and the next man on the lunar South Pole by 2024. In this phase, NASA and its partners will develop and deploy two Gateway components: the Power and Propulsion Element (PPE) that will launch in 2022, and the Habitation and Logistics Outpost (HALO), a minimal habitation capability) that will launch in 2023. Both will launch on commercial rockets, as will Gateway logistics deliveries to outfit the ship and provide supplies for surface expeditions. This initial Gateway configuration represents the beginning of its capability buildup, and the primary components required to support the first human expedition to the lunar South Pole. NASA's baseline reference approach for human expeditions on the surface is for Human Landing Systems to aggregate and dock to the Gateway, then deploy to the lunar South Pole with two astronauts aboard. Phase 2 is focused on advancing the technologies that will foster a sustainable presence on and around the Moon - a lasting and productive presence enabled by reusable systems, access for a diverse body of contributing partners, and repeatable trips to multiple destinations across the lunar surface. In this Phase, we will advance sustainable systems to make surface expeditions more repeatable and affordable. While the Gateway is the first of its kind to be funded, the concept has been proposed for decades as a necessary and foundational capability for a sustainable return to the Moon, and a port for vehicles embarking to farther destinations. It supports every tenet of Space Policy Directive-1 and the infrastructure it provides is critical to an accelerated return to the Moon, and access to more parts of the Moon than ever before. The Gateway also provides a unique platform to conduct cross-discipline science. Science instruments, both internal and external to the Gateway, have the potential to reveal new findings in space science, Earth science, and biological research data from deep space. Additionally, the broad science community will be able to utilize the communications and data relay capabilities of the Gateway, beginning with the PPE in Phase 1. This paper will outline the cross-discipline activities NASA is currently conducting, and those the agency anticipates conducting in the future to successfully implement Phases 1 and 2 in the lunar vicinity, all while preparing for humanity's next giant leap: Mars.
{"title":"The Artemis Program: An Overview of NASA's Activities to Return Humans to the Moon","authors":"Marshall Smith, D. Craig, Nicole B. Herrmann, Erin Mahoney, Jonathan Krezel, N. McIntyre, K. Goodliff","doi":"10.1109/AERO47225.2020.9172323","DOIUrl":"https://doi.org/10.1109/AERO47225.2020.9172323","url":null,"abstract":"NASA is developing a two-phased approach to quickly return humans to the Moon and establish a sustainable presence in orbit and on the surface. The two phases run in parallel, and both have already begun, with selection of the first Gateway element, the Power and Propulsion Element, solicitation activities focused on an American-built, industry-provided Human Landing System, and discussions with industry and international partners about potential opportunities for collaboration. Phase 1 is driven exclusively by the administration's priority to land the first woman and the next man on the lunar South Pole by 2024. In this phase, NASA and its partners will develop and deploy two Gateway components: the Power and Propulsion Element (PPE) that will launch in 2022, and the Habitation and Logistics Outpost (HALO), a minimal habitation capability) that will launch in 2023. Both will launch on commercial rockets, as will Gateway logistics deliveries to outfit the ship and provide supplies for surface expeditions. This initial Gateway configuration represents the beginning of its capability buildup, and the primary components required to support the first human expedition to the lunar South Pole. NASA's baseline reference approach for human expeditions on the surface is for Human Landing Systems to aggregate and dock to the Gateway, then deploy to the lunar South Pole with two astronauts aboard. Phase 2 is focused on advancing the technologies that will foster a sustainable presence on and around the Moon - a lasting and productive presence enabled by reusable systems, access for a diverse body of contributing partners, and repeatable trips to multiple destinations across the lunar surface. In this Phase, we will advance sustainable systems to make surface expeditions more repeatable and affordable. While the Gateway is the first of its kind to be funded, the concept has been proposed for decades as a necessary and foundational capability for a sustainable return to the Moon, and a port for vehicles embarking to farther destinations. It supports every tenet of Space Policy Directive-1 and the infrastructure it provides is critical to an accelerated return to the Moon, and access to more parts of the Moon than ever before. The Gateway also provides a unique platform to conduct cross-discipline science. Science instruments, both internal and external to the Gateway, have the potential to reveal new findings in space science, Earth science, and biological research data from deep space. Additionally, the broad science community will be able to utilize the communications and data relay capabilities of the Gateway, beginning with the PPE in Phase 1. This paper will outline the cross-discipline activities NASA is currently conducting, and those the agency anticipates conducting in the future to successfully implement Phases 1 and 2 in the lunar vicinity, all while preparing for humanity's next giant leap: Mars.","PeriodicalId":114560,"journal":{"name":"2020 IEEE Aerospace Conference","volume":"2010 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125610283","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-03-01DOI: 10.1109/AERO47225.2020.9172280
M. Kuklewski, S. Hanasz, G. Kasprowicz, Marcin Bieda
This paper presents a concept of the universal COTS-based Payload Carrier for new a microsatellite platform designed in compliance with the SpaceVPX (VITA 78.0) standard. Card functionality can be extended by adding VITA 57.1 FMC Mezzanine cards and therefore cover a wide spectrum of applications, which can be prototyped on off-the-shelf FMC evaluation boards. Selected assumptions of the design, which originate from a minimum 2-year-long mission on LEO and the SpaceVPX standard, are described in the introduction. Further, they are followed by a detailed description of selected components and proposed software required for reliable operation in the space environment. Finally, examples of applications such as communication data link layer processor implemented according to CCSDS standard, DSP processor for Software-Defined-Radio, and interface for dedicated payload computer are described.
{"title":"Universal COTS-Based SpaceVPX Payload Carrier for LEO Application","authors":"M. Kuklewski, S. Hanasz, G. Kasprowicz, Marcin Bieda","doi":"10.1109/AERO47225.2020.9172280","DOIUrl":"https://doi.org/10.1109/AERO47225.2020.9172280","url":null,"abstract":"This paper presents a concept of the universal COTS-based Payload Carrier for new a microsatellite platform designed in compliance with the SpaceVPX (VITA 78.0) standard. Card functionality can be extended by adding VITA 57.1 FMC Mezzanine cards and therefore cover a wide spectrum of applications, which can be prototyped on off-the-shelf FMC evaluation boards. Selected assumptions of the design, which originate from a minimum 2-year-long mission on LEO and the SpaceVPX standard, are described in the introduction. Further, they are followed by a detailed description of selected components and proposed software required for reliable operation in the space environment. Finally, examples of applications such as communication data link layer processor implemented according to CCSDS standard, DSP processor for Software-Defined-Radio, and interface for dedicated payload computer are described.","PeriodicalId":114560,"journal":{"name":"2020 IEEE Aerospace Conference","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125977585","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-03-01DOI: 10.1109/AERO47225.2020.9172657
Young-Young Shen, Justin T. Miller, A. Anderson
Improving the design of spacesuits to reduce the rate of musculoskeletal injury to the wearer proves challenging due to the inability to observe human motion inside the suit. Past efforts have investigated the use of wearable inertial sensors to observe the motion of the wearer relative to the suit. However, none of these investigated the potential for the sensors themselves to interfere with human motion inside the suit. Additionally, these past systems were found to fail frequently in the harsh in-suit environment. The authors are developing a new in-suit wearable inertial sensor system in order to address the shortcomings faced by previous efforts. The current work describes two test campaigns to evaluate the comfort, mobility, and durability of the new system. Methods and data analysis plans are presented for each test campaign along with pilot study results for the comfort and mobility tests. These tests serve not only to provide verification of the performance of the new system, but also have the potential to allow conclusions to be made about past work using similar devices. The work advances the development of a reliable tool for observing human motion inside the spacesuit, which facilitates the design of safer suits that will be needed for planetary extravehicular activity.
{"title":"Comfort, Mobility, and Durability Assessment of a Wearable IMU System for EVA Suits","authors":"Young-Young Shen, Justin T. Miller, A. Anderson","doi":"10.1109/AERO47225.2020.9172657","DOIUrl":"https://doi.org/10.1109/AERO47225.2020.9172657","url":null,"abstract":"Improving the design of spacesuits to reduce the rate of musculoskeletal injury to the wearer proves challenging due to the inability to observe human motion inside the suit. Past efforts have investigated the use of wearable inertial sensors to observe the motion of the wearer relative to the suit. However, none of these investigated the potential for the sensors themselves to interfere with human motion inside the suit. Additionally, these past systems were found to fail frequently in the harsh in-suit environment. The authors are developing a new in-suit wearable inertial sensor system in order to address the shortcomings faced by previous efforts. The current work describes two test campaigns to evaluate the comfort, mobility, and durability of the new system. Methods and data analysis plans are presented for each test campaign along with pilot study results for the comfort and mobility tests. These tests serve not only to provide verification of the performance of the new system, but also have the potential to allow conclusions to be made about past work using similar devices. The work advances the development of a reliable tool for observing human motion inside the spacesuit, which facilitates the design of safer suits that will be needed for planetary extravehicular activity.","PeriodicalId":114560,"journal":{"name":"2020 IEEE Aerospace Conference","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127923651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-03-01DOI: 10.1109/AERO47225.2020.9172608
Thomas G. Ivanco, Donald F. Keller, Jennifer L. Pinkerton
A launch vehicle ground-wind-loads program is underway at the NASA Langley Transonic Dynamics Tunnel. The objectives are to quantify key aerodynamic and structural characteristics that impact the occurrence of large wind-induced oscillations of a launch vehicle when exposed to ground winds prior to launch. Of particular interest is the dynamic response of a launch vehicle when a von Kármán vortex street forms in the wake of the vehicle resulting in quasiperiodic lift and drag forces. Vehicle response to these quasiperiodic forces can become quite large when the frequency of vortex shedding nears that of a lowly-damped structural mode thereby exciting a resonant response. Wind approaching the vehicle can be characterized by a varying speed with height and turbulence content. The combination of both the varying speed and turbulence content is referred to herein as the atmospheric boundary-layer. The importance of the atmospheric boundary-layer upon launch vehicle wind-induced oscillation response has long been questioned, and its effects are not well understood. Although there are several facilities around the world dedicated to replicating atmospheric boundary layers, the development of such a boundary layer in a wind tunnel capable of producing flight-representative Reynolds numbers for aeroelastically-scaled launch vehicle models has only recently been accomplished. The NASA Langley Transonic Dynamics Tunnel is capable of simulating flight-representative Reynolds numbers of launch vehicles on the pad and is uniquely capable of replicating many fluid-structure scaling parameters typical of aeroelastic tests. Recent test efforts successfully developed representative atmospheric boundary-layers for three launch sites in the Transonic Dynamics Tunnel, thereby allowing all known aerodynamic and fluid-structure coupling parameters to be simultaneously simulated for those sites. Dynamic aeroelastically-scaled models representative of typical large launch vehicles were constructed for testing. Aeroelastic scaling includes matching geometry, mode shapes, reduced frequencies, damping, running mass ratios, and running stiffness ratios. The models were tested in smooth uniform flow and then immersed in the atmospheric boundary-layer for comparison of these effects. Dynamic data were acquired measuring unsteady pressure, acceleration, and base bending moment. It was discovered that peak dynamic loads resulting from resonant wind-induced oscillation response are similar when acquired in either smooth uniform flow or an atmospheric boundary-layer. This indicates that resonant lock-in events are minimally impacted by representative turbulence and/or wind profile. Alternately, nonresonant wind-induced oscillation response events are stronger when acquired in an atmospheric boundary-layer. This indicates that a lowly-damped structural response will increase when exposed to an increased magnitude of random excitation, which is consistent with historical comparison
{"title":"Investigation of Atmospheric Boundary-Layer Effects on Launch-Vehicle Ground Wind Loads","authors":"Thomas G. Ivanco, Donald F. Keller, Jennifer L. Pinkerton","doi":"10.1109/AERO47225.2020.9172608","DOIUrl":"https://doi.org/10.1109/AERO47225.2020.9172608","url":null,"abstract":"A launch vehicle ground-wind-loads program is underway at the NASA Langley Transonic Dynamics Tunnel. The objectives are to quantify key aerodynamic and structural characteristics that impact the occurrence of large wind-induced oscillations of a launch vehicle when exposed to ground winds prior to launch. Of particular interest is the dynamic response of a launch vehicle when a von Kármán vortex street forms in the wake of the vehicle resulting in quasiperiodic lift and drag forces. Vehicle response to these quasiperiodic forces can become quite large when the frequency of vortex shedding nears that of a lowly-damped structural mode thereby exciting a resonant response. Wind approaching the vehicle can be characterized by a varying speed with height and turbulence content. The combination of both the varying speed and turbulence content is referred to herein as the atmospheric boundary-layer. The importance of the atmospheric boundary-layer upon launch vehicle wind-induced oscillation response has long been questioned, and its effects are not well understood. Although there are several facilities around the world dedicated to replicating atmospheric boundary layers, the development of such a boundary layer in a wind tunnel capable of producing flight-representative Reynolds numbers for aeroelastically-scaled launch vehicle models has only recently been accomplished. The NASA Langley Transonic Dynamics Tunnel is capable of simulating flight-representative Reynolds numbers of launch vehicles on the pad and is uniquely capable of replicating many fluid-structure scaling parameters typical of aeroelastic tests. Recent test efforts successfully developed representative atmospheric boundary-layers for three launch sites in the Transonic Dynamics Tunnel, thereby allowing all known aerodynamic and fluid-structure coupling parameters to be simultaneously simulated for those sites. Dynamic aeroelastically-scaled models representative of typical large launch vehicles were constructed for testing. Aeroelastic scaling includes matching geometry, mode shapes, reduced frequencies, damping, running mass ratios, and running stiffness ratios. The models were tested in smooth uniform flow and then immersed in the atmospheric boundary-layer for comparison of these effects. Dynamic data were acquired measuring unsteady pressure, acceleration, and base bending moment. It was discovered that peak dynamic loads resulting from resonant wind-induced oscillation response are similar when acquired in either smooth uniform flow or an atmospheric boundary-layer. This indicates that resonant lock-in events are minimally impacted by representative turbulence and/or wind profile. Alternately, nonresonant wind-induced oscillation response events are stronger when acquired in an atmospheric boundary-layer. This indicates that a lowly-damped structural response will increase when exposed to an increased magnitude of random excitation, which is consistent with historical comparison","PeriodicalId":114560,"journal":{"name":"2020 IEEE Aerospace Conference","volume":"101 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132078955","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-03-01DOI: 10.1109/AERO47225.2020.9172664
T. Cohen, D. Lees, D. Lim, N. Raineault, M. Deans
NASA Ames' Exploration Ground Data Systems (xGDS) supports rapid scientific decision making by synchronizing information in time and space, including video and still images, scientific instrument data, and science and operations notes in geographic and temporal context. We have deployed xGDS at multiple NASA field analog missions over the past decade. In the last two years, we have participated in SUBSEA, a multi-institution collaborative project*. SUBSEA used the research ship E/V Nautilus along with its two remotely operated vehicles (ROVs), Hercules and Argus, to explore deep ocean volcanic vents as an analog for ocean worlds (e.g. Enceladus). This work allowed us to compare the existing oceanographic operations methods and technologies used for ocean exploration with corresponding tools and approaches developed and used at NASA. In the first year of SUBSEA we observed existing remote science operations from the Inner Space Center (ISC)**. In the second year, we deployed xGDS at ISC to complement existing capabilities with xGDS tools designed to support remote Nautilus science operations from the ISC. During operations, video, ROV position and instrument telemetry were streamed from the ship to the ISC. As the science team watched dive operations, they could annotate the data with observations that were relevant to their work domain. Later, the team members could review the data at their own pace to collaboratively develop a dive plan for the next day, which had to be delivered on a fixed daily schedule. The opportunity to compare operations under different conditions enabled us to make several key observations about conducting remote science and planning operations efficiently: (i) Reviewing data collaboratively and interactively with temporal and spatial context was critical for the remote science team's ability to plan dive operations on the Nautilus. (ii) Science team members were actively engaged with the remote dive operations because they could interact with the collected data and visualize it as they desired. (iii) Being able to replay past events at accelerated speeds, and jump to points in time and spaced based on search results, provided efficient access to critical points of interest in a massive volume of data, so the remote science team could deliver plans on time. * SUBSEA (Systematic Underwater Biogeochemical Science and Exploration Analog) is a multi-institution collaboration supported by NASA, NOAA's Office of Exploration Research (OER), the Ocean Exploration Trust (OET) and the University of Rhode Island's Graduate School of Oceanography (GSO). ** ISC is GSO's telepresence operations facility.
{"title":"Conducting efficient remote science and planning operations for ocean exploration using Exploration Ground Data Systems (xGDS)","authors":"T. Cohen, D. Lees, D. Lim, N. Raineault, M. Deans","doi":"10.1109/AERO47225.2020.9172664","DOIUrl":"https://doi.org/10.1109/AERO47225.2020.9172664","url":null,"abstract":"NASA Ames' Exploration Ground Data Systems (xGDS) supports rapid scientific decision making by synchronizing information in time and space, including video and still images, scientific instrument data, and science and operations notes in geographic and temporal context. We have deployed xGDS at multiple NASA field analog missions over the past decade. In the last two years, we have participated in SUBSEA, a multi-institution collaborative project*. SUBSEA used the research ship E/V Nautilus along with its two remotely operated vehicles (ROVs), Hercules and Argus, to explore deep ocean volcanic vents as an analog for ocean worlds (e.g. Enceladus). This work allowed us to compare the existing oceanographic operations methods and technologies used for ocean exploration with corresponding tools and approaches developed and used at NASA. In the first year of SUBSEA we observed existing remote science operations from the Inner Space Center (ISC)**. In the second year, we deployed xGDS at ISC to complement existing capabilities with xGDS tools designed to support remote Nautilus science operations from the ISC. During operations, video, ROV position and instrument telemetry were streamed from the ship to the ISC. As the science team watched dive operations, they could annotate the data with observations that were relevant to their work domain. Later, the team members could review the data at their own pace to collaboratively develop a dive plan for the next day, which had to be delivered on a fixed daily schedule. The opportunity to compare operations under different conditions enabled us to make several key observations about conducting remote science and planning operations efficiently: (i) Reviewing data collaboratively and interactively with temporal and spatial context was critical for the remote science team's ability to plan dive operations on the Nautilus. (ii) Science team members were actively engaged with the remote dive operations because they could interact with the collected data and visualize it as they desired. (iii) Being able to replay past events at accelerated speeds, and jump to points in time and spaced based on search results, provided efficient access to critical points of interest in a massive volume of data, so the remote science team could deliver plans on time. * SUBSEA (Systematic Underwater Biogeochemical Science and Exploration Analog) is a multi-institution collaboration supported by NASA, NOAA's Office of Exploration Research (OER), the Ocean Exploration Trust (OET) and the University of Rhode Island's Graduate School of Oceanography (GSO). ** ISC is GSO's telepresence operations facility.","PeriodicalId":114560,"journal":{"name":"2020 IEEE Aerospace Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130167547","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-03-01DOI: 10.1109/AERO47225.2020.9172563
C. Maple, M. Bradbury, Hu Yuan, M. Farrell, C. Dixon, M. Fisher, U. Atmaca
Modern space systems are increasing in complexity. The advent of the Internet of Space Things, coupled with the commercialisation of space has resulted in an ecosystem that is difficult to control and brings about new security challenges. In such critical systems, it is common to conduct verification strategies to ensure that the underpinning software is correct. Formal verification is achieved by modelling the system and verifying that the model obeys particular functional and safety properties. Many connected systems are now the target of a variety of threat actors attempting to realise different goals. Threat modelling is the approach employed to analyse and manage the threats from adversaries. Common practice is that these two approaches are conducted independently of one another. In this paper, we argue that the two should be mutually informed, and describe a methodology for security-minded formal verification that combines these analysis techniques. This approach will streamline the development process and give a more formal grounding to the security properties identified during threat analysis.
{"title":"Security-Minded Verification of Space Systems","authors":"C. Maple, M. Bradbury, Hu Yuan, M. Farrell, C. Dixon, M. Fisher, U. Atmaca","doi":"10.1109/AERO47225.2020.9172563","DOIUrl":"https://doi.org/10.1109/AERO47225.2020.9172563","url":null,"abstract":"Modern space systems are increasing in complexity. The advent of the Internet of Space Things, coupled with the commercialisation of space has resulted in an ecosystem that is difficult to control and brings about new security challenges. In such critical systems, it is common to conduct verification strategies to ensure that the underpinning software is correct. Formal verification is achieved by modelling the system and verifying that the model obeys particular functional and safety properties. Many connected systems are now the target of a variety of threat actors attempting to realise different goals. Threat modelling is the approach employed to analyse and manage the threats from adversaries. Common practice is that these two approaches are conducted independently of one another. In this paper, we argue that the two should be mutually informed, and describe a methodology for security-minded formal verification that combines these analysis techniques. This approach will streamline the development process and give a more formal grounding to the security properties identified during threat analysis.","PeriodicalId":114560,"journal":{"name":"2020 IEEE Aerospace Conference","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130251902","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-03-01DOI: 10.1109/AERO47225.2020.9172809
Jeremiah Crane, R. Morgenstern, E. Parrott
Model-Based Systems Engineering (MBSE) can be a challenge when there is only one modeler and one model involved. For the Gateway Program, due to its unique acquisition approach, the modeling efforts involve multiple NASA centers with each developing their own models. Every additional model to be integrated compounds the difficulties, necessitating stronger ontologies and explicitly defined interfaces between models. To help facilitate this integration, a vision of collaboration between centers is in its beginning stages. This vision includes looking at models as systems themselves and developing their own use cases, requirements and interfaces between each of them. The goal of this paper is to share the Gateway Program's cross-center vision for model collaboration, the lessons learned in developing and implementing that vision for the various system engineering products needed to satisfy life cycle review criteria and how treating models as systems helped in these efforts.
{"title":"Vision for Cross-Center MSBE Collaboration on the Gateway Program","authors":"Jeremiah Crane, R. Morgenstern, E. Parrott","doi":"10.1109/AERO47225.2020.9172809","DOIUrl":"https://doi.org/10.1109/AERO47225.2020.9172809","url":null,"abstract":"Model-Based Systems Engineering (MBSE) can be a challenge when there is only one modeler and one model involved. For the Gateway Program, due to its unique acquisition approach, the modeling efforts involve multiple NASA centers with each developing their own models. Every additional model to be integrated compounds the difficulties, necessitating stronger ontologies and explicitly defined interfaces between models. To help facilitate this integration, a vision of collaboration between centers is in its beginning stages. This vision includes looking at models as systems themselves and developing their own use cases, requirements and interfaces between each of them. The goal of this paper is to share the Gateway Program's cross-center vision for model collaboration, the lessons learned in developing and implementing that vision for the various system engineering products needed to satisfy life cycle review criteria and how treating models as systems helped in these efforts.","PeriodicalId":114560,"journal":{"name":"2020 IEEE Aerospace Conference","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130493061","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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