Pub Date : 2017-03-04DOI: 10.1109/AERO.2017.7943703
Elizabeth Heisler, E. Abel, Elizabeth A. Congdon, D. Eby
Solar Probe Plus (SPP) is a NASA mission that will go within ten Solar Radii of the sun. One of the crucial technologies in this system is the Thermal Protection System (TPS), which shields the spacecraft from the sun. The TPS is made up of carbon-foam sandwiched between two carbon-carbon panels, and is approximately eight feet in diameter and 4.5 inches thick. At its closest approach, the front surface of the TPS is expected to reach 1200°C, but the foam will dissipate the heat so the back surface will only be about 300°C. Solar Probe Plus is scheduled to launch in 2018, and the program is in the beginning stages of integration and testing. As part of the testing process, SPP's cooling system and the full spacecraft will undergo thermal tests. Radiation from the back of the TPS plays a large part in both of these systems thermal environment. To get the back surface of the TPS to 300°C, large amounts of energy needs to be put into the top of the TPS. However, there are not many thermal chambers that can accommodate the amount of energy required at the vacuum environment required to simulate space. It is also extremely risky to expose the flight hardware to that much energy. Instead, a Thermal Simulator will be used that mimics the thermal and geometric footprint of the bottom of the TPS. The Thermal Simulator is designed as an oven box, similar in size and shape to the flight TPS, which uses tubular heaters to heat a 32 mil thick aluminum bottom sheet. The heaters and bottom sheet are supported by a large stainless steel structure. The sides and top of the structure are blanketed using stainless steel sheets. To verify the concept, a miniature simulator was built and tested. Despite a successful trial simulator, there were difficulties extrapolating the design into a larger size. This paper will focus on the construction and testing of the full-sized simulator. After extensive structural and thermal analysis, the full simulator was fabricated and assembled. A thermal vacuum test was done at NASA Goddard Space Flight Center in chamber 238. At high vacuum, the bottom sheet was successfully brought to 250°C, 300°C, and 350°C with gradients of +/−30°C. Each temperature point was held for at least three hours after steady state was achieved. This simulator will be used in winter 2017 for the Integrated Thermal Vacuum Test, and again in the future for the full spacecraft test. By successfully executing the thermal system testing using GSE, we will prove that a full system can be validated using piecemeal testing.
{"title":"Full scale thermal simulator development for the solar probe plus thermal protection system","authors":"Elizabeth Heisler, E. Abel, Elizabeth A. Congdon, D. Eby","doi":"10.1109/AERO.2017.7943703","DOIUrl":"https://doi.org/10.1109/AERO.2017.7943703","url":null,"abstract":"Solar Probe Plus (SPP) is a NASA mission that will go within ten Solar Radii of the sun. One of the crucial technologies in this system is the Thermal Protection System (TPS), which shields the spacecraft from the sun. The TPS is made up of carbon-foam sandwiched between two carbon-carbon panels, and is approximately eight feet in diameter and 4.5 inches thick. At its closest approach, the front surface of the TPS is expected to reach 1200°C, but the foam will dissipate the heat so the back surface will only be about 300°C. Solar Probe Plus is scheduled to launch in 2018, and the program is in the beginning stages of integration and testing. As part of the testing process, SPP's cooling system and the full spacecraft will undergo thermal tests. Radiation from the back of the TPS plays a large part in both of these systems thermal environment. To get the back surface of the TPS to 300°C, large amounts of energy needs to be put into the top of the TPS. However, there are not many thermal chambers that can accommodate the amount of energy required at the vacuum environment required to simulate space. It is also extremely risky to expose the flight hardware to that much energy. Instead, a Thermal Simulator will be used that mimics the thermal and geometric footprint of the bottom of the TPS. The Thermal Simulator is designed as an oven box, similar in size and shape to the flight TPS, which uses tubular heaters to heat a 32 mil thick aluminum bottom sheet. The heaters and bottom sheet are supported by a large stainless steel structure. The sides and top of the structure are blanketed using stainless steel sheets. To verify the concept, a miniature simulator was built and tested. Despite a successful trial simulator, there were difficulties extrapolating the design into a larger size. This paper will focus on the construction and testing of the full-sized simulator. After extensive structural and thermal analysis, the full simulator was fabricated and assembled. A thermal vacuum test was done at NASA Goddard Space Flight Center in chamber 238. At high vacuum, the bottom sheet was successfully brought to 250°C, 300°C, and 350°C with gradients of +/−30°C. Each temperature point was held for at least three hours after steady state was achieved. This simulator will be used in winter 2017 for the Integrated Thermal Vacuum Test, and again in the future for the full spacecraft test. By successfully executing the thermal system testing using GSE, we will prove that a full system can be validated using piecemeal testing.","PeriodicalId":224475,"journal":{"name":"2017 IEEE Aerospace Conference","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127694808","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 : 2017-03-04DOI: 10.1109/AERO.2017.7943581
A. Qualls, J. Werner
As a result of recent increased interest in Mars exploration and other deep-space missions, the idea of a US Nuclear Thermal Propulsion (NTP) system has been rekindled, and the feasibility of such a program will be revisited. Making and qualifying an NTP fuel that meets mission performance requirements is an essential first step. Graphite fuels and ceramic metal (cermet) fuels are of particular interest since these fuels have shown significant advantages over other fuel types. This paper will address the history of NTP fuel fabrication technology as related to the Nuclear Engine for Rocket Vehicle Application, GE 710, and ANL nuclear fuel program, as well as recent efforts in recapturing heritage fuels and developing new NTP fuels. Substantial experimental databases and supporting documentation exists for the graphite composite fuel option. Some irradiation and high temperature test data is available for cermet fuels, but cermet fuels were never tested in prototypic NTP conditions. A first step in the development effort will be a fuel fabrication recapture effort to provide samples to show that the technology works and that the performance of the fuel is acceptable. Advances in fuel fabrication, materials processing, and coating technology are expected to improve and/or enhance future fuel development, maturation, and certification efforts. The current plan is to perform non-nuclear, separate-effects, and integrated tests to provide additional test data and insight into the capabilities of each fuel and to use that data to evaluate potential performance within an NTP engine stage.
{"title":"Steps in the development of nuclear thermal propulsion fuels","authors":"A. Qualls, J. Werner","doi":"10.1109/AERO.2017.7943581","DOIUrl":"https://doi.org/10.1109/AERO.2017.7943581","url":null,"abstract":"As a result of recent increased interest in Mars exploration and other deep-space missions, the idea of a US Nuclear Thermal Propulsion (NTP) system has been rekindled, and the feasibility of such a program will be revisited. Making and qualifying an NTP fuel that meets mission performance requirements is an essential first step. Graphite fuels and ceramic metal (cermet) fuels are of particular interest since these fuels have shown significant advantages over other fuel types. This paper will address the history of NTP fuel fabrication technology as related to the Nuclear Engine for Rocket Vehicle Application, GE 710, and ANL nuclear fuel program, as well as recent efforts in recapturing heritage fuels and developing new NTP fuels. Substantial experimental databases and supporting documentation exists for the graphite composite fuel option. Some irradiation and high temperature test data is available for cermet fuels, but cermet fuels were never tested in prototypic NTP conditions. A first step in the development effort will be a fuel fabrication recapture effort to provide samples to show that the technology works and that the performance of the fuel is acceptable. Advances in fuel fabrication, materials processing, and coating technology are expected to improve and/or enhance future fuel development, maturation, and certification efforts. The current plan is to perform non-nuclear, separate-effects, and integrated tests to provide additional test data and insight into the capabilities of each fuel and to use that data to evaluate potential performance within an NTP engine stage.","PeriodicalId":224475,"journal":{"name":"2017 IEEE Aerospace Conference","volume":"103 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128152127","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 : 2017-03-04DOI: 10.1109/AERO.2017.7943695
D. E. Betsy Pugel, J. Rummel, C. Conley
Much like keeping your teeth clean, where you brush away bio-films that your dentist calls “plaque,” there are various methods to clean spaceflight hardware of biological contamination, known as biological reduction processes. Different approaches clean your hardware's “teeth” in different ways and with different levels of effectiveness. We know that brushing at home with a simple toothbrush is convenient and has a different level of impact vs. getting your teeth cleaned at the dentist. In the same way, there are some approaches to biological reduction that may require simple tools or more complex implementation approaches (think about sonicating or just soaking your dentures, vs. brushing them). There are also some that are more effective for different degrees of cleanliness and still some that have materials compatibility concerns. In this article, we review known and NASA-certified approaches for biological reduction, pointing out materials compatibility concerns and areas where additional research is needed.
{"title":"Brushing your spacecraft's teeth: A review of biological reduction processes for planetary protection missions","authors":"D. E. Betsy Pugel, J. Rummel, C. Conley","doi":"10.1109/AERO.2017.7943695","DOIUrl":"https://doi.org/10.1109/AERO.2017.7943695","url":null,"abstract":"Much like keeping your teeth clean, where you brush away bio-films that your dentist calls “plaque,” there are various methods to clean spaceflight hardware of biological contamination, known as biological reduction processes. Different approaches clean your hardware's “teeth” in different ways and with different levels of effectiveness. We know that brushing at home with a simple toothbrush is convenient and has a different level of impact vs. getting your teeth cleaned at the dentist. In the same way, there are some approaches to biological reduction that may require simple tools or more complex implementation approaches (think about sonicating or just soaking your dentures, vs. brushing them). There are also some that are more effective for different degrees of cleanliness and still some that have materials compatibility concerns. In this article, we review known and NASA-certified approaches for biological reduction, pointing out materials compatibility concerns and areas where additional research is needed.","PeriodicalId":224475,"journal":{"name":"2017 IEEE Aerospace Conference","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132061540","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 : 2017-03-04DOI: 10.1109/AERO.2017.7943610
Peter Godart, Johannes Gross, R. Mukherjee, Wyatt Ubellacker
In this paper, we outline an approach for auto-generating real-time robotics control code from hierarchical state machines and hardware configurations encoded in Systems Modeling Language (SysML). We propose a software architecture that provides an abstract SysML layer with access to device state information and a set of primitive device commands, such as move_actuator and release_brake, allowing a user to build up a complete functional state machine directly in SysML. The SysML diagram is then exported to a standard SCXML file format and subsequently used to auto-generate hardware control code. Once this architecture is in place, the only explicit code elements that need to be written are the primitive device commands, which can be easily unit tested and reused across different systems. The motivation for this work was the need for a test bed that enables the rapid prototyping of mechanisms and control algorithms for a spacecraft that could ultimately be used for preparing Martian rock samples for their return to Earth. To this end, our software system was also designed to allow for the run-time specification of the hardware layout in SysML, with the hardware-level control functions kept agnostic to the specific parameters or communication bus of any particular device. Further, we outline a system for specifying both the state machine and hardware configuration in the MagicDraw IDE in such a way that the system can be simulated before any code is generated. The resultant software system is easy to debug, understand, and allows users to choose how much information is encoded as a visual or text-based representation.
{"title":"Generating real-time robotics control software from SysML","authors":"Peter Godart, Johannes Gross, R. Mukherjee, Wyatt Ubellacker","doi":"10.1109/AERO.2017.7943610","DOIUrl":"https://doi.org/10.1109/AERO.2017.7943610","url":null,"abstract":"In this paper, we outline an approach for auto-generating real-time robotics control code from hierarchical state machines and hardware configurations encoded in Systems Modeling Language (SysML). We propose a software architecture that provides an abstract SysML layer with access to device state information and a set of primitive device commands, such as move_actuator and release_brake, allowing a user to build up a complete functional state machine directly in SysML. The SysML diagram is then exported to a standard SCXML file format and subsequently used to auto-generate hardware control code. Once this architecture is in place, the only explicit code elements that need to be written are the primitive device commands, which can be easily unit tested and reused across different systems. The motivation for this work was the need for a test bed that enables the rapid prototyping of mechanisms and control algorithms for a spacecraft that could ultimately be used for preparing Martian rock samples for their return to Earth. To this end, our software system was also designed to allow for the run-time specification of the hardware layout in SysML, with the hardware-level control functions kept agnostic to the specific parameters or communication bus of any particular device. Further, we outline a system for specifying both the state machine and hardware configuration in the MagicDraw IDE in such a way that the system can be simulated before any code is generated. The resultant software system is easy to debug, understand, and allows users to choose how much information is encoded as a visual or text-based representation.","PeriodicalId":224475,"journal":{"name":"2017 IEEE Aerospace Conference","volume":"20 52","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132545757","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 : 2017-03-04DOI: 10.1109/AERO.2017.7943832
T. Bayer, B. Buffington, Jean-Francois Castet, Maddalena Jackson, Gene Y. Lee, K. Lewis, J. Kastner, K. Schimmels, K. Kirby
Europa, the fourth largest moon of Jupiter, is believed to be one of the best places in the solar system to look for extant life beyond Earth. The 2011 Planetary Decadal Survey, Vision and Voyages, states: “Because of this ocean's potential suitability for life, Europa is one of the most important targets in all of planetary science.” Exploring Europa to investigate its habitability is the goal of the planned Europa Mission. This exploration is intimately tied to understanding the three “ingredients” for life: liquid water, chemistry, and energy. The Europa Mission would investigate these ingredients by comprehensively exploring Europa's ice shell and liquid ocean interface, surface geology and surface composition to glean insight into the inner workings of this fascinating moon. In addition, a lander mission is seen as a possible future step, but current data about the Jovian radiation environment and about potential landing site hazards and potential safe landing zones is insufficient. Therefore an additional goal of the mission would be to characterize the radiation environment near Europa and investigate scientifically compelling sites for hazards, to inform a potential future landed mission. The Europa Mission envisions sending a flight system, consisting of a spacecraft equipped with a payload of NASA-selected scientific instruments, to execute numerous flybys of Europa while in Jupiter orbit. A key challenge is that the flight system must survive and operate in the intense Jovian radiation environment, which is especially harsh at Europa. The innovative design of this multiple-flyby tour is an enabling feature of this mission: by minimizing the time spent in the radiation environment the spacecraft complexity and cost has been significantly reduced compared to previous mission concepts. The spacecraft would launch from Kennedy Space Center (KSC), Cape Canaveral, Florida, USA, on a NASA supplied launch vehicle, no earlier than 2022. The formulation and implementation of the proposed mission is led by a joint Jet Propulsion Laboratory (JPL) and Applied Physics Laboratory (APL) Project team. In June 2015, NASA announced the selection of a highly capable suite of 10 scientific investigations to be flown on the Europa Mission. Since the announcement, the Europa Mission Team has updated the spacecraft design in order to fully accommodate this instrument suite — a significant challenge. After completing a successful System Requirements Review and Mission Definition Review in January of 2017, the project is currently transitioning from the concept development phase to the preliminary design phase of the mission. This paper will describe the progress of the Europa Mission since 2015, including maturation of the spacecraft design, requirements, system analyses, and mission trajectories.
{"title":"Europa mission update: Beyond payload selection","authors":"T. Bayer, B. Buffington, Jean-Francois Castet, Maddalena Jackson, Gene Y. Lee, K. Lewis, J. Kastner, K. Schimmels, K. Kirby","doi":"10.1109/AERO.2017.7943832","DOIUrl":"https://doi.org/10.1109/AERO.2017.7943832","url":null,"abstract":"Europa, the fourth largest moon of Jupiter, is believed to be one of the best places in the solar system to look for extant life beyond Earth. The 2011 Planetary Decadal Survey, Vision and Voyages, states: “Because of this ocean's potential suitability for life, Europa is one of the most important targets in all of planetary science.” Exploring Europa to investigate its habitability is the goal of the planned Europa Mission. This exploration is intimately tied to understanding the three “ingredients” for life: liquid water, chemistry, and energy. The Europa Mission would investigate these ingredients by comprehensively exploring Europa's ice shell and liquid ocean interface, surface geology and surface composition to glean insight into the inner workings of this fascinating moon. In addition, a lander mission is seen as a possible future step, but current data about the Jovian radiation environment and about potential landing site hazards and potential safe landing zones is insufficient. Therefore an additional goal of the mission would be to characterize the radiation environment near Europa and investigate scientifically compelling sites for hazards, to inform a potential future landed mission. The Europa Mission envisions sending a flight system, consisting of a spacecraft equipped with a payload of NASA-selected scientific instruments, to execute numerous flybys of Europa while in Jupiter orbit. A key challenge is that the flight system must survive and operate in the intense Jovian radiation environment, which is especially harsh at Europa. The innovative design of this multiple-flyby tour is an enabling feature of this mission: by minimizing the time spent in the radiation environment the spacecraft complexity and cost has been significantly reduced compared to previous mission concepts. The spacecraft would launch from Kennedy Space Center (KSC), Cape Canaveral, Florida, USA, on a NASA supplied launch vehicle, no earlier than 2022. The formulation and implementation of the proposed mission is led by a joint Jet Propulsion Laboratory (JPL) and Applied Physics Laboratory (APL) Project team. In June 2015, NASA announced the selection of a highly capable suite of 10 scientific investigations to be flown on the Europa Mission. Since the announcement, the Europa Mission Team has updated the spacecraft design in order to fully accommodate this instrument suite — a significant challenge. After completing a successful System Requirements Review and Mission Definition Review in January of 2017, the project is currently transitioning from the concept development phase to the preliminary design phase of the mission. This paper will describe the progress of the Europa Mission since 2015, including maturation of the spacecraft design, requirements, system analyses, and mission trajectories.","PeriodicalId":224475,"journal":{"name":"2017 IEEE Aerospace Conference","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127190454","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 : 2017-03-04DOI: 10.1109/AERO.2017.7943662
M. Simon, K. Latorella, John G. Martin, J. Cerro, R. Lepsch, S. Jefferies, K. Goodliff, D. Smitherman, C. McCleskey, C. Stromgren
This paper describes the recently developed point of departure design for a long duration, reusable Mars Transit Habitat, which was established during a 2016 NASA habitat design refinement activity supporting the definition of NASA's Evolvable Mars Campaign. As part of its development of sustainable human Mars mission concepts achievable in the 2030s, the Evolvable Mars Campaign has identified desired durations and mass/dimensional limits for long duration Mars habitat designs to enable the currently assumed solar electric and chemical transportation architectures. The Advanced Exploration Systems Mars Transit Habitat Refinement Activity brought together habitat subsystem design expertise from across NASA to develop an increased fidelity, consensus design for a transit habitat within these constraints. The resulting design and data (including a mass equipment list) contained in this paper are intended to help teams across the agency and potential commercial, academic, or international partners understand: 1) the current architecture/habitat guidelines and assumptions, 2) performance targets of such a habitat (particularly in mass, volume, and power), 3) the driving technology/capability developments and architectural solutions which are necessary for achieving these targets, and 4) mass reduction opportunities and research/design needs to inform the development of future research and proposals. Data presented includes: an overview of the habitat refinement activity including motivation and process when informative; full documentation of the baseline design guidelines and assumptions; detailed mass and volume breakdowns; a moderately detailed concept of operations; a preliminary interior layout design with rationale; a list of the required capabilities necessary to enable the desired mass; and identification of any worthwhile trades/analyses which could inform future habitat design efforts. As a whole, the data in the paper show that a transit habitat meeting the 43 metric tons launch mass/trans-Mars injection burn limits specified by the Evolvable Mars Campaign is achievable near the desired timeframe with moderate strategic investments including maintainable life support systems, repurposable structures and packaging, and lightweight exercise modalities. It also identifies operational and technological options to reduce this mass to less than 41 metric tons including staging of launch structure/packaging and alternate structural materials.
{"title":"NASA's advanced exploration systems Mars transit habitat refinement point of departure design","authors":"M. Simon, K. Latorella, John G. Martin, J. Cerro, R. Lepsch, S. Jefferies, K. Goodliff, D. Smitherman, C. McCleskey, C. Stromgren","doi":"10.1109/AERO.2017.7943662","DOIUrl":"https://doi.org/10.1109/AERO.2017.7943662","url":null,"abstract":"This paper describes the recently developed point of departure design for a long duration, reusable Mars Transit Habitat, which was established during a 2016 NASA habitat design refinement activity supporting the definition of NASA's Evolvable Mars Campaign. As part of its development of sustainable human Mars mission concepts achievable in the 2030s, the Evolvable Mars Campaign has identified desired durations and mass/dimensional limits for long duration Mars habitat designs to enable the currently assumed solar electric and chemical transportation architectures. The Advanced Exploration Systems Mars Transit Habitat Refinement Activity brought together habitat subsystem design expertise from across NASA to develop an increased fidelity, consensus design for a transit habitat within these constraints. The resulting design and data (including a mass equipment list) contained in this paper are intended to help teams across the agency and potential commercial, academic, or international partners understand: 1) the current architecture/habitat guidelines and assumptions, 2) performance targets of such a habitat (particularly in mass, volume, and power), 3) the driving technology/capability developments and architectural solutions which are necessary for achieving these targets, and 4) mass reduction opportunities and research/design needs to inform the development of future research and proposals. Data presented includes: an overview of the habitat refinement activity including motivation and process when informative; full documentation of the baseline design guidelines and assumptions; detailed mass and volume breakdowns; a moderately detailed concept of operations; a preliminary interior layout design with rationale; a list of the required capabilities necessary to enable the desired mass; and identification of any worthwhile trades/analyses which could inform future habitat design efforts. As a whole, the data in the paper show that a transit habitat meeting the 43 metric tons launch mass/trans-Mars injection burn limits specified by the Evolvable Mars Campaign is achievable near the desired timeframe with moderate strategic investments including maintainable life support systems, repurposable structures and packaging, and lightweight exercise modalities. It also identifies operational and technological options to reduce this mass to less than 41 metric tons including staging of launch structure/packaging and alternate structural materials.","PeriodicalId":224475,"journal":{"name":"2017 IEEE Aerospace Conference","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128380200","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 : 2017-03-04DOI: 10.1109/AERO.2017.7943887
Tara P. Polsgrove, H. Thomas, A. Cianciolo, Tim Collins, J. Samareh
Landing humans on Mars is one of NASA's long term goals. NASA's Evolvable Mars Campaign (EMC) is focused on evaluating architectural trade options to define the capabilities and elements needed to sustain human presence on the surface of Mars. The EMC study teams have considered a variety of in-space propulsion options and surface mission options. Understanding how these choices affect the performance of the lander will allow a balanced optimization of this complex system of systems problem. This paper presents the effects of mission and vehicle design options on lander mass and performance. Beginning with Earth launch, options include fairing size assumptions, co-manifesting elements with the lander, and Earth-Moon vicinity operations. Capturing into Mars orbit using either aerocapture or propulsive capture is assessed. For entry, descent, and landing both storable as well as oxygen and methane propellant combinations are considered, engine thrust level is assessed, and sensitivity to landed payload mass is presented. This paper focuses on lander designs using the Hypersonic Inflatable Aerodynamic Decelerators, one of several entry system technologies currently considered for human missions.
{"title":"Mission and design sensitivities for human Mars landers using Hypersonic Inflatable Aerodynamic Decelerators","authors":"Tara P. Polsgrove, H. Thomas, A. Cianciolo, Tim Collins, J. Samareh","doi":"10.1109/AERO.2017.7943887","DOIUrl":"https://doi.org/10.1109/AERO.2017.7943887","url":null,"abstract":"Landing humans on Mars is one of NASA's long term goals. NASA's Evolvable Mars Campaign (EMC) is focused on evaluating architectural trade options to define the capabilities and elements needed to sustain human presence on the surface of Mars. The EMC study teams have considered a variety of in-space propulsion options and surface mission options. Understanding how these choices affect the performance of the lander will allow a balanced optimization of this complex system of systems problem. This paper presents the effects of mission and vehicle design options on lander mass and performance. Beginning with Earth launch, options include fairing size assumptions, co-manifesting elements with the lander, and Earth-Moon vicinity operations. Capturing into Mars orbit using either aerocapture or propulsive capture is assessed. For entry, descent, and landing both storable as well as oxygen and methane propellant combinations are considered, engine thrust level is assessed, and sensitivity to landed payload mass is presented. This paper focuses on lander designs using the Hypersonic Inflatable Aerodynamic Decelerators, one of several entry system technologies currently considered for human missions.","PeriodicalId":224475,"journal":{"name":"2017 IEEE Aerospace Conference","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125333407","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 : 2017-03-04DOI: 10.1109/AERO.2017.7943614
Marina Andrade Lucena Holanda, R. A. Borges, Yago Henrique Melo Honda, Simone Battistini
This work presents the trajectory control system for the LAICAnSat-3 mission. The LAICAnSat project was established at the University of Brasilia for creating a low cost educational platform for conducting experiments at high and low altitudes. LAICAnSat previous stages include two launches of balloon-sats (LAICAnSat-1 and LAICAnSat-2). These two launches allowed the test of a preliminary system, which included a broad sensor suite (a high performance camera, temperature, pressure, humidity, UV light level, altitude, position, speed, heading, and acceleration sensors) and a communication and tracking system. The trajectory control of the LAICAnSat-3 is active during its descent phase. The goal of the guidance is to autonomously land the vehicle in a prescribed area. The directional control of the vehicle is provided by a paraglider, which is steered laterally by a servo motor that pulls the lines of the canopies. The system does not have a glide slope control, therefore the only controllable trajectory is the one on the horizontal plane; the vertical motion is assumed constrained by gravity and by the lift to drag ratio of the vehicle. Trajectory planning is based on a kinematic model of the vehicle and foresees the implementation of a series of trajectory paths of maximum control deflection that guarantees to remain in a bounded area. The reference heading is tracked by a PID controller, implemented in the on-board computer of the LAICAnSat. Simulations have been performed to assess the robustness of the designed controller to disturbances like wind gusts. The on-board computer is a board designed ad-hoc for this mission. It includes a micro-controller, environmental and inertial sensors, data storage capability, a multi-GNSS module, and the interfaces with the other subsystems of the vehicle. The multi-GNSS module provides position and heading information, which are used both on ground to track the flight and on-board to provide the feedback to the PID.
{"title":"Trajectory control system for the LAICAnSat-3 mission","authors":"Marina Andrade Lucena Holanda, R. A. Borges, Yago Henrique Melo Honda, Simone Battistini","doi":"10.1109/AERO.2017.7943614","DOIUrl":"https://doi.org/10.1109/AERO.2017.7943614","url":null,"abstract":"This work presents the trajectory control system for the LAICAnSat-3 mission. The LAICAnSat project was established at the University of Brasilia for creating a low cost educational platform for conducting experiments at high and low altitudes. LAICAnSat previous stages include two launches of balloon-sats (LAICAnSat-1 and LAICAnSat-2). These two launches allowed the test of a preliminary system, which included a broad sensor suite (a high performance camera, temperature, pressure, humidity, UV light level, altitude, position, speed, heading, and acceleration sensors) and a communication and tracking system. The trajectory control of the LAICAnSat-3 is active during its descent phase. The goal of the guidance is to autonomously land the vehicle in a prescribed area. The directional control of the vehicle is provided by a paraglider, which is steered laterally by a servo motor that pulls the lines of the canopies. The system does not have a glide slope control, therefore the only controllable trajectory is the one on the horizontal plane; the vertical motion is assumed constrained by gravity and by the lift to drag ratio of the vehicle. Trajectory planning is based on a kinematic model of the vehicle and foresees the implementation of a series of trajectory paths of maximum control deflection that guarantees to remain in a bounded area. The reference heading is tracked by a PID controller, implemented in the on-board computer of the LAICAnSat. Simulations have been performed to assess the robustness of the designed controller to disturbances like wind gusts. The on-board computer is a board designed ad-hoc for this mission. It includes a micro-controller, environmental and inertial sensors, data storage capability, a multi-GNSS module, and the interfaces with the other subsystems of the vehicle. The multi-GNSS module provides position and heading information, which are used both on ground to track the flight and on-board to provide the feedback to the PID.","PeriodicalId":224475,"journal":{"name":"2017 IEEE Aerospace Conference","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116951791","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 : 2017-03-04DOI: 10.1109/AERO.2017.7943727
S. Chappell, K. Beaton, Carolyn E Newton, T. Graff, K. Young, D. Coan, A. Abercromby, M. Gernhardt
NASA Extreme Environment Mission Operations (NEEMO) is an underwater spaceflight analog that provides a true mission-like operational environment for aquanauts living in the Aquarius undersea habitat for up to several weeks at a time. During these analog missions, aquanauts go out on multi-hour extravehicular activities (EVAs) and use buoyancy effects and added weight to simulate different gravity levels. The NEEMO 21 mission was undertaken in July of 2016. During this mission, the effects of several operations concepts (ConOps, defined as operational design elements that guide the organization and flow of hardware, personnel, communications, and data products through the course of a mission implementation) and a communication latency of 15 min oneway light time (OWLT) were studied in six aquanaut test subjects. These “Mars” aquanaut crewmembers conducted scientific exploration of the reef surrounding the Aquarius habitat while interacting with an “Earth-based” science team (ST) that was located topside. The ST provided guidance to the aquanauts throughout the EVAs across the 15 min communication latency. Exploration EVA traverses and timelines were planned in advance based on precursor data. During these 4-hr EVAs, the aquanauts completed science-related tasks, including pre-sampling surveys and marine-science-based sampling. Objective data included task completion times, total EVA time, crew idle time, translation time, ST-assimilation time (defined as time available for the ST to discuss, review, and act upon incoming data from the aquanauts). Subjective data included acceptability, simulation quality, and capability assessment ratings and associated comments. Additionally, feedback from both the crew and the ST were captured during the post-mission debrief. Each ConOps tested was found to provide advantages and disadvantages and it is likely that each will be used during the exploration of Mars. The choice of ConOps for Mars' EVAs will likely be dependent on the science objectives of that EVA balanced with the associated operational costs (such as human and rover transport cost).
{"title":"Integration of an Earth-based science team during human exploration of Mars","authors":"S. Chappell, K. Beaton, Carolyn E Newton, T. Graff, K. Young, D. Coan, A. Abercromby, M. Gernhardt","doi":"10.1109/AERO.2017.7943727","DOIUrl":"https://doi.org/10.1109/AERO.2017.7943727","url":null,"abstract":"NASA Extreme Environment Mission Operations (NEEMO) is an underwater spaceflight analog that provides a true mission-like operational environment for aquanauts living in the Aquarius undersea habitat for up to several weeks at a time. During these analog missions, aquanauts go out on multi-hour extravehicular activities (EVAs) and use buoyancy effects and added weight to simulate different gravity levels. The NEEMO 21 mission was undertaken in July of 2016. During this mission, the effects of several operations concepts (ConOps, defined as operational design elements that guide the organization and flow of hardware, personnel, communications, and data products through the course of a mission implementation) and a communication latency of 15 min oneway light time (OWLT) were studied in six aquanaut test subjects. These “Mars” aquanaut crewmembers conducted scientific exploration of the reef surrounding the Aquarius habitat while interacting with an “Earth-based” science team (ST) that was located topside. The ST provided guidance to the aquanauts throughout the EVAs across the 15 min communication latency. Exploration EVA traverses and timelines were planned in advance based on precursor data. During these 4-hr EVAs, the aquanauts completed science-related tasks, including pre-sampling surveys and marine-science-based sampling. Objective data included task completion times, total EVA time, crew idle time, translation time, ST-assimilation time (defined as time available for the ST to discuss, review, and act upon incoming data from the aquanauts). Subjective data included acceptability, simulation quality, and capability assessment ratings and associated comments. Additionally, feedback from both the crew and the ST were captured during the post-mission debrief. Each ConOps tested was found to provide advantages and disadvantages and it is likely that each will be used during the exploration of Mars. The choice of ConOps for Mars' EVAs will likely be dependent on the science objectives of that EVA balanced with the associated operational costs (such as human and rover transport cost).","PeriodicalId":224475,"journal":{"name":"2017 IEEE Aerospace Conference","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125559236","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 : 2017-03-04DOI: 10.1109/AERO.2017.7943878
M. Walker, F. Figueroa, Jaime Toro-Medina
The utility of Prognostics and Health Management (PHM) software capability applied to Autonomous Operations (AO) remains an active research area within aerospace applications. The ability to gain insight into which assets and subsystems are functioning properly, along with the derivation of confident predictions concerning future ability, reliability, and availability, are important enablers for making sound mission planning decisions. When coupled with software that fully supports mission planning and execution, an integrated solution can be developed that leverages state assessment and estimation for the purposes of delivering autonomous operations. The authors have been applying this integrated, model-based approach to the autonomous loading of cryogenic spacecraft propellants at Kennedy Space Center.
{"title":"PHM enabled autonomous propellant loading operations","authors":"M. Walker, F. Figueroa, Jaime Toro-Medina","doi":"10.1109/AERO.2017.7943878","DOIUrl":"https://doi.org/10.1109/AERO.2017.7943878","url":null,"abstract":"The utility of Prognostics and Health Management (PHM) software capability applied to Autonomous Operations (AO) remains an active research area within aerospace applications. The ability to gain insight into which assets and subsystems are functioning properly, along with the derivation of confident predictions concerning future ability, reliability, and availability, are important enablers for making sound mission planning decisions. When coupled with software that fully supports mission planning and execution, an integrated solution can be developed that leverages state assessment and estimation for the purposes of delivering autonomous operations. The authors have been applying this integrated, model-based approach to the autonomous loading of cryogenic spacecraft propellants at Kennedy Space Center.","PeriodicalId":224475,"journal":{"name":"2017 IEEE Aerospace Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128697179","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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