Pub Date : 2023-03-04DOI: 10.1109/AERO55745.2023.10115809
Aleksandra Markina-Khusid, G. Quinn
In June 2018, the Department of Defense (DoD) released its Digital Engineering (DE) Strategy. Among other goals, the DE approach aims to provide an enduring, authoritative source of truth (ASoT) and to incorporate technological innovation to improve the engineering practice. Leveraging an interoperability standard to integrate engineering and acquisition disciplines rather than specific tools can help the Government scale up Digital Engineering environments by allowing vendors to integrate their tools into the environments, supporting innovation by vendors and third parties including small businesses. Operational Analysis tools such as Advanced Framework for Simulation, Integration and Modeling (AFSIM) are used to evaluate effectiveness of System of Systems (SoS) Architectures in executing Find, Fix, Track, Target, Engage, Assess (F2T2EA) kill chain across a variety of Concepts of Operations (CONOPS) and environments. MITRE developed a standards-based approach to leverage Architecture models in setting up Operational Analysis runs based on the Open Services for Lifecycle Collaboration (OSLC) standard. This approach allows Government teams to explore trade space and place the proposed contractor solution in context informed by CONOPS and threats. The operational analysts can base their analysis on the authoritative source of truth for the system under design. As the Architecture changes, the Operational Analysis can be re-executed based on the updated model. The MITRE Corporation defined a new custom Operational Analysis Setup (OAS) domain as an extension to the OSLC standard, implemented an OAS provider for AFSIM input files, and developed an integration component to target any OAS provider with Architecture data. The integration component thus supports new Operational Analysis tools use in support of new forms of analysis based on the current ASoT. In this paper, we show an example of ingesting and using Architecture data from Cameo in AFSIM simulations via OSLC (including the new OAS domain).
{"title":"Integrating Architecture and Operational Analysis: A Standards-Based Approach","authors":"Aleksandra Markina-Khusid, G. Quinn","doi":"10.1109/AERO55745.2023.10115809","DOIUrl":"https://doi.org/10.1109/AERO55745.2023.10115809","url":null,"abstract":"In June 2018, the Department of Defense (DoD) released its Digital Engineering (DE) Strategy. Among other goals, the DE approach aims to provide an enduring, authoritative source of truth (ASoT) and to incorporate technological innovation to improve the engineering practice. Leveraging an interoperability standard to integrate engineering and acquisition disciplines rather than specific tools can help the Government scale up Digital Engineering environments by allowing vendors to integrate their tools into the environments, supporting innovation by vendors and third parties including small businesses. Operational Analysis tools such as Advanced Framework for Simulation, Integration and Modeling (AFSIM) are used to evaluate effectiveness of System of Systems (SoS) Architectures in executing Find, Fix, Track, Target, Engage, Assess (F2T2EA) kill chain across a variety of Concepts of Operations (CONOPS) and environments. MITRE developed a standards-based approach to leverage Architecture models in setting up Operational Analysis runs based on the Open Services for Lifecycle Collaboration (OSLC) standard. This approach allows Government teams to explore trade space and place the proposed contractor solution in context informed by CONOPS and threats. The operational analysts can base their analysis on the authoritative source of truth for the system under design. As the Architecture changes, the Operational Analysis can be re-executed based on the updated model. The MITRE Corporation defined a new custom Operational Analysis Setup (OAS) domain as an extension to the OSLC standard, implemented an OAS provider for AFSIM input files, and developed an integration component to target any OAS provider with Architecture data. The integration component thus supports new Operational Analysis tools use in support of new forms of analysis based on the current ASoT. In this paper, we show an example of ingesting and using Architecture data from Cameo in AFSIM simulations via OSLC (including the new OAS domain).","PeriodicalId":344285,"journal":{"name":"2023 IEEE Aerospace Conference","volume":"142 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126871424","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 : 2023-03-04DOI: 10.1109/AERO55745.2023.10116001
K. Kolcio, Maurice Prather
In order to achieve reliable autonomous operations, spacecraft need precise knowledge of their health state. These requirements can in part be met by model-based approaches to estimating health by continuously verifying nominal behavior and diagnosing off-nominal behavior. This paper describes the implementation and evaluation of the Model-based Off-Nominal State and Identification and Detection (MONSID®) system in the Air Force Research Laboratory's (AFRL's) ground-based environment for test and demonstration of spacecraft autonomy. The test bed is a 3 degree-of-freedom platform with spacecraft attitude control hardware and processors. During this effort we developed diagnostic models, integrated MONSID with the test bed processors using NASA's Core Flight System (cFS) framework, and evaluated system performance via a test campaign. The test campaign had over 40 test bed runs created from variations of realistic mission scenarios including nominal and injected fault cases. MONSID was running onboard a testbed processor and assessing the health of platform hardware. MONSID was able to verify nominal healthy operations as well successfully detect and accurately identify faults. There were three key highlights from the test campaign results. First, MONSID detected actual, unanticipated faults in the test bed hardware. Secondly, MONSID was able to effectively detect double faults, which is beyond the capabilities of most fault management systems. Finally, MONSID was able to detect faults quickly and correctly and with low false positive rates even with noisy data.
{"title":"Implementation and Evaluation of Model-based Health Assessment for Spacecraft Autonomy","authors":"K. Kolcio, Maurice Prather","doi":"10.1109/AERO55745.2023.10116001","DOIUrl":"https://doi.org/10.1109/AERO55745.2023.10116001","url":null,"abstract":"In order to achieve reliable autonomous operations, spacecraft need precise knowledge of their health state. These requirements can in part be met by model-based approaches to estimating health by continuously verifying nominal behavior and diagnosing off-nominal behavior. This paper describes the implementation and evaluation of the Model-based Off-Nominal State and Identification and Detection (MONSID®) system in the Air Force Research Laboratory's (AFRL's) ground-based environment for test and demonstration of spacecraft autonomy. The test bed is a 3 degree-of-freedom platform with spacecraft attitude control hardware and processors. During this effort we developed diagnostic models, integrated MONSID with the test bed processors using NASA's Core Flight System (cFS) framework, and evaluated system performance via a test campaign. The test campaign had over 40 test bed runs created from variations of realistic mission scenarios including nominal and injected fault cases. MONSID was running onboard a testbed processor and assessing the health of platform hardware. MONSID was able to verify nominal healthy operations as well successfully detect and accurately identify faults. There were three key highlights from the test campaign results. First, MONSID detected actual, unanticipated faults in the test bed hardware. Secondly, MONSID was able to effectively detect double faults, which is beyond the capabilities of most fault management systems. Finally, MONSID was able to detect faults quickly and correctly and with low false positive rates even with noisy data.","PeriodicalId":344285,"journal":{"name":"2023 IEEE Aerospace Conference","volume":"100 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114248037","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 : 2023-03-04DOI: 10.1109/AERO55745.2023.10115935
A. A. Rasna, C. Mohan
Airport surveillance activities using remote sensing images are challenging due to object variations largely affecting the geo-localization and object detection/segmentation tasks. Furthermore, the problem of localization is even larger due to scale variations. Traditionally image-based geo-referencing is accomplished by superimposing ground positioning system (GPS) location to the queried image. It is also observed both the query and the geo-tagged reference images are taken from the same ground view or aerial height in the case of remote sensing images. In our research, we intend to revisit the scale effect on object variability, by introducing the concept of geodesic representations along with image-matching networks. The architecture pipeline introduces a data processing layer wherein objects are geo-referenced to generate the metadata information. This metadata consists of three-dimensional data including the orientation information of the object. A regression task is added to the training set which leverages the metadata information. We use the gradient weighted class activation maps (Grad-CAM) to generate the activation maps and selection based on high threshold values for the pixel. The orientations and the locations are further calculated using the geodesic representations. The baseline architecture for local feature extraction uses a simple Siamese network with a ResNet backbone network. A NetVLAD layer is used to generate the global features. We also introduce a Geospatial attention network (GsAN) to aid in enhanced localization of objects. The dataset used for experiments consisted of CVUSA and our custom dataset providing airport runway views for different scales and arbitrary orientations. The performance evaluations focused on recall as a retrieval metric and comparing various loss functions. The performance metrics indicate a higher accuracy rate.
{"title":"Geodesic Based Image Matching Network for the Multi-scale Ground to Aerial Geo-localization","authors":"A. A. Rasna, C. Mohan","doi":"10.1109/AERO55745.2023.10115935","DOIUrl":"https://doi.org/10.1109/AERO55745.2023.10115935","url":null,"abstract":"Airport surveillance activities using remote sensing images are challenging due to object variations largely affecting the geo-localization and object detection/segmentation tasks. Furthermore, the problem of localization is even larger due to scale variations. Traditionally image-based geo-referencing is accomplished by superimposing ground positioning system (GPS) location to the queried image. It is also observed both the query and the geo-tagged reference images are taken from the same ground view or aerial height in the case of remote sensing images. In our research, we intend to revisit the scale effect on object variability, by introducing the concept of geodesic representations along with image-matching networks. The architecture pipeline introduces a data processing layer wherein objects are geo-referenced to generate the metadata information. This metadata consists of three-dimensional data including the orientation information of the object. A regression task is added to the training set which leverages the metadata information. We use the gradient weighted class activation maps (Grad-CAM) to generate the activation maps and selection based on high threshold values for the pixel. The orientations and the locations are further calculated using the geodesic representations. The baseline architecture for local feature extraction uses a simple Siamese network with a ResNet backbone network. A NetVLAD layer is used to generate the global features. We also introduce a Geospatial attention network (GsAN) to aid in enhanced localization of objects. The dataset used for experiments consisted of CVUSA and our custom dataset providing airport runway views for different scales and arbitrary orientations. The performance evaluations focused on recall as a retrieval metric and comparing various loss functions. The performance metrics indicate a higher accuracy rate.","PeriodicalId":344285,"journal":{"name":"2023 IEEE Aerospace Conference","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121085689","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 : 2023-03-04DOI: 10.1109/AERO55745.2023.10115831
C. Barklay, R. Hoffman, G. Pohl, Benjamin Williams
In 1964, a U.S. Navy Transit navigation satellite powered by a SNAP-9A Radioisotope Thermoelectric Generator (RTG) failed to achieve orbit, which resulted in the reentry and burnup of the RTG in the upper atmosphere. The subsequent atmospheric dispersion of the RTG's radioactive fuel was consistent with the RTG design philosophy of the time. However, the resulting global fallout and geographical distribution of the radioactive fuel led to a change in RTG design philosophy to complete fuel containment during all accident scenarios. This philosophy change necessitated a “free release” design architecture for the radioactive fuel encapsulations from the RTG during reentry, the survival of the individual encapsulations to the thermal pulse of reentry, and maintaining their integrity upon earth impact. All subsequent RTG designs for space applications have undergone rigorous analysis and testing to ensure conformity to these requirements. However, a “free release” design architecture becomes unviable if the mass of the individual encapsulations and their reentry aeroshell assemblies, coupled with their respective drag coefficients, results in a terminal velocity at Earth impact that potentially compromises the containment boundary of the radioactive fuel. These limiting boundary conditions necessitate consideration of potential alternative design approaches. One such approach is a “controlled reentry” design architecture for the RTG and its heat source assembly. This design approach includes an integral high-drag heat shield assembly capable of absorbing significant energy during Earth impact. Discussed are concept details, risks, trades, and a path forward.
{"title":"A Novel Design Approach for Post-Reentry Impact Survivability of Radioisotope Thermoelectric Generator Fuel","authors":"C. Barklay, R. Hoffman, G. Pohl, Benjamin Williams","doi":"10.1109/AERO55745.2023.10115831","DOIUrl":"https://doi.org/10.1109/AERO55745.2023.10115831","url":null,"abstract":"In 1964, a U.S. Navy Transit navigation satellite powered by a SNAP-9A Radioisotope Thermoelectric Generator (RTG) failed to achieve orbit, which resulted in the reentry and burnup of the RTG in the upper atmosphere. The subsequent atmospheric dispersion of the RTG's radioactive fuel was consistent with the RTG design philosophy of the time. However, the resulting global fallout and geographical distribution of the radioactive fuel led to a change in RTG design philosophy to complete fuel containment during all accident scenarios. This philosophy change necessitated a “free release” design architecture for the radioactive fuel encapsulations from the RTG during reentry, the survival of the individual encapsulations to the thermal pulse of reentry, and maintaining their integrity upon earth impact. All subsequent RTG designs for space applications have undergone rigorous analysis and testing to ensure conformity to these requirements. However, a “free release” design architecture becomes unviable if the mass of the individual encapsulations and their reentry aeroshell assemblies, coupled with their respective drag coefficients, results in a terminal velocity at Earth impact that potentially compromises the containment boundary of the radioactive fuel. These limiting boundary conditions necessitate consideration of potential alternative design approaches. One such approach is a “controlled reentry” design architecture for the RTG and its heat source assembly. This design approach includes an integral high-drag heat shield assembly capable of absorbing significant energy during Earth impact. Discussed are concept details, risks, trades, and a path forward.","PeriodicalId":344285,"journal":{"name":"2023 IEEE Aerospace Conference","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116082322","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 : 2023-03-04DOI: 10.1109/AERO55745.2023.10115954
William W. Jun, K. Cheung, E. Lightsey
Measurement differencing with GPS is an important method to reduce shared error between a user and a nearby reference station. It may also be crucial for position, navigation, and timing of lunar surface users. In conjunction with a relative positioning method, users on the surface of the Moon can utilize measurement differencing to achieve high accuracy, real-time positioning. This report analyzes improvements in surface positioning performance with single and double differenced measurements implemented with Joint Doppler and Ranging (JDR). JDR is a relative Doppler and range-based positioning method that can localize a surface user with a minimal navigation infrastructure. Previous analyses show JDR is effective at positioning lunar surface users near a reference station with as few as a single satellite. This analysis introduces updated implementations of JDR with the use of single and double differencing for both code-based range and Doppler measurements. These implementations include three total differencing methods with JDR along with comparisons of their positioning performance. Along with the known benefits provided by differencing code-based range measurements, differencing Doppler measurements enables cancellation effects of transmitted and local frequency offsets. This report performs a navigation simulation to calculate position estimation performance for a lunar surface user. This simulation assumes two Lunar Relay Satellites (LRS) in 12-hour frozen orbits as navigation nodes with a pre-existing reference station located on the south pole of the Moon. Modelled simulation errors include satellite ephemeris and reference station errors as Gaussian variables and satellite and user frequency errors as Brownian noise processes. These bias and noise sources are carefully distinguished between navigation nodes to ensure that the user and reference station see the proper shared error. Results show significant improvements in navigation performance with double differenced JDR (DD-JDR) relative to standard JDR and single differenced JDR (SD-JDR). DD-JDR can also reduce the effects of user local oscillator errors, including frequency offsets and noise. The reduction of these shared errors not only leads to improved positioning accuracy, but also results in lower timing hardware and receiver hardware requirements for the user. This greatly decreases cost and increases compatibility of JDR for autonomous lunar surface users.
{"title":"Improved Surface Positioning with Measurement Differences in Joint Doppler and Ranging","authors":"William W. Jun, K. Cheung, E. Lightsey","doi":"10.1109/AERO55745.2023.10115954","DOIUrl":"https://doi.org/10.1109/AERO55745.2023.10115954","url":null,"abstract":"Measurement differencing with GPS is an important method to reduce shared error between a user and a nearby reference station. It may also be crucial for position, navigation, and timing of lunar surface users. In conjunction with a relative positioning method, users on the surface of the Moon can utilize measurement differencing to achieve high accuracy, real-time positioning. This report analyzes improvements in surface positioning performance with single and double differenced measurements implemented with Joint Doppler and Ranging (JDR). JDR is a relative Doppler and range-based positioning method that can localize a surface user with a minimal navigation infrastructure. Previous analyses show JDR is effective at positioning lunar surface users near a reference station with as few as a single satellite. This analysis introduces updated implementations of JDR with the use of single and double differencing for both code-based range and Doppler measurements. These implementations include three total differencing methods with JDR along with comparisons of their positioning performance. Along with the known benefits provided by differencing code-based range measurements, differencing Doppler measurements enables cancellation effects of transmitted and local frequency offsets. This report performs a navigation simulation to calculate position estimation performance for a lunar surface user. This simulation assumes two Lunar Relay Satellites (LRS) in 12-hour frozen orbits as navigation nodes with a pre-existing reference station located on the south pole of the Moon. Modelled simulation errors include satellite ephemeris and reference station errors as Gaussian variables and satellite and user frequency errors as Brownian noise processes. These bias and noise sources are carefully distinguished between navigation nodes to ensure that the user and reference station see the proper shared error. Results show significant improvements in navigation performance with double differenced JDR (DD-JDR) relative to standard JDR and single differenced JDR (SD-JDR). DD-JDR can also reduce the effects of user local oscillator errors, including frequency offsets and noise. The reduction of these shared errors not only leads to improved positioning accuracy, but also results in lower timing hardware and receiver hardware requirements for the user. This greatly decreases cost and increases compatibility of JDR for autonomous lunar surface users.","PeriodicalId":344285,"journal":{"name":"2023 IEEE Aerospace Conference","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123849297","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 : 2023-03-04DOI: 10.1109/AERO55745.2023.10115834
Vedant, Patrick Haddox, James T. Allison
A new attitude control system (ACS) called Multifunctional Structures for Attitude Control (MSAC) utilizes structures onboard a spacecraft to provide active noise cancellation and large-angle slewing capabilities. Previous studies have detailed the system trades and physical and control designs that maximize the pointing performance of an MSAC system. As a result, the MSAC system can provide sub-milli-arc-second(mas)/nano-radian level pointing stability and accuracy. Traditional spacecraft design is formulated based on conventional spacecraft bus systems, of which conventional ACSs are a significant driver for the mass and volume of the spacecraft. MSAC relaxes these requirements and enables a new class of spacecraft missions. This paper details the new spacecraft architectures with large area-to-mass ratios that can be enabled using the MSAC system, such as solar sails, Disksats, ChipSats, etc. In addition to standalone spacecraft, MSAC can also be used to provide independent actuation capabilities to different subsystems onboard a spacecraft, such as self-steering antennas, solar panels, and thermal radiators. These new spacecraft busses and subsystems are made possible using MSAC, which can profoundly impact constellation mission development and deployment. Currently, MSAC exists as three main variants for use with different mission types and varying design complexity levels. This paper compares the different variants, and the control authority obtained using the different implementations. In addition to rotational control, MSAC also offers translational position control. These translational positioning capabilities are best at small scales (micrometer-level positioning). The position control can be utilized for internal translational active noise cancellation and formation flying missions that are sensitive to a spacecraft's position. Using the fine pointing and positioning accuracy and stability offered by MSAC can increase communication data rates for deep space optical communication, as well as enable missions such as distributed swarms and LISA.
{"title":"New Mission and Spacecraft Design Enabled Using MSAC","authors":"Vedant, Patrick Haddox, James T. Allison","doi":"10.1109/AERO55745.2023.10115834","DOIUrl":"https://doi.org/10.1109/AERO55745.2023.10115834","url":null,"abstract":"A new attitude control system (ACS) called Multifunctional Structures for Attitude Control (MSAC) utilizes structures onboard a spacecraft to provide active noise cancellation and large-angle slewing capabilities. Previous studies have detailed the system trades and physical and control designs that maximize the pointing performance of an MSAC system. As a result, the MSAC system can provide sub-milli-arc-second(mas)/nano-radian level pointing stability and accuracy. Traditional spacecraft design is formulated based on conventional spacecraft bus systems, of which conventional ACSs are a significant driver for the mass and volume of the spacecraft. MSAC relaxes these requirements and enables a new class of spacecraft missions. This paper details the new spacecraft architectures with large area-to-mass ratios that can be enabled using the MSAC system, such as solar sails, Disksats, ChipSats, etc. In addition to standalone spacecraft, MSAC can also be used to provide independent actuation capabilities to different subsystems onboard a spacecraft, such as self-steering antennas, solar panels, and thermal radiators. These new spacecraft busses and subsystems are made possible using MSAC, which can profoundly impact constellation mission development and deployment. Currently, MSAC exists as three main variants for use with different mission types and varying design complexity levels. This paper compares the different variants, and the control authority obtained using the different implementations. In addition to rotational control, MSAC also offers translational position control. These translational positioning capabilities are best at small scales (micrometer-level positioning). The position control can be utilized for internal translational active noise cancellation and formation flying missions that are sensitive to a spacecraft's position. Using the fine pointing and positioning accuracy and stability offered by MSAC can increase communication data rates for deep space optical communication, as well as enable missions such as distributed swarms and LISA.","PeriodicalId":344285,"journal":{"name":"2023 IEEE Aerospace Conference","volume":"358 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122813843","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 : 2023-03-04DOI: 10.1109/AERO55745.2023.10115843
Yanwu Ding, K. Pham
Classification of jamming signals in Global Navigation Satellite System (GNSS) has been explored recently using machine learning including Support Vector Machine (SVM) and Convolutional Neural Network (CNN) techniques. Identification of the jammer types helps to choose preferred methods which are more effective to remove such jammer. For example, adaptive frequency and time-domain filtering methods are commonly used for continuous-wave (CW) jammer mitigation; frequency-domain finite impulse response (FIR) or infinite impulse-response (IIR) filtering technique can put a notch in the jamming frequency. However, these techniques need primary information about jamming signal structure. Besides jamming, other interferences also cause receiver performance degradation including spoofing and obstructions in nearby environment such as mountains or buildings. This paper identifies these types of interferences besides the jammer types. Practical issues such as fading channels, Doppler frequencies, and phase shifts are considered for the satellite, jammer, and spoofer links.
{"title":"1 GNSS Interference Identification beyond Jammer Classification","authors":"Yanwu Ding, K. Pham","doi":"10.1109/AERO55745.2023.10115843","DOIUrl":"https://doi.org/10.1109/AERO55745.2023.10115843","url":null,"abstract":"Classification of jamming signals in Global Navigation Satellite System (GNSS) has been explored recently using machine learning including Support Vector Machine (SVM) and Convolutional Neural Network (CNN) techniques. Identification of the jammer types helps to choose preferred methods which are more effective to remove such jammer. For example, adaptive frequency and time-domain filtering methods are commonly used for continuous-wave (CW) jammer mitigation; frequency-domain finite impulse response (FIR) or infinite impulse-response (IIR) filtering technique can put a notch in the jamming frequency. However, these techniques need primary information about jamming signal structure. Besides jamming, other interferences also cause receiver performance degradation including spoofing and obstructions in nearby environment such as mountains or buildings. This paper identifies these types of interferences besides the jammer types. Practical issues such as fading channels, Doppler frequencies, and phase shifts are considered for the satellite, jammer, and spoofer links.","PeriodicalId":344285,"journal":{"name":"2023 IEEE Aerospace Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131159170","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 : 2023-03-04DOI: 10.1109/AERO55745.2023.10115798
J. Goodman
Lessons learned over a career are useful for identifying team development opportunities to ensure mission success and safety of flight. All human and robotic spaceflight is accomplished by teams of people working with technology. Spaceflight is about leading and organizing teams of people to solve engineering problems. Successful engineers identify lessons learned and best practices over the course of a career. These shape and guide how engineers make decisions, perform work, and interact with people. This paper details lessons learned from over thirty-six years of involvement in human space flight at the NASA Johnson Space Center, both in flight operations and spacecraft development.
{"title":"Opportunities for Team Development Based on Lessons Learned From Spaceflight Operations","authors":"J. Goodman","doi":"10.1109/AERO55745.2023.10115798","DOIUrl":"https://doi.org/10.1109/AERO55745.2023.10115798","url":null,"abstract":"Lessons learned over a career are useful for identifying team development opportunities to ensure mission success and safety of flight. All human and robotic spaceflight is accomplished by teams of people working with technology. Spaceflight is about leading and organizing teams of people to solve engineering problems. Successful engineers identify lessons learned and best practices over the course of a career. These shape and guide how engineers make decisions, perform work, and interact with people. This paper details lessons learned from over thirty-six years of involvement in human space flight at the NASA Johnson Space Center, both in flight operations and spacecraft development.","PeriodicalId":344285,"journal":{"name":"2023 IEEE Aerospace Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131167620","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 : 2023-03-04DOI: 10.1109/AERO55745.2023.10115678
M. Hakuba, C. Reynerson, M. Quadrelli, D. Wiese, C. McCullough, F. Landerer, G. Stephens
The direct measurement of Earth's radiative Energy Imbalance (EEI) from space is a challenge for state-of-the-art radiometric observing systems. Current spaceborne radiometers measure the individual shortwave (Solar incoming and Earth reflected solar radiation) and longwave (Earth emitted thermal radiation) components of Earth's energy balance with unprecedented stability, but with calibration errors that are too large to determine the absolute magnitude of global mean EEI or net radiative flux, respectively, as the components' residual. Best estimates of multi-year (2005–2020) EEI are derived from temporal changes in planetary heat content, predominantly ocean heat content, and amount to ~0.9 Wm−2. To monitor EEI directly from space, we propose an independent approach based on accelerometry that measures non-gravitational radial accelerations induced by radiation pressure. To provide requirements for a near-spherical “Space Balls” spacecraft and mission design, we develop a simulation environment using JPL's Mission Analysis, Operations, and Navigation Toolkit Environment (MONTE) software libraries and present-day radiative fluxes from the Clouds and Earth's Radiant Energy System (CERES). At its current initial stage, the toolset allows us to simulate accelerations acting on a spherical spacecraft due to solar radiation pressure, Earth's reflected shortwave (albedo) and emitted longwave radiation, as well as due to aerodynamic force. Induced accelerations as well as their sensitivity to mean orbit altitude and spacecraft absorptivity agree well with back-of the-envelope calculations and previous simulations that assess the role of radiation pressure accelerations for orbital drift. Future investigations will expand the MONTE-based simulation environment with additional shape and confounding force models. Preliminary simulations with an integrated spacecraft dynamics model suggest that the main confounding accelerations for a non-perfect, faceted sphere are related to Yarkovsky, aerodynamic force and relativistic effects, which will have to be mitigated to facilitate a high-accuracy EEI measurement from space.
{"title":"Measuring Earth's Energy Imbalance via Radiation Pressure Accelerations Experienced in Orbit: Initial Simulations for “Space Balls”","authors":"M. Hakuba, C. Reynerson, M. Quadrelli, D. Wiese, C. McCullough, F. Landerer, G. Stephens","doi":"10.1109/AERO55745.2023.10115678","DOIUrl":"https://doi.org/10.1109/AERO55745.2023.10115678","url":null,"abstract":"The direct measurement of Earth's radiative Energy Imbalance (EEI) from space is a challenge for state-of-the-art radiometric observing systems. Current spaceborne radiometers measure the individual shortwave (Solar incoming and Earth reflected solar radiation) and longwave (Earth emitted thermal radiation) components of Earth's energy balance with unprecedented stability, but with calibration errors that are too large to determine the absolute magnitude of global mean EEI or net radiative flux, respectively, as the components' residual. Best estimates of multi-year (2005–2020) EEI are derived from temporal changes in planetary heat content, predominantly ocean heat content, and amount to ~0.9 Wm−2. To monitor EEI directly from space, we propose an independent approach based on accelerometry that measures non-gravitational radial accelerations induced by radiation pressure. To provide requirements for a near-spherical “Space Balls” spacecraft and mission design, we develop a simulation environment using JPL's Mission Analysis, Operations, and Navigation Toolkit Environment (MONTE) software libraries and present-day radiative fluxes from the Clouds and Earth's Radiant Energy System (CERES). At its current initial stage, the toolset allows us to simulate accelerations acting on a spherical spacecraft due to solar radiation pressure, Earth's reflected shortwave (albedo) and emitted longwave radiation, as well as due to aerodynamic force. Induced accelerations as well as their sensitivity to mean orbit altitude and spacecraft absorptivity agree well with back-of the-envelope calculations and previous simulations that assess the role of radiation pressure accelerations for orbital drift. Future investigations will expand the MONTE-based simulation environment with additional shape and confounding force models. Preliminary simulations with an integrated spacecraft dynamics model suggest that the main confounding accelerations for a non-perfect, faceted sphere are related to Yarkovsky, aerodynamic force and relativistic effects, which will have to be mitigated to facilitate a high-accuracy EEI measurement from space.","PeriodicalId":344285,"journal":{"name":"2023 IEEE Aerospace Conference","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128083362","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 : 2023-03-04DOI: 10.1109/AERO55745.2023.10115720
Alexandre T. Guibert, Robert J. Chambers, Pengcheng Cao, H. Kim, S. Cai, F. Kuester
This paper introduces the design, modeling, manufacturing, and testing of a Gripping Aerial Topology Optimized Robot (GATOR). The airframe of this unmanned aerial vehicle (UAV) is designed to be lightweight, structurally stiff, modular, and multi-functional. A Level-Set Topology Optimization (LSTO) method defines the external geometry of the frame, while the frame infill is controlled using a variable thickness latticing technique based on Finite Element Analysis (FEA) results. The UAV incorporates a soft robotic gripper, allowing the vehicle to collect delicate samples from the environment and perch for low-power use for extended periods. The bio-inspired design and fabrication of a mountable soft robotic gripper are presented and the associated kinematics are derived for controls. To further decrease the weight of the designs a novel volume-changing material was introduced following careful characterization through Scanning Electron Microscopy (SEM) and tensile testing. The resulting platform leverages additive manufacturing using material extrusion technology and can be swiftly instrumented with propulsion and flight control systems. The presented modular design methodology can be applied to the rapid prototyping of a broad range of aerial platforms and lightweight structures.
{"title":"Gripping Aerial Topology Optimized Robot (GATOR)","authors":"Alexandre T. Guibert, Robert J. Chambers, Pengcheng Cao, H. Kim, S. Cai, F. Kuester","doi":"10.1109/AERO55745.2023.10115720","DOIUrl":"https://doi.org/10.1109/AERO55745.2023.10115720","url":null,"abstract":"This paper introduces the design, modeling, manufacturing, and testing of a Gripping Aerial Topology Optimized Robot (GATOR). The airframe of this unmanned aerial vehicle (UAV) is designed to be lightweight, structurally stiff, modular, and multi-functional. A Level-Set Topology Optimization (LSTO) method defines the external geometry of the frame, while the frame infill is controlled using a variable thickness latticing technique based on Finite Element Analysis (FEA) results. The UAV incorporates a soft robotic gripper, allowing the vehicle to collect delicate samples from the environment and perch for low-power use for extended periods. The bio-inspired design and fabrication of a mountable soft robotic gripper are presented and the associated kinematics are derived for controls. To further decrease the weight of the designs a novel volume-changing material was introduced following careful characterization through Scanning Electron Microscopy (SEM) and tensile testing. The resulting platform leverages additive manufacturing using material extrusion technology and can be swiftly instrumented with propulsion and flight control systems. The presented modular design methodology can be applied to the rapid prototyping of a broad range of aerial platforms and lightweight structures.","PeriodicalId":344285,"journal":{"name":"2023 IEEE Aerospace Conference","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133724183","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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