Unlike the Earth environment, the Martian atmosphere is mainly composed of carbon dioxide, which is characterized by low temperature and low density, resulting significant effects on the aerodynamic characteristics of air vehicles than those observed at the earth's atmosphere. In this study the effects of working fluids and the geometric designs of airfoils on the aerodynamic performance of 3D wing operating under Martian atmospheric conditions is performed, employing the experimental and numerical approaches. In addition, considering the operating environment of MARS, the effects of Reynolds and Mach numbers have also been studied at a larger scale. The results show that the working fluid does not significantly affect the aerodynamic performance of the wing, which is observed greatly sensitive to the variations in the flow Reynolds numbers, having lesser dependency on the Mach number. And the geometric design of airfoils is observed to greatly influence the wing aerodynamics operating at Martian conditions. Additionally, the numerical results present detailed insights on the stall onset for each operating conditions accompanied by the transformation of small-size high-frequency vortex shedding to large-size low-frequency vortex shedding.
{"title":"Studies on the effect of working fluid and the geometric design of airfoils on the aerodynamic performance of air vehicles operating in Martian atmosphere","authors":"Junli Wang, Zhi Deng, Yuhang Zhang, Chen Liu, Wenli Chen, Jian Wu","doi":"10.1016/j.actaastro.2025.01.039","DOIUrl":"https://doi.org/10.1016/j.actaastro.2025.01.039","url":null,"abstract":"Unlike the Earth environment, the Martian atmosphere is mainly composed of carbon dioxide, which is characterized by low temperature and low density, resulting significant effects on the aerodynamic characteristics of air vehicles than those observed at the earth's atmosphere. In this study the effects of working fluids and the geometric designs of airfoils on the aerodynamic performance of 3D wing operating under Martian atmospheric conditions is performed, employing the experimental and numerical approaches. In addition, considering the operating environment of MARS, the effects of Reynolds and Mach numbers have also been studied at a larger scale. The results show that the working fluid does not significantly affect the aerodynamic performance of the wing, which is observed greatly sensitive to the variations in the flow Reynolds numbers, having lesser dependency on the Mach number. And the geometric design of airfoils is observed to greatly influence the wing aerodynamics operating at Martian conditions. Additionally, the numerical results present detailed insights on the stall onset for each operating conditions accompanied by the transformation of small-size high-frequency vortex shedding to large-size low-frequency vortex shedding.","PeriodicalId":44971,"journal":{"name":"Acta Astronautica","volume":"79 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142990244","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-16DOI: 10.1016/j.actaastro.2024.12.051
Binfeng Pan, Yunting Ran, Mengxin Zhao
This paper introduces an innovative generalized Gaussian smoothing homotopy method for solving nonlinear optimal control problems using the indirect method. Compared to the original smoothing homotopy methods, this approach leverages a multivariate Gaussian function to smooth both state and costate variables, extending the convolution process beyond the time domain to all unknown variables. By utilizing the separability property of the Gaussian kernel, the multivariate convolution is decomposed into univariate convolutions along each dimension, allowing independent and efficient computation. Additionally, the Gauss–Chebyshev quadrature technique is employed to approximate these univariate convolutions, further reducing computational complexity. The convergence of the method is demonstrated through challenging numerical examples, showcasing its superiority over Gaussian smoothing homotopy method.
{"title":"Generalized Gaussian smoothing homotopy method for solving nonlinear optimal control problems","authors":"Binfeng Pan, Yunting Ran, Mengxin Zhao","doi":"10.1016/j.actaastro.2024.12.051","DOIUrl":"https://doi.org/10.1016/j.actaastro.2024.12.051","url":null,"abstract":"This paper introduces an innovative generalized Gaussian smoothing homotopy method for solving nonlinear optimal control problems using the indirect method. Compared to the original smoothing homotopy methods, this approach leverages a multivariate Gaussian function to smooth both state and costate variables, extending the convolution process beyond the time domain to all unknown variables. By utilizing the separability property of the Gaussian kernel, the multivariate convolution is decomposed into univariate convolutions along each dimension, allowing independent and efficient computation. Additionally, the Gauss–Chebyshev quadrature technique is employed to approximate these univariate convolutions, further reducing computational complexity. The convergence of the method is demonstrated through challenging numerical examples, showcasing its superiority over Gaussian smoothing homotopy method.","PeriodicalId":44971,"journal":{"name":"Acta Astronautica","volume":"9 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142990245","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-14DOI: 10.1016/j.actaastro.2025.01.011
Michael Matessa
Previous work has developed algorithms for decoding the meaning of an interstellar message from a distant civilization (Matessa, 2022). What about the inverse problem: if you have a concept like the mass of an object that you want to discuss, how can you create a message with that concept that can be easily decoded? This paper describes algorithms for creating a sequence of symbols that introduce concepts leading from basic mathematics to a target concept. The algorithms work with a data structure containing an expression form that relates concepts, a precondition of concepts that have been introduced previously in the message, and a postcondition of concepts that should be understood after the expression form is presented. These algorithms have been implemented in software, and results are shown for creating a message given a target concept. Messages that are created by the algorithms in this paper can be decoded by the algorithms in Matessa (2022). By developing algorithms, it is hoped that message encoding and decoding can grow from an art done by individuals to a science done with algorithms.
{"title":"Algorithms for encoding interstellar messages","authors":"Michael Matessa","doi":"10.1016/j.actaastro.2025.01.011","DOIUrl":"https://doi.org/10.1016/j.actaastro.2025.01.011","url":null,"abstract":"Previous work has developed algorithms for decoding the meaning of an interstellar message from a distant civilization (Matessa, 2022). What about the inverse problem: if you have a concept like the mass of an object that you want to discuss, how can you create a message with that concept that can be easily decoded? This paper describes algorithms for creating a sequence of symbols that introduce concepts leading from basic mathematics to a target concept. The algorithms work with a data structure containing an expression form that relates concepts, a precondition of concepts that have been introduced previously in the message, and a postcondition of concepts that should be understood after the expression form is presented. These algorithms have been implemented in software, and results are shown for creating a message given a target concept. Messages that are created by the algorithms in this paper can be decoded by the algorithms in Matessa (2022). By developing algorithms, it is hoped that message encoding and decoding can grow from an art done by individuals to a science done with algorithms.","PeriodicalId":44971,"journal":{"name":"Acta Astronautica","volume":"12 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142989647","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-14DOI: 10.1016/j.actaastro.2025.01.013
Diego Navarro-Tapia, Andrés Marcos, Marc Hirth
This article studies and provides a plausible solution to address the effects of micro-particle impacts on the LISA mission. The influence of these undesired events are analysed using a set of 8 worst-case impact conditions from an ESA database of more than 200,000 impacts that captures the anticipated micro-meteoroid environment that the LISA spacecraft may encounter in a span of its envisioned 6.5 years of mission. Based on the results of this analysis, a novel operational mode called SCIHOLD is proposed to provide fast recovery from micro-meteoroid impacts. The performance of the SCIHOLD mode is validated using a LISA high-fidelity, non-linear simulator in two steps. Firstly, the identified 8 worst-case impacts are evaluated in nominal and dispersed conditions in a Monte Carlo campaign, and secondly, larger impacts beyond the ones in the database are simulated to assess the recovery limits of the proposed recovery mode. The results show that the proposed operational mode is successful in recovering the LISA spacecraft from the impacts, and most importantly, that this is achieved with a mean overall recovery time of 92.5s, a considerable reduction compared to a full re-acquisition scenario typically lasting hours.
{"title":"Fast recovery mode for micro-meteoroid impacts: A LISA mission study","authors":"Diego Navarro-Tapia, Andrés Marcos, Marc Hirth","doi":"10.1016/j.actaastro.2025.01.013","DOIUrl":"https://doi.org/10.1016/j.actaastro.2025.01.013","url":null,"abstract":"This article studies and provides a plausible solution to address the effects of micro-particle impacts on the LISA mission. The influence of these undesired events are analysed using a set of 8 worst-case impact conditions from an ESA database of more than 200,000 impacts that captures the anticipated micro-meteoroid environment that the LISA spacecraft may encounter in a span of its envisioned 6.5 years of mission. Based on the results of this analysis, a novel operational mode called SCIHOLD is proposed to provide fast recovery from micro-meteoroid impacts. The performance of the SCIHOLD mode is validated using a LISA high-fidelity, non-linear simulator in two steps. Firstly, the identified 8 worst-case impacts are evaluated in nominal and dispersed conditions in a Monte Carlo campaign, and secondly, larger impacts beyond the ones in the database are simulated to assess the recovery limits of the proposed recovery mode. The results show that the proposed operational mode is successful in recovering the LISA spacecraft from the impacts, and most importantly, that this is achieved with a mean overall recovery time of 92.5<ce:hsp sp=\"0.16667\"></ce:hsp>s, a considerable reduction compared to a full re-acquisition scenario typically lasting hours.","PeriodicalId":44971,"journal":{"name":"Acta Astronautica","volume":"37 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142989641","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The design of satellite attitude-control thrusters depends on a trade-off between minimum impulse bit and specific impulse, where the width of pulse maneuvers relies on the combination of delays in the hydraulic system (feed tubes and valves) and the ignition delay time of the propellant used. The most well-established propellants in this context are hydrazine derivatives and nitrogen tetroxide. However, their high toxicity makes satellite integration costly and environmentally hazardous. To replace these propellants, research is focused on developing new hypergolic green propellants, most of which use high-concentration hydrogen peroxide as an oxidizer. In this study, the hypergolic reaction between a blend of n-butanol and monoethanolamine and hydrogen peroxide was catalyzed using copper nitrate trihydrate. The central composite design method was applied to optimize fuel composition using 90% hydrogen peroxide as the oxidizer. The optimization yielded two key outcomes: for ignition delay time (31.5% n-butanol, 60% monoethanolamine, and 8.5% copper nitrate, resulting in an ignition delay time of 21.5 ms with a standard deviation of ±1.30 ms and a systematic error of ±0.4), and for theoretical specific impulse (36% n-butanol, 60% monoethanolamine, and 4% copper nitrate, with an ignition delay time of 26 ±0.4 ms). For the ignition delay time optimization, an oxidizer-fuel ratio of 4 was selected using CEA NASA software to achieve a maximum theoretical specific impulse of 170.64 s, while for specific impulse optimization, a ratio of 4.4 was chosen, resulting in a specific impulse of 171.58 s. Although the maximum theoretical specific impulse of the proposed green propellant pair does not present an advantage if compared to traditional hypergolic propellants, it offers a competitive advantage in terms of density-specific impulse, with the highest value achieved in the ignition delay time optimization, where the density-specific impulse of the system reached 267.5 gs/cm3. Furthermore, the addition of n-butanol effectively reduced fuel viscosity, enhanced density-specific impulse, increased specific impulse, and improved ignition delay time response with 90% hydrogen peroxide compared to pure monoethanolamine formulations for a specific chamber and nozzle configuration. These findings highlight the potential of this green propellant system to enhance performance and efficiency in aerospace applications.
卫星姿态控制推进器的设计取决于最小脉冲位和比脉冲之间的权衡，其中脉冲机动的宽度取决于液压系统（进料管和阀门）的延迟和所用推进剂的点火延迟时间的组合。在这方面，最成熟的推进剂是肼衍生物和四氧化二氮。然而，它们的高毒性使卫星集成成本高昂，而且对环境有害。为了取代这些推进剂，研究的重点是开发新的自燃绿色推进剂，这些推进剂大多使用高浓度过氧化氢作为氧化剂。在本研究中，用三水合硝酸铜催化正丁醇和单乙醇胺的混合物与过氧化氢的自燃反应。以90%过氧化氢为氧化剂，采用中心复合设计方法对燃料组成进行优化。优化得到两个关键结果：点火延迟时间（31.5%正丁醇、60%单乙醇胺和8.5%硝酸铜）为21.5 ms，标准偏差为±1.30 ms，系统误差为±0.4)；理论比冲（36%正丁醇、60%单乙醇胺和4%硝酸铜）为26±0.4 ms。在点火延迟时间优化方面，采用CEA NASA软件选择氧化燃料比为4，理论比冲最大为170.64 s，比冲优化选择比为4.4，理论比冲最大为171.58 s。虽然与传统自燃推进剂相比，所提出的绿色推进剂对的最大理论比冲并不具有优势，但它在密度比冲方面具有竞争优势，在点火延迟时间优化中达到了最大值，其中系统的密度比冲达到267.5 g /cm3。此外，在特定的燃烧室和喷嘴配置下，与纯乙醇胺配方相比，添加正丁醇有效地降低了燃料粘度，增强了密度比冲，增加了比冲，并改善了90%过氧化氢时的点火延迟时间响应。这些发现突出了这种绿色推进剂系统在提高航空航天应用性能和效率方面的潜力。
{"title":"Composition optimization of a hypergolic green propellant based on monoethanolamine, n-butanol and 90% hydrogen peroxide","authors":"Paull C. Acosta Mendoza, Rene F.B. Gonçalves, Leonardo Henrique Gouvêa, Luís Gustavo Ferroni Pereira","doi":"10.1016/j.actaastro.2024.12.059","DOIUrl":"https://doi.org/10.1016/j.actaastro.2024.12.059","url":null,"abstract":"The design of satellite attitude-control thrusters depends on a trade-off between minimum impulse bit and specific impulse, where the width of pulse maneuvers relies on the combination of delays in the hydraulic system (feed tubes and valves) and the ignition delay time of the propellant used. The most well-established propellants in this context are hydrazine derivatives and nitrogen tetroxide. However, their high toxicity makes satellite integration costly and environmentally hazardous. To replace these propellants, research is focused on developing new hypergolic green propellants, most of which use high-concentration hydrogen peroxide as an oxidizer. In this study, the hypergolic reaction between a blend of n-butanol and monoethanolamine and hydrogen peroxide was catalyzed using copper nitrate trihydrate. The central composite design method was applied to optimize fuel composition using 90% hydrogen peroxide as the oxidizer. The optimization yielded two key outcomes: for ignition delay time (31.5% n-butanol, 60% monoethanolamine, and 8.5% copper nitrate, resulting in an ignition delay time of 21.5 ms with a standard deviation of ±1.30 ms and a systematic error of ±0.4), and for theoretical specific impulse (36% n-butanol, 60% monoethanolamine, and 4% copper nitrate, with an ignition delay time of 26 ±0.4 ms). For the ignition delay time optimization, an oxidizer-fuel ratio of 4 was selected using CEA NASA software to achieve a maximum theoretical specific impulse of 170.64 s, while for specific impulse optimization, a ratio of 4.4 was chosen, resulting in a specific impulse of 171.58 s. Although the maximum theoretical specific impulse of the proposed green propellant pair does not present an advantage if compared to traditional hypergolic propellants, it offers a competitive advantage in terms of density-specific impulse, with the highest value achieved in the ignition delay time optimization, where the density-specific impulse of the system reached 267.5 gs/cm<mml:math altimg=\"si131.svg\" display=\"inline\"><mml:msup><mml:mrow></mml:mrow><mml:mrow><mml:mn>3</mml:mn></mml:mrow></mml:msup></mml:math>. Furthermore, the addition of n-butanol effectively reduced fuel viscosity, enhanced density-specific impulse, increased specific impulse, and improved ignition delay time response with 90% hydrogen peroxide compared to pure monoethanolamine formulations for a specific chamber and nozzle configuration. These findings highlight the potential of this green propellant system to enhance performance and efficiency in aerospace applications.","PeriodicalId":44971,"journal":{"name":"Acta Astronautica","volume":"9 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142989648","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-10DOI: 10.1016/j.actaastro.2025.01.027
Lixiang Li, Christian Ingabire, Daolun Liang, Ji Li, Yunan Zhou, Yue Jiang, Dekui Shen
Compared to casting process, the advantages of additive manufacturing (AM) technology, such as the elimination of mold requirements, and enhanced adaptability to complex geometries, render it highly promising for applications involving the configuration of energy release gradients, and regulation of combustion processes. To explore the disparities in mechanical performance and combustion characteristics of printed and casted propellants, a computed tomographic scanner and a universal testing machine were employed to characterize the pore structure and tensile strength. A visual online detection experimental system was established to investigate the combustion characteristics under 1–9 atm, with the condensed combustion products (CCPs) being diagnosed. Results indicate that the printed sample exhibits a lower porosity, a higher density, and a greater tensile strength. Under identical pressure, the radial flame diffusion of printed strand is weaker, whereas the axial diffusion is stronger. The burning rates and combustion temperatures of the printed strand consistently exceed those of the casted strands, with this disparity progressively widening during pressure increasing. Moreover, the printed strand exhibits enhanced combustion stability. The diagnostic results indicate that the CCPs can be categorized into smoke oxide particles (SOPs), spherical agglomerates (SAGs) and irregular agglomerates (IAGs), and the particle size of the printed strand is smaller than that of the casted strand under high pressures. The printed strand exhibits characteristic of complete combustion at lower pressures, as evidenced by the obvious high XRD peak of Al2O3 and the higher combustion efficiency. The AM process reduces the porosity of propellant, thereby intensifying the consumption rate of reactants, and increasing the combustion intensity. This study contributes to a deeper understanding of the application of AM on the solid propellants.
{"title":"Comparative study on mechanical properties and combustion characteristics of additive manufacturing/casting composite solid propellants","authors":"Lixiang Li, Christian Ingabire, Daolun Liang, Ji Li, Yunan Zhou, Yue Jiang, Dekui Shen","doi":"10.1016/j.actaastro.2025.01.027","DOIUrl":"https://doi.org/10.1016/j.actaastro.2025.01.027","url":null,"abstract":"Compared to casting process, the advantages of additive manufacturing (AM) technology, such as the elimination of mold requirements, and enhanced adaptability to complex geometries, render it highly promising for applications involving the configuration of energy release gradients, and regulation of combustion processes. To explore the disparities in mechanical performance and combustion characteristics of printed and casted propellants, a computed tomographic scanner and a universal testing machine were employed to characterize the pore structure and tensile strength. A visual online detection experimental system was established to investigate the combustion characteristics under 1–9 atm, with the condensed combustion products (CCPs) being diagnosed. Results indicate that the printed sample exhibits a lower porosity, a higher density, and a greater tensile strength. Under identical pressure, the radial flame diffusion of printed strand is weaker, whereas the axial diffusion is stronger. The burning rates and combustion temperatures of the printed strand consistently exceed those of the casted strands, with this disparity progressively widening during pressure increasing. Moreover, the printed strand exhibits enhanced combustion stability. The diagnostic results indicate that the CCPs can be categorized into smoke oxide particles (SOPs), spherical agglomerates (SAGs) and irregular agglomerates (IAGs), and the particle size of the printed strand is smaller than that of the casted strand under high pressures. The printed strand exhibits characteristic of complete combustion at lower pressures, as evidenced by the obvious high XRD peak of Al<ce:inf loc=\"post\">2</ce:inf>O<ce:inf loc=\"post\">3</ce:inf> and the higher combustion efficiency. The AM process reduces the porosity of propellant, thereby intensifying the consumption rate of reactants, and increasing the combustion intensity. This study contributes to a deeper understanding of the application of AM on the solid propellants.","PeriodicalId":44971,"journal":{"name":"Acta Astronautica","volume":"76 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142967833","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-09DOI: 10.1016/j.actaastro.2025.01.026
Juan Miguel Sánchez-Lozano, Eloy Peña-Asensio, Valentin T. Bickel, David A. Kring
Properly designed astronaut traverses are decisive for the science return and safety of crewed lunar missions to the Moon. Their development and planning are challenged by numerous parameters involved and the difficulty of determining their relative importance. Investigating the potential of Multi-Criteria Decision-Making (MCDM) techniques for lunar exploration within the context of Artemis III, this paper demonstrates the effective application of the well-established Analytic Hierarchy Process (AHP) and the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS). AHP is utilized to derive weights for evaluating criteria, informed by inputs from scientists and engineers, emphasizing the geological interest and temperature of Permanently Shadowed Regions (PSR), followed by the slope profile of the traverse, although weighting is conditioned by expert background. TOPSIS is then applied to objectively rank astronaut traverses to PSRs at sites 001 and 004, situated on the ‘Connecting Ridge’ region. This analysis not only identifies a particular traverse from site 001 that is significantly superior to others but also conducts a sensitivity analysis to assess the impact of challenging-to-quantify criteria such as geological interest. These findings underscore the considerable potential of MCDM techniques to enhance decision-making in lunar missions, thereby promising to improve the efficacy, science return, and safety of future Artemis missions through a systematic approach to complex trade-off decision landscapes.
{"title":"Prioritizing astronaut traverses on the Moon: A multi-criteria decision-making approach","authors":"Juan Miguel Sánchez-Lozano, Eloy Peña-Asensio, Valentin T. Bickel, David A. Kring","doi":"10.1016/j.actaastro.2025.01.026","DOIUrl":"https://doi.org/10.1016/j.actaastro.2025.01.026","url":null,"abstract":"Properly designed astronaut traverses are decisive for the science return and safety of crewed lunar missions to the Moon. Their development and planning are challenged by numerous parameters involved and the difficulty of determining their relative importance. Investigating the potential of Multi-Criteria Decision-Making (MCDM) techniques for lunar exploration within the context of Artemis III, this paper demonstrates the effective application of the well-established Analytic Hierarchy Process (AHP) and the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS). AHP is utilized to derive weights for evaluating criteria, informed by inputs from scientists and engineers, emphasizing the geological interest and temperature of Permanently Shadowed Regions (PSR), followed by the slope profile of the traverse, although weighting is conditioned by expert background. TOPSIS is then applied to objectively rank astronaut traverses to PSRs at sites 001 and 004, situated on the ‘Connecting Ridge’ region. This analysis not only identifies a particular traverse from site 001 that is significantly superior to others but also conducts a sensitivity analysis to assess the impact of challenging-to-quantify criteria such as geological interest. These findings underscore the considerable potential of MCDM techniques to enhance decision-making in lunar missions, thereby promising to improve the efficacy, science return, and safety of future Artemis missions through a systematic approach to complex trade-off decision landscapes.","PeriodicalId":44971,"journal":{"name":"Acta Astronautica","volume":"41 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142975196","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper proposes a method of capturing small celestial bodies (SCB) by multi-tethered spacecraft formation (MTSF), and the system design and experimental verification are carried out. This method can be used in SCB exploration deep sampling to provide penetration force between the drilling equipment and the star soil. Firstly, the composition and operation flow of the encirclement capture system is described, and the encirclement load unit is designed. The dual quaternion describes the rigid body position and attitude coupling motion, and the Arbitrary Lagrange–Euler and the Absolute Nodal Coordinate Formulation (ALE-ANCF) method describes the variable length tether motion. The dynamic model of the variable length MTSF system is established. Finally, a hybrid formation test platform of air-floating node (AFN) and unmanned air vehicle (UAV) is constructed to simulate the capture process of a three-node spacecraft on the scaled model of a SCB. The results show that the AFN and the UAV cooperatively carry the tether retracting and releasing device to form the encirclement configuration and converge to the desired position and attitude. Finally, the tether configuration realizes the slinging of the SCB scale model, which verifies the feasibility of the encirclement method.
{"title":"Design and experimental verification of multi-tethered spacecraft formation encircled to capture small celestial body system","authors":"Yu Yang, Yixin Huang, Hao Tian, Yuchen Zhu, Changzheng Qian, Yang Zhao","doi":"10.1016/j.actaastro.2025.01.015","DOIUrl":"https://doi.org/10.1016/j.actaastro.2025.01.015","url":null,"abstract":"This paper proposes a method of capturing small celestial bodies (SCB) by multi-tethered spacecraft formation (MTSF), and the system design and experimental verification are carried out. This method can be used in SCB exploration deep sampling to provide penetration force between the drilling equipment and the star soil. Firstly, the composition and operation flow of the encirclement capture system is described, and the encirclement load unit is designed. The dual quaternion describes the rigid body position and attitude coupling motion, and the Arbitrary Lagrange–Euler and the Absolute Nodal Coordinate Formulation (ALE-ANCF) method describes the variable length tether motion. The dynamic model of the variable length MTSF system is established. Finally, a hybrid formation test platform of air-floating node (AFN) and unmanned air vehicle (UAV) is constructed to simulate the capture process of a three-node spacecraft on the scaled model of a SCB. The results show that the AFN and the UAV cooperatively carry the tether retracting and releasing device to form the encirclement configuration and converge to the desired position and attitude. Finally, the tether configuration realizes the slinging of the SCB scale model, which verifies the feasibility of the encirclement method.","PeriodicalId":44971,"journal":{"name":"Acta Astronautica","volume":"60 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142975149","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-07DOI: 10.1016/j.actaastro.2025.01.004
Shao Nie, Fei Qin, Jinying Ye, Xianggeng Wei, Guoqiang He
One of the principal research subjects within the field of rocket-based combined cycle (RBCC) engines has been the ejector mode, which has been the focus of research for a considerable period of time. The objective of this paper is to present a detailed analysis to the ejector mode of kerosene-fueled RBCC engine. The matching mechanism of the diffusion and afterburning (DAB) mode was obtained through a combination of experiment, theoretical modeling, and numerical simulation. The thrust gain of the sea-level ejector mode was subsequently analyzed. The findings indicate that: (1) In the DAB mode, the requirement of the thermal or geometric throat area ratio is small. The difficulty in organizing the thermal throat has led to the use of a geometric throat to achieve choking on the engine. The results of the model calculation indicate that a thrust gain of 25.2 % for a sea-level ejector mode can be achieved by employing a throat area ratio of 1.83. (2) For the sea-level ejector mode, the mixing requirement can be satisfied when the length of the mixing section reaches 4 times the hydraulic diameter of the rocket nozzle outlet's section. The use of a throat area ratio of 1.8 allows for a thrust gain of 15.9 % in the sea-level ejector mode. The presence of fuel pylons has been observed to reduce thrust gain. (3) The matching mechanism of sea-level ejector mode is revealed. When the rocket flow rate, bypass ratio, combustion organization and throat area ratio match, the maximum thrust gain can be achieved.
{"title":"Investigation on sea-level thrust gain in ejector mode of rocket-based combined cycle engine","authors":"Shao Nie, Fei Qin, Jinying Ye, Xianggeng Wei, Guoqiang He","doi":"10.1016/j.actaastro.2025.01.004","DOIUrl":"https://doi.org/10.1016/j.actaastro.2025.01.004","url":null,"abstract":"One of the principal research subjects within the field of rocket-based combined cycle (RBCC) engines has been the ejector mode, which has been the focus of research for a considerable period of time. The objective of this paper is to present a detailed analysis to the ejector mode of kerosene-fueled RBCC engine. The matching mechanism of the diffusion and afterburning (DAB) mode was obtained through a combination of experiment, theoretical modeling, and numerical simulation. The thrust gain of the sea-level ejector mode was subsequently analyzed. The findings indicate that: (1) In the DAB mode, the requirement of the thermal or geometric throat area ratio is small. The difficulty in organizing the thermal throat has led to the use of a geometric throat to achieve choking on the engine. The results of the model calculation indicate that a thrust gain of 25.2 % for a sea-level ejector mode can be achieved by employing a throat area ratio of 1.83. (2) For the sea-level ejector mode, the mixing requirement can be satisfied when the length of the mixing section reaches 4 times the hydraulic diameter of the rocket nozzle outlet's section. The use of a throat area ratio of 1.8 allows for a thrust gain of 15.9 % in the sea-level ejector mode. The presence of fuel pylons has been observed to reduce thrust gain. (3) The matching mechanism of sea-level ejector mode is revealed. When the rocket flow rate, bypass ratio, combustion organization and throat area ratio match, the maximum thrust gain can be achieved.","PeriodicalId":44971,"journal":{"name":"Acta Astronautica","volume":"9 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142967737","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-07DOI: 10.1016/j.actaastro.2025.01.002
Peineng Zhong, Lusi Wang, Guangfei Zhang, Xiayu Li, Jinchang Xu, Qichen Sun, Suping Wang, Suolai Zhang, Chu Wang, Lei Chen, Xu Yang, Kun Xu, Xilun Ding, Tao Zhang
Water ice, extensively detected in the lunar south polar region, represents a valuable resource for future lunar base construction and energy utilization. To gain a comprehensive understanding of the origin, distribution, and properties of water ice in the lunar polar regions, on-site measurement is essential. In alignment with this goal, China’s Chang’E 7 mission, scheduled for launch in 2026, aims to explore water ice within permanently shadowed regions of the lunar south pole through drilling and in-situ measurement of water content. This work presents the design and development of a thermal-vacuum regolith environment simulator, specifically created to test the performance of a robotic drill under conditions simulating the icy lunar regolith of the lunar polar environment. The simulator comprises a vacuum acquisition system, a cryogenic cooling system, and a preparation system for icy lunar regolith simulant. Additionally, the simulator can effectively adjust the position of the lunar regolith container and visually monitor it. The vacuum acquisition system provides a low-pressure environment suitable for drilling tests with icy lunar regolith simulant, while the cryogenic cooling system refrigerates the simulant to a temperature as low as 95 K (−178 °C). The regolith preparation system, moreover, enables controlled mixing and compaction of regolith simulant to specific bulk densities and water contents. To enhance testing efficiency in simulated thermal-vacuum environments, the simulator includes a rotation mechanism that allows multiple drilling tests within a single environmental setup by adjusting the position of the regolith container. Experimental validation confirms the capacity of the simulator to replicate conditions similar to those in lunar polar regions. Specifically, the vacuum acquisition system can pump the chamber to a pressure in the order of 10−1 Pa when loaded with icy lunar regolith simulant, and the cryogenic cooling system can refrigerate the regolith simulant with water contents of 0.5 wt% and 4 wt% to 95 K. This work can provide essential ground-testing support and technical validation for the upcoming drilling and sampling tasks of the Chinese Chang’E 7 mission.
{"title":"Thermal-vacuum regolith environment simulator for drilling tests in lunar polar regions","authors":"Peineng Zhong, Lusi Wang, Guangfei Zhang, Xiayu Li, Jinchang Xu, Qichen Sun, Suping Wang, Suolai Zhang, Chu Wang, Lei Chen, Xu Yang, Kun Xu, Xilun Ding, Tao Zhang","doi":"10.1016/j.actaastro.2025.01.002","DOIUrl":"https://doi.org/10.1016/j.actaastro.2025.01.002","url":null,"abstract":"Water ice, extensively detected in the lunar south polar region, represents a valuable resource for future lunar base construction and energy utilization. To gain a comprehensive understanding of the origin, distribution, and properties of water ice in the lunar polar regions, on-site measurement is essential. In alignment with this goal, China’s Chang’E 7 mission, scheduled for launch in 2026, aims to explore water ice within permanently shadowed regions of the lunar south pole through drilling and <ce:italic>in-situ</ce:italic> measurement of water content. This work presents the design and development of a thermal-vacuum regolith environment simulator, specifically created to test the performance of a robotic drill under conditions simulating the icy lunar regolith of the lunar polar environment. The simulator comprises a vacuum acquisition system, a cryogenic cooling system, and a preparation system for icy lunar regolith simulant. Additionally, the simulator can effectively adjust the position of the lunar regolith container and visually monitor it. The vacuum acquisition system provides a low-pressure environment suitable for drilling tests with icy lunar regolith simulant, while the cryogenic cooling system refrigerates the simulant to a temperature as low as 95 K (<mml:math altimg=\"si22.svg\" display=\"inline\"><mml:mrow><mml:mo>−</mml:mo><mml:mn>178</mml:mn></mml:mrow></mml:math> °C). The regolith preparation system, moreover, enables controlled mixing and compaction of regolith simulant to specific bulk densities and water contents. To enhance testing efficiency in simulated thermal-vacuum environments, the simulator includes a rotation mechanism that allows multiple drilling tests within a single environmental setup by adjusting the position of the regolith container. Experimental validation confirms the capacity of the simulator to replicate conditions similar to those in lunar polar regions. Specifically, the vacuum acquisition system can pump the chamber to a pressure in the order of <mml:math altimg=\"si2.svg\" display=\"inline\"><mml:mrow><mml:mn>1</mml:mn><mml:msup><mml:mrow><mml:mn>0</mml:mn></mml:mrow><mml:mrow><mml:mo>−</mml:mo><mml:mn>1</mml:mn></mml:mrow></mml:msup></mml:mrow></mml:math> Pa when loaded with icy lunar regolith simulant, and the cryogenic cooling system can refrigerate the regolith simulant with water contents of 0.5 wt% and 4 wt% to 95 K. This work can provide essential ground-testing support and technical validation for the upcoming drilling and sampling tasks of the Chinese Chang’E 7 mission.","PeriodicalId":44971,"journal":{"name":"Acta Astronautica","volume":"128 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142967736","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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