Journal of Spacecraft and Rockets最新文献_第3页

Single-Agent Reinforcement Learning for Scalable Earth-Observing Satellite Constellation Operations 可扩展地球观测卫星星座操作的单智能体强化学习

4区工程技术

Journal of Spacecraft and Rockets Pub Date : 2023-11-02 DOI: 10.2514/1.a35736

Adam Herrmann, Mark A. Stephenson, Hanspeter Schaub

{"title":"Single-Agent Reinforcement Learning for Scalable Earth-Observing Satellite Constellation Operations","authors":"Adam Herrmann, Mark A. Stephenson, Hanspeter Schaub","doi":"10.2514/1.a35736","DOIUrl":"https://doi.org/10.2514/1.a35736","url":null,"abstract":"This work explores single-agent reinforcement learning for the multi-satellite agile Earth-observing scheduling problem. The objective of the problem is to maximize the weighted sum of imaging targets collected and downlinked while avoiding resource constraint violations on board the spacecraft. To avoid the computational complexity associated with multi-agent deep reinforcement learning while creating a robust and scalable solution, a policy is trained in a single satellite environment. This policy is then deployed on board each satellite in a Walker-delta constellation. A global set of targets is distributed to each satellite based on target access. The satellites communicate with one another to determine whether an imaging target is imaged or downlinked. Free communication, line-of-sight communication, and no communication are explored to determine how the communication assumptions and constellation design impact performance. Free communication is shown to produce the best performance, and no communication is shown to produce the worst performance. Line-of-sight communication performance is shown to depend heavily on the design of the constellation and how frequently the satellites can communicate with one another. To explore how higher-level coordination can impact performance, a centralized mixed-integer programming optimization approach to global target distribution is explored and compared to a decentralized approach. A genetic algorithm is also implemented for comparison purposes, and the proposed method is shown to achieve higher reward on average at a fraction of the computational cost.","PeriodicalId":50048,"journal":{"name":"Journal of Spacecraft and Rockets","volume":"33 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135934234","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

First Approximation of Population Distributions on the International Space Station 国际空间站人口分布的第一次近似

4区工程技术

Journal of Spacecraft and Rockets Pub Date : 2023-10-26 DOI: 10.2514/1.a35686

Justin St. P. Walsh, Rao Hamza Ali, Alice C. Gorman, Amir Kanan Kashefi

{"title":"First Approximation of Population Distributions on the International Space Station","authors":"Justin St. P. Walsh, Rao Hamza Ali, Alice C. Gorman, Amir Kanan Kashefi","doi":"10.2514/1.a35686","DOIUrl":"https://doi.org/10.2514/1.a35686","url":null,"abstract":"This paper presents an analysis of data derived from thousands of publicly available photographs showing life on the International Space Station (ISS) between 2000 and 2020. Our analysis uses crew and locational information from the photographs’ metadata to identify the distribution of different population groups—by gender, nationality, and space agency affiliation—across modules of the ISS, for the first time. Given the significance of the ISS as the most intensively inhabited space habitat to date, an international cooperative initiative involving 26 countries and five space agencies, and one of the most expensive building projects ever undertaken by humans, developing an understanding of which people are using different parts of the space station is critical for future usage of this and other stations. This study also sheds light on problems faced by future space station designers who are concerned with optimal usage of their habitats. The data from this investigation have been permanently deposited with Open Context. It is freely available for use under a Creative Commons license (CC BY 4.0) at https://doi.org/10.6078/M7668B9H .","PeriodicalId":50048,"journal":{"name":"Journal of Spacecraft and Rockets","volume":"5 4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135013366","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Examining Distributed Fueling Schemes Using Tandem Cavities in a Mach 8 Scramjet 在马赫数8的超燃冲压发动机中使用串联式腔体研究分布式加氢方案

4区工程技术

Journal of Spacecraft and Rockets Pub Date : 2023-10-26 DOI: 10.2514/1.a35848

Sarah A. Mecklem, Damian Curran, Will O. Landsberg, Ananthanarayanan Veeraragavan

{"title":"Examining Distributed Fueling Schemes Using Tandem Cavities in a Mach 8 Scramjet","authors":"Sarah A. Mecklem, Damian Curran, Will O. Landsberg, Ananthanarayanan Veeraragavan","doi":"10.2514/1.a35848","DOIUrl":"https://doi.org/10.2514/1.a35848","url":null,"abstract":"A fundamental investigation of combustion behavior in an ethylene-fueled Mach 8 axisymmetric scramjet combustor was numerically conducted using US3D Reynolds-averaged Navier–Stokes to evaluate the impact of fueling strategies employed with a tandem cavity-equipped combustor. Five fueling configurations with a consistent total fuel-to-air equivalence ratio at 75% of stoichiometric were assessed using a combination of injector ports, located either upstream of, within, between, or downstream of the cavities. Cold-wall and hot-wall conditions were examined, representing shock tunnel equivalent test conditions with minimal wall heating and steady, in-flight wall temperatures, respectively. Two distributed fueling schemes resulted in higher combustion performance when operating in cold conditions and comparable performance when operating in hot conditions. Total pressure losses sustained under each distributed fueling method were equivalent to or lower than those sustained by cases with fuel injected only upstream of the cavities. All distributed schemes examined delayed the onset of flow separation, resulting in improved operational stability and higher resistance to engine unstart.","PeriodicalId":50048,"journal":{"name":"Journal of Spacecraft and Rockets","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135018368","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

CFD Modeling of Bidirectional PMDs Inside Cryogenic Propellant Tanks Onboard Parabolic Flights 抛物飞行中低温推进剂储罐内双向PMDs的CFD建模

4区工程技术

Journal of Spacecraft and Rockets Pub Date : 2023-10-25 DOI: 10.2514/1.a35808

Jason Hartwig, Narottama Esser, Shreykumar Jain, David Souders, Allen Prasad Varghese, Angelo Tafuni

{"title":"CFD Modeling of Bidirectional PMDs Inside Cryogenic Propellant Tanks Onboard Parabolic Flights","authors":"Jason Hartwig, Narottama Esser, Shreykumar Jain, David Souders, Allen Prasad Varghese, Angelo Tafuni","doi":"10.2514/1.a35808","DOIUrl":"https://doi.org/10.2514/1.a35808","url":null,"abstract":"Future cryogenic propulsion systems will require efficient methods for transferring cryogenic propellants from a depot storage tank to a customer receiver tank to minimize costs and maximize reusability. The Reduced Gravity Cryogenic Transfer Project is currently developing advanced cryogenic fluid management technology and developing and validating new numerical models for three phases of transfer: line chill down, tank chill down, and tank fill. Additionally, multiple liquid nitrogen ([Formula: see text]) parabolic flight transfer rigs are being designed by universities and NASA to investigate the gravitational sensitivities that exist in these three technologies. To maximize the collection of low-g data during flights, it is required to extract as much [Formula: see text] as possible from the supply tank, despite variable gravity levels. The purpose of this study is to present computational fluid dynamics volume of fluid simulations of [Formula: see text] behavior in the supply tank onboard parabolic flights to validate the optimal design of a bidirectional propellant management device (PMD) using the commercial software FLOW-3D. A parametric study was conducted on the effects of gravity level, fill level, pore size, open area, thickness, and type of baffle on PMD performance. Based on the results, the designed PMD exceeded the targeted expulsion efficiency.","PeriodicalId":50048,"journal":{"name":"Journal of Spacecraft and Rockets","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135167045","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Aerodynamic Effects of Surface Protuberance Size on Slender-Bodied Supersonic Vehicle 超声速细长体飞行器表面凸起尺寸对气动性能的影响

4区工程技术

Journal of Spacecraft and Rockets Pub Date : 2023-10-18 DOI: 10.2514/1.a35714

Kazuki Nimura, Fumiya Tsutsui, Keiichi Kitamura, Satoshi Nonaka

{"title":"Aerodynamic Effects of Surface Protuberance Size on Slender-Bodied Supersonic Vehicle","authors":"Kazuki Nimura, Fumiya Tsutsui, Keiichi Kitamura, Satoshi Nonaka","doi":"10.2514/1.a35714","DOIUrl":"https://doi.org/10.2514/1.a35714","url":null,"abstract":"The presence of protuberances can create an asymmetric flowfield, which contributes to side forces in slender-bodied launch vehicles. In this study, we conduct numerical calculations using a supercomputer at Japan Aerospace Exploration Agency (JAXA) on a slender body with a different-sized protuberance at Mach 1.5 to systematically determine the aerodynamic effects of the protuberance size. The protuberance size is varied in its height and width. According to the results, it is demonstrated that the side force significantly increases when the height of the protuberance increases. This is because, the higher the protuberance, the farther the wake vortex produced by the protuberance moved away from the body. Consequently, the flow asymmetry between the protuberance side and clean side is augmented, and the side force increases. In contrast, the side force is almost constant when only the width of the protuberance is changed. The results of this study indicate that when attaching the protuberance to the vehicles the height of the protuberance should be lowered, and the width of the protuberance should be increased to secure the volume of the protuberance and reduce the increase in side force.","PeriodicalId":50048,"journal":{"name":"Journal of Spacecraft and Rockets","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135887999","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Scheduling an Agile Multipayload Earth-Observing Satellite 敏捷多载荷地球观测卫星调度

4区工程技术

Journal of Spacecraft and Rockets Pub Date : 2023-10-18 DOI: 10.2514/1.a35726

Wenyuan Zhang, Gangtie Zheng

{"title":"Scheduling an Agile Multipayload Earth-Observing Satellite","authors":"Wenyuan Zhang, Gangtie Zheng","doi":"10.2514/1.a35726","DOIUrl":"https://doi.org/10.2514/1.a35726","url":null,"abstract":"A highly integrated Earth-observing satellite can possess several maneuverable payloads to perform different missions simultaneously, which brings some challenges to the method of task scheduling. This paper addresses the selection and scheduling problem of an agile satellite with several independently maneuverable optical payloads. Some differences compared to the traditional scheduling problem of agile satellites are presented and considered in a constrained optimization model. A two-stage method is proposed to accomplish the scheduling of the satellite and payloads in different stages. Clusters are generated from preprocessed tasks by a clique partition algorithm, and their centers are used to calculate the pointing direction of the satellite in the first stage. A multiobjective local search algorithm is introduced to schedule tasks in each selected cluster in the second stage. Considering the time-dependent property of the transition time, the problem of determining the start observation time is transformed into linear programming in a proposed insertion operator that guarantees the feasibility of generated solutions. Two types of instances are created and tested to demonstrate the effectiveness of the proposed method, and some analyses are conducted based on the experimental results.","PeriodicalId":50048,"journal":{"name":"Journal of Spacecraft and Rockets","volume":"129 36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135888067","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Risk Index for the Optimal Ranking of Active Debris Removal Targets 主动碎片清除目标最优排序的风险指数

4区工程技术

Journal of Spacecraft and Rockets Pub Date : 2023-10-11 DOI: 10.2514/1.a35752

Simone Servadio, Nihal Simha, Davide Gusmini, Daniel Jang, Theodore St. Francis, Andrea D’Ambrosio, Giovanni Lavezzi, Richard Linares

{"title":"Risk Index for the Optimal Ranking of Active Debris Removal Targets","authors":"Simone Servadio, Nihal Simha, Davide Gusmini, Daniel Jang, Theodore St. Francis, Andrea D’Ambrosio, Giovanni Lavezzi, Richard Linares","doi":"10.2514/1.a35752","DOIUrl":"https://doi.org/10.2514/1.a35752","url":null,"abstract":"The first step of any active debris removal (ADR) mission is the selection of the target. The optimal choice is to find the most dangerous debris that can be removed considering the chaser spacecraft requirements and mission constraints. After creating a catalog of the current space population in low Earth orbit (LEO), the MIT Monte Carlo Orbital Capacity Assessment Tool (MOCAT-MC) is used to simulate and predict the future space environment and the interaction among the space population. A novel performance index to quantify the criticality of each debris and the risk that it presents to the space environment is proposed. The new risk index considers the proximity of the debris to highly populated regions, its persistence in orbit, its likelihood to collide, and the estimated number and mass of debris that it can generate. The risk index is then optimized to work either with the full space population or a subset of it, where the ranking of risk among debris is highlighted. Multiple risk analyses are proposed in the test cases, where the ranked list of optimal targets is provided.","PeriodicalId":50048,"journal":{"name":"Journal of Spacecraft and Rockets","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136057481","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Space Launch System Unsteady Forces Developed from Unsteady-Pressure-Sensitive-Paint–Based Corcos Model Parameters 基于非定常压力敏感涂料模型参数的航天发射系统非定常力研究

4区工程技术

Journal of Spacecraft and Rockets Pub Date : 2023-10-06 DOI: 10.2514/1.a35670

Francesco Soranna, Patrick S. Heaney, Martin K. Sekula, David J. Piatak, James M. Ramey

{"title":"Space Launch System Unsteady Forces Developed from Unsteady-Pressure-Sensitive-Paint–Based Corcos Model Parameters","authors":"Francesco Soranna, Patrick S. Heaney, Martin K. Sekula, David J. Piatak, James M. Ramey","doi":"10.2514/1.a35670","DOIUrl":"https://doi.org/10.2514/1.a35670","url":null,"abstract":"During atmospheric ascent, launch vehicles (LVs) experience large dynamic loads at transonic conditions where aerodynamic buffet is most critical. To estimate buffet loads, coupled loads analyses typically utilize suitable forcing functions, called buffet forcing functions (BFFs). One of the key buffet environment contributors is the turbulent boundary layer (TBL) acting on the LV outer skin. The cross-spectral density function of TBL-induced fluctuating pressures can be estimated using the widely accepted Corcos model. In the context of transonic buffet, the performance of this model is not well established, partly because of lack of data. To fill this gap, NASA recently acquired extremely high-spatial-density data for the Space Launch System vehicle using the unsteady-pressure-sensitive-paint (uPSP) optical measurement technique. A methodology is developed for extraction of the Corcos model parameters using these unique data, with a focus on the LV design application. The model hypotheses are verified, and the model parameters are empirically tuned. For selected panels on the vehicle, force coherence factors are derived based on the Corcos model, and the associated panel BFFs are compared to uPSP data. It is shown that the modeled BFFs are in agreement with direct integration of uPSP data, except for regions where pressure fluctuations are spatially nonuniform. In those regions, the Corcos-based BFFs exhibit inherent limitations of BFF estimation methods that rely on discrete pressure measurements. Lastly, extending the present implementation of the Corcos model to frequencies impacted by vortex-shedding phenomena can result in underconservative BFF estimates at the subharmonic of the vortex shedding.","PeriodicalId":50048,"journal":{"name":"Journal of Spacecraft and Rockets","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135350655","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Tether System in Martian-Moons-eXploration-Like Mission for Phobos Surface Exploration 火卫一表面探测类火星卫星探测任务中的系绳系统

4区工程技术

Journal of Spacecraft and Rockets Pub Date : 2023-10-06 DOI: 10.2514/1.a35777

Vladimir S. Aslanov

引用次数: 1

Efficient Two-Way Coupled Analysis of Steady-State Particle-Laden Hypersonic Flows 满载粒子的高超声速稳态流动的高效双向耦合分析

4区工程技术

Journal of Spacecraft and Rockets Pub Date : 2023-10-04 DOI: 10.2514/1.a35731

Andrew Hinkle, Serhat Hosder, Christopher Johnston

引用次数: 0