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Acta Mechanica Solida Sinica 2022年第5期35卷 813-823页

作者： Jiayue Wang Yin Yu zhongcheng mu Yile Hu Aerospace Structure Research Center School of Aeronautics and AstronauticsShanghai Jiao Tong UniversityShanghai200240China School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai200240China

The effect of micro-void on transverse stiffness and strength for fiber-reinforced composites subjected to load perpendicular to fiber is studied using the state-based peridynamic(PD)*** heterogeneous microstructure with micro-voids are discretized with irregular and non-uniform grids on *** PD representative volume element with randomly distributed and sized micro-voids has been established with periodic boundary conditions.A parametric study was performed to evaluate the effects of void fraction and void size on transverse *** was found that the transverse modulus decreases with the void fraction in the range of 0.5–2%.A smaller void has a greater impact on the transverse modulus than a larger void under the same void *** crack growth path for the multi-fiber model subjected to transverse tension was *** PD predictions show that cracks initiate at the interface between fiber and matrix,then deflect to the micro-voids *** PD predictions match well with the analytical and experimental observations available in the literature.

关键词： State-based peridynamics Micro-void Non-uniform discretization Periodic boundary condition Transverse mechanical property

Meso-Scale Modeling for Effective Properties in Continuous Fiber-Reinforced Composites by State-Based Peridynamics

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Acta Mechanica Solida Sinica 2021年第5期34卷 729-742页

作者： Xiang Li Yin Yu zhongcheng mu Y.L.Hu Aerospace Structure Research Center School of Aeronautics and AstronauticsShanghai Jiao Tong UniversityShanghai200240China School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai200240China

This study demonstrates a homogenization approach via a modified state-based peridynamic(PD)method to predict the effective elastic properties of composite materials with periodic *** procedure of modeling the PD unit cell(UC)of continuous fiber-reinforced composite is *** boundary conditions are derived and implemented through the Lagrange multiplier method.A matrix-dominated approach for modeling the interphase properties between dissimilar materials is *** periodicity and continuity assumptions are employed to determine the stress and strain fields,as well as the effective elastic *** PD-UCs of square and hexagonal packs as well as the 0/90 laminate microstructure are modeled and compared with the analytical,numerical and experimental results from the *** agreement of predicted effective properties can be *** other PD homogenization approaches,the effective material properties can be directly and individually obtained from simple loading conditions.

关键词： State-based peridynamics Composites Meso-scale Unit Cell Homogenization

Sequential dynamic resource allocation in multi-beam satellite systems:A learning-based optimization method

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Chinese Journal of Aeronautics 2023年第6期36卷 288-301页

作者： Yixin HUANG Shufan WU Zhankui ZENG Zeyu KANG zhongcheng mu Hai HUANG School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai 200240China Shanghai Academy of Spaceflight Technology Shanghai 200240China School of Astronautics Beihang UniversityBeijing 100191China

multi-beam antenna and beam hopping technologies are an effective solution for scarce satellite frequency *** of the primary challenges accompanying with multi-Beam Satellites(MBS)is an efficient Dynamic Resource Allocation(DRA)*** paper presents a learning-based Hybrid-Action Deep Q-Network(HADQN)algorithm to address the sequential decision-making optimization problem in *** using a parameterized hybrid action space,HADQN makes it possible to schedule the beam pattern and allocate transmitter power more *** pursue multiple long-term QoS requirements,HADQN adopts a multi-objective optimization method to decrease system transmission delay,loss ratio of data packets and power consumption load *** results demonstrate that the proposed HADQN algorithm is feasible and greatly reduces in-orbit energy consumption without compromising QoS performance.

关键词： Beam hopping Deep reinforcement learning Dynamic resource allocation Mixed-integer programming multi-beam satellite systems multi-objective optimization

Attitude control of multi-spacecraft systems on SO(3)with stochastic links failure

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Chinese Journal of Aeronautics 2024年第3期37卷 320-331页

作者： KANG Zeyu SHEN Qiang WU Shufan Chris J.DAMAREN mu zhongcheng School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai 200240China Institute for Aerospace Studies University of TorontoTorontoOntario M3H 5T6Canada

In this paper,for multi-Spacecraft System(MSS)with a directed communication topology link and a static virtual leader,a controller is proposed to realize attitude consensus and attitude stabilization with stochastic links failure and actuator ***,an MSS attitude error model suitable for a directed topology link and with a static virtual leader based on SO(3)is derived,which considers that the attitude error on SO(3)cannot be defined based on algebraic ***,we design a controller to realize the MSS on SO(3)with attitude consensus and attitude stabilization under stochastic links failure and actuator ***,the simulation results of a multi-spacecraft system with stochastic links failure and a static virtual leader spacecraft are demonstrated to illustrate the efficiency of the attitude controller.

关键词： multi-spacecraft systems Attitude consensus Attitude stabilization Stochastic links failure Super-martingale convergence

Reinforcement learning based dynamic distributed routing scheme for mega LEO satellite networks

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Chinese Journal of Aeronautics 2023年第2期36卷 284-291页

作者： Yixin HUANG Shufan WU Zeyu KANG zhongcheng mu Hai HUANG Xiaofeng WU Andrew Jack TANG Xuebin CHENG School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai 200240China School of Astronautics Beihang UniversityBeijing 100191China School of Aerospace Mechanical and Mechatronic EngineeringThe University of SydneyCamperdown 2006Australia X-Laboratory The Second Academy of China Aerospace Science and Industry CorporationBeijing 100854China

Recently,mega Low Earth Orbit(LEO)Satellite Network(LSN)systems have gained more and more attention due to low latency,broadband communications and global coverage for ground *** of the primary challenges for LSN systems with inter-satellite links is the routing strategy calculation and maintenance,due to LSN constellation scale and dynamic network topology *** order to seek an efficient routing strategy,a Q-learning-based dynamic distributed Routing scheme for LSNs(QRLSN)is proposed in this *** achieve low end-toend delay and low network traffic overhead load in LSNs,QRLSN adopts a multi-objective optimization method to find the optimal next hop for forwarding data *** results demonstrate that the proposed scheme can effectively discover the initial routing strategy and provide long-term Quality of Service(QoS)optimization during the routing maintenance *** addition,comparison results demonstrate that QRLSN is superior to the virtual-topology-based shortest path routing algorithm.

关键词： LEO satellite networks Mega constellation multi-objective optimization Routing algorithm Reinforcement learning

Displaced Sun-Synchronous Orbit Control Scheme for Sailcraft 36

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Displaced Sun-Synchronous Orbit Control Scheme for Sailcraft

第36届中国控制会议

作者： XIA Xiwang ZHANG Keke CHEN Hongyu CHEN Yingbo Zhou Meijiang LI Chaoyong mu zhongcheng LIU Shanwu Shanghai Engineering Center for Microsatellites Chinese Academy of Sciences Key Lab of Microsatellites Chinese Academy of Sciences Shanghai Institute of Microsystem and Information Technology University of Chinese Academy of Sciences College of Electrical Engineering Zhejiang University

ISBN: (纸本)9781538629185

Displaced Sun-Synchronous orbit（DSSO） is names as the orbit with the same orbital parameters but the paralleled orbital plane with the Sun-synchronous *** the solar pressure and the universal gravitation,the orbit could *** this paper,the principle corresponding to orbit suspension is deduced,the orbit injection scheme is presented and the orbit keeping scheme is *** results indicate that the scheme is effective and the sailcraft could enter into the displaced Sun-synchronous orbit by employing the solar pressure and the universal gravitation.

关键词： SailCraft Solar Sail Displaced Sun-Synchronous Orbit(DSSO) Orbit Suspension Orbit Keeping

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纳卫星电磁对接机构技术

北京航空航天大学学报 2018年第12期44卷 2644-2650页

作者：慕忠成叶东吴树范上海交通大学航空航天学院上海200240 哈尔滨工业大学航天学院哈尔滨150001

在轨服务是未来卫星主要发展趋势之一,在轨软件重构和硬件重构技术是其主要核心技术。基于此,首先创新移植电磁原理和"笔帽式"锁紧原理,提出了一种适用于立方体纳卫星的1U微型电磁对接硬件重构设计方案。然后,基于所设计的电磁对接机构... 详细信息

在轨服务是未来卫星主要发展趋势之一,在轨软件重构和硬件重构技术是其主要核心技术。基于此,首先创新移植电磁原理和"笔帽式"锁紧原理,提出了一种适用于立方体纳卫星的1U微型电磁对接硬件重构设计方案。然后,基于所设计的电磁对接机构,通过电磁力和力矩精确模型和远场模型的比较分析,明确了远场模型适用范围为对接距离大于0. 1 m。最后,利用数值仿真方法,分析得到单个线圈和含铁芯的通电螺线管比值约在10-8～10-4量级,为远场模型的修正提供参考。

关键词：纳卫星在轨重构电磁对接螺线管线圈非线性

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卵形头弹体对素混凝土高速侵彻的实验研究

应用力学学报 2019年第5期36卷 1144-1151,1262页

作者：邓云飞崔亚男慕忠成冯正兴彭捷中国民航大学航空工程学院天津300300 上海交通大学航空航天学院上海200240

利用二级轻气炮装置,选取材料为38CrMnSi的卵形头弹对素混凝土靶体进行了撞击实验。根据得到的实验数据以及实验后回收的弹体和靶体,分析了动能弹高速侵彻素混凝土时的弹靶响应特性,包括弹体质量损失规律及其机理、靶体损伤特征和侵彻... 详细信息

利用二级轻气炮装置,选取材料为38CrMnSi的卵形头弹对素混凝土靶体进行了撞击实验。根据得到的实验数据以及实验后回收的弹体和靶体,分析了动能弹高速侵彻素混凝土时的弹靶响应特性,包括弹体质量损失规律及其机理、靶体损伤特征和侵彻深度随速度的变化规律。结果分析表明,弹体侵彻素混凝土靶体过程包括锥型弹坑阶段和隧道稳定阶段,从较低速到高速侵彻,弹体发生了CRH变小、头部半球化和锥形化的特征性现象,并伴随着不同程度的质量损失,由此引发侵彻深度在高速侵彻时较小的波动。进一步引用弹体侵彻混凝土靶响应模型进行了理论分析,发现在较低速撞击时,利用模型计算得到的值与实验结果比较吻合,而高速撞击条件下偏差则较大,需要考虑弹体头部形状变化对侵彻响应结果的影响。

关键词：素混凝土侵彻质量损失侵彻深度理论模型

伴随卫星轨控时机与相对运动椭圆大小控制效率的关系

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载人航天 2013年第5期19卷 90-96页

作者：吴会英陈宏宇周美江慕忠成上海微小卫星工程中心上海201203

基于相对运动理论,研究了同轨道面内伴随卫星的轨控时机对相对运动椭圆大小改变效率的影响,并用仿真实例进行了验证,证明在相对椭圆上、下点平行于相对运动方向控制对相对运动椭圆大小的改变效率最高;然后以主航天器伴随卫星释放后的轨... 详细信息

基于相对运动理论,研究了同轨道面内伴随卫星的轨控时机对相对运动椭圆大小改变效率的影响,并用仿真实例进行了验证,证明在相对椭圆上、下点平行于相对运动方向控制对相对运动椭圆大小的改变效率最高;然后以主航天器伴随卫星释放后的轨道驻留为例,应用这一理论求解了燃料最省的轨控策略。

关键词：伴随卫星相对运动轨道控制

新工科背景下的“科研+科创”课程探索与实践

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创新创业理论研究与实践 2024年第5期7卷 80-83页

作者：张晓晖吕新颖余文胜张斌蒋东杰慕忠成上海交通大学航空航天学院上海201201

该文以2022年首次开设的航空航天工程科创课程为例,介绍了上海交通大学航空航天学院对于“科研+科创”类型新模式课程的探索。航空航天工程科创以“寓学于研”为内容设计核心,以解决问题为导向,通过将科研题目和科创项目引入低年级课程... 详细信息

该文以2022年首次开设的航空航天工程科创课程为例,介绍了上海交通大学航空航天学院对于“科研+科创”类型新模式课程的探索。航空航天工程科创以“寓学于研”为内容设计核心,以解决问题为导向,通过将科研题目和科创项目引入低年级课程课堂,将立德树人和创新人才培养目标有机契合,实现科研能力与创新能力培养的有机统一。

关键词：航空航天实践教学科研科创科创课程立德树人