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Progress of Radiation Belt exploration by a Constellation of Small Satellites TGCSS/SGRB, COSPAR

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空间科学学报 2024年第4期44卷 746-750页

作者： WU Ji YANG Xiaochao DAI Lei DENG Li National space Science center Chinese Academy of SciencesBeijing 100190

A COnstellation of Radiation BElt Survey(CORBES)program is proposed by the Sub-Group on Radiation Belt(SGRB)of TGCSS,*** address the open qustions about the dynamics of the Earth’s radiation belt,CORBES mission would use a constellation of small/CubeSats to take an ultra-fast survey of the Earth’s radiation *** concept,science objectives and preliminary technical design of CORBES are *** mission is an international multilateral cooperation mission coordinated by *** SGRB Science Activities and COSPAR HQs Coordinate Activities on CORBES are summaried.

关键词： Radiation belts Ultra-fast survey Constellation

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Origin of water in the Moon

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National Science Review 2024年第6期11卷 10-12页

作者： Hejiu Hui Ziyan Han Kang Shuai State Key Laboratory of Mineral Deposits Research & lunar and Planetary Science Institute School of Earth Sciences and Engineering Nanjing University CAS center for Excellence in Comparative Planetology CAS Key Laboratory of Earth and Planetary Physics Institute of Geology and Geophysics

It has been well known since the Apollo era that the Moon is relatively depleted in volatiles as a result of the Moonformation impact and the subsequent planetary differentiation. The lunar interior was believed to have been extremely dry [1]. The discovery of indigenous water (a collective term for H-bearing species OH, H2O, etc.) in various lunar materials [2–5] has driven a paradigm shift in our knowledge of water in the Moon, from a dry to a wet Moon.

关键词： lunar HYDROGEN TERRESTRIAL INTERIOR

spacecraft angular velocity estimation method using optical flow of stars

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Science China(Information Sciences) 2018年第11期61卷 99-112页

作者： Xiaolin NING Zonghe DING Pingping CHEN Weiren WU Jiancheng FANG Gang LIU School of Instrumentation Science & Opto-electronics Engineering Beihang University lunar exploration and space program center China National Space Administration

Angular velocity is a crucial parameter for spacecraft navigation, which, at present, is mainly obtained by using gyroscopes. Several studies have been performed on angular velocity estimation using star sensors when data from gyroscopes are not available. Most of the previous angular velocity estimation methods using star sensors are based on information on the attitude or star vector measurements. In this paper,an angular velocity estimation method using the optical flow(OF) directly from the star images is proposed,which, unlike the previous methods, requires star coordinates in two consecutive images only. Because the procedure of star identification is eliminated, the corresponding high computation requirement is *** demonstrate that the proposed method has a robust performance in terms of computational cost and the number of stars in the field of view(FOV) compared with the previous methods. Finally, certain affecting factors are analyzed, including lens distortion, star senor instantaneous FOV(IFOV), star number,and accuracy of the star sensor.

关键词： angular velocity star sensor optical flow star images Kalman filter

Return to the Moon:New perspectives on lunar exploration

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Science Bulletin 2024年第13期69卷 2136-2148页

作者： Yangting Lin Wei Yang Hui Zhang Hejiu Hui Sen Hu Long Xiao Jianzhong Liu Zhiyong Xiao Zongyu Yue Jinhai Zhang Yang Liu Jing Yang Honglei Lin Aicheng Zhang Dijun Guo Sheng Gou Lin Xu Yuyang He Xianguo Zhang Liping Qin Zongcheng Ling Xiongyao Li Aimin Du Huaiyu He Peng Zhang Jinbin Cao Xianhua Li Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China State Key Laboratory for Mineral Deposits Research and School of Earth Sciences and Engineering Nanjing UniversityNanjing 210023China State Key Laboratory of Geological Processes and Mineral Resources School of Earth SciencesChina University of GeosciencesWuhan 430074China Institute of Geochemistry Chinese Academy of SciencesGuiyang 550002China Planetary Environmental and Astrobiological Research Laboratory School of Atmospheric SciencesSun Yat-sen UniversityZhuhai 519082China National space Science center Chinese Academy of SciencesBeijing 100190China Deep space exploration Laboratory/CAS Key Laboratory of Crust-Mantle Materials and Environments University of Science and Technology of ChinaHefei 230026China Shandong Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesShandong UniversityWeihai 264209China Technology and Engineering center for space Utilization Chinese Academy of SciencesBeijing 100094China School of space and Environment Beihang UniversityBeijing 100191China

lunar exploration is deemed crucial for uncovering the origins of the Earth-Moon system and is the first step for advancing humanity’s exploration of deep *** the past decade,the Chinese lunar exploration program(CLEP),also known as the Chang’e(CE)Project,has achieved remarkable *** has successfully developed and demonstrated the engineering capability required to reach and return from the lunar ***,the CE Project has made historic firsts with the landing and on-site exploration of the far side of the Moon,along with the collection of the youngest volcanic samples from the Procellarum KREEP *** achievements have significantly enhanced our understanding of lunar *** on this success,China has proposed an ambitious crewed lunar exploration strategy,aiming to return to the Moon for scientific exploration and *** plan encompasses two primary phases:the first crewed lunar landing and exploration,followed by a thousand-kilometer scale scientific expedition to construct a geological cross-section across the lunar *** the limitations of current lunar exploration efforts and China’s engineering and technical capabilities,this paper explores the benefits of crewed lunar exploration while leveraging synergies with robotic *** study refines fundamental lunar scientific questions that could lead to significant breakthroughs,considering the respective engineering and technological *** research lays a crucial foundation for defining the objectives of future lunar exploration,emphasizing the importance of crewed missions and offering insights into potential advancements in lunar science.

关键词： Crewed lunar exploration Water and volatiles Composition and structure of lunar interior Volcanic activity and evolution of lunar mantle space weathering and radiation environments exploration technology

Angular velocity estimation using characteristics of star trails obtained by star sensor for spacecraft

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Science China(Information Sciences) 2021年第1期64卷 201-214页

作者： Xiaolin NING Pingping CHEN Yueqing HUANG Weiren WU Jiancheng FANG School of Instrumentation Science & Opto-electronics Engineering Beihang University lunar exploration and space program center China National Space Administration

Many studies have been conducted about angular velocity estimation using star sensors, and fairly good performance is achieved when the spacecraft is working at low-dynamic environments. However,when the spacecraft rotates at a large angular velocity, the star image will become blurred, which makes it difficult to identify and recognize star centroids, which, in turn, reduces the accuracy of angular velocity estimation. Therefore, to solve the problem with angular velocity estimation in highly dynamic situations,this research studies a method of angular velocity estimation using blurred star images. The length and ending point coordinates of star trails obtained from these blurred star images are used for a series of processes, which includes the pre-processing of blurred star images, determination of starting and ending points, thinning and selection of star trails, and calculation of trail lengths. Simulations show that the effectiveness of the proposed method in highly dynamic situations and the angular velocity estimation errors in constant and sinusoidal variation are reduced by at least 66% and 62%, respectively, compared with those of the traditional method.

关键词： angular velocity estimation star sensor blurred star images star trail characteristics unscented Kalman filter

Large-scale manufacturing of functional single-atom ink for convenient glucose sensing

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Nano Research 2024年第8期17卷 7256-7263页

作者： Muyu Yan Xiaofei Zhu Can Xiong Xiao Han Zhenggang Xue Yuen Wu Department of Endocrinology Institute of Endocrine and Metabolic DiseasesThe First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230001China Deep space exploration Laboratory University of Science and Technology of ChinaHefei 230026China NEST Laboratory Department of PhysicsDepartment of ChemistryCollege of ScienceShanghai UniversityShanghai 200444China center of Advanced Nanocatalysis(CAN) Department of Applied ChemistryUniversity of Science and Technology of ChinaHefei 230026China

Printing techniques hold great potential in the manufacture of electronics such as sensors,micro-supercapacitors,and flexible ***,developing large-scale functional conductive inks with appropriate rheological properties and active components still remains a ***,through optimizing the formulations of ink,iron single sites supported N-doped carbon black(Fe_(1)-NC)inks can serve as both conductive electrodes and high-reactive catalysts to realize convenient glucose detection,which pronouncedly reduces the dosage of enzyme and simplifies the sensors *** detail,utilizing in-situ pyrolysis method,Fe_(1)-NC single-atom catalysts(SACs)are prepared in bulk(dekagram-level).The batched Fe_(1)-NC SACs materials can be uniformly mixed with modulated ink to realize the screen printing with high resolution and ***,the whole scalable preparation and ink-functional process can be extended to various metals(including Co,Ni,Cu,and Mn).The introduction of highly active Fe_(1)-NC sites reduces the amount of enzyme used in glucose detection by at least 50%,contributing to the cost reduction of *** strategy in harnessing the SACs onto the carbon inks thus provides a broad prospect for the low-cost and large-scale printing of sensitive sensing devices.

关键词： large-scale manufacturing single-atom inks screen printing glucose sensing low enzyme dosage

Ensemble successor representations for task generalization in offline-to-online reinforcement learning

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Science China(Information Sciences) 2024年第7期67卷 240-255页

作者： Changhong WANG Xudong YU Chenjia BAI Qiaosheng ZHANG Zhen WANG space Control and Inertial Technology Research center Harbin Institute of Technology Shanghai Artificial Intelligence Laboratory Shenzhen Research Institute of Northwestern Polytechnical University School of Cybersecurity Northwestern Polytechnical University

In reinforcement learning(RL), training a policy from scratch with online experiences can be inefficient because of the difficulties in exploration. Recently, offline RL provides a promising solution by giving an initialized offline policy, which can be refined through online interactions. However, existing approaches primarily perform offline and online learning in the same task, without considering the task generalization problem in offline-to-online adaptation. In real-world applications, it is common that we only have an offline dataset from a specific task while aiming for fast online-adaptation for several tasks. To address this problem, our work builds upon the investigation of successor representations for task generalization in online RL and extends the framework to incorporate offline-to-online learning. We demonstrate that the conventional paradigm using successor features cannot effectively utilize offline data and improve the performance for the new task by online fine-tuning. To mitigate this, we introduce a novel methodology that leverages offline data to acquire an ensemble of successor representations and subsequently constructs ensemble Q functions. This approach enables robust representation learning from datasets with different coverage and facilitates fast adaption of Q functions towards new tasks during the online fine-tuning *** empirical evaluations provide compelling evidence showcasing the superior performance of our method in generalizing to diverse or even unseen tasks.

关键词： offline reinforcement learning online fine-tuning task generalization successor representations ensembles

Design of communication relay mission for supporting lunar-farside soft landing

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Science China(Information Sciences) 2018年第4期61卷 73-86页

作者： Weiren WU Yuhua TANG Lihua ZHANG Dong QIAO lunar exploration program and space Engineering center School of Aerospace Engineering Beijing Institute of Technology Dong Fang Hong Satellite Co.Ltd. Key Laboratory of Autonomous Navigation and Control for Deep space exploration Ministry of Industry and Information Technology

Chang’E-IV will be the first soft-landing and rover mission on the lunar farside. The relay satellite, which is located near the Earth-Moon L2 point for relay communication, is the key to the landing mission. Based on an analysis of the characteristics of the task and the technical difficulties associated with the relay satellite system, the overall design scheme of the relay communication mission is proposed in terms of trajectory design and communication system design among other aspects. First, according to the complex dynamic environment, a mission orbit that serves as an uninterrupted communication link is presented. A short-duration and low-energy transfer trajectory with lunar flyby is discussed. Orbital correction and a low-cost control strategy for orbit maintenance in the Earth-Moon L2 point region are provided. Second,considering the existing technical constraints, the requirement of relay communication in different stages and the design schemes of frequency division and redundant relay communication system are introduced. Finally,based on the trajectory design index and the performance of the communication system, the overall design scheme of the relay communication mission is proposed. This mission will provide the technical support and reference required for the Chang’E-IV mission.

关键词： lunar farside soft landing relay communication Earth-Moon Lagrange point

Multiphysics simulation and optimization of the in-situ beneficiation process of ilmenite minerals from lunar regolith

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Science China Earth Sciences 2024年

作者： Peng ZHANG Xin LIU Guanghui LIU Wei DAI Hanzhe YANG Haibo ZHENG Zhi WANG Ran NIU Yifan BAI Yang ZHANG Chengbao LIU Ge YANG Junwei YANG Guang ZHANG Technology and Engineering center for space Utilization Chinese Academy of Sciences Beijing Hegong Simulation Co. Ltd

The exploration and utilization of lunar resources have become the major objectives of future lunar exploration missions. The classified collection and processing of lunar minerals is the basic prerequisite for the in-situ exploration and utilization of lunar resources. In this study, we propose a scheme for in-situ separation of magnetic minerals from lunar soils using the dry magnetic separation method. The scheme can realize the purpose of separating magnetic minerals from lunar regolith by altering the motion trajectory of lunar regolith particles with different magnetic properties. Detailed modeling of the dry magnetic separation device is conducted, and the three-dimensional distribution of magnetic parameters is calculated and analyzed. Based on the characterization and analysis of the ChangE-5’s samples, the morphologies and physical parameters of lunar regolith particles are modeled and simulated. A discrete element simulation of the motion process of lunar regolith particles under multi-physical field conditions is performed, and the influences of key parameters on the beneficiation performance of lunar magnetic minerals are investigated. Our results indicate that optimal separation and beneficiation of lunar regolith particles can be achieved under specific conditions of magnetic field strength and drum speed. Additionally, we analyze the effects of lunar weak gravity conditions and the charged nature of lunar particles on the beneficiation process, showing that these factors can obviously enhance the beneficiation process of lunar ilmenites. This study demonstrates the feasibility of using the dry magnetic separation method for the beneficiation of magnetic minerals from lunar regolith, providing a theoretical basis for the scientific tasks of collecting, processing, and utilizing lunar mineral resources.

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