It is widely known that the hypervelocity impact of orbital debris can cause serious damage to spacecraft,and enhancing the impact resistance is the great concern of spacecraft shield design.This paper provides a comp...It is widely known that the hypervelocity impact of orbital debris can cause serious damage to spacecraft,and enhancing the impact resistance is the great concern of spacecraft shield design.This paper provides a comprehensive overview of advances in the development of bumper materials for spacecraft shield applications.In particular,the protective mechanism and process of the bumper using different materials against hypervelocity impact are reviewed and discussed.The advantages and disadvantages of each material used in shield were discussed,and the performance under hypervelocity impact was given according to the specific configuration.This review provides the useful reference and basis for researchers and engineers to create bumper materials for spacecraft shield applications,and the contemporary challenges and future directions for bumper materials for spacecraft shield were presented.展开更多
提出一种改进的初轨确定算法,基于动态阈值的距离搜索方法,以改进传统算法在处理数据时初轨成功率和初轨误差。通过动态调整搜索阈值,旨在实现更精准和高效的初轨确定,以满足当前对空间目标初轨确定的需求;利用LEO,MEO和GEO目标的实测...提出一种改进的初轨确定算法,基于动态阈值的距离搜索方法,以改进传统算法在处理数据时初轨成功率和初轨误差。通过动态调整搜索阈值,旨在实现更精准和高效的初轨确定,以满足当前对空间目标初轨确定的需求;利用LEO,MEO和GEO目标的实测角度数据开展算法测试。介绍了基于动态阈值的距离搜索算法的实现过程,基于数据处理的经验,用动态阈值实现初轨参数质量控制环节的轨道筛选。给出了详细的算法实现流程。利用TLE(Two Line El⁃ements)评估了初轨确定参数误差。基于“烛龙”观测网的中低轨目标和中国科学院长春人造卫星观测站的高轨目标的实测角度数据,开展算法测试。结果表明:LEO,MEO和GEO目标短弧初轨确定成功率分别约为94%,75%和89%,半长轴误差均值分别约为9,12和50 km。该算法适用性强、成功率高、定轨精度高,证明了监测数据的质量。展开更多
With the rapid development of space activities,non-cooperative space targets increase swiftly,such as failed satellites and upper stages,threating normal spacecrafts seriously.As there are some problems in the capture...With the rapid development of space activities,non-cooperative space targets increase swiftly,such as failed satellites and upper stages,threating normal spacecrafts seriously.As there are some problems in the capture process,such as excessive collision and fast tumbling of targets,manipulator with redundant Degrees of Freedom(DOFs)can be used to improve the compliance and therefore solve these problems.The Rope-Driven Snake Manipulator(RDSM)is a combina-tion of hyper-redundant DOFs and better compliance,and therefore it is suitable for capturing mis-sion.In this paper,a snake manipulator mechanism is designed,and the complete kinematic model and system dynamic model considering RDSM,target and contact is established.Then,to obtain the configuration of joint with hyper-redundant DOFs,an improved motion dexterity index is pro-posed as the joint motion optimization target.Besides,the force-position collaborative optimization index is designed to adjust active stiffness,and the impedance control method based on the modified index is used to capture the space target.Finally,the proposed force-position collaborative opti-mization method is verified by virtual prototype co-simulation.The results demonstrate that based on the proposed method,the collision force is reduced by about 25%compared to normal impe-dance control,showing higher safety.展开更多
基金supported by National Natural Science Foundation of China(Grant Nos.12202068,12202087)China National Space Administration Preliminary Research Project(Grant Nos.KJSP2023020201,KJSP2020010402).
文摘It is widely known that the hypervelocity impact of orbital debris can cause serious damage to spacecraft,and enhancing the impact resistance is the great concern of spacecraft shield design.This paper provides a comprehensive overview of advances in the development of bumper materials for spacecraft shield applications.In particular,the protective mechanism and process of the bumper using different materials against hypervelocity impact are reviewed and discussed.The advantages and disadvantages of each material used in shield were discussed,and the performance under hypervelocity impact was given according to the specific configuration.This review provides the useful reference and basis for researchers and engineers to create bumper materials for spacecraft shield applications,and the contemporary challenges and future directions for bumper materials for spacecraft shield were presented.
文摘提出一种改进的初轨确定算法,基于动态阈值的距离搜索方法,以改进传统算法在处理数据时初轨成功率和初轨误差。通过动态调整搜索阈值,旨在实现更精准和高效的初轨确定,以满足当前对空间目标初轨确定的需求;利用LEO,MEO和GEO目标的实测角度数据开展算法测试。介绍了基于动态阈值的距离搜索算法的实现过程,基于数据处理的经验,用动态阈值实现初轨参数质量控制环节的轨道筛选。给出了详细的算法实现流程。利用TLE(Two Line El⁃ements)评估了初轨确定参数误差。基于“烛龙”观测网的中低轨目标和中国科学院长春人造卫星观测站的高轨目标的实测角度数据,开展算法测试。结果表明:LEO,MEO和GEO目标短弧初轨确定成功率分别约为94%,75%和89%,半长轴误差均值分别约为9,12和50 km。该算法适用性强、成功率高、定轨精度高,证明了监测数据的质量。
文摘With the rapid development of space activities,non-cooperative space targets increase swiftly,such as failed satellites and upper stages,threating normal spacecrafts seriously.As there are some problems in the capture process,such as excessive collision and fast tumbling of targets,manipulator with redundant Degrees of Freedom(DOFs)can be used to improve the compliance and therefore solve these problems.The Rope-Driven Snake Manipulator(RDSM)is a combina-tion of hyper-redundant DOFs and better compliance,and therefore it is suitable for capturing mis-sion.In this paper,a snake manipulator mechanism is designed,and the complete kinematic model and system dynamic model considering RDSM,target and contact is established.Then,to obtain the configuration of joint with hyper-redundant DOFs,an improved motion dexterity index is pro-posed as the joint motion optimization target.Besides,the force-position collaborative optimization index is designed to adjust active stiffness,and the impedance control method based on the modified index is used to capture the space target.Finally,the proposed force-position collaborative opti-mization method is verified by virtual prototype co-simulation.The results demonstrate that based on the proposed method,the collision force is reduced by about 25%compared to normal impe-dance control,showing higher safety.
