In recent years,the rapid development of mega-constellations has significantly exacerbated the deterioration of the space debris environment,posing substantial and escalating threats to the safety of spacecraft.This s...In recent years,the rapid development of mega-constellations has significantly exacerbated the deterioration of the space debris environment,posing substantial and escalating threats to the safety of spacecraft.This study aims to explore the complex evolution of the space debris environment and assess the collision risks associated with spacecraft.First,a space debris environment topological network model is proposed,which incorporates interdisciplinary methods from topological networks,fluid mechanics,and spacecraft dynamics.This model enables a structured representation of the relationships among space objects and provides rapid predictions of the space debris environment.Then,a collision probability algorithm based on the topological network model is introduced.This algorithm inherits the efficiency advantages of the topological network model and has been validated for reliability through comparison with the classical ESA’s DRAMA software.Finally,based on the above models,the collision risks of constellation satellites in Low Earth Orbit(LEO)are analyzed,including both operational and deorbit processes.The study reveals that constellation satellites face a much higher risk of internal collisions with satellites from the same constellation during operations than that with other space objects.Additionally,during the satellite deorbit process,the collision risk peaks when satellites traverse the operational region of Starlink satellites.展开更多
The net capturing method holds great potential for space debris removal due to its adaptability to the various target shapes and high fault tolerance.However,the capture mechanisms of current rope nets,which rely sole...The net capturing method holds great potential for space debris removal due to its adaptability to the various target shapes and high fault tolerance.However,the capture mechanisms of current rope nets,which rely solely on a passive wrap-ping mechanism,limit their capacity to capture objects within a specific size range and make it challenging to handle unexpected situations.Inspired by spider webs,which combine wrapping and adhering to capture prey of various sizes,we present a new type of net(envelope diameter:208.49 mm)for on-orbit capture.This net adopts a spiral symmetric structure similar to spider webs,incorporates electrostatic-microstructure hybrid adhesives,and increases the maximum contact area by 38.31%,allowing it to capture debris ranging from fragments smaller than the mesh size(envelope diam-eter:2.7 mm-4.4 mm)to larger objects(envelope diameter:270 mm),and effectively grasps flexible items(450 mm2),planar items(350 mm2)and three-dimensional items(160 mm3).Moreover,to validate the net's capability for wrapping and adhesion,simulations and experiments are demonstrated that this dual capture method can effectively handle various targets.展开更多
The threat posed by space debris to space security is continuously increasing.Optical observation is the main detection method for space debris,but the variety of observation geometries in available measurement datase...The threat posed by space debris to space security is continuously increasing.Optical observation is the main detection method for space debris,but the variety of observation geometries in available measurement datasets is limited.Therefore,simulations are required to supplement observational data.Hardware-in-the-loop(HIL)simulations can provide high-quality simulated optical detection data at a reasonable cost,but existing hardware-in-the-loop methods are only adapted to simple motion scenarios.To extend the simulation ability to complex space motion scenarios,here we propose an optical hardware-in-the-loop space debris simulation method,relying on dynamic detection scenarios,that uses a collaborative scenario-modality-feature simulation scheme to simulate variable observation geometries and to obtain sequential space debris simulation data covering a variety of modalities and scenarios.We apply the proposed space debris detection method to ground-based and space-based simulation experiments and analyze target features within the simulated detection data to demonstrate the usefulness of such simulations.Our simulation method is applicable to space debris optical detection under diverse observation conditions and to multidimensional space debris feature characterization.展开更多
Non-contact debris removal methods are fuel-efficient in a single operation compared to contact-based strategies as spacecraft don’t need to match debris velocity.To comprehensively analyze this scheme,maneuvering sc...Non-contact debris removal methods are fuel-efficient in a single operation compared to contact-based strategies as spacecraft don’t need to match debris velocity.To comprehensively analyze this scheme,maneuvering schemes for maximum debris removal with minimum fuel consumption,including task assignment,sequence planning,and trajectory planning,must be formulated.The coupling between variables’dimensions and optimization results in task assignment poses challenges,as debris removal is repetitive and uncertain,leading to a vast search space.This paper proposes a novel Greedy Randomized Adaptive Search Procedure with Large Neighborhood and Crossover Mechanisms(GRASP-LNCM)to address this problem.The hybrid dynamic iteration mechanism improves computational efficiency and enhances the optimality of results.The model innovatively considers unsuccessful single removal by using a quantitative method to assess removal percentage.In addition,to improve the efficiency of sequence and trajectory planning,a Suboptimal Search Algorithm(SSA)based on the Lambert property and accelerated Multi-Revolution Lambert Problem(MRLP)solving strategy is established.Finally,a real Iridium-33 debris removal mission is studied.The simulation demonstrates that the proposed algorithm achieves state-of-the-art performance in several typical scenarios.Compared to the contact-based scheme,the new one is simpler,saving more fuel under certain conditions.展开更多
基金supported by the National Level Project of China(No.KJSP2023020201)the Foundation of Science and Technology on Aerospace Flight Dynamics Laboratory of China(No.kjw6142210240202)+1 种基金the Beijing Institute of Technology Research Fund Program for Young Scholars of Chinathe Fundamental Research Funds for Central Universities of China。
文摘In recent years,the rapid development of mega-constellations has significantly exacerbated the deterioration of the space debris environment,posing substantial and escalating threats to the safety of spacecraft.This study aims to explore the complex evolution of the space debris environment and assess the collision risks associated with spacecraft.First,a space debris environment topological network model is proposed,which incorporates interdisciplinary methods from topological networks,fluid mechanics,and spacecraft dynamics.This model enables a structured representation of the relationships among space objects and provides rapid predictions of the space debris environment.Then,a collision probability algorithm based on the topological network model is introduced.This algorithm inherits the efficiency advantages of the topological network model and has been validated for reliability through comparison with the classical ESA’s DRAMA software.Finally,based on the above models,the collision risks of constellation satellites in Low Earth Orbit(LEO)are analyzed,including both operational and deorbit processes.The study reveals that constellation satellites face a much higher risk of internal collisions with satellites from the same constellation during operations than that with other space objects.Additionally,during the satellite deorbit process,the collision risk peaks when satellites traverse the operational region of Starlink satellites.
基金the New Chongqing Innovative Young Talent Project under Grant 2024NSCQ-qncxX0468Dreams Foundation of Jianghuai Advance Technology Center under Grant 2023-ZM01Z007.
文摘The net capturing method holds great potential for space debris removal due to its adaptability to the various target shapes and high fault tolerance.However,the capture mechanisms of current rope nets,which rely solely on a passive wrap-ping mechanism,limit their capacity to capture objects within a specific size range and make it challenging to handle unexpected situations.Inspired by spider webs,which combine wrapping and adhering to capture prey of various sizes,we present a new type of net(envelope diameter:208.49 mm)for on-orbit capture.This net adopts a spiral symmetric structure similar to spider webs,incorporates electrostatic-microstructure hybrid adhesives,and increases the maximum contact area by 38.31%,allowing it to capture debris ranging from fragments smaller than the mesh size(envelope diam-eter:2.7 mm-4.4 mm)to larger objects(envelope diameter:270 mm),and effectively grasps flexible items(450 mm2),planar items(350 mm2)and three-dimensional items(160 mm3).Moreover,to validate the net's capability for wrapping and adhesion,simulations and experiments are demonstrated that this dual capture method can effectively handle various targets.
基金supported by the Special funding project for space debris and Near-Earth Asteroids defense research(KJSP2023020202).
文摘The threat posed by space debris to space security is continuously increasing.Optical observation is the main detection method for space debris,but the variety of observation geometries in available measurement datasets is limited.Therefore,simulations are required to supplement observational data.Hardware-in-the-loop(HIL)simulations can provide high-quality simulated optical detection data at a reasonable cost,but existing hardware-in-the-loop methods are only adapted to simple motion scenarios.To extend the simulation ability to complex space motion scenarios,here we propose an optical hardware-in-the-loop space debris simulation method,relying on dynamic detection scenarios,that uses a collaborative scenario-modality-feature simulation scheme to simulate variable observation geometries and to obtain sequential space debris simulation data covering a variety of modalities and scenarios.We apply the proposed space debris detection method to ground-based and space-based simulation experiments and analyze target features within the simulated detection data to demonstrate the usefulness of such simulations.Our simulation method is applicable to space debris optical detection under diverse observation conditions and to multidimensional space debris feature characterization.
基金co-supported by the National Natural Science Foundation of China(Nos.U23B6001,62273118,12150008)the Fundamental Research Funds for the Central Universities,China(No.2023FRFK02043)+1 种基金the Natural Science Foundation of Heilongjiang Province,China(No.LH2022F023)China Aerospace Science and Technology Corporation Youth Talent Support Program.
文摘Non-contact debris removal methods are fuel-efficient in a single operation compared to contact-based strategies as spacecraft don’t need to match debris velocity.To comprehensively analyze this scheme,maneuvering schemes for maximum debris removal with minimum fuel consumption,including task assignment,sequence planning,and trajectory planning,must be formulated.The coupling between variables’dimensions and optimization results in task assignment poses challenges,as debris removal is repetitive and uncertain,leading to a vast search space.This paper proposes a novel Greedy Randomized Adaptive Search Procedure with Large Neighborhood and Crossover Mechanisms(GRASP-LNCM)to address this problem.The hybrid dynamic iteration mechanism improves computational efficiency and enhances the optimality of results.The model innovatively considers unsuccessful single removal by using a quantitative method to assess removal percentage.In addition,to improve the efficiency of sequence and trajectory planning,a Suboptimal Search Algorithm(SSA)based on the Lambert property and accelerated Multi-Revolution Lambert Problem(MRLP)solving strategy is established.Finally,a real Iridium-33 debris removal mission is studied.The simulation demonstrates that the proposed algorithm achieves state-of-the-art performance in several typical scenarios.Compared to the contact-based scheme,the new one is simpler,saving more fuel under certain conditions.
