Subjects -> AERONAUTICS AND SPACE FLIGHT (Total: 124 journals)
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- Orbital Rendezvous Guidance Strategy for Time-Sensitive Missions
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Abstract: Abstract A fixed-time orbital rendezvous guidance strategy was proposed to meet the requirements of the time-sensitive pursuit-capture game mission. A key problem of fixed-time orbit rendezvous is the design of deceleration guidance strategy and the choice of transfer time. In order to solve the deceleration guidance problem under limited thrust, a displacement formula under constant rocket thrust is proposed. Basing on the formula, a deceleration guidance strategy of "pulse correction, deceleration condition, inverse-relative-velocity deceleration" was designed so that the spacecraft can meet the terminal position constraint. Basing on the formula, a deceleration guidance strategy of "pulse correction, deceleration condition, inverse-relative-velocity deceleration" was designed so that the spacecraft can meet the terminal position constraint. For the mission time delay caused by deceleration process, a differential correction method was designed based on the displacement formula, which can obtain the Lambert transfer time corresponding to a given mission time. With the proposed method, the mission time error is reduced less than 1 s. PubDate: 2024-08-17
- Multi-satellite Capture Configuration with Continuous Thrust
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Abstract: Abstract The pursuit-evasion game of orbital satellite is an important research problem in the field of space security. In this pursuit-evasion game, intercepting the target usually requires superior maneuvering capabilities. To address this issue, a method is proposed in this paper to use multiple small satellites with weaker maneuvering capabilities to encircle and capture larger targets with stronger maneuvering abilities. Firstly, based on Tsiolkovsky’s formula, the planar interception problem is derived and a one-on-one planar interception strategy is designed. Next, the existence of solutions for planar mission is analyzed, and a multi-satellite encirclement configuration is designed based on elliptical passive flyby theory. Finally, simulation analysis is conducted on the impact of various design parameters of the planar interception configuration on the encirclement task. The results indicate that the initial distance between interceptor and target significantly affects interception time. Simulation results validate that the proposed interception strategy and encirclement configuration can achieve rapid interception of close-range targets effectively. PubDate: 2024-08-16
- A Conflict-Priority-Based Variable Neighborhood Tabu Search Method for
Multi-satellite Scheduling-
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Abstract: Abstract With the increasing number and capabilities of orbital satellites and their onboard sensors, satellites scheduling plays an important role in growing demands for Earth observation tasks. A conflict-priority-based variable neighborhood tabu search method is proposed in this paper. By analyzing the flexibility of resources, the conflict-priority of tasks, and the visible time window features, the indicators of the impact, the conflict, the flexibility, and the bad impact are first established. On this basis, a first-come first-served greedy algorithm and a minimum bad impact greedy algorithm are designed for the generation of the initial solution. some rule-based heuristic strategies are also adopted for optimizing. Additionally, the algorithm incorporates three types of neighborhood structures including insertion, swapping and rearrangement, and deletion, using a tabu list to avoid local optima. Experimental results indicate the validity and efficiency of the proposed method. All solutions are within 10% of the optimal solution, with some even within 5%.The proposed method is effective for obtaining optimum solutions or solutions with a very good quality in various multi-satellite scheduling scenarios of realistic planning. PubDate: 2024-07-26
- Distributed Constrained Control Allocation for Attitude Takeover of
Combined Spacecraft-
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Abstract: Abstract The properties of control allocation for attitude takeover of a failed spacecraft using nanosatellites are investigated in this paper. Since each nanosatellite with thrusters can only provide a two-axis torque on the combined system, multi-nanosatellites are distributed on different positions of the failed spacecraft to achieve three-axis attitude control. Considering there is no centralized node to calculate the allocation torque, a distributed optimization algorithm is developed. The proposed method can provide each nanosatellite with the optimal torque through communication with its neighbors, leading to energy consumption balance. The communication load is reduced using an event-triggering detector without Zeno Effect. Compared with the other two methods, the effectiveness of the proposed method is demonstrated using attitude maneuver examples. PubDate: 2024-07-17
- Spacecraft Anti-reconnaissance Game based on Particle Swarm Optimization
Algorithm-
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Abstract: Abstract This paper proposes an optimization strategy using competitive particle swarm algorithm for the anti-reconnaissance problem in the near-range game scenario of spacecraft. Firstly, the constraint analysis is carried out for the anti-reconnaissance game scenario, and game model are designed. Then, an adaptive sliding mode pointing controller is designed, and the effectiveness of the controller is verified through simulation examples. For the survival game, the two-point boundary value problem is derived. To facilitate the solution, it is further transformed into a single-objective optimization problem, and solved by using competitive particle swarm optimization algorithm. The simulation results verify the effectiveness of the solution method. PubDate: 2024-07-11
- Research on strategies of multi-spacecraft interception based on matrix
game-
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Abstract: Abstract Aiming at the problem of non-cooperative spacecraft interception under the many-to-many pursuit-evasion game scenario with complete information, this paper establishes a multi-round interception model based on the theory of matrix game, and elaborates the practical significance of the Nash equilibrium mixed strategy in this scenario. Aiming at the demand of model solving, a model solver based on genetic algorithm is designed. Finally, the optimized strategies for many-to-many space interception game is analyzed based on the given scenario and control requirements, and the effectiveness of the established model and its solver is verified by numerical simulation. PubDate: 2024-07-01
- Scientific Objectives and Suggestions on Landing Site Selection of Manned
Lunar Exploration Engineering-
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Abstract: Abstract Focusing on cutting-edge scientific issues related to lunar exploration and applications, 9 overarching goals and 38 specific objectives for China's manned lunar exploration program have been proposed. Leveraging China's technical capabilities in manned spaceflight and lunar exploration, as well as its expertise in lunar and planetary science, the objectives center on scientific research, lunar-based scientific research, and resource exploration and utilization. Based on these scientific goals and trends in domestic and international manned lunar exploration landing site selection, China's basic principles and processes for selecting landing sites have been established. Thirty prime landing sites have been identified, including 11 low-latitude regions and 1 mid-latitude region, taking into account scientific value and engineering implementation conditions. These scientific objectives and landing site selection recommendations will serve as important guidance and top-level input for the design and implementation of China's manned lunar exploration program. PubDate: 2024-06-27
- Research on Reusable Technology System for New-Generation Manned
Spaceships-
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Abstract: Abstract Aiming at the main constraint of high cost of round-trip transportation between Earth and space in the large-scale space application of space station and manned deep space exploration program, in the development of new-generation manned spaceships in China, to reduce the operation cost and enhance the economic benefit, the relevant design is carried out in accordance with the reusable capability. First, the concept of reusable mode of new-generation manned spacecraft is put forward, the technical difficulties of reusable spacecraft are analyzed, and the technical ways to solve the problems are given in four dimensions, design of reusable conditions, design of reusable performance, design of reusable maintenance security, and design of autonomous health detection and diagnosis, so as to form the technical system of reusable new-generation manned spacecraft. This study has clarified the reusable technology route and realization direction of the new generation of manned spacecraft, which can be used to guide the development of future reusable spacecraft and lay the foundation for large-scale space development. PubDate: 2024-06-04 DOI: 10.1007/s42423-024-00157-z
- Residual Carrying Capacity Evaluation and Parking Orbit Replanning for
Lunar Exploration Launch Vehicle-
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Abstract: Abstract To cope with the potential thrust-drop malfunction of the manned lunar exploration launch vehicle, a parking orbit replanning method is proposed based on the evaluation of the residual carrying capacity of the launcher. By analyzing the constraints of the whole flight profile and the characteristics of the Earth–Moon transfer orbit systematically, the offline trajectory planning algorithm exhibits improved convergence performance, and thus can be used to evaluate the residual carrying capacity as thrust-drop happens. For the situations that the launcher is not capable of injecting the transfer orbit, a sequential orbit/trajectory replanning method is designed to guarantee the safety of the astronauts. On the premise of ensuring the altitude of the parking orbit, the elements about the orbital plane are further optimized to provide a favorable initial state for the subsequent rescue action. Meanwhile, the nonlinearity of the terminal constraints is alleviated by the injection point forecast, and the initial reference is generated by convex optimization method with well convergence; thus, the solving efficiency of the sequential replanning algorithm can be improved. Simulation results show the proposed method can generate the trajectory that transport the spacecraft to the optimal parking orbit under the thrust-drop malfunction situation. This is an English translated version of “Residual Carrying Capacity Evaluation and Parking Orbit Re-planning for Lunar Exploration Launch Vehicle”. PubDate: 2024-05-14 DOI: 10.1007/s42423-024-00154-2
- Perspectives on China’s Manned Lunar Scientific Research and Test
Station-
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Abstract: Abstract China's lunar exploration efforts have been focused on developments in space that are sustainable. To this end, the country plans to construct a manned lunar scientific research station after successfully landing on the Moon, with the aim of ensuring long-term human survival on the lunar surface and developing and utilizing lunar resources. To achieve this goal, extensive research has been conducted on the development plans and current situation of manned lunar exploration. Based on the development law of human deep-space exploration, a goal of verifying human long-term, extraterrestrial survival technology and addressing challenges, while carrying out in-depth scientific research on the Moon and exploring its resources, is proposed. After analyzing the difficulties and development trends of the station's construction, possible incremental development plans and paths for the future are discussed. Considering the four major elements of strategy, science, engineering, and economics, and focusing on the safety requirements of manned spaceflight, a preliminary idea for selecting the station location is proposed. Finally, six key technologies and challenges are analyzed with the development plan. Overall, China's commitment to lunar exploration reflects its dedication to advancing scientific knowledge and technological capabilities, while also contributing to the long-term sustainability of human presence in space. PubDate: 2024-05-07 DOI: 10.1007/s42423-024-00155-1
- Research on Integrated Mission Planning and Design Method for
China’s Manned Lunar Exploration-
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Abstract: Abstract Aiming at the requirements of top-level mission planning for manned lunar exploration, an integrated mission planning and design method is proposed for China’s manned lunar exploration. By decomposing the whole flight profile, an integrated method based on the circumlunar perturbation is proposed. Then, the three key constraints of sunlight condition, lunar orbit and return landing sites are identified and analyzed. According to the analysis results and the different time scale constraints, the mission monthly window, daily window and hourly window are gradually selected to meet the engineering requirements. In the end, the method has been verified by the co-simulation of manned lunar exploration on the integration platform. It has been proved that the proposed method can solve the comprehensive window design problem for standard and delayed mission, and also provides an effective pathway for rapid planning in a large time scale. This is an English translated version of “Research on Integrated Mission Planning and Design Method for China’s Manned Lunar Exploration” originally published in Journal of Astronautics. PubDate: 2024-05-06 DOI: 10.1007/s42423-024-00156-0
- System Technology for Improving the Performance of Manned Lunar
Exploration-
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Abstract: Abstract Manned lunar exploration missions require thousands of tons of launch vehicles to deliver astronauts and a small number of payloads to the lunar surface. To improve the system performance of manned lunar exploration missions, an analysis is conducted at the system level, including the design concepts, design methods, model optimization, and data correction. The proposed technologies include probability-based systems design, integrated design of spacecraft and launch vehicle, optimization design based on digital models, and system performance improvement based on measured data correction. Based on the practice of the systems design of manned lunar exploration missions, the application effects of these technologies are summarized, and the direction for future research is pointed out. These technologies play an important role in improving the system performance of manned lunar exploration and maximizing the efficiency. PubDate: 2024-04-07 DOI: 10.1007/s42423-024-00152-4
- Numerical Investigation on Supersonic Airflow Around Tangent Ogive Wedge
of Varying Fineness Ratio-
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Abstract: Abstract The purpose of this study is to report the numerical investigation on the aerodynamic performance of tangent ogive wedge of varying fineness ratio from 2 to 4 when fully submerged in an incoming supersonic airflow having a velocity of Mach 2.5 and at zero degrees angle of attack. Numerical simulations have been carried out for flow over tangent ogive wedge using ANSYS CFD. A computation domain was created with appropriate geometrical constraints and was meshed into elements of optimum size. The supersonic airflow was simulated to observe and analyze the effects of change in fineness ratio of tangent ogive wedge on various aerodynamic parameters of interest under given boundary conditions and flow physics. It was observed that tangent ogive wedge with increasing fineness ratio experienced decreasing pressure drag force. The nature of shock generated for various tangent ogive wedge has been compared to understand airflow/shock interactions. The presented study revealed the dependency of different aerodynamic parameters on the fineness ratio of tangent ogive wedge, which may be efficiently utilized in missiles, rockets, and bullet design. The reported findings would contribute towards optimizing tangent ogive wedge shapes for supersonic missiles, rockets, and bullets, delivering optimum aerodynamic performance under given operating conditions. PubDate: 2024-04-02 DOI: 10.1007/s42423-024-00151-5
- Crawling Robot Path Planning on the Surface of the CubeSat
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Abstract: Abstract To prolong the service life of satellites, space crawling robots are used for in-orbit services such as inspection and repair. However, the complex structure of the satellite surface requires path planning. Most current path planning algorithms are only applicable to the planar and 3D unconstrained case, and cannot be applied to CubeSat surface with abrupt changes in normal vectors. In this paper, we design a cube unfolding method to reduce the cube surface path planning problem to a planar path planning problem. This is accomplished by obtaining obstacle point cloud data through laser radar and converting the point cloud data into a grid map using the Gmapping algorithm. And considering the limitation of arithmetic power for operations on satellites, this paper uses PSO to solve this planar path planning problem. The experimental results show that the method can be applied to the surface of the CubeSat. PubDate: 2024-02-15 DOI: 10.1007/s42423-024-00149-z
- AI and Robots Impact on Space Exploration
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Abstract: Abstract Artificial intelligence (AI) has changed how humans live on Earth. What lies beyond our planet' How can knowledge advance the work and the scope of the search' AI plays a crucial role in space exploration and travel by assisting crews and ground operations. It facilitates activities like analysing cosmic occurrences, operating machinery, charting stars and black holes, and other activities that people are unable to carry out in space. AI is used by several organisations to discover and advance life for all astronauts. Scientists and governments from all over the world have long been fascinated by space travel, because it contains the key to understanding human history and many cosmological hypotheses, including the potential of extra-terrestrial life. The region of space that we can view via a telescope is known as the visible world. However, researchers and scientists think that the cosmos may be far larger. A large part (around 96%) of the space is unused. PubDate: 2024-02-01 DOI: 10.1007/s42423-023-00147-7
- Error Compensation of a Low-Cost Analogue Sun Sensor for
Micro-/Nano-satellites-
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Abstract: Abstract The growth of micro-/nano-satellites requires miniaturized sun sensors which could be applied in the Attitude Determination and Control System easily, conveniently and cheaply. In this work, the error compensation methods of a low-cost Analogue Sun Sensor, COSSA, have been innovatively proposed, which mainly includes two error compensation mathematical models and related testing and calibration methods. From theory and engineering perspectives, Error Source Propagation Model and Linear Surface Fitting Model have been built, respectively; then zero-point calibration method and surface fitting calibration method have been illustrated to compensate the measurement error. After testing and calibration experiment, the accuracy of COSSA prototype is better than \(0.25^\circ \) (1 \(\sigma \) ), which is 2 \(\sim \) 4 times higher in accuracy compared with most analogue sun sensors. Therefore, the feasibility and effectiveness of error compensation methods could be well-proved. PubDate: 2023-12-22 DOI: 10.1007/s42423-023-00142-y
- Infant Milk Powder After Ī³-Irradiation and Accelerated Storage as an
Indicator for Space Food Stability-
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Abstract: Abstract At present, terrestrial food sources are used to provision astronauts for engaged in space missions confined to low Earth orbit. However, in the future, long-duration space exploration is planned for the Moon, and, beyond that, to Mars. Food for such extended missions needs a shelf-life of up to 5 years, a sustained nutritional and product quality. Space radiation can impact on such food, but little is known of what impact this could have on these materials. In this study, we evaluated the impact of radiation dosage and accelerated storage on infant milk powder (a formulated product consisting of proteins, fat, lactose, vitamins, and minerals), to evaluate its potential as an indicator for (chemical) space food stability. The milk powder was irradiated at different dosages (0, 2, 10, and 50 kGy) and underwent different storage conditions (20 or 50 °C for 0, 14, 28, 56, and 77 days), with subsequent color measurement and chemical analysis. It was found that γ irradiation had an impact on the milk powder’s color. It was speculated that this change was related to the Maillard reaction. Some changes were also found with the chemical composition, particularly, vitamins A and C, unexpectedly due to their susceptibility to radiation. Notable differences were not observed though for other components (vitamins, fatty acids, and amino acids). We conclude that infant milk powder shows great promise as an indicator of the impact of γ radiation, and accelerated storage, for (chemical) space food stability. PubDate: 2023-12-08 DOI: 10.1007/s42423-023-00140-0
- SustainableĀ Assemblage of Clustered Wastages and Meticulous Exertion of
Disposal System: A Comprehensive Review-
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Abstract: Abstract Widespread vegetable wastage in Indian markets is a pressing issue, driven by factors like inadequate storage, inefficient transport, improper handling, and a lack of standardized packaging and grading. This wastage results in substantial economic losses for farmers and traders and adverse environmental effects, including increased landfill waste, greenhouse gas emissions, and pollution. Moreover, rotting vegetables in markets pose health risks and compromise food safety. To combat this problem, a comprehensive research study has been conducted, employing a mixed-method approach. This research combines quantitative and qualitative methods, including a questionnaire survey of 100 residents, structured surveys, and in-depth interviews with relevant stakeholders. The study investigates the causes and consequences of vegetable wastage in Indian markets, with a particular focus on its environmental and public health impact. The research also proposes a systematic waste management procedure to address these issues and mitigate potential drawbacks. By uncovering the root causes, assessing the effects, and offering practical solutions, this study aims to contribute to a sustainable and efficient waste management system in Indian vegetable markets. The findings and recommendations in this research serve as a foundation for policymakers, market authorities, farmers, and other stakeholders to develop effective strategies and policies for waste reduction and management in vegetable markets. PubDate: 2023-12-02 DOI: 10.1007/s42423-023-00141-z
- Application of CubeSat Technologies for Research and Exploration on the
Lunar Surface-
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Abstract: Abstract In view of ESA’s horizon goal of establishing a human presence on the Moon by 2040, the Earth’s moon is increasingly coming into the focus of research and industry. Lunar exploration can benefit from systems developed for low-Earth orbit, as the environmental conditions are overlapping. The development of the CubeSat industry in recent decades has led to a revolution in access to near-Earth space. The goal of Neurospace and its partners is to explore the similarities of both environments for a direct application of existing CubeSat technologies for lunar exploration. Using an open standard and a tiered approach for the development of lunar rovers will allow future missions to focus more on the actual use case rather than the individual development, qualification, and certification of required components. This paper introduces the HiveR rover and provides a classification of the future importance of robotic systems for lunar exploration. It also discusses, in review of past lunar missions, how such rovers differ from previous lunar rovers, and how important they can be in supporting increasingly complex missions. The similarities and differences between the low-Earth orbit and the lunar surface are outlined. Based on this, the new challenges in adapting existing CubeSat technologies for robotics on the lunar surface will be discussed and initial solutions presented. As examples of potential payloads, various experiments are presented, such as a robot arm that was developed to fit in a 1 U volume. It can be used for docking operations between individual systems or various tool handling operations. PubDate: 2023-12-01 DOI: 10.1007/s42423-023-00144-w
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