Advances in Astronautics Science and Technology最新文献

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.

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.

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.

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.

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.

Cyclically asymmetrically distributed charges introduced to explain a cause of gravity produce significant directed forces for useful safe energy generation, as harnessed by the Electric Kinetic Pulse generator, an experiment to illustrate cyclically asymmetrically distributed charges. This is established by analysing solutions to the equations of motion and energy of 4 charges in the Electric Kinetic Pulse generator, as they alternately move close to and from electric field singularities using repulsion in each of the 4 cylinders; with extensions to several charges. The system is shown to be robust against transverse vibrations. The theoretical validity of the generator and the principles underlying cyclically asymmetrical charge distributions is established. The theoretical verification proposes an iterative process for solving first order differential equations which requires continuity but no separation of variables. Ample useful nuclear energy independent of heat phenomena or the atmosphere can be generated with no harmful radiation or radioactive waste.

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.

Integrating the artificial intelligence into space missions is attracting increasing attention from scholars. This paper concerns on the optimal guidance problem of orbital pursuit-evasion games, and an optimization method based on the deep neural network (DNN) is proposed to improve the efficiency of solution. First, the problem is formulated by a zero-sum differential game model, which transforms the original problem to a TPBVP. Second, we propose an optimization method using a DNN to generate individual guesses for further optimization through a gradient-based local optimization algorithm. Finally, numerical simulation results show that, after training the DNN with samples generated through the traditional method, the proposed optimization method statistically improves the efficiency over the traditional optimization by roughly two orders of magnitude without losing quality, and it is feasible in different cases.

The present study numerically investigates the shock-wave/boundary-layer interactions (SWBLIs) inside a scramjet intake at Mach 4.03. A 2D-planar and an axisymmetric intake are investigated using commercial code ANSYS-Fluent. The density gradient for intakes is computed to investigate and compare the shock cell structure and the separation bubble size. Besides, the velocity and pressure distributions are analyzed for planar and axisymmetric intakes. It is observed from the wall pressure data that the shock strength in the case of axisymmetric intake is lesser than the planar intake. Also, the interaction region in the axisymmetric intake is shifted further downstream with a progressive decrease in shock angle. The recirculation zone or the separation bubble size is minimal for the axisymmetric intake than for planar intake, resulting in higher effective mass flow into the combustion chamber. It can be observed that although the cowl surface experiences the maximum wall static pressure, the recirculation zone formed over the cowl surface is comparatively smaller than that of the ramp surface. The normalized total pressures at the isolator exit indicate that the axisymmetric intake is more efficient in conserving the flow energy than the planar intake. The temperature rise over the ramp surface is higher for planar intake; however, the temperature fluctuations over the ramp surface are more for axisymmetric intake.