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Communication-navigation Integration Based on Satellite Communication and its Application in Lunar Exploration
XIE Haoran, ZHAN Yafeng, WANG Xiaowei, CHEN Xi
Satellite communication-navigation integrated technology allows users to achieve communication and navigation at the same time. Compared with an autarkical and independent satellite communication or satellite navigation system, a communication-navigation integrated system is more comprehensive. At present, BeiDou Navigation Satellite System can provide radio navigation service and radio data service; most satellite in the world can also measure the distance between satellite and ground station during communicating, even provide time base for satellite. However, there is still a long way to go from these existing practices to the ideal integrated communication and navigation system. Based on satellite communication, a new integrated communication-navigation architecture was proposed, and a case of using the lunar relay communication system to achieve lunar navigation in the setting of manned lunar exploration was given. The simulation results show that the proposed communication and navigation integrated system can provide satisfactory positioning and timing precision, besides communication, for the users on the lunar surface.
Fast Mission Plan Repair Method for Mars Rover Based on State Difference
CHEN Chao, XU Rui, LI Zhaoyu
The uncertainty of Mars environment and the difficulty to predict the failure of electronic equipment will seriously affect the actual effect of the pre-designed plan of the rover on Martian surface, resulting in plan execution failure. To solve this problem, a fast mission plan repair method based on state difference is proposed under the fact that there is long delay between the Mars rover and the ground station. This method constructs partial states at different times by extracting the key information from the existing plan, lying on the difference between the perception state and the necessary state of action execution. And then the rapid mission plan repair strategy for Mars rover based on the partial state is presented. In this strategy, to improve the efficiency of plan repair, the search space deletion method based on the state difference between the actual state and the partial state is proposed. Simulation results demonstrate that this method can not only improve the efficiency of mission plan repair, but also ensure the plan stability.
High Specific Energy Design of Power Supply and Distribution System for Chang'e-5 Orbiter
LIU Zhiqiang, ZHAO Chen, CAO Yan, CHEN Jianyue, YANG Min, LI Tianyi
Due to the launch capability of launch vehicle, the deep space probe has an urgent need to reduce its own weight. Based on the most advanced space power supply technology in China, the power supply and distribution system of Chang'e-5 orbiter adopts ultra-high energy density solar cells and batteries, and invents a new bus topology. Through a series of lightweight power distribution system design, the power to weight ratio of the whole probe reaches the domestic leading level. The power supply and distribution system of spacecraft has passed the ground verification and flight test on orbit, which can provide reference for the follow-up research and design of high specific energy of power supply and distribution system of spacecraft.
Research Advance in Lunar Space Enviornment
WANG Mingyuan, WANG Mei, PING Jinsong, HAN Songtao
 doi: 15982/j.issn.2096-9287.2021.20200013
After more than fifty years lunar exploration, our understanding of the lunar space environment is still short. The information of lunar dusty exosphere was given by ARTEMIS mission and the lunar atmosphere and dust environment detector which were developed by NASA. Based on the radio experiments of several lunar missions, the existence of lunar ionosphere is proofed. The current status and observation of lunar exosphere and ionosphere are introduced in this paper. With the help of the low frequency radio astronomical payloads carried by chang'e-4 relay satellite and the lander, more information of lunar space environment will be detected.
Autonomous Relative Navigation Based on Sequential Image Measurements of Unknown Landmarks
XU Chao, HUANG Xiangyu, LI Maodeng
An autonomous relative navigation method based on sequential image measurements of unknown landmarks for planetary landing in unknown environment is presented in this paper. The proposed method uses line-of-sight vectors of landmarks with unknown 3D positions tracked in three sequence images and position information derived from inertial measurement unit at the time instances of the three images to develop implicit measurement constraints. An implicit extended Kalman filter tightly integrates the constraints with the measurements from IMU to estimate the lander's position and velocity relative to the landing site. Numerical simulations of Mars landing indicates the proposed navigation method is efficient and satisfies the relative navigation requirement of safe planetary landing.
Central Difference Convexification Method for Soft-landing Trajectory Optimization in Planetary Powered Descending Phase
LI Mingxiang, PAN Banfeng
Aiming at the mission of real-time online guidance for fixed-point soft landing on planet, this paper designs an algorithm based on sequential convex optimization to solve the fuel-optimal trajectory. The pre-labeled central difference algorithm is used to linearize the dynamics equations and the termination condition based on the deviation of index is proposed to judge whether it converges, which can generate a fuel-optimal trajectory quickly. Besides, a fitting function is given to approximately estimate the optimal terminal time by analysing the relationship between the terminal time of optimal trajectories and their remaining fuel, which can reduce the amount of unknown variables. The numeric simulation results of this algorithm show the weak sensitivity to initial guess, good convergence and small terminal error compared to the traditional convexification method of linearizing the dynamics equations whose variables are substituted at first.r.
Advances in Space VLF Type II Solar Radio Bursts
GAO Guannan, WANG Min, DONG Liang, GUO Shaojie
 doi: 10.15982/j.issn.2096-9287.2020.20190222001
Solar flares and coronal mass ejections(CMEs)are the source disturbances of space weather. The type II solar radio burst is the result of electromagnetic radiation caused by CME driven shock moving in corona and interplanetary space. Based on the study of solar physics and space weather forecast, the spectrum characteristics and physical causes of type II radio burst, especially VLF type II solar radio burst, are analyzed, it shows that VLF type II solar radio burst can not only be used to estimate the velocity of CME shock, diagnose the coronal magnetic field, but also provide reference for space weather forecast. The research results can provide useful reference for the scientific research of space VLF radio observation equipment.
Adaptive Control for Space Greenhouse Light Assembly
Yu. Berkovich, A. Buryak, O. Ochkov, O. Perevedentsev, S. Smolyanina
 doi: 10.15982/j.issn.2096-9287.2020.20191108001
To date, Light Emitting Diodes-based (LED) illuminators are widely used for plants lighting in greenhouses in addition to natural light, as well as in plant factories without natural light. Optimization of artificial lighting parameters, such as the daily light integral and the ratios of different spectral components, can significantly reduce the cost of crop production in light culture including Space Greenhouses (SG) in Biological Life Support Systems (BLSS). However, the optimization of LED lighting systems is so far limited by the lack of information about the physiological effects caused by narrow-band radiation, as well as the complexity of the mathematical description of plant crops reactions to the changes of LED lighting parameters. In conditions of artificial illumination, crop producers usually strive to establish an optimal light regime that is constant throughout the whole growing season. However, there is experimental data on changes in the requirements for the illumination regime of crops with increasing age of plants. A promising approach to improving the parameters of crops LED lighting is the adaptive method of search engine optimization using biological feedback. The Adaptive Lighting System (ALS) is described on the basis of illuminator with red and white LEDs built at the Institute for Biomedical Problems (Moscow, Russia) for Chinese cabbage cultivation. The adaptive control procedure implements a continuous automatic search for current lighting parameters that provide optimal plant growth characteristics in real time. ALS includes a closed growth chamber with Light Assembly (LA) based on red and white LEDs, equipped with a Gas CO2 Analyzer (GA). The Photosynthetic Photon Flux Density (PPFD) from each type of LEDs can be controlled independently from each other according to the program in the MicroProcessor (MP). Periodically, infrared GA measures the decrease in CO2 concentration inside the growth chamber caused by Visible Photosynthesis (VF) of the crop. MP receives a signal from the GA output and calculates the photosynthesis rate of the crop, as well as the value of the lighting quality functional at the current time. Then the program compares the obtained values of the optimization criterion at the current moment and at the previous step and calculates the direction of the gradient according to picked algorithm and the new values of the LED supply currents, leading to a change in the value of the optimization criterion in the right direction. Further, the power supply unit realizes the currents of LED chains of each type and LA changes the plant lighting mode. As a criterion for the lighting quality in SG we used the minimum specific value of the Equivalent System Mass (ESM), which depends on the plants lighting regime. The cost coefficients of the unit of SG planting area equivalent mass and the unit of electric power consumed by SG significantly depend both on the spacecraft design and on the space expedition scenario. According to the literature, the equivalent system mass estimates depending on the light flux density and the crop light efficiency have been calculated in a spacecraft for the space expedition scenario at a long-term use lunar base with a crew of 4. To search for the current optimal lighting parameters during the plant growth, gradient and simplex algorithms were used. As optimization factors, the integral PPFD incident on the crop at the shoot tips level and the ratio of red and white light flux densities (factors X1 and X2, respectively) were used. Factor X1 was regulated in the range from 200 μmol/(m2·s) to 700 μmol/(m2·s), and factor X2 was from 0 to 1.5. The effectiveness of ALS was evaluated by comparing ESM when using ALS or the best constant LED lighting from comparison experiment. Adaptive optimization of Chinese cabbage crop lighting from the 14th to 24th day of vegetation according to the minimum ESM criterion (1) for the lunar base expedition led to a 14.9% saving in the SG equivalent mass. Similar systems with other optimization criterion can be use for terrestrial plant factories.
Articles just accepted have been peer-reviewed and accepted, which are not yet assigned to volumes /issues, but are citable by Digital Object Identifier (DOI).
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2021 Vol.8 No.1 Content
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Topic:The technology of new generation medium-lift launch vehicle (Guest Editor:Professor SONG Zhengyu,China Academy of Launch Technology)
LM-8: the Pioneer of Long March Rocket Series on the Innovations of Commercialization and Intelligence
SONG Zhengyu, WU Yitian, XU Shanshu, CHEN Xiaofei, XIAO Yun
2021, 8(1): 3-16.   doi: 10.15982/j.issn.2096-9287.2021.20200009
Abstract(909) HTML(263) PDF 1771KB(257)
The latest innovations of the Long March 8 (LM-8) launch vehicle is reviewed. The LM-8 launcher fully inherits the achievements of Chinese in-service rockets and the new generation rockets, and focuses on launching satellites to the sun-synchronous orbit (700-1 000 km), taking into account the launch services for LEO and GTO satellites. The LM-8 launcher is available in both combinatorial and integrative configurations for a variety of missions. In order to enhance market competitiveness, a series of innovative practices have been taken, including agile manufacturing, system integration, responsive launch, autonomous and unattended operation, and simplified launch site infrastructure. In response to the future trend of intelligent rockets, the autonomous technologies are explored for LM-8, such as onboard dynamic trajectory planning, active control of take-off drift, and automated launch window correction. It also paves the way for reusable launcher in steps, conducts the demonstration for vertical landing with side and core boosters strapped together, and makes progresses in large-scale light landing mechanism, autonomous guidance method, etc. These innovations eventually build the LM-8 into a new generation of medium rocket with high cost-effective performance, good usability, and high reliability and safety.
Integrated Design Technology of Electrical System for the Long March 8 Launch Vehicle
ZHOU Tao, XU Yang, HU Haifeng, ZHANG Siyan, ZHANG Huanxin
2021, 8(1): 17-26.   doi: 10.15982/j.issn.2096-9287.2021.20200014
Abstract(155) HTML(37) PDF 809KB(78)
Integrated design is the main development trend of the spacecraft electrical system. The development status of electrical system in the new generation launch vehicle at home and abroad is reviewed, and the integrated architecture of electrical system based on the redundant system bus and integrated electronic architecture is put forward for the new generation medium Long March 8 (CZ-8) launch vehicle. The integrated design technology of electrical system is introduced from the aspects of system integration, power supply integration, software integration, test integration and telemetry integration. The integrated design technology will be used for the integration of system functions, and also for the breakthrough of the electrical system from traditional sub-system development to cross-system integration. Therefore, the integrated design technology of the electrical system can be used to simplify the test launch process and improve the launch capability, meeting the needs of a new generation of medium launch vehicles with low cost, high reliability, and fast launch.
A Self-locking Electro-mechanical Actuation System for Liquid-Propellant Rocket Engine
JIANG Yang, LAN Tian, ZHENG Qijia, WANG Zhihui, ZHAO Yingxin
2021, 8(1): 27-33.   doi: 10.15982/j.issn.2096-9287.2021.20200006
Abstract(175) HTML(35) PDF 1067KB(41)
A self-locking electromechanical actuation system to gimbal a high thrust liquid rocket engine is put forward to meet the demands of the batch production and the triplex horizontal preparation for an agile launching of China’s new generation launch vehicles. A self-locking module is designed, a tandem compact electro-mechanical actuator and a control algorithm to suppress structural resonance are adopted. Ground experiments are carried out. It is shown that, the requirements of a long term horizontal transportation, a horizontal testing to tolerate the engine gravity effect, the control of the low frequency resonance of a liquid engine, and easiness for batch production, shall all be satisfied, laying a good foundation to facilitate the development of the next generation medium-sized launch vehicle in China.
Digital Manufacturing Technology of Special-shaped Pipe of Launch Vehicle Based on Point Cloud Measurement
WEI Qiang, LIU Fengcai, SU Zaiwei, LIN Yanlong
2021, 8(1): 34-41.   doi: 10.15982/j.issn.2096-9287.2021.20200011
Abstract(119) HTML(23) PDF 942KB(27)
In view of the current manufacturing model of launch vehicle pipe sampling and final assembly, it severely restricts the assembly period of the launch vehicle. In this paper, the use of laser scanning method is proposed to build a physical point cloud model of different arrow body. According to the assemble benchmarks based on different rocket body, the data is extracted from the physical point cloud models of different rocket body to establish the datum plane and datum circle center, using benchmark alignment to realize digital assembly of point cloud models of different arrow body, and using coarse matching, fine matching and other algorithms to analyze the benchmark establishment and benchmark alignment. Based on the assembled point cloud model, according to the "point, line, surface" way to establish the catheter model for subsequent processing. The digital pre-manufacture of the carrier rocket sampling catheter is realized sucessfully.
Propellant Flow Characteristics in Tank and Related Impact Analysis During the Vertical Landing Stage
GA Yongjing, WANG Haosu, ZHANG Qingsong, XU Shanshu, WU Yitian
2021, 8(1): 42-50.   doi: 10.15982/j.issn.2096-9287.2021.20200012
Abstract(155) HTML(38) PDF 1816KB(50)
Reusable technology is one of the key factors to realize the launch vehicle reusability. It is a hot spot in current research to achieve the sub-stage reusability by vertical landing. During the process of launch vehicle taking-off and vertical landing, the propulsion system is not only required to provide thrust in the ascent, but also to realize the smooth deceleration and control of vertical landing. It is required that the rocket engine shall be improved to possess multiple-start and in-depth thrust regulating capability and also have higher requirements to propellant management. During the vertical landing process, the propellant flow characteristics in tank are greatly affected by the acceleration of the vehicle. If there are some lateral disturbance, the propellant in the tank will move violently due to severe acceleration decrease and may affect the normal operation of the rocket engine. In this paper, the propellant flow behavior during the vertical landing process is investigated with Flow 3D numerical simulation, and the influence of the lateral and axial acceleration on the propellant flow behavior during the engine shutdown process is analyzed. The results show that the sloshing amplitude of the propellant is related to the amplitude of the lateral disturbance when the axial acceleration changes to a certain extent, and the sloshing amplitude of the propellant will be greatly enlarged when axial forces suddenly decrease. It is suggested that in the process of vertical taking-off and landing, the attitude of vehicle should be guaranteed as much as possible to avoid large lateral disturbance.
Research on Design and Process Program for Grid Fin of Reusable Rocket
WANG Chen, ZHANG Hongjian, YAN Wei, ZHANG Xi, SHI Yuhong, GUO Yue, YUAN Han
2021, 8(1): 51-61.   doi: 10.15982/j.issn.2096-9287.2021.20200018
Abstract(110) HTML(39) PDF 1137KB(47)
Grid fin aerodynamic control mechanism is one of the reusable rocket’s key parts. The design and manufacturing of grid fin is rather complex that coupling multi-specialty and multi-link. Aimed at the requirements of the reusable rocket, key design parameters of grid fins and their influences are presented combined with the grid fin’s geometric features from the aspects of working principle, geometric features, section shape, forward and backward sweep, etc.. Considering the thin-wall complex features of lattice and the requirements of high temperature resistance, several kinds of technological schemes and process program of titanium alloy forming and composite molding which can be used in the manufacturing of grid rudder are studied. From the aspects of design difficulty, process difficulty, product qualification rate, product accuracy and cost constrains, a comparative analysis of the process programs are made. Finally, the principles of grid fin design are proposed, providing a reference for the design of the Long March-8R(CZ-8R) rocket and other reused rockets.
Research on Launch Vehicle Reliability Assessment of Small Sample Based on Bayes Theory
SONG Zhengyu, FANG Zhigeng, HE Wule, SUN Yunke, WANG Zhao, LI Caixia, LIU Sifeng
2021, 8(1): 62-69.   doi: 10.15982/j.issn.2096-9287.2021.20200005
Abstract(137) HTML(51) PDF 530KB(36)
Aiming at the advanced technology, high development cost and difficult implementation of reliability appraisal test of LM-8 launch vehicle, a method of reliability assessment of small sample based on Bayesian theory is proposed. According to Bayes theorem, various pre-test information is fully utilized to make up for the deficiency of experimental data. Taking Weibull life model, Exponential life model and Binomial life model as three examples of life different distribution types, corresponding mathematical model and numerical calculation method combining Bayesian theory are discussed. Finally, three different types of equipment in the launch vehicle system are selected for reliability evaluation and the results show that the proposed method can make full use of existing information, of which assessment results are superior to the classical method.
Low-cost and Fast Manufacturing Technology for Commercial Liquid Rocket Structure
YANG Ruisheng, CHEN Youwei, WANG Jingchao, CONG Yan
2021, 8(1): 70-79.   doi: 10.15982/j.issn.2096-9287.2021.20200008
Abstract(158) HTML(32) PDF 740KB(49)
With the gradual opening up and rapid development of the space launch application market, commercialization is an inevitable trend of the development of the launch vehicle. The rocket structure system is complex and involves a lot of manufacturing technology, which is an important factor restricting the production efficiency and cost of the rocket. How to realize the low cost and fast manufacturing of the rocket body structure has become an important research direction in the development of commercial aerospace. In this context, the application of manufacturing technology of key structural parts of liquid launch vehicle rocket body is systematically summarized, and the development direction of the commercial vehicle structure system is proposed, combined with the development of the LM-8 launch vehicle. The application of low cost and quick manufacturing technology of rocket structure is explored based on the integration of design and process, effectively improving the structure of the arrow product quality and production efficiency.
Introduction of Space Exploration Progress for Planetary Radio Burst Emission
PING Jinsong, WANG Mingyuan, ZHANG Mo, CHEN Linjie, DONG Liang, WU Yuxiang
2021, 8(1): 80-91.   doi: 10.15982/j.issn.2096-9287.2021.20200016
Abstract(117) HTML(34) PDF 810KB(26)
At low frequency electron-magnetic wave band, planetary bodies not only emit thermal radiation, but also emit non-thermal radiation burst. The typical emission is planetary auroral radio burst consists of planetary kilometric wave burst, Jovian radiation at hectometer and decameter wavelengths. This kind of burst has been observed on the ground and in the space for dozens of years. The developed method can also be used as remote sensing tool to detect the inner structure of Jovian magnetosphere. However, the characteristics and mechanism have not been fully understood for the solar system planetary radio burst, there are still quite a lot of open questions left. Similar radio burst may also be observed from the exoplanetary systems. Following the development of space technology, radio astronomical observation has extended to kilometer wave. In the future the large radio array at low frequency can play key role to uncover the mechanism for the planetary radio burst, and also can be used to detect the exoplanets. The Chang’e-4 lunar mission with its low frequency payloads is working as pathfinder for the Earth Auroral Kilometer Radiation (AKR) and Jovian bursts,
Research Advances of Solar Radio Type Ⅲ Bursts at Space Very Low Frequencies
TAN Baolin, TAN Chengming, HUANG Jing, CHEN Linjie
2021, 8(1): 92-99.   doi: 10.15982/j.issn.2096-9287.2021.20190227002
Abstract(140) HTML(33) PDF 761KB(20)
Solar non-thermal high-energy particle flows are one of the main triggering sources of the disastrous space weather events. Their main observational manifestation is radio Type Ⅲ bursts with fast frequency drifting rate. This work introduces the main advances of observational instruments and scientific researches on the solar radio Type Ⅲ bursts at the space very low frequency (< 30 MHz SVLF) in the world, including the space-based or lunar-based solar SVLF spectral polarimeters with high temporal and spectral resolutions. We also discuss carefully the existing problems on the solar radio observations and related researches, also including the main scientific aims and prospective of the space-based or lunar-based solar SVLF observations.
Study of Very Low Frequency Solar Radio Emission Detection with Space Vector Antenna
CHEN Linjie, YAN Yihua, TAN Baolin
2021, 8(1): 100-108.   doi: 10.15982/j.issn.2096-9287.2021.20190411002
Abstract(343) HTML(124) PDF 1436KB(35)
Solar winds, Coronal Mass Ejections(CME), interplanetary shock waves and high-energy particle events, induced by the solar radio bursts, are called as solar electromagnetic storms. The propagation, acceleration, and evolution of the CMEs, solar winds, interplanetary shock waves and high-energy particle phenomena mainly happen at the frequency range from tens of kHz to tens of MHz, which is generally considered as the frequency band of Very Low Frequency(VLF). Though, there are already few space instruments that have investigated the VLF solar radio emissions, most of the observations are spectral measurements, and only occupied part of the whole VLF band, while the imaging observations of the VLF solar radio bursts are still blank. Based on the characteristics of the vector antenna, it can estimate the Direction Of Arrival(DOA)of the incoming waves, which can be used to locate and image the solar radio bursts(Type Ⅱ&Ⅲ). So all the latest space VLF radio instruments adopt the tripole antenna can do the observations. In this paper, in order to investigate the detection of the solar radio bursts with the space VLF radio explorer, different algorithms are proposed to detect the solar radio bursts with a tripole vector antenna, and simulations have been done with some space VLF radio observations for these algorithms under different conditions. The simulation results show that the vector antenna can locate the radio bursts with a degree-level accuracy. The capability of detecting the solar radio bursts is also analyzed in further for the space VLF radio explorer.

Founded in 2014, Bimonthly

Supervisor: Ministry of Industry and Information Technology

Sponsor: Beijing Institute of Technology, China Aerospace Society Committee for Deep Space Detection Technology

Editor-in-chief: Wu WeiRen

ISSN 2096-9287CN 10-1707/V

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