Table of Content

28 April 2024, Volume 58 Issue 4 Previous Issue    Next Issue

Aeronautics and Astronautics

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Attitude Planning Method of Satellite Staring Imaging to Aerial Dynamic Target DU Ning, WU Shufan, CHEN Zhansheng, CHEN Wenhui, WANG Shiyao, XU Jiaguo, QIN Dongdong 2024, 58 (4):  411-418.  doi: 10.16183/j.cnki.jsjtu.2022.425 Abstract ( 406 )   HTML ( 60 )   PDF (1661KB) ( 554 )   Save Aimed at the staring imaging requirements of the low earth orbit (LEO) satellite array camera for aerial dynamic targets, a method for target position estimation and staring attitude planning based on image miss-distance of the satellite platform is proposed. Based on the prior knowledge of the flying altitude of the aerial dynamic target, taking the latitude and longitude change rate of the target geography as the state quantity and the central pixel value of the target as the observation, an extended Kalman filter (EKF) is designed to realize the accurate smooth estimation and prediction of the geographical latitude and longitude of the target. On this basis, the attitude and angular velocity of the satellite are planned, the influence of target pixel noise and delay on attitude stability is avoided, and the position estimation of a single satellite to target is realized. The effectiveness of the proposed method is illustrated by a numerical simulation. Figures and Tables | References | Related Articles | Metrics

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Numerical Study of Deformation and Breakup Processes of Water Droplets in Air Flow SANG Xu, JIN Zheyan, YANG Zhigang, YU Fang 2024, 58 (4):  419-427.  doi: 10.16183/j.cnki.jsjtu.2022.414 Abstract ( 351 )   HTML ( 22 )   PDF (2771KB) ( 374 )   Save Aimed at the problem that water droplets are easy to break up during the acceleration process in icing wind tunnel experiment, which makes it difficult for the particle size distribution of water droplets in the test section to conform to the icing weather conditions, the deformation and breakup regime of water droplets with a diameter of 100, 200, 400, 600, 800, 1 000 and 1 200 μm under the action of different air velocities(20, 50, and 80 m/s) are simulated by using the volume of fluid (VOF) method. The results show that under the action of 20 m/s air flow, the water droplet with a diameter of 600 μm does not break. Under the action of 50 m/s air flow, the water droplet with a diameter of 100 μm does not break. With the increase of Weber number, the wavelength of the most destructive wave also increases, and the breakup regime of water droplets changes from bag breakup to bag-plume breakup, to plume-shear breakup, and to shear breakup successively. The droplet breakup regime, including the bag breakup, bag/plume breakup, the plume/sheet-thinning breakup, and the shear breakup, has a significant effect on the ratio of the area of the largest droplet to the initial droplet. Under the condition that the initial drop diameter is the same, as the inlet velocity increases, the area ratio after breakup increases. Figures and Tables | References | Related Articles | Metrics

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Vibration Characteristics of Cylindrical Membrane HUANG Tao, HE Zeqing, SONG Lin 2024, 58 (4):  428-437.  doi: 10.16183/j.cnki.jsjtu.2022.396 Abstract ( 222 )   HTML ( 23 )   PDF (4517KB) ( 222 )   Save Based on the principle of D’Alembert, the nonlinear vibration equation of cylindrical membrane is established, and the analysis and experimental verification of it are conducted. The control equation system for cylindrical membrane vibration problems is established, and the equation system according to the physical equations and boundary conditions of thin diaphragms is simplified and solved, the analytical solution of nonlinear vibration frequency of cylindrical membrane is obtained, and the linear analytical solution is verified by finite element simulation, which shows that the error between theoretical calculation and numerical simulation is small, and the applicability of finite element method to the modal analysis of flexible membrane structure is verified. A 3D laser scanning vibration measurement system is used to test the vibration frequency of cylindrical membranes in the air environment. The finite element analysis software is used to obtain the dry mode and wet mode vibration frequencies of cylindrical membranes and extract the additional mass coefficients of air. The results showed that the test results of the vibration in wet mode have a good consistency with the numerical analysis results, and the influence of the additional quality of the ground air on the cylindrical membrane is in the same order of magnitude as its own mass. Figures and Tables | References | Related Articles | Metrics

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Wavelength Locking of Vertical-Cavity Surface-Emitting Laser in Optically Pumped Magnetometer LUO Manruo, LI Shaoliang, HUANG Yiming, ZHANG Chi, WU Zhaocai, LIU Hua 2024, 58 (4):  438-448.  doi: 10.16183/j.cnki.jsjtu.2022.371 Abstract ( 126 )   HTML ( 18 )   PDF (16216KB) ( 131 )   Save Aimed at the requirements of optically pumped magnetometer (OPM) for miniaturization, low power consumption and laser frequency stability, a wavelength locking control scheme for vertical-cavity surface-emitting laser is proposed. The proposed method of laser wavelength locking based on Doppler absorption optical feedback takes the wavelength of D1 line Fg = 4→Fe = 3 transition in 133Cs atom as the reference. The atom vapor cell in OPM is also used as the working cell for wavelength locking so that the laser wavelength can be locked on the corresponding wavelength of the D1 line transition without any additional setup. The digital proportional integral differential and fuzzy control algorithm is used for laser temperature control and the temperature fluctuation is within ±0.005 ℃. Laser current driving is realized based on current mirror and the current fluctuation is within ±50 nA, which provides a good hardware foundation for laser wavelength locking. Finally, a stable signal output of the OPM for up to two hours under laboratory conditions is realized. Figures and Tables | References | Related Articles | Metrics

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A Mixed Distribution Model of Pointing Error of Aircraft CAO Dongping, JING Qingfeng, ZHONG Weizhi 2024, 58 (4):  449-460.  doi: 10.16183/j.cnki.jsjtu.2022.138 Abstract ( 109 )   HTML ( 14 )   PDF (3225KB) ( 85 )   Save In the space exploration mission, the aircraft will be affected by mechanical shocks, tracking noise and other factors to cause angular micro-vibration, so that the antenna pointing error is always non-zero, which will affect the communication link. Aimed at the disadvantage that typical single distribution models of pointing error such as Gaussian distribution, Rayleigh distribution and Rice distribution ignore the common impact of multiple error sources, a mixed distribution model of pointing error is proposed, which takes multiple error sources into account at the same time, and greatly improves the accuracy of the model. First, the pointing error signal is fitted according to the power spectral density of angular micro vibration signals of multiple spacecraft OLYMPUS, ETS-VI, OICETS and MICIUS. Then, the optimal distribution model is determined by comparing the determination coefficient R2 of the single distribution model and the mixed distribution model with the fitting signal of pointing error. The results show that the mixed distribution model composed of Gaussian distribution and Rice distribution has the highest fitting degree. Taking the Olympus aircraft as an example, the fitting degree of the Gaussian-Rice mixed distribution model is 27.44% higher than that of the single distribution model Rayleigh model, and the bit error rate deviation is reduced by 2.87 dB. Figures and Tables | References | Related Articles | Metrics

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Steady-State Temperature Field Simulation of Injection Mold Based on Finite Volume Method FENG Yangyang, DING Haoliang, HU Pingshan, YAN Bo 2024, 58 (4):  461-467.  doi: 10.16183/j.cnki.jsjtu.2023.040 Abstract ( 150 )   HTML ( 7 )   PDF (6663KB) ( 156 )   Save For steady-state temperature field simulation during cooling stage of plastic injection molding, when the traditional finite volume method (FVM) is used to solve the equivalent heat flux on the cavity surface, the approximate node temperature gradient is often based on the average value in the control volume, but it may not be equal to the local node temperature gradient on the boundary surface. In addition, the calculation of heat flux on each surface in the control volume is independent, which may lead to the non-conservation of heat energy on the control volume. To this end, the improved FVM is modified by taking the heat conservation of steady-state temperature field as a prerequisite and calculating the heat flow of cavity surface based on the node control volume. A numerical simulation software of C++ language based on FVM is developed, which compares the steady-state temperature field of plastic injection molding simulated by the traditional FVM algorithm and the improved FVM algorithm with the results of commercial softwares. The results show that the traditional FVM algorithm can simulate the rough temperature distribution of injection mold, but there is a large calculation error. By improving the equivalent steady-state heat flux calculation method for cavity surface, the calculation error is greatly reduced, which proves that the improved FVM algorithm can predict more accurately the steady-state temperature field in cooling stage. Figures and Tables | References | Related Articles | Metrics

Electronic Information and Electrical Engineering

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An Adaptive Maneuvering Target Tracking Algorithm Based on Fuzzy Inference HAO Liang, HUANG Yinghao, YAO Lixiu, CAI Yunze 2024, 58 (4):  468-480.  doi: 10.16183/j.cnki.jsjtu.2022.314 Abstract ( 169 )   HTML ( 15 )   PDF (6425KB) ( 129 )   Save An adaptive maneuvering target tracking algorithm based on fuzzy inference is proposed to deal with the low adaptive capacity of variable structure interacting multi-model algorithms for target maneuver uncertainty and measurement uncertainty in maneuvering target tracking. A two-stage maneuvering discrimination model based on fuzzy inference is designed, which uses the probability of models and residual weighted norm of the main model to infer the reliability of the main model and the possibility of maneuvering discrimination. The two-stage maneuvering discriminant is introduced into the framework of expected-model augmentation based on likely model-set (EMA-LMS). A kind of fuzzy inference-based EMA-LMS algorithm is proposed to adjust the parameter and strategy of model-set adaption online. This algorithm generates an expected model that is closer to the real motion model and makes better choices for model selection. The simulation results show that the proposed algorithm can strengthen the adaptive capacity for the uncertainty of target maneuver and measurement, and improve accuracy. Figures and Tables | References | Related Articles | Metrics

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Unknown Signal Incremental Recognition Based on Multi-Flow ConvNeXt Network and Mahalanobis Distance Metric XIAO Yihan, LIU Xubin, YU Xiangzhen, ZHAO Zhongkai 2024, 58 (4):  481-491.  doi: 10.16183/j.cnki.jsjtu.2022.426 Abstract ( 224 )   HTML ( 6 )   PDF (1969KB) ( 228 )   Save In order to solve the problem that the signal recognition technology based on deep learning network cannot currently realize the incremental recognition of unknown signals, a method for incremental recognition of such unknown signals, based on the combination of the multi-flow ConvNeXt network and Mahalanobis distance metric (MDM) is proposed. First, the improved multi-flow ConvNeXt network is used to extract the attribute features of signals. Then, the MDM judgement method is used to detect unknown signals, and apply the binary classification for known and unknown signals. Finally, the parameters of the model is automatically updated according to the increasing number of unknown signals. In such way, the model has the ability of self-evolution, and it has the ability to recognize incrementally more types of unknown signals.The simulation results show that the average recognition rate of unknown signals is more than 97%. Figures and Tables | References | Related Articles | Metrics

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Robust State Feedback Design for Uncertain Systems Based on Luenberger Observer ZHAO Dongdong, YAN Lei, ZHOU Xingwen, GENG Zongsheng, YAN Shi 2024, 58 (4):  492-497.  doi: 10.16183/j.cnki.jsjtu.2022.328 Abstract ( 216 )   HTML ( 9 )   PDF (1042KB) ( 237 )   Save This paper proposes a robust state feedback design method based on a new Luenberger observer for uncertain systems with measurement output matrices containing uncertain parameters. First, in view of the problem that it is challenging to measure state variables in practice, an observer is designed through the feedback of the observation state. Considering the situation that the measurement output matrix contains uncertain parameters in the uncertain system, a new Luenberger observer is designed. Then, based on the new Luenberger observer, and combined with the multi-affine representation and the slack variable framework, the convex linear matrix inequality condition related to the Lyapunov function is obtained, and the robust stability analysis based on linear matrix inequalities is conducted for the closed-loop system. Finally, the feasibility of the above condition is tested by an experiment to show the applicability and effectiveness of the proposed method. Figures and Tables | References | Related Articles | Metrics

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Robust Adaptive Algorithm Based on SE(3) and Its Application in SINS/DVL QIAN Leiyuan, QIN Fangjun, LI Kailong, ZHU Tiangao 2024, 58 (4):  498-510.  doi: 10.16183/j.cnki.jsjtu.2022.513 Abstract ( 157 )   HTML ( 4 )   PDF (4131KB) ( 153 )   Save Aimed at the problem that SINS/DVL integrated navigation is vulnerable to interference in complex environment, a robust adaptive algorithm based on SE(3) is proposed. By introducing the Lie group/Lie algebra theory and the robust adaptive strategy into the orthogonal transformed cubature Kalman filter (TCKF), the estimated states of TCKF are made to incorporate the Special Euclidean group (SE(3)), and the state space inconsistency problem is improved. The anomaly measurement is adaptively reconstructed based on the innovation vector, by using the chi-square test and the Huber method. The experimental results of SINS/DVL show that the proposed method has a better spatial consistency and robustness than the traditional methods. Figures and Tables | References | Related Articles | Metrics

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Unmanned Aerial Vehicle Path Planning Algorithm Based on Improved Informed RRT* in Complex Environment LIU Wenqian, SHAN Liang, ZHANG Weilong, LIU Chenglin, MA Qiang 2024, 58 (4):  511-524.  doi: 10.16183/j.cnki.jsjtu.2022.442 Abstract ( 881 )   HTML ( 24 )   PDF (11075KB) ( 747 )   Save To address the problems of long planning time, redundant planning path, and even planning failure caused by local constraints in narrow spaces in the rapid exploring random trees (RRT) algorithm when unmanned aerial vehicle is planning a path in a complex environment, an improved Informed RRT* algorithm is proposed. First, the artificial potential field (APF) method is used to make the sampling points move to the target point in the way of potential field descending, which improves the purpose and directionality of RRT tree expansion. Considering the complexity of the global environment during tree expansion, an adaptive step size is introduced to accelerate the expansion speed of the RRT tree in an unobstructed environment. Then, relevant constraints are added in the process of random tree expansion to ensure the feasibility of the generated paths. After the first reachable path is found, variable elliptic or ellipsoidal sampling domain is used to limit the selection of sampling points and the expansion range of adaptive step size, so as to accelerate the convergence of the algorithm to the asymptotic optimization. Finally, the original algorithm and the improved algorithm are compared in two-dimensional and three-dimensional complex environment. The simulation results show that the improved algorithm can find a better reachable path with a small number of iterations, lock the elliptic or ellipsoidal sampling domain faster and leave more time for path optimization. The improved algorithm performs better in path planning. Figures and Tables | References | Related Articles | Metrics

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Industrial Process Fault Detection Based on Incremental Isometric Mapping and Double Local Density Method FENG Liwei, SUN Liwen, GU Huan, LI Yuan 2024, 58 (4):  525-533.  doi: 10.16183/j.cnki.jsjtu.2022.423 Abstract ( 87 )   HTML ( 4 )   PDF (2253KB) ( 68 )   Save To address the nonlinearity and dynamics of industrial processes, an incremental isometric mapping (IISOMAP) in combination with double local density (DLD) is proposed as a fault detection method (IISOMAP-DLD) based on stream shape learning. First, IISOMAP is used to map the raw data into a low-dimensional manifold feature subspace and a residual subspace. Then, the double local density method is introduced in the two subspaces respectively to construct statistics to monitor the process. Finally, the IISOMAP-DLD method is applied to the Tennessee-Eastman (TE) process, and the experimental results show that IISOMAP-DLD has a higher fault detection rate than the other methods. IISOMAP preserves the intrinsic characteristics of the data and solves the nonlinear problems of the process, while the double local density method can eliminate the dynamic of the process. Figures and Tables | References | Related Articles | Metrics

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Polyester Melt Characteristic Viscosity Prediction Method Under Incomplete Data BI Jinmao, ZHANG Peng, ZHANG Jie, ZHAO Chuncai, CUI Li 2024, 58 (4):  534-544.  doi: 10.16183/j.cnki.jsjtu.2023.011 Abstract ( 137 )   HTML ( 5 )   PDF (10119KB) ( 208 )   Save Characteristic viscosity is a key indicator of the quality of polyester melts, whose accurate prediction can help to identify potential quality problems of polyester melts in advance, adjust the process parameters in time and reduce enterprise losses. Considering the data incompleteness, data time series and high dimensional redundancy of the polyester melt production process, a method is proposed to predict the characteristic viscosity of polyester melt under incomplete data. A missing data generative adversarial nets (MDGAN) with a convolutional neural network discriminator and an attention long short-term memory neural network generator is designed to address the data incompleteness problem caused by the extreme production environment of polyester melts, and the missing data is filled by the adversarial generation mechanism. The extreme gradient boosting-bidirectional gated recurrent unit (XGBoost-BiGRU) is designed to predict the viscosity of polyester melts based on high dimensional redundancy and temporal characteristics prediction. The actual data test results of a polyester fiber manufacturer in Zhejiang show that the filling accuracy of the MDGAN algorithm at different missing rate data sets is better than that of data filling algorithms such as KNN,RF,MICE,and GAIN. The XGBoost-BiGRU characteristic viscosity prediction method has significant advantages over STL-GPR, CAGRU, BiGRU. In combination of MDGAN characteristic viscosity prediction, the method proposed can effectively solve the problem of predicting the characteristic viscosity of polyester melts under incomplete data. Figures and Tables | References | Related Articles | Metrics

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MCR-WPT Efficiency Improvement Based on Metamaterial Interactive Modeling and Analysis FAN Xingming, ZHANG Haonan, ZHANG Xin 2024, 58 (4):  545-554.  doi: 10.16183/j.cnki.jsjtu.2023.025 Abstract ( 172 )   HTML ( 8 )   PDF (7074KB) ( 251 )   Save Metamaterials have special magnetic field control capabilities as a matter of concern and have been applied in the field of magnetically-coupled resonant wireless power transfer (MCR-WPT). It is a challenging study topic to seek a metamaterial designed for the target needs of a specific field. The S-parameter retrieval method and equivalent circuit method have received wide attention as the commonly used design methods for metamaterials. The parameters of metamaterials are obtained by repeated simulations, this design process is time-consuming. In this paper, the characteristics of the above two design methods are analyzed and combined. The HFSS and MATLAB software are used to interactively design and optimize the metamaterials used for MCR-WPT characteristic improvement, which effectively simplifies the design process. Furthermore, the square and Koch metamaterial units are designed to optimize the efficiency, and the characteristics of the units are analyzed and compared. Finally, an experimental platform of 6.78 MHz MCR-WPT system is built to analyze the influences of metamaterials on efficiency. The experimental results show that the square metamaterial and Koch metamaterial achieve 28.4% and 24.6% of the maximum power transmission efficiency, respectively, which proves that interactive design can more conveniently design metamaterials and improve the transmission efficiency of the MCR-WPT system. Figures and Tables | References | Related Articles | Metrics

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A Coronavirus Herd Immunity Optimizer Based on Swarm Division LI Boqun, SUN Zhifeng 2024, 58 (4):  555-564.  doi: 10.16183/j.cnki.jsjtu.2022.470 Abstract ( 194 )   HTML ( 8 )   PDF (1927KB) ( 193 )   Save Aimed at the drawbacks of coronavirus herd immunity optimizer (CHIO), i.e., slow convergence speed and low optimization accuracy, a CHIO based on swarm division (SD-CHIO) is proposed. Based on the principle of uniform fitness, the initial swarm is divided into two parts, i.e., exploration individuals and exploitation individuals. For exploration individuals, differential mutation and diffuse reflection mutation are adopted in position update in order to enhance the communication among exploration individuals and swarm diversity respectively, so as to improve the exploration capability of the algorithm. For exploitation individuals, an adaptive fast convergence strategy is proposed in position update: elite prediction is conducted based on the incremental method, and an adaptive convergence coefficient is employed to ensure that exploitation individuals can quickly converge to the elite solution, which improves the exploitation capability of the algorithm. The numerical experiments demonstrate that SD-CHIO significantly improves the convergence speed and accuracy of the conventional algorithm, exhibiting better exploration and exploitation capabilities than other meta-heuristic algorithms do as well as certain value in engineering. Figures and Tables | References | Related Articles | Metrics

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FPGA Design of Image Defogging System in Intelligent Tachograph HUANG He, HU Kaiyi, YANG Lan, WANG Hao, GAO Tao, WANG Huifeng 2024, 58 (4):  565-578.  doi: 10.16183/j.cnki.jsjtu.2023.026 Abstract ( 224 )   HTML ( 11 )   PDF (27145KB) ( 185 )   Save In hazy weather, due to the low visibility of traffic roads, the video images collected are degraded and the image information is fuzzy. Considering the problem of low real-time processing of the traditional system, an image defogging system based on the ZYNQ platform is designed and applied to the intelligent driving recorder system. First, aiming at the problems of the traditional dark channel defogging algorithm in the sky region, a sky region segmentation strategy is proposed to correct the image restoration parameters. Then, in order to solve the problem that the pixel ordering of the whole image consumes a lot of resources when calculating the global atmospheric light value, a frame iteration method is proposed to optimize the atmospheric light value by making the advantage of the parallel operation on the FPGA platform, and at the same time, the optimization of guided filtering is realized. Finally, using dual-channel high definition multimedia interface (HDMI) resources, a real-time traffic image video processing experimental platform is established by using one channel of the dual HDMI resources as video input and the other as video processing output, and experimental simulation of the algorithm in this paper is conducted. The experimental results show that the system has a good defogging performance for the traffic video in hazy weather, especially in solving the problem of defogging distortion in the sky area. When the traffic video with a resolution of 1 280×720 is defogged, the processing speed can reach 30 frame/s meeting the real-time requirements. Figures and Tables | References | Related Articles | Metrics

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A Consistency Checking Method for Erasure-Coded Striped Data XU Liangye, SHI Lianxing, SHAN Rongsheng 2024, 58 (4):  579-584.  doi: 10.16183/j.cnki.jsjtu.2024.035 Abstract ( 111 )   HTML ( 10 )   PDF (938KB) ( 93 )   Save Erasure code is commonly used in distributed storage systems. The stripe is the basic unit of consistency check in erasure-coded data, including multiple original stripe units and verification stripe units. In order to reduce the cost of reading for consistency check of erasure-coded striped data and improve the efficiency of erasure-coded data consistency check and reading-after-writing, self-correction data tags (SCDTs) is added to each stripe unit when writing erasure-coded data in striping mode, based on which, the consistency checks of each stripe are implemented. The method proposed can complete the consistency check of a stripe without reading all data units in the stripe, which improves the efficiency of consistency checks by 1.7 to 2.6 times. Moreover, when the number of stripe units updated by written data is less than the critical value, it can effectively reduce the number of Input/Output (IO) interactions for writing. The method proposed can better handle partial updates of striped data sets while improving the efficiency of consistency checks. Figures and Tables | References | Related Articles | Metrics