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Robust template feature matching method using motion-constrained DCF designed for visual navigation in asteroid landing

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Astrodynamics 2023年第1期7卷 83-99页

作者： Yaqiong Wang Xiongfeng Yan Zhen Ye Huan Xie Shijie Liu Xiong Xu Xiaohua Tong College of Surveying and Geo-Informatics and Shanghai Key Laboratory of Space Mapping and Remote Sensing for Planetary EaplorationTongji UniversityShanghai 200092China Shanghai Institute of Intelligent Science and Technology Shanghai 200092China

A robust and eficient feature matching method is necessary for visual navigation in asteroid-landing *** on the visual navigation framework and motion characteristics of asteroids,a robust and efficient template feature matching method is proposed to adapt to feature distortion and scale change cases for visual navigation of *** proposed method is primarily based on a motion-constrained discriminative correlation filter(DCF).The prior information provided by the motion constraints between sequence images is used to provide a predicted search region for template feature ***,some specific template feature samples are generated using the motion constraints for correlation filter learning,which is beneficial for training a scale and feature distortion adaptive correlation filter for accurate feature ***,average peak-to-correlation energy(APCE)and jointly consistent measurements(JCMs)were used to eliminate false *** captured by the Touch And Go Camera System(TAGCAMS)of the Bennu asteroid were used to evaluate the performance of the proposed *** particular,both the robustness and accuracy of region matching and template center matching are *** qualitative and quantitative results illustrate the advancement of the proposed method in adapting to feature distortions and large-scale changes during spacecraft landing.

关键词： discriminative correlation filter(DCF) motion constraints feature distortion adaptive scale changes adaptive template feature matching

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Whale optimisation algorithm with role labour division for multimodal optimisation

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International Journal of Innovative Computing and Applications 2024年第1期15卷 26-37页

作者： Wu, Bowen Xiao, Renbin School of Artificial Intelligence and Automation Huazhong University of Science and Technology Hubei Wuhan430074 China Institute of Artificial Intelligence Huazhong University of Science and Technology Hubei Wuhan430074 China Key Laboratory of Image Processing and Intelligent Control Ministry of Education of China Huazhong University of Science and Technology Hubei Wuhan430074 China

The multimodal optimisation problem challenges the balance between diversity and convergence, which poses a great degree of challenge to traditional population-based intelligence optimisers. The whale optimisation algorithm has the limitation of easily falling into local optimum when facing multimodal optimisation. To address this problem, this paper proposes a whale optimisation algorithm with role labour division (WOA-RDL). In WOA-RDL, a multi-stage role division of labour mechanism is designed to divide the optimisation process into two stages of group hunting. In the first stage, the task allocation in the hunting process is considered as two types of search tasks: exploration and exploitation. The external environmental stimulus of the task and the internal response threshold of the individual were designed to allow individuals to switch between exploration and exploitation tasks flexibly. In the second stage, the distribution mechanism of different roles was designed to simulate the 'strong to weak' distribution rule for the distribution of results after the hunt. The elite roles are selected to further strengthen their capabilities or remain robust, while the inferior roles are predicted and eliminated to improve the overall optimisation of the population and reduce the risk of falling into a local optimum. The results of the optimisation experiments using multimodal, unimodal, CEC2017 combined functions and CEC2009 dynamic functions to validate the effectiveness of the algorithm. Copyright © 2024 Inderscience Enterprises Ltd.

关键词： Optimization algorithms

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Shear behaviour of anchored jointed rock mass under different engineering conditions considering damage and joint surface morphology

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Underground space 2023年第6期13卷 316-334页

作者： Zenghui Zhao Wei Sun Shaojie Chen Hao Liu College of Energy and Mining Engineering Shandong University of Science and TechnologyQingdao 266590China State Key Laboratory of Strata Intelligent Control and Green Mining Co-founded by Shandong Province and the Ministry of Science and Technology Shandong University of Science and TechnologyQingdao 266590China Department of Petroleum Engineering China University of Petroleum-BeijingBeijing 102249China

According to different geological conditions and engineering disturbance,three dimensional numerical models of anchored jointed rock mass with two kinds of boundary conditions of constant normal load(CNL)and constant normal stiffness(CNS)were constructed considering the ductility damage of rockbolt,the stiffness degradation of grouting layer and the joint surface *** effects of anchorage angle,joint surface morphology,and boundary conditions on the shear performance of anchorage system were analyzed,and the failure characteristics under different working conditions were ***,the analytical solution of shear strength of anchored system was *** show that the larger the anchorage angle is,the more serious the necking phenomenon of rockbolt will *** damage degree of the bonding layer and the horizontal displacement of the bedding rock mass decrease with the increase of the joint surface *** CNL condition is to instantaneously apply high normal stress,and the CNS condition is to gradually form a high normal stress environment through the superposition of increment on the basis of the initial value,which can resist greater transverse *** is equivalent to enhancing the ductility of the *** shear strength of the system increases with the increase of normal stress and normal *** the normal stiffness will underestimate the shear strength.

关键词： Anchored jointed rock mass Normal stress Normal stiffness Progressive damage

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A Novel Structure in PUMA Array for Bandwidth Broadening and Profile Reduction 16

A Novel Structure in PUMA Array for Bandwidth Broadening and...

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16th UK-Europe-China Workshop on Millimetre Waves and Terahertz Technologies, UCMMT 2023

作者： Yao, Chenyang Wang, Hao Cao, Jianyin Li, Xiang Qi, Liang Tian, Zhen Nanjing University of Science and Technology Nanjing China Nanhu Laboratory Jiaxing China Laboratory of Electromagnetic Space Cognition and Intelligent Control Beijing China

ISBN: (纸本)9798350339406

This paper proposed a new method of expanding the bandwidth of PUMA array. By attaching bottom-open vias below the coupling plate, lower operating frequency is available without increasing the profile. This design ultimately performs 8.1:1 bandwidth (2.59-21.0 GHz) at broadside, a scanning range of ±75° in the E-plane with 6.6:1 bandwidth (2.68-17.65 GHz), ±50° in the H-plane with 7.4:1 bandwidth (2.58-19.03 GHz) and ±60° in the D-plane with 7:1 bandwidth (2.6-18.2 GHz) at an overall profile of 0.054λL. © 2023 IEEE.

关键词： Bandwidth

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Airfoil Aerodynamic Force Prediction Based on Graph Neural Networks 43

Airfoil Aerodynamic Force Prediction Based on Graph Neural N...

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43rd Chinese control Conference, CCC 2024

作者： Wang, Guoqing Cao, Junzhe Dalian University of Technology Control Science and Engineering Dalian116024 China Dalian University of Technology Key Laboratory of Intelligent Control and Optimization for Industrial Equipment of Ministry of Education Dalian116024 China

ISBN: (纸本)9789887581581

Aerodynamic force prediction is an important application of deep learning in the field of fluid mechanics. In this paper, a light graph neural network model with residual connections named LRGCN is designed to speed the computational process of the aerodynamic prediction. Comparing with other graph convolutional networks, the LRGCN reduces redundant operations and introduces skip connections, overcomes the limitations of traditional machine learning methods that require geometric airfoil parameters. By using CFD simulation, a dataset of aerodynamic forces for airfoil profiles was generated, where the nodes and edges of the flow field grids are abstracted to build a graph structure for aerodynamic force prediction. This study takes variations of the airfoil shape and pitch angle into consideration, enabling the prediction of lift and drag to be fast. In the numerical experiments, the LRGCN achieves the result that normalized test set loss is around 10-3 and the R2 is higher than 90%, which exhibits stronger robustness and higher accuracy than three other current convolutional models. And the LRGCN runs 60 times faster than the normal CFD method for the same prediction task, which significantly reduces time costs. © 2024 Technical Committee on control Theory, Chinese Association of Automation.

关键词： Computational fluid dynamics

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Design of wideband circularly polarized horn antenna for millimeter wave applications 15

Design of wideband circularly polarized horn antenna for mil...

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15th International Conference on Microwave and Millimeter Wave technology, ICMMT 2023

作者： Quan, Shuanglong Tian, Zhen Li, Xiang Qi, Liang Wang, Hao Nanjing University of Science and Technology Nanjing China Laboratory of Electromagnetic Space Cognition and Intelligent Control Beijing China Nanhu Laboratory Jiaxing China

ISBN: (纸本)9798350338874

In this paper, a millimeter-wave (mmW) wide band right-handed circularly polarized (RHCP) horn antenna is designed based on a polarizer with two 90 degree slots loaded on the inner wall of a circular waveguide. The antenna is fed by a standard rectangular waveguide WR-10 waveguide port, and the antenna excitation signal is converted from linear to circular polarization by a circular polarizer. The principle of the antenna is analyzed, the model is simulated and the parameters are optimized, and the design method for obtaining the left-handed circularly polarized (LHCP) antenna based on the RHCP antenna is given. The simulation results show that the reflectance of the antenna is not higher than -24.5 dB, the RHCP gain is greater than or equal to 13.0 dBi, and the axial ratio (AR) is not higher than 3 dB in the range of 84-110 GHz (26.8% relative bandwidth). The proposed antenna is broadband and circularly polarized, and can be widely used in broadband mmW applications. © 2023 IEEE.

关键词： Millimeter waves

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Flow Field Prediction of Variable Geometry using a Novel Deep CNN Model with Dual-Feature of Flow Regions 43

Flow Field Prediction of Variable Geometry using a Novel Dee...

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43rd Chinese control Conference, CCC 2024

作者： Zhang, Mai J., Cao Dalian University of Technology Control Science and Engineering Dalian116024 China Dalian University of Technology Key Laboratory of Intelligent Control and Optimization for Industrial Equipment of Ministry of Education Dalian116024 China

ISBN: (纸本)9789887581581

Flow field prediction of variable geometry aims for the precise prediction of varying flow fields with complex geometric shapes and their variations. By combining a novel deep convolutional neural network (CNN) model with a Computational Fluid Dynamics (CFD) method, the solution of the Navier-Stokes equation can be effectively approximated with a significant reduction in the corresponding computation time cost. This paper proposes an approach named AM UNet-3 for predicting the flow field of variable geometry, which can directly predict the expected flow field of new shapes after the training of deep CNN through extracting and identifying dual features of flow field regions: geometric information features and multi-class channel features. The AM UNet-3 is a convolutional neural network model that combines a U-Net variant structure with three independent decoders and attention mechanisms. The framework of U-Net can learn the complete numerical solutions of the N-S equations to velocity and pressure fields from ground-truth data. The three independent decoders are used to output the pressure field and the velocity components in the x-direction and y-direction respectively. The embedded channel attention and spatial attention mechanisms can enhance the ability of AM UNet-3 to extract fast-changing boundary layer characteristics. The performances of AM UNet-3, U-Net and UNet-3 are tested and compared on a dataset consisting of flow field data with 981 different geometric shapes. Experiment results show that AM UNet-3 gets the fastest inference and the lowest prediction error in the three methods. Compared with the standard CFD method, AM UNet-3 is able to speed up the computation more than three orders of magnitude. © 2024 Technical Committee on control Theory, Chinese Association of Automation.

关键词： Computational fluid dynamics

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Multi-frame Temporal Modeling for Multi-object Tracking in Satellite Video 2

Multi-frame Temporal Modeling for Multi-object Tracking in S...

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2nd IEEE International Conference on Signal, Information and Data Processing, ICSIDP 2024

作者： Chai, Bingqian Qiao, Tingting Xie, Baorong Wang, Jue Liu, Wenchao Beijing Institute of Technology National Key Laboratory of Science and Technology on Space-Born Intelligent Information Processing Beijing China Shanghai Aerospace Electronic Technology Institute Shanghai China

ISBN: (纸本)9798331515669

With the advancement of remote sensing technology, video satellites have played an increasingly important role in both military and civilian domains, and they are widely used in areas such as military guidance, intelligent transportation, and disaster response. Multi-object tracking (MOT) in satellite video is a crucial research topic in these fields and has made certain progress. However, due to the difficulty of tracking objects in complex scene and low resolution, current MOT methods face issues of low accuracy in satellite video. In this work, we propose a joint-detection-and-tracking method called multi-frame temporal MOT (MFT-MOT). Firstly, a heatmap guided multi-frame temporal modeling method is introduced to extract features with temporal semantic information while suppressing background noise. Then, we utilize a weights-shared encoder-decoder network to facilitate interaction of temporal and spatial information and capture inter-frame object motion tracks at low resolution. Experiments on SAT-MTB dataset shows the effectiveness of our method. © 2024 IEEE.

关键词： Object tracking

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Design of millimeter wave wideband circularly polarized horn antenna based on rectangular waveguide polarizer 15

Design of millimeter wave wideband circularly polarized horn...

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15th International Conference on Microwave and Millimeter Wave technology, ICMMT 2023

ISBN: (纸本)9798350338874

In this paper, a millimeter wave (mmW) wide band right-handed circularly polarized (RHCP) horn antenna is designed with a polarizer in the form of a rectangular waveguide (RW). The antenna is fed by a standard RW WR-10 waveguide port. The designed polarizer can convert the antenna excitation signal from linearly polarized (LP) to circularly polarized (CP). The antenna is analyzed, modeled and simulated. The simulation results show that the S11 ≤-22.13dB, the axial ratio (AR) ≤3dB and the RHCP gain ≥15dBi in the range of 35.3% relative bandwidth (77GHz-110GHz). The proposed antenna is broadband and circularly polarized, and would be widely used in satellite communications and 5G mmW communications. © 2023 IEEE.

关键词： Millimeter waves

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Finite-time Prescribed Performance control with RBFNN for the HFV Longitudinal Model 41

Finite-time Prescribed Performance Control with RBFNN for th...

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第41届中国控制会议

作者： Yuan Zhang Wanwei Huang Kunfeng Lu Honghao Zhong Beijing Aerospace Automatic Control Institute National Key Laboratory of Science and Technology on Aerospace Intelligent Control

ISBN: (数字)9789887581536

ISBN: (纸本)9781665482561

A method for designing the finite-time prescribed performance controller with RBFNN(Radial Basis Function Networks) is proposed for the HFV(Hypersonic Flight Vehicle) longitudinal attitude systems with parameters uncertainties and time-varying ***,the appointed-time prescribed performance functions for outer-loop and inner-loop are designed respectively,which aims to restrain the transient and steady-state performance of command tracking *** with the traditional prescribed performance function,the proposed method can guarantee that the errors convergence to the set stability precision at the appointed ***,the error-transform function is applied to transform the guidance command errors into un-limited boundary,which can ensure the error satisfy the constraint condition by means of controlling the transformed ***,the virtual control law of outer-loop subsystem and the actual control law of inner-loop subsystem are designed independently,and the lumped disturbances are estimated by the RBFNN,a novel finite-time tracking differentiator is applied to avoid the 'explosion of terms' problem in the control law design ***,comparative simulations with parametric uncertainties and time-varying disturbance are performed to demonstrate that the proposed method in this paper can effectively satisfy the prescribed performance constraints.

关键词： Hypersonic flight vehicle Lumped Disturbance Finite-time control Radial Basis Function Networks Finite-time Tracking Differentiator

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