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Surrogate-assisted optimization for anti-ship missile body configuration considering high-velocity water touching

Chinese Journal of Aeronautics 2023年第12期36卷 268-281页

作者： Nianhui YE Teng LONG Junhui MENG Renhe SHI Baoshou ZHANG School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Key Laboratory of Dynamics and Control of Flight Vehicle Ministry of EducationBeijing 100081China

As a crucial weapon in the sea battle,anti-ship missiles generally employ a sea-skimming penetration strategy to reduce the probability of being detected by the target radar,which greatly increases the risk of touching water caused by sensor errors or random sea *** alleviate the large impact load by high-velocity water touching,a novel anti-ship missile body configuration is proposed in this paper,which is inspired by the idea of hydroplaning.A parametric geometry model is first developed to modify the configuration of the anti-ship missile ***,a structured arbitrary Lagrange-Eulerian based Fluid-Structure Interaction(FSI)model is established to analyze the kinematics parameters of the missile body during the hydroplaning process.A missile body configuration optimization problem is then formulated to minimize the impact load considering several constraints,e.g.,horizontal velocity loss,pitch angle after touching water,and inside capacity for *** to the time-consuming FSI simulation,a Kriging-assisted constrained differential evolution method is utilized to optimize the missile body configuration for reducing the impact *** the optimization process,radial basis function and Kriging are combined with evolutionary operators to lead the search to the vicinity of the optimum *** result shows that the proposed missile body configuration can reduce the impact load by 18.8%compared with the ordinary ***,the optimized configuration can further yield a 17.4%impact load decrease subject to all the constraints and avoid structural damage by the high-velocity water touching,which demonstrates the effectiveness and practicability of the proposed anti-ship missile body configuration and corresponding optimization framework for reducing the impact load.

关键词： Surrogate-assisted optimiza-tion Fluid-structureinteraction Arbitrary Lagrange-Eulerian Missile Conceptual design

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Optimal crater landmark selection based on optical navigation performance factors for planetary landing

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Chinese Journal of Aeronautics 2023年第3期36卷 254-270页

作者： Yi XIU Shengying ZHU Rui XU Maodeng LI School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Key Laboratory of Autonomous Navigation and Control for Deep Space Exploration Ministry of Industry and Information TechnologyBeijing 100081China Key Laboratory of Dynamics and Control of Flight Vehicle Ministry of EducationBeijing 100081China Science and Technology on Space Intelligent Control Laboratory Beijing Institute of Control EngineeringBeijing 100091China

Planetary craters are natural navigation landmarks that widely exist and are easily *** navigation based on crater landmarks has become an important autonomous navigation method for planetary *** to the increase in observed crater landmarks and the limitation of onboard computation,the selection of good crater landmarks has gradually become a research hotspot in the field of landmark-based optical *** paper designs a fast crater landmark selection method,which not only considers the configuration observability of crater subsets but also focuses on the influence on navigation performance arising from the measurement uncertainty and the matching confidence of craters,which is different from other landmark selection *** factor of measurement uncertainty,which is anisotropic,correlated and nonidentically distributed,is quantified and integrated into selection based on crater pairing detection and localization error *** addition,the concept of the crater matching confidence factor is introduced,which reflects the possibility of 2D projection measurements corresponding to 3D *** with the configuration observability factor,the crater landmark selection indicator is ***,the effectiveness of the proposed method is verified by Monte Carlo simulations.

关键词： Crater-based optical navigation Crater landmark selection Crater matching Measurement uncertainty Planetary landing

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Logical stochastic resonance in a cross-bifurcation non-smooth system

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Chinese Physics B 2024年第3期33卷 659-667页

作者：张宇青雷佑铭 School of Mathematics and Statistics Northwestern Polytechnical UniversityXi'an 710072China Ministry of Industry and Information Technology Key Laboratory of Dynamics and Control of Complex Systems Northwestern Polytechnical UniversityXi'an 710072China

This paper investigates logical stochastic resonance(LSR)in a cross-bifurcation non-smooth system driven by Gaussian colored *** this system,a bifurcation parameter triggers a transition between monostability,bistability and *** using Novikov's theorem and the unified colored noise approximation method,the approximate Fokker-Planck equation is *** we derive the generalized potential function and the transition rates to analyze the LSR phenomenon using numerical *** simulate the logic operation of the system in the bistable and tristable regions *** assess the impact of Gaussian colored noise on the LSR and discover that the reliability of the logic response depends on the noise strength and the bifurcation ***,it is found that the bistable region has a more extensive parameter range to produce reliable logic operation compared with the tristable region,since the tristable region is more sensitive to noise than the bistable one.

关键词： logical stochastic resonance bifurcation mean first passage time

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An electromagnetic semi-active dynamic vibration absorber for thin-walled workpiece vibration suppression in mirror milling

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Applied Mathematics and Mechanics(English Edition) 2024年第8期45卷 1315-1334页

作者： Jianghua KONG Bei DING Wei WANG Zhixia WANG Juliang XIAO Hongyun QIU School of Mechanical Engineering Tianjin UniversityTianjin 300350China Tianjin Key Laboratory of Nonlinear Dynamics and Control Tianjin 300350China Key Laboratory of Modern Mechanisms and Equipment Design of the State Ministry of Education Tianjin UniversityTianjin 300350China

As critical components of aircraft skins and rocket fuel storage tank shells,large thin-walled workpieces are susceptible to vibration and deformation during machining due to their weak local *** address these challenges,we propose a novel tunable electromagnetic semi-active dynamic vibration absorber(ESADVA),which integrates with a magnetic suction follower to form a followed ESADVA(follow-ESADVA)for mirror *** system combines a tunable magnet oscillator with a follower,enabling real-time vibration absorption and condition feedback throughout the milling ***,the device supports self-sensing and frequency adjustment by providing feedback to a linear actuator,which alters the distance between *** resolves the traditional issue of being unable to directly monitor vibration at the machining point due to space constraints and tool *** frequency shift characteristics and vibration absorption performance are comprehensively *** and experimental results demonstrate that the prototyped follow-ESADVA achieves frequency synchronization with the milling tool,resulting in a vibration suppression rate of approximately 47.57%.Moreover,the roughness of the machined surface decreases by18.95%,significantly enhancing the surface *** results of this work pave the way for higher-quality machined surfaces and a more stable mirror milling process.

关键词： semi-active dynamic vibration absorber(SADVA) mirror milling selfsensing vibration absorption tuning thin-walled workpiece

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Experimental study on the influence of roadway shape on the evolution of outburst fluid static pressure

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International Journal of Coal Science & Technology 2024年第4期11卷 274-289页

作者： Jiang Xu Xiaomei Wang Liang Cheng Shoujian Peng Hailin Yang Bin Zhou Feng Jiao State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing 400030China College of Safety Science and Engineering Xian University of Science and TechnologyXian 710054ShaanxiChina

To explore the static pressure dynamic disaster mechanism of coal-and-gas outburst(CGO)fluid,the self-developed multifield coupling large-scale physical simulation test system of coal mine dynamic disaster was used to carry out gas outburst and CGO physical simulation tests in straight,L-shaped and T-shaped *** influence of roadway shape on the evolution of static pressure was explored,and the role of pulverized coal in the process of static pressure dynamic disaster was *** results indicated that the static pressure showed a fluctuating downward trend during the outburst *** gas outburst,the middle and front parts of the roadway in the straight section roadway were the most serious areas of static pressure disasters in the three shapes of *** duration and range of high static pressure disaster in L-shaped roadway were larger than those in T-shaped and straight roadways in *** CGO,the most serious area of static pressure disaster in L-shaped and T-shaped roadways moved backward to the middle of the straight section roadway,and there was a rebound phenomenon in the process of static pressure fluctuation decline,which showed the pulse characteristics of *** the outburst,the static pressure dynamic disaster hazard of L-shaped roadway was higher than that of T-shaped roadway,and the static pressure at the bifurcation structure decayed faster than that at the turning structure,which indicated that T-shaped roadway was more conducive to the release of static pressure in roadway,thus reduced the risk of static pressure *** gas outburst,the static pressure attenuation of the fuid in the roadway before and after the turning and bifurcation structure was greater than that of *** peak static pressure and impulse of the fluid during gas outburst were 2 times and 4-5 times that of CGO *** presence of pulverized coal reduced the attenuation of static pressure and the hazard of dynamic disaster,prolonged

关键词： Gas outburst Coal-and-gas outburst.Static pressure Roadway shape Dynamic disaster.Outburst fluid

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Innovative Thin-Walled Structure with Transverse Negative Poisson’s Ratio for High-Performance Crashworthiness

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Acta Mechanica Solida Sinica 2023年第1期36卷 34-44页

作者： Bin Wang Yongtao Sun Tianjin Key Laboratory of Soft Soils and Engineering Environment Tianjin Chengjian UniversityTianjin 300384China Department of Mechanics and Tianjin Key Laboratory of Nonlinear Dynamics and Control Tianjin UniversityTianjin 300350China

In this paper,an innovative type of thin-walled structures,the convex-concave honeycomb columns(CCHCs)with transverse negative Poisson’s ratio(NPR),is proposed for energy absorbers by replacing the cell walls of square honeycomb lattice columns with sine-shaped or zigzag-shaped walls of equal *** simulations show that,under axial impact,contrary to the conventional square honeycomb columns of equal mass,the transverse cross section of NPR CCHC shrinks inward,making the cell walls of CCHC contact and interact sufficiently with each other and thus dissipate the impact energy much more *** suitably adjusting the transverse NPR,the CCHC can have the combined advantages of effective total energy absorption,high specific energy absorption and low maximum peak crushing *** research of this paper provides a new strategy for the design of high-performance energy absorbers widely used in the engineering fields of vehicle engineering,aerospace engineering etc.

关键词： Energy absorbers Convex-concave honeycomb columns(CCHC) Transverse negative Poisson’s ratio Axial impact High-performance crashworthiness

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Ultra-wide band gap and wave attenuation mechanism of a novel star-shaped chiral metamaterial

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Applied Mathematics and Mechanics(English Edition) 2024年第7期45卷 1261-1278页

作者： Shuo WANG Anshuai WANG Yansen WU Xiaofeng LI Yongtao SUN Zhaozhan ZHANG Qian DING G.D.AYALEW Yunxiang MA Qingyu LIN Department of Mechanics Tianjin UniversityTianjin300350China Tianjin Key Laboratory of Nonlinear Dynamics and Control Tianjin UniversityTianjin300350China State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao066004Hebei ProvinceChina

A novel hollow star-shaped chiral metamaterial(SCM)is proposed by incorporating chiral structural properties into the standard hollow star-shaped metamaterial,exhibiting a wide band gap over 1500 *** broaden the band gap,solid single-phase and two-phase SCMs are designed and simulated,which produce two ultra-wide band gaps(approximately 5116 Hz and 6027 Hz,respectively).The main reason for the formation of the ultra-wide band gap is that the rotational vibration of the concave star of two novel SCMs drains the energy of an elastic *** impacts of the concave angle of a single-phase SCM and the resonator radius of a two-phase SCM on the band gaps are *** the concave angle leads to an increase in the width of the widest band gap,and the width of the widest band gap increases as the resonator radius of the two-phase SCM ***,the study on elastic wave propagation characteristics involves analyzing frequency dispersion surfaces,wave propagation directions,group velocities,and phase ***,the analysis focuses on the transmission properties of finite periodic *** solid single-phase SCM achieves a maximum vibration attenuation over 800,while the width of the band gap is smaller than that of the two-phase *** metamaterials exhibit high vibration attenuation capabilities,which can be used in wideband vibration reduction to satisfy the requirement of ultra-wide frequencies.

关键词： metamaterial ultra-wide band gap wave propagation vibration suppression

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Tube-based MPC for Two-Timescale Discrete-Time Nonlinear Processes with Robust control Contraction Metrics 63

Tube-based MPC for Two-Timescale Discrete-Time Nonlinear Pro...

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63rd IEEE Conference on Decision and control, CDC 2024

作者： Guo, Yang Sauerteig, Philipp Streif, Stefan Technische Universität Chemnitz Automatic Control and System Dynamics Laboratory Chemnitz09107 Germany

ISBN: (纸本)9798350316339

A computationally efficient model predictive control scheme is proposed for constrained nonlinear processes with inherent slow and fast dynamics. Specifically, the nonlinear process is approximated by a surrogate model, whose slow state is sampled with a larger time interval than the fast one. This reduces optimization variables and, on the other hand, introduces prediction errors and henceforth may induce constraint violation without further treatments. To mitigate these issues, we tighten constraints by leveraging Robust control Contraction Metrics. Furthermore, a back-up strategy is employed to ensure feasibility over time. The numerical efficiency of this proposed scheme is illustrated with a crops growth process, e.g., in indoor farming. © 2024 IEEE.

关键词： Robust control

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Visualization and characterization of experimental hydraulic fractures interacting with karst fracture-cavity distributions

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1667-1683页

作者： Hanzhi Yang Xin Chang Chunhe Yang Wuhao Guo Lei Wang Guokai Zhao Yintong Guo State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing400044China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China

Karst fracture-cavity carbonate reservoirs,in which natural cavities are connected by natural fractures to form cavity clusters in many circumstances,have become significant fields of oil and gas exploration and *** fracturing is considered as the best method for exploiting carbonate reservoirs;however,previous studies primarily focused on the effects of individual types of geological formations,such as natural fractures or cavities,on fracture *** this study,true-triaxial physical simulation experiments were systematically performed under four types of stress difference conditions after the accurate prefabrication of four types of different fracture-cavity distributions in artificial ***,the interaction mechanism between the hydraulic fractures and fracture-cavity structures was systematically analyzed in combination with the stress distribution,cross-sectional morphology of the main propagation path,and three-dimensional visualization of the overall fracture *** was found that the propagation of hydraulic fractures near the cavity was inhibited by the stress concentration surrounding the *** contrast,a natural fracture with a smaller approach angle(0°and 30°)around the cavity can alleviate the stress concentration and significantly facilitate the connection with the *** addition,the hydraulic fracture crossed the natural fracture at the 45°approach angle and bypassed the cavity under higher stress difference conditions.A new stimulation effectiveness evaluation index was established based on the stimulated reservoir area(SRA),tortuosity of the hydraulic fractures(T),and connectivity index(CI)of the *** findings provide new insights into the fracturing design of carbonate reservoirs.

关键词： Karst fracture-cavity reservoir Fracturing experiment Fracture propagation Cross-sectional morphology Stimulation effectiveness

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A Quasi-Zero Stiffness Nonlinear Absorber Based on Centrifugal Force

A Quasi-Zero Stiffness Nonlinear Absorber Based on Centrifug...

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International Conference on Applied Nonlinear dynamics, Vibration, and control, ICANDVC 2023

作者： Guo, Hulun Cao, Zhiwei Tianjin Key Laboratory of Nonlinear Dynamics and Control Department of Mechanics Tianjin University Tianjin300072 China

ISBN: (纸本)9789819705535

A design approach for quasi-zero stiffness (QZS) nonlinear absorbers for rotor system vibration suppression is proposed in this paper. An example of the QZS nonlinear absorber is designed for a single-disc rotor system considering gyroscopic. The nonlinear absorber consists of a rigid mass ring and four circumferentially distributed nonlinear springs, which are coaxially mounted and rotated together with the disc. The equations of motion of the rotor system with the QZS nonlinear absorber are derived by the Lagrange’s equation. According to the motion equations, it shows that the rigid mass ring reveals a negative stiffness due to the centrifugal forces generated by its vibration. The quasi-zero stiffness is realized by combining the positive stiffness provided by the nonlinear springs and the negative stiffness generated by the centrifugal forces. The stability of the rotor system is compromised at high rotational speed due to the speed-dependent negative stiffness provided by the centrifugal force. Thus, the influence of the linear and nonlinear stiffness on vibration suppression and stability of the rotor system are discussed. The present results indicate that increasing the linear stiffness appropriately can enhance the decay rate of the peak vibration and improve the stability of the rotor system. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.

关键词： Equations of motion

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