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Dynamic Model and Motion Characteristics of an Underwater Glider with Manta-inspired Wings

Journal of Bionic Engineering 2022年第1期19卷 1-15页

作者： Yaqiang Zhu Yuhong Liu Lianhong Zhang Yanhui Wang Wendong Niu Cheng Huang Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education School of Mechanical EngineeringTianjin UniversityTianjin300350China The Joint Laboratory of Ocean Observing and Detection Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao266237China

An underwater glider with bionic wings controlled by two operating modes is proposed to perform a variety of marine exploration *** system composition of the vehicle and the structural design of wings inspired by manta ray are *** bionic wings can keep outstretched or realize oscillating motions according to the operating modes of the vehicle.A universal dynamic model of the vehicle was derived from multibody ***,sailing and steering motions were simulated based on the dynamic model to illustrate the dynamic behaviors of the vehicle under different types of propulsion *** results obtained through simulated calculation are basically consistent with the experimental data,which indicate that the developed dynamic model is applicable to describe the motion characteristics of the *** were conducted in coastal area to analyze the propulsive characteristics of the bionic wings and sea trials involving multifarious motions were carried out,the applicability of the vehicle in marine environment was verified.

关键词： Underwater glider Bionic wing Oscillatory propulsion Dynamic model

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Optimal Matching Analysis of Net Buoyancy and Pitching Angle for Underwater Gliders

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China Ocean Engineering 2022年第5期36卷 697-706页

作者： YANG Ming LIANG Yan WANG Yan-hui YANG Shao-qiong Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education School of Mechanical EngineeringTianjin UniversityTianjin 300350China The Joint Laboratory of Ocean Observing and Detection Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China

Control parameter optimization is an efficient way to improve the endurance of underwater gliders(UGs),which influences their gliding efficiency and energy *** paper analyzes the optimal matching between the net buoyancy and the pitching angle and proposes a segmented control strategy of *** optimization of this strategy is established based on the gliding range model of UG,which is solved based on the approximate model,and the variations of the optimal control parameters with the hotel load are *** optimization results indicate that the segmented control strategy can significantly increase the gliding range when the optimal matching between the net buoyancy and the pitching angle is reached,and the increase rate is influenced by the hotel *** gliding range of the underwater glider can be increased by 10.47%at a hotel load of 0.5 *** optimal matching analysis adopted in this study can be applied to other UGs to realize endurance improvement.

关键词： optimal matching analysis underwater glider approximate model technology gliding range model

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Unified Inertia Modelling and Quantitative Comparative Analysis between Grid-Following and Grid-Forming Converters 10

Unified Inertia Modelling and Quantitative Comparative Analy...

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10th IEEE International Power Electronics and Motion Control Conference, IPEMC 2024 ECCE Asia

作者： Li, Xiaoyu Li, Zheyu Zhou, Shiying Ma, Jingran Zhu, Donghai Zou, Xudong Huazhong University of Science and Technology Power Electronics and Energy Management Key Laboratory Ministry of Education of China China Hubei Key Laboratory of Marine Electromagnetic Detection and Control China Wuhan Second Ship Design and Research Institute China

ISBN: (纸本)9798350351330

Grid-following (GFL) and grid-forming (GFM) converters with inertia control are essential ways to address the 'low-inertia' system problem. However, due to the different structures of the two converters, their inertia response performance is hard to evaluate. Several studies have attempted to compare them through simulation, but the absence of a unified and quantifiable inertia metric makes it difficult to get a fundamental comparison. To tackle this issue, the magnitude-phase motion equations for the two converters are derived in this paper, with the dynamic behaviors of multiple control loops considered. The structure of the swing equation is utilized to provide a unified description, and the extracted equivalent inertia is used to express their inertia characteristics quantitatively. Finally, the performance of the two converters is compared by simulation based on equivalent inertia. © 2024 IEEE.

关键词： Equations of motion

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Analysis of DOA Estimation Under Mixed-resolution Based on Conformal Arrays 16

Analysis of DOA Estimation Under Mixed-resolution Based on C...

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16th International Conference on Signal Processing Systems, ICSPS 2024

作者： Gu, Shenao Guo, Muran Key Laboratory of Advanced Marine Communication and Information Technology AVIC United Technology Center for Electromagnetic Spectrum Collaborative Detection and Intelligent cognition College of Information and Communication Engineering Harbin Engineering University Harbin150001 China

ISBN: (纸本)9781510689251

Conformal antennas typically utilize short dipoles to reduce space occupation. Conformal antenna arrays are essentially polarization-sensitive arrays with broad applicability and enhanced anti-interference capabilities. However, a practical issue that needs to be addressed is the high power consumption and resource usage resulting from high-resolution analog-to-digital converters (ADCs). In this paper, we introduce the mixed-resolution quantization method into the conformal array to alleviate the pressure on resource transmission by partially reducing the quantization resolution. The receive signal model is constructed in this paper, and a rank-deficient MUSIC algorithm suitable for the proposed scheme is developed. The direction of arrival (DOA) parameters, as well as the polarization parameters, are estimated with considerable accuracy. The power consumption and system cost are effectively reduced with a small sacrifice on parameter estimation accuracy. Numerical simulations validate the feasibility of proposed mixed-quantized conformal array. © 2025 SPIE.

关键词： Direction of arrival

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Simulation for the Underwater Power Supply System Based on Underwater Inverter Scheme 7

Simulation for the Underwater Power Supply System Based on U...

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7th IEEE International Electrical and Energy Conference, CIEEC 2024

作者： Li, Chujun Zhang, Junzhao Jiang, Dong Guo, Jiangyan Ouyang, Hui Huazhong University of Science and Technology Wuhan430074 China CNOOC Research Institute Ltd Beijing100028 China Hubei Key Laboratory of Marine Electromagnetic Detection and Control Wuhan430205 China

ISBN: (纸本)9798350359558

With the increasing global exploration of offshore oil and gas, underwater power supply systems have longer power supply distances and require more electrical equipment. So underwater power supply systems based on underwater transformers are challenging to meet extraction demands due to its high cost. In this case, the systems implementing the underwater inverter scheme have lower costs. This paper simulates the underwater power supply system based on an underwater inverter scheme. The load type is compressors. The motor control method is Constant Voltage-to-Frequency Ratio Control. The rectification section of the variable frequency drive uses non-controlled rectifier. The inverter section of the variable frequency drive uses an NPC/H-Bridge five-level inverter. Simulation for the motors' start-up process and harmonic analysis during the steady state. Compared with the scheme of the underwater transformer, the underwater inverter scheme has lower costs and lower *** is suitable for power supply systems with longer submarine cables. © 2024 IEEE.

关键词： Electric loads

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Three-dimension holographic numerical simulation of gravity anomalies

Three-dimension holographic numerical simulation of gravity ...

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2023 International Conference on Frontiers of Ocean Science and technology, ICFOST 2023

作者： Zhu, Dexiang Dai, Shikun Chen, Qingrui Tian, Hongjun Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring Ministry of Education Central South University HUNAN Changsha410083 China Key Laboratory of Non-ferrous Resources and Geological Hazard Detection Central South University HUNAN Changsha410083 China College of Meteorology and Oceanography National University of Defense Technology HUNAN Changsha410073 China

In gravity-anomaly-based prospecting, it is difficult to achieve large-scale and high-precision inversion imaging of complex geological models. To address this issue, this paper proposes a three-dimensional holographic numerical simulation method for gravity anomalies. This method transforms the 3D partial differential equation of gravity potential into many independent 1D differential equations with different wavenumbers by performing a 2D Fourier transform along the horizontal direction. It decomposes a large-scale 3D numerical modeling problem into many 1D numerical modeling problems, which greatly reduces the computation and memory requirements of modeling, and each 1D differential equation is independent, so it has high parallelism. The vertical direction is reserved as the spatial domain, which has strict upper and lower boundary conditions;The horizontal 2D Fourier transform uses a holographic Fourier transform (Holo-FT) with a full interval of integration, consistent with the physical boundary in the horizontal direction, thus the physical information of the gravity potential described by the three-dimensional partial differential equation is fully and accurately simulated. Using the high parallelism of the algorithm, the CPU is used for parallel solving ordinary differential equations, while the GPU is used for parallel computing of Holo-FT, which implements the CPU-GPU parallel acceleration scheme and further improves the efficiency of this algorithm. © Published under licence by IOP Publishing Ltd.

关键词： Numerical methods

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0−12 Hour QPFs of HRRR-TLE Using Optimized Probability-Matching Method:Taking hunan Province as an Example

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Journal of Tropical Meteorology 2024年第4期30卷 361-372页

作者： LIU Jin-qing MAO Zi-yi DAI Guang-feng YANG Zhao-li PENG Xuan College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410073 China Hunan Meteorological Observatory Hunan Meteorological BureauChangsha 410118 China Guangzhou Institute of Tropical and Marine Meteorology/Guangdong Provincial Key Laboratory of Regional Numerical Weather Prediction China Meteorological AdministrationGuangzhou 510641 China Key Laboratory of High Impact Weather(Special) China Meteorological AdministrationChangsha 410073 China

In real-time operations,the minutely/hourly updated high-resolution rapid refresh(HRRR)system is one of the most expensive numerical weather prediction(NWP)*** on a twenty-member HRRR-time-lagged-ensemble(HRRR-TLE)system developed from two real-time convection-permitting HRRR models,CMA-GD(R3)and CMA-SH3,from the China Meteorological Administration(CMA),this study proposes an optimized probability-matching(OPM)technique to improve 0−12 h quantitative precipitation forecasts(QPFs)based on the correlation and error relationships between ensemble forecasts and observations during the training ***,a series of sensitivity experiments using different cost functions and optimized ratios was conducted to further improve OPM *** results indicate that:(1)In the HRRR-TLE system,there is no always optimal member in both weak rain and severe rain forecasts,as measured by the equitable threat score(ETS)and bias extent(BE)at four thresholds(1+,5+,10+,and 20+mm h^(-1);e.g.,“1+”means≥1).(2)Compared with the HRRR-TLE system,the QPFs generated by the traditional PM technique showed a notable increase in ETS and a decrease in BE at all of the above *** with the traditional probability-matching method(PM),OPM can generate more skillful forecasts on both spatial representations and rain rates by using the sliding-weight method and optimized ensembles,respectively.(3)In particular,in the 20+mm h^(-1)forecasts,which are often difficult to predict,the ETS of the optimal OPM test,with a 20%optimization ratio and symmetric mean absolute percentage error cost function,increased by 64.6%,and the BE decreased by 5.7%,relative to ***,OPM shows good stability in both daytime and nighttime periods.

关键词： high-resolution rapid refresh convection-permitting time-lagged probability-matching CMA-GD(R3) CMA-SH3

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Two-dimensional Gauss-Newton inversion based on marine CSEM data 3

Two-dimensional Gauss-Newton inversion based on marine CSEM ...

引用

3rd International Conference on Geology, Mapping and Remote Sensing, ICGMRS 2022

作者： Guo, Tianyu Guo, Zhenwei Liu, Ying Liu, Jianxin Central South University Hunan Provincial Key Laboratory of Non-ferrous Resources and Geological Hazard Detection School of Geosciences and Info-physics Changsha China Evaluation and Detection Technology Laboratory of Marine Mineral Resources Qingdao National Laboratory for Marine Science and Technology China Key Lab of Submarine Geosciences and Prospecting Techniques Moe and College of Marine Geosciences Ocean University of China Qingdao China

ISBN: (数字)9781665485951

ISBN: (纸本)9781665485951

With development and continuous improvement of methods and technologies, more and more attention has been paid to research of marine controllable source electromagnetic inversion. How to develop a fast and practical marine controllable source electromagnetic inversion method is one of the current research focuses and hot spots. So it is necessary for the development of marine controllable source electromagnetic to study the 2D fast, reasonable and effective inversion, which has important theoretical and practical significance. In this paper, the traditional Gauss-Newton inversion is carried out on the basis of the adaptive finite element forward simulation, and the simulation data and the Occam inversion results are systematically analyzed and compared. The classical model inversion results show that both Occam inversion and Gauss-Newton inversion can invert the anomalies well and the inversion results have their own advantages and disadvantages. Occam inversion RMS is low, the result is smoother, the convergence is stable;the Gauss-Newton inversion time is short, and the number of iterations is small. This is helpful for the later marine controllable source electromagnetic method data interpretation and application. © 2022 IEEE.

关键词： Finite element method

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Underwater arbitrary ranging based on chirped pulse interferometry with a mode-locked laser

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Journal of Lightwave technology 2025年第11期43卷 5235-5243页

作者： Shi, Haonan Zhao, Haihan Xu, Xinyang Zhu, Zhiwei Zhai, Jingsheng Li, Xiaobo Tianjin University School of Marine Science and Technology Tianjin300072 China Research Institute of China Electronics Technology Group Corporation Science and Technology on Electro-Optical Information Security Control Laboratory No. 53 Tianjin300308 China The Chinese University of Hong Kong Department of Mechanical and Automation Engineering Hong Kong999077 Hong Kong Nanjing University of Aeronautics and Astronautics Key Laboratory of Space Photoelectric Detection and Perception Ministry of Industry and Information Technology Nanjing211106 China

Underwater distance measurement and length sensing, as fundamental functions of geoscience, are integrated into underwater robots and vessels in various forms of sensor payloads and play a crucial role in a wide range of remote sensing applications. Advanced laser-based detection systems and algorithms are essential for underwater tasks, such as detecting damage in underwater pipelines and conducting detailed structural health assessments. In this paper, we experimentally demonstrated an arbitrary underwater ranging system by the chirped pulse interferometry with a mode-locked laser. Water's inherent characteristic introduces dispersion, enabling unique distance discrimination. Adjusting the repetition frequency allows us to acquire the interference spectrum. A long fiber delay line, stabilized by the servo-controlled system, eliminates the ranging dead zone. The widest fringe of the interference spectrum, corresponding to an instantaneous repetition frequency, indicates the arbitrary measured distance. Leveraging a charge-coupled device detection module, we achieved an update rate of 13.5 Hz for the interference spectrum. Experimental results show a precise distance difference within 59.8 μm at the 5 m range underwater without the dead zone. © 2025 IEEE. All rights reserved.

关键词： Laser mode locking

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Effect of Oblique Laser Shock Peening on Fretting Fatigue of FGH95 Powder Superalloy 6

Effect of Oblique Laser Shock Peening on Fretting Fatigue of...

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2024 6th International Conference on Advanced Materials and Ecological Environment, AMEE 2024

作者： Qu, Xiangming Wang, Wenjun Zhao, Yanyun Cao, Jun Zhu, Haiyan Guo, Xiaojun Wang, Xu Zhang, Yongkang College of Mechanical Engineering Hunan Institute of Science and Technology Yueyang Hunan China Guangdong Provincial Key Laboratory of Advanced Manufacturing Technology of Marine Energy Equipment Guangdong University of Technology Guangdong Guangzhou China Foshan Yuantian Mattress Machinery Co. Ltd Guangdong Foshan China AECC Hunan Aviation Powerplant Research Institute Hunan Zhuzhou China

Due to the high-frequency vibration contact of blade tenon, the contact surface of the mortise surface of the turbine disk is prone to fretting wear and fatigue fracture. The effects of shock times of Oblique Laser Shock Peening (LSP) and temperature on the fretting fatigue properties were studied. The fretting fatigue life of Oblique LSP treated samples at room temperature could be increased by 103.0%;At high temperatures, the fretting fatigue life could be increased by 68.5%. Through the analysis of fracture morphology, the fracture developing zone of fretting fatigue and tensile fatigue samples were compared. It is revealed that the wear in the transverse contact pads would promote the initiation of fatigue cracks;Due to the compressive force of the transverse contact pads, the degree of plastic deformation of the fretting specimens would increase, the quasi-cleavage facets appeared, and the tear ridge characteristics were obvious. The results of this paper provide a reference for the Oblique LSP of the FGH95 powder superalloy turbine disk and other aero-engine parts. © Published under licence by IOP Publishing Ltd.

关键词： Fracture

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