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Vibration Reduction by a Partitioned Dynamic Vibration Absorber with Acoustic Black Hole Features

Chinese Journal of Mechanical Engineering 2024年第4期37卷 120-134页

作者： Xiaoning Zhao Chaoyan Wang Hongli Ji Jinhao Qiu Li Cheng State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China Nanjing institute of Information Technology Nanjing 210016China Department of mechanical Engineering Hong Kong Polytechnic UniversityKowloon 999077Hong KongChina

Vibration quality is a vital indicator for assessing the progress of modern *** dynamic vibration absorber(DVA)based on the acoustic black hole(ABH)feature is a new passive control method that manipulates *** offers efficient energy focalization and broad-spectrum vibration suppression,making it highly promising for applications in large equipment such as aircraft,trains,and *** previous advancements in ABH-DVA development,certain challenges remain,particularly in ensuring effective coupling with host structures during *** address these issues,this study proposes a partitioned ABH-featured dynamic vibration absorber(PABH-DVA)with partitions in the radial direction of the *** employing a plate as the host structure,simulations and experiments were conducted,demonstrating that the PABH-DVA outperforms the original symmetric ABH-DVA in terms of damping *** study also calculated and compared the coupling coefficients of the two ABH-DVAs to uncover the mechanism behind the enhanced *** results revealed that the PABH-DVA exhibits more coupled modes,occasionally with lower coupling coefficients than the symmetric *** influence of frequency ratio and modal mass was further analyzed to explain the reasons behind the PABH-DVA's superior damping ***,the study discussed the impact of the number of slits and their *** research further explains the coupling mechanism between the ABH-DVA and the controlled structure,and provides new ideas for the further application of ABH in engineering.

关键词： Acoustic black hole Vibration control Dynamic vibration absorber Coupling analysis

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Comparison of composite control strategies for maintaining lighting conditions

Comparison of composite control strategies for maintaining l...

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第35届中国过程控制会议

作者： Jun Shi Yuchen Jiang Zheyuan Ning Yunfeng Zhang Hao Luo School of astronautics Harbin Institute of Technology

This paper studies how the spacecrafts maneuver in order to take and maintain good lighting conditions. The objective is to solve for the impulse signals required for spacecraft orbit maneuvers. The paper considers two groups of spacecrafts and compares the strategies of using the Lambert transfer and a heuristic optimization algorithm. Simulation experiments show that single-impulse maneuver optimization consumes less energy compared to the Lambert transfer, whereas the Lambert transfer achieves better results in taking and maintaining good lighting conditions. The outcome of this work provides guidance for simulation-based composite control strategies for maintaining satisfactory lighting conditions.

关键词： Composite Control Strategy Heuristic Optimization Algorithm Lambert Problem

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Highly efficient 1D p-Te/2D n-Bi_(2)Te_(3) heterojunction self-driven broadband photodetector

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Nano Research 2024年第3期17卷 1864-1874页

作者： Chenchen Zhao Dongbo Wang Jiamu Cao Zhi Zeng Bingke Zhang Jingwen Pan Donghao Liu Sihang Liu Shujie Jiao Tianyuan Chen Gang Liu Xuan Fang Liancheng Zhao Jinzhong Wang School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China School of astronautics Harbin Institute of TechnologyHarbin 150001China Center for High Pressure Science and Technology Advanced Research Shanghai 201203China State Key Laboratory of High Power Semiconductor Lasers Changchun University of Science and TechnologyChangchun 130022China

Broadband photodetectors with self-driven functions have attracted intensive scientific interest due to their low energy consumption and high optical ***,high-performance broadband self-driven photodetectors are still a significant challenge due to the complex fabrication processes,environmental toxicity,high production costs of traditional 3D semiconductor materials and sharply raised contact resistance,severe interfacial recombination of 2D materials and 2D/3D mixed dimension ***,1D p-Te/2D n-Bi_(2)Te_(3) heterojunctions are constructed by the simple and low-cost hydrothermal method.1D p-Te/2D n-Bi_(2)Te_(3) devices are applied in photoelectrochemical(PEC)photodetectors,with their high performance attributed to the good interfacial contacts reducing interface *** device demonstrated a broad wavelength range(365–850 nm)with an Iph/Idark as high as *** R_(i),D^(*),and external quantum efficiency(EQE)values of the device were as high as 12.07 mA/W,5.87×10^(10) Jones,and 41.05%,respectively,which were significantly better than the performance of the prepared Bi_(2)Te_(3) and Te devices.A comparison of the freshly fabricated device and the device after 30 days showed that 1D p-Te/2D n-Bi_(2)Te_(3) had excellent stability with only 18.08%decay of *** is anticipated that this work will provide new emerging material for future design and preparation of a high-performance self-driven broadband photodetector.

关键词： topological insulating states interfacial recombination self-driven 1D p-Te/2D n-Bi_(2)Te_(3) photodetector

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Compensated acceleration feedback based active disturbance rejection control for launch vehicles

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Chinese Journal of Aeronautics 2024年第4期37卷 464-478页

作者： Xiaoyan ZHANG Wenchao XUE Zibo LIU Ran ZHANG Huifeng LI Key Laboratory of Systems and Control Institute of Systems ScienceAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China School of astronautics Beihang UniversityBeijing 100191China

In this paper, the attitude tracking and load relief control problems against wind disturbances and uncertain aerodynamics as well as the engine thrust of launch vehicles are ***, a framework of Compensated Acceleration Feedback based Active Disturbance Rejection Control(CAF-ADRC) is established to achieve both desired attitude tracking and load relief performances. In particular, the total disturbance that includes the effects caused by both aerocoefficient perturbations and disturbances is estimated by constructing an Extended State Observer(ESO) to achieve attitude tracking. Furthermore, combined with the normal acceleration due to the engine thrust, the accelerometer measurement is also compensated to enhance the load relief ***, the quantitative analysis of ESO and the entire closed-loop system are studied. It can be concluded that the desired attitude tracking and load relief performances can be achieved simultaneously under the proposed approach. Besides, tuning laws of the proposed approach are systematically given, which are divided into ESO, Proportional Derivative(PD) and Compensated Acceleration Feedback(CAF) modules. Moreover, the performances under CAF-ADRC approach can be better than those under CAF based PD(CAF-PD) approach by tuning load relief ***, the approach presented is applied to a typical control problem of launch vehicles with wind disturbances and parameter uncertainties.

关键词： Launch vehicles Uncertainty analysis Active disturbance rejection control(ADRC) Load relief control Extended state observer(ESO)

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Icephobic materials and strategies:From bio-inspirations to smart systems

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Droplet 2024年第3期3卷 1-26页

作者： Xinlin Li Yan Liu Zhichun Zhang Yanju Liu Jinsong Leng Centre for Composite Materials and Structures School of AstronauticsHarbin Institute of TechnologyHarbinChina Key Laboratory of Bionic Engineering(Ministry of Education) College of Biological and Agricultural EngineeringJilin UniversityChangchunChina institute of Structured and Architected Materials Liaoning Academy of MaterialsShenyangChina Department of Astronautical Science and Mechanics Harbin Institute of TechnologyHarbinChina

Unwanted ice formations may cause severe functional degradations of facilities and also have a negative impact on their *** and removing ice accumula-tion is always a hot topic in the industrial and technological *** functional surfaces have been greatly studied for several decades and have proved to be excel-lent candidates for passive anti-/deicing ***,the drawbacks limit their potential industrial uses under harsh conditions,like low temperatures and high *** researches on bionic surfaces are focused on a certain function of nat-ural creatures and their underlined fundamental theories are revealed by taking the interface as the ***,living organisms,either plants or animals,are often sensitive and responsive to their surroundings,avoiding risks and even self-repairing upon *** this prospect,a novel view of the bionic icephobic materials has been proposed in the present review,which is expected to be studied and designed by taking the biological species as a *** two representative icephobic mate-rials,the anti-/deicing theories of superhydrophobic and slippery surfaces are first ***,the recent progress of smart icephobic strategies is summarized from interfaces to *** aim to provide new bionic insights on designing future icephobic strategies.

关键词： removing smart summarized

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Phase-Field Simulation of Sintering Process:A Review

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Computer Modeling in Engineering & Sciences 2024年第8期140卷 1165-1204页

作者： Ming Xue Min Yi State Key Laboratory ofMechanics and Control forAerospace Structures&institute for Frontier Science&Key Laboratory for Intelligent Nano Materials and Devices of Ministry of Education&College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics(NUAA)Nanjing210016China

Sintering,a well-established technique in powder metallurgy,plays a critical role in the processing of high melting point materials.A comprehensive understanding of structural changes during the sintering process is essential for effective product *** phase-field method stands out for its unique ability to simulate these structural *** its widespread application,there is a notable absence of literature reviews focused on its usage in sintering ***,this paper addresses this gap by reviewing the latest advancements in phase-field sintering models,covering approaches based on energy,grand potential,and entropy *** characteristics of various models are extensively discussed,with a specific emphasis on energy-based models incorporating considerations such as interface energy anisotropy,tensor-form diffusion mechanisms,and various forms of rigid particle motion during ***,the paper offers a concise summary of phase-field sintering models that integrate with other physical fields,including stress/strain fields,viscous flow,temperature field,and external electric *** conclusion,the paper provides a succinct overview of the entire content and delineates potential avenues for future research.

关键词： Phase-field model review sintering additive manufacturing

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Integral precession calibration method of PIGA on linear vibration table

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Chinese Journal of Aeronautics 2024年第3期37卷 219-236页

作者： Chuang SUN Shun-qing REN Jun-wei CAO Ru HUO Department of Automation Tsinghua UniversityBeijing 100084China School of astronautics Harbin Institute of TechnologyHarbin 150001China Beijing National Research Center for Information Science and Technology Tsinghua UniversityBeijing 100084China Faculty of Information technology Beijing University of TechnologyBeijing 100124China

Linear vibration table can provide harmonic accelerations to excite the nonlinear error terms of Pendulous Integrating Gyro Accelerometer(PIGA).Integral precession calibration method is proposed to calibrate PIGA on a linear vibration table in this *** on the precise expressions of PIGA’s inputs,the error calibration model of PIGA is *** angular velocity errors of PIGA are suppressed by integer periodic precession and the errors caused by non-integer periods vibrating are *** complete calibration process,including planning,preparation,PIGA testing,and coefficient identification,is designed to optimize the test operations and evaluate the calibration *** effect of the main errors on calibration uncertainty is analyzed and the relative sensitivity function is proposed to further optimize the test *** and simulation results verify that the proposed 10-position calibration method can improve calibration uncertainties after compensating for the related *** order of calibration uncertainties of the second-and third-order coefficients are decreased to 10^(-8)(rad.s^(-1))/g^(2)and 10^(-8)(rad.s^(-1))/g3,*** with the other two classical calibration methods,the calibration uncertainties of PIGA’s nonlinear error coefficients can be effectively reduced and the proportional residual errors are decreased less than 3×10-6(rad.s^(-1))/g by using the proposed calibration method.

关键词： PIGA Linear vibration table Vibration measurement Calibration Error analysis Uncertainty analysis

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Ship recognition based on HRRP via multi-scale sparse preserving method

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Journal of Systems Engineering and Electronics 2024年第3期35卷 599-608页

作者： YANG Xueling ZHANG Gong SONG Hu College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China Key Lab of Radar Imaging and Microwave Photonics Ministry of EducationNanjing 210016China Nanjing Marine Radar institute Nanjing 210016China

In order to extract the richer feature information of ship targets from sea clutter, and address the high dimensional data problem, a method termed as multi-scale fusion kernel sparse preserving projection(MSFKSPP) based on the maximum margin criterion(MMC) is proposed for recognizing the class of ship targets utilizing the high-resolution range profile(HRRP). Multi-scale fusion is introduced to capture the local and detailed information in small-scale features, and the global and contour information in large-scale features, offering help to extract the edge information from sea clutter and further improving the target recognition accuracy. The proposed method can maximally preserve the multi-scale fusion sparse of data and maximize the class separability in the reduced dimensionality by reproducing kernel Hilbert space. Experimental results on the measured radar data show that the proposed method can effectively extract the features of ship target from sea clutter, further reduce the feature dimensionality, and improve target recognition performance.

关键词： ship target recognition high-resolution range profile(HRRP) multi-scale fusion kernel sparse preserving projection(MSFKSPP) feature extraction dimensionality reduction

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Photoacoustic elastography based on laser-excited shear wave

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Journal of Innovative Optical Health Sciences 2024年第3期17卷 56-72页

作者： Yang Liu Ruoyi Shi Gang Li Mingjian Sun School of astronautics Harbin Institute of TechnologyHarbin 150000P.R.China School of Information Science and Engineering Harbin Institute of TechnologyWeihai 264200P.R.China

Elastography can be used as a diagnostic method for quantitative characterization of tissue hardness information and thus,differential changes in pathophysiological states of *** this study,we propose a new method for shear wave elastography(SWE)based on laser-excited shear wave,called photoacoustic shear wave elastography(PASWE),which combines photoacoustic(PA)technology with ultrafast ultrasound *** using a focused laser to excite shear waves and ultrafast ultrasonic imaging for detection,high-frequency excitation of shear waves and noncontact elastic imaging can be *** laser can stimulate the tissue with the light absorption characteristic to produce the thermal expansion,thus producing the shear *** frequency of shear wave induced by laser is higher and the frequency band is *** tracking the propagation of shear wave,Young’s modulus of tissue is reconstructed in the whole shear wave propagation region to further evaluate the elastic information of *** feasibility of the method is verified by *** with the experimental results of supersonic shear imaging(SSI),it is proved that the method can be used for quantitative elastic imaging of the *** addition,compared with the SSI method,this method can realize the noncontact excitation of the shear wave,and the frequency of the shear wave excited by the laser is higher than that of the acoustic radiation force(ARF),so the spatial resolution is *** to the traditional PA elastic imaging method,this method can obtain a larger imaging depth under the premise of ensuring the imaging resolution,and it has potential application value in the clinical diagnosis of diseases requiring noncontact quantitative elasticity.

关键词： Elastography shear wave photoacoustic Young's modulus

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Fractional Gradient Descent RBFNN for Active Fault-Tolerant Control of Plant Protection UAVs

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Computer Modeling in Engineering & Sciences 2024年第3期138卷 2129-2157页

作者： Lianghao Hua Jianfeng Zhang Dejie Li Xiaobo Xi School of Mechanical Engineering Yangzhou UniversityYangzhou225009China College of Intelligent Manufacturing Yangzhou Polytechnic InstituteYangzhou225009China School of Automation Nanjing University of Aeronautics and AstronauticsNanjing211106China

With the increasing prevalence of high-order systems in engineering applications, these systems often exhibitsignificant disturbances and can be challenging to model accurately. As a result, the active disturbance rejectioncontroller (ADRC) has been widely applied in various fields. However, in controlling plant protection unmannedaerial vehicles (UAVs), which are typically large and subject to significant disturbances, load disturbances andthe possibility of multiple actuator faults during pesticide spraying pose significant challenges. To address theseissues, this paper proposes a novel fault-tolerant control method that combines a radial basis function neuralnetwork (RBFNN) with a second-order ADRC and leverages a fractional gradient descent (FGD) *** integrate the plant protection UAV model’s uncertain parameters, load disturbance parameters, and actuatorfault parameters and utilize the RBFNN for system parameter identification. The resulting ADRC exhibits loaddisturbance suppression and fault tolerance capabilities, and our proposed active fault-tolerant control law hasLyapunov stability implications. Experimental results obtained using a multi-rotor fault-tolerant test platformdemonstrate that the proposed method outperforms other control strategies regarding load disturbance suppressionand fault-tolerant performance.

关键词： Radial basis function neural network plant protection unmanned aerial vehicle active disturbance rejection controller fractional gradient descent algorithm

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