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Neural-LAFC: A Neural Learning Adaptive Flight controller for Tailless Flapping-Wing Robots Under Uncertain Wind Disturbance Conditions

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IEEE Transactions on Aerospace and Electronic systems 2025年

作者： Guo, Qingcheng Zhang, Yichen Mou, Jiawang Liu, Wu Wu, Xiaosheng Lu, Jun-Guo Shanghai Jiao Tong University Department of Automation China Key Laboratory of System Control and Information Processing Ministry of Education of China China National Key Laboratory of Advanced Micro and Nano Manufacture Technology Shanghai200240 China Shanghai Jiao Tong University National Key Laboratory of Advanced Micro and Nano Manufacture Technology China Shanghai Jiao Tong University Department of Micro/Nano Electronics School of Electronic Information and Electrical Engineering Shanghai200240 China Designing Institute of Hubei Space Technology Academy Wuhan China Ministry of Education of China Key Laboratory of System Control and Information Processing Shanghai200240 China

Enabling bio-inspired flapping-wing robots (FWRs) to maintain stable flight in windy environments, similar to real flying creatures, is of significant importance. In this work, a neural learning-based adaptive flight controller (Neural-LAFC) is proposed for the attitude and position control of a tailless FWR under uncertain wind conditions. The key approach involves employing a deep neural network (DNN) that incorporates not only attitude information but also instantaneous flapping angles of the wings to learn the aerodynamic torques that cannot be accurately modeled. The training data are obtained from flight experiments conducted with the FWR in a wind tunnel environment. Subsequently, a composite adaptive law is presented to update a set of linear coefficients. These linear coefficients are utilized to blend the pre-trained basis functions to represent the aerodynamic torques. The tracking errors are shown to exponentially converge to a bounded region, as guaranteed by a Lyapunov function. Based on the learning-based attitude controller, we also develop an adaptive controller for position control. Notably, apart from the training phase, the FWR operates without prior knowledge of wind speed. Experimental results demonstrate that the Neural-LAFC successfully achieves the desired attitude stabilization, target point tracking, and path tracking of the FWR in windy conditions. The proposed control scheme also outperforms baseline controllers in wind disturbance suppression, reducing the root mean square position errors by more than 40% when the FWR is subjected to a horizontal wind within the speed of 180 {cm s{-1}}. © 1965-2011 IEEE.

关键词： Wind tunnels

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Mesenchymal stem cells loaded on 3D-printed gradient poly(e-caprolactone)/methacrylated alginate composite scaffolds for cartilage tissue engineering

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Regenerative Biomaterials 2021年第3期8卷 70-83页

作者： Yanyan Cao Peng Cheng Shengbo Sang Chuan Xiang Yang An Xiaochun Wei Zhizhong Shen Yixia Zhang Pengcui Li Key Lab of Advanced Transducers and Intelligent Control System of the Ministry of Education MicroNano System Research CenterCollege of Information and ComputerTaiyuan University of TechnologyTaiyuan 030024China College of Information Science and Engineering Hebei North UniversityZhangjiakou 075000China Shanxi Key Laboratory of Bone and Soft Tissue Injury Repair Department of OrthopedicsThe Second Hospital of Shanxi Medical UniversityTaiyuan 030001China Department of Plastic Surgery Peking University Third HospitalBeijing 100191China Department of Biomedical Engineering College of Biomedical EngineeringTaiyuan University of TechnologyTaiyuan 030024China

Cartilage has limited self-repair ability due to its avascular,alymphatic and aneural *** combination of three-dimensional(3D)printing and tissue engineering provides an up-and-coming approach to address this ***,we designed and fabricated a tri-layered(superficial layer(SL),middle layer(ML)and deep layer(DL))stratified scaffold,inspired by the architecture of collagen fibers in native cartilage *** scaffold was composed of 3D printed depth-dependent gradient poly(e-caprolactone)(PCL)impregnated with methacrylated alginate(ALMA),and its morphological analysis and mechanical properties were *** prove the feasibility of the composite scaffolds for cartilage regeneration,the viability,proliferation,collagen deposition and chondrogenic differentiation of embedded rat bone marrow mesenchymal stem cells(BMSCs)in the scaffolds were assessed by Live/dead assay,CCK-8,DNA content,cell morphology,immunofluorescence and real-time reverse transcription polymerase chain ***-loaded gradient PCL/ALMA scaffolds showed excellent cell survival,cell proliferation,cell morphology,collagen II deposition and hopeful chondrogenic differentiation compared with three individual-layer ***,our study demonstrates the potential use of the gradient PCL/ALMA construct for enhanced cartilage tissue engineering.

关键词： three-dimensional printing cartilage tissue engineering PCL methacrylated alginate bone marrow mesenchymal stem cells

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High Sensitivity Submicron Scale Temperature Sensor Based on Perovskite Nanoplatelet Lasers

SSRN

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SSRN 2024年

作者： Zhao, Ruofan Tao, Jianxun Xi, Yuying Chen, Jiangzhao Ji, Ting Wang, Wenyan Wen, Rong Cui, Yanxia Chen, Junsheng Lia, Guohui College of Physics and Optoelectronics Key Laboratory of Interface Science and Engineering in Advanced Materials Key lab of Advanced Transducers and Intelligent Control System of Ministry of Education Taiyuan University of Technology Taiyuan030024 China School of Materials Science and Engineering Kunming University of Science and Technology Kunming650093 China Shanxi-Zheda institute of advanced materials and chemical engineering China Nano-Science Center Department of Chemistry University of Copenhagen Universitetsparken 5 CopenhagenDK-2100 Denmark

Submicron scale temperature sensors are crucial for a range of applications, particularly in micro and nanoscale environments. One promising solution involves the use of active whispering gallery mode (WGM) microresonators. These resonators can be remotely excited and read out using free-space structures, simplifying the process of sensing. In this study, we present a submicron-scale temperature sensor with a remarkable sensitivity up to 190 pm/℃ based on a triangular CH3NH3PbI3 nanoplatelet (NPL) laser. Notably, as temperature changes, the peak wavelength of the laser line shifts linearly. This unique characteristic allows for precise temperature sensing by tracking the peak wavelength of the NPL laser. The optical modes are confined within the perovskite NPL, which measures just 85 nanometers in height, due to total internal reflection. Our NPL laser boasts several key features, including a high Q-factor of ~ 2610 and a low laser threshold of about 19.8 µJ cm−2. The combination of exceptional sensitivity and ultra-small size makes our WGM device an ideal candidate for integration into systems that demand compact temperature sensors. This advancement paves the way for significant progress in the development of ultrasmall temperature sensors, opening new possibilities across various fields. © 2024, The Authors. All rights reserved.

关键词： Perovskite

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Numerical Simulation about Effects of Stress on Different Cumulative Second Harmonics

Numerical Simulation about Effects of Stress on Different Cu...

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Far East Forum on Nondestructive Evaluation/Testing: New Technology & Application (FENDT)

作者： Xiao-Chuan Niu Wen-Lin Yang Li-Qiang Zhu Hong-Mei Shi Xing-Hong Zhu School of Mechanical Electronic and Control Engineering Beijing Jiaotong University Beijing China Frontiers Science Center for Smart High-speed Railway System Beijing China Key Laboratory of Vehicle Advanced Manufacturing Measuring and Control Technology Ministry of Education Beijing Jiaotong University Beijing China China Railway Lanzhou Group Co. Ltd. Lanzhou China

Nonlinear ultrasonic guided waves technology has shown excellent application potential in the field of structural stress testing due to its unique nonlinear characteristics and long distance detection range. However, the diversity and complexity of effects about stress on different cumulative second harmonics constrain the development of related research. In this paper, a numerical study about the response Law of different cumulative second harmonics with stress is undertaken based on ABAQUS software. A plate finite element model is established and the corresponding simulation experiment is carried out. The simulation result demonstrates that the variation tendencies of different cumulative second harmonic modes with stress are different, and their relative nonlinear parameters are monotonically increasing or decreasing with the increase of tensile stress. Therefore, in the application of stress detection, it is essential to analyze the response law of the selected cumulative second harmonic mode with stress change in advance. The simulation method proposed in this paper is also applicable to other studies about nonlinear ultrasonic waves and has wide applicability.

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Wear Behaviour of Deep Cryogenically Treated Coated Tool During End Milling of Xh67mbtho

SSRN

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SSRN 2024年

作者： Sasi, Jayaram C. Mathew, Jose George, Allan Kuriachen, Basil Dhanish, P.B. Oommen, George Anoop, C.R. Advanced Manufacturing Centre Department of Mechanical Engineering National Institute of Technology Calicut India National Institute of Technology Materials and Manufacturing Entity LPSC Indian Space Research Organisation India Control System and Components Entity LPSC Indian Space Research Organisation India

Current study investigates the influence of deep cryogenic treatment on wear mechanisms across the WC milling inserts while machining XH67MBTHO, a nickel-based superalloy which finds enormous applications in high temperature applications of aerospace engines. With aid of SEM and EDS analysis various mechanism of tool wear including diffusion, abrasion, plastic deformation was studied observed for both cryo treated and untreated tool. A maximum reduction of 26% on flank wear, 48.93% on worn out crater area, 26.97% on resultant cutting force,23.8% on surface roughness was observed while using treated tool in comparison with untreated. © 2024, The Authors. All rights reserved.

关键词： Cryogenics

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An Iterative Method for a Frequency Domain PID controller Synthesis

An Iterative Method for a Frequency Domain PID Controller Sy...

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SICE Annual Conference

作者： Kenjiro Minamikawa Yasushi Kami Eitaku Nobuyama Atsushi Hosokawa Department of Mechanical and Electronic System Engineering Advanced Course of National Institute of Technology Akashi College Hyogo Japan Department of Electrical Systems Engineering Hiroshima Institute of Technology Hiroshima Japan Department of Intelligent and Control Systems Kyushu Institute of Technology Fukuoka Japan Department of Electrical and Computer Engineering National Institute of Technology Akashi College Hyogo Japan

This study is concerned with a control system design method with frequency response data named a finite number of frequency responses(an FNFR) model. In this paper a numerical descent direction is introduced and an iterative method for solving control problems formulated with the FNFR model is proposed with the descent direction. One feature of our approach is to update controller variables so that they approach to a feasible region of considering control problems from the outside. The efficiency of our method is shown by numerical examples.

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Single-grain cutting based modeling of abrasive belt wear in cylindrical grinding

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Friction 2020年第1期8卷 208-220页

作者： Zhe HE Jianyong LI Yueming LIU Jiwang YAN School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Key Laboratory of Vehicle Advanced Manufacturing Measuring and Control TechnologyMinistry of EducationBeijing 100044China Department of Mechanical Engineering Faculty of Science and TechnologyKeio UniversityHiyoshi 3-14-1Kohoku-kuYokohama 223-8522Japan

A systematic wear model of the cylindrical grinding process with an alumina abrasive belt from the perspective of single grain sliding wear was established in this *** model consists of three parts:a single cutting force model derived by applying a stress integration method,a single grain wear height analysis based on the wear rate of alumina,and a grinding mileage prediction of multiple grains with Gaussian distributed protrusion *** force,single grain wear height and full‐size grinding mileage verification experiments were *** results indicated that the established model was in reasonable agreement with the experimental outcomes,which suggests that this model could be useful in the industry to predict the wear process of abrasive belts.

关键词： abrasive belt single grain cutting slide wear grinding mileage

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A Wire-less SiC Power Module Using Flip-Chip Sintering Method

A Wire-less SiC Power Module Using Flip-Chip Sintering Metho...

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International Conference on (ICEPT) Electronic Packaging Technology

作者： Yuncan Liu Haidong Yan Daoguo Yang Wangyun Li Chaohui Liu Yakun Zhang School of Mechanical and Electrical Engineering Guilin University of Electronic Technology Guangxi Key Lab of Manufacturing System and Advanced Manufacturing Technology Guilin China College of Electrical Engineering Zhejiang University Hangzhou China Powertrain Department National New Energy Vehicle Technology Innovation Center (NEVC) Beijing China

As SiC devices move towards lower specific RDS(on) and higher current density, traditional wire bonding SiC power modules are facing serious challenges in thermal management. The top-side of the SiC device of the double-sided cooling (DSC) power module uses a metal surface interconnection instead of the bonding wire point interconnection of the single-sided cooling (SSC) power module, which can effectively improve the current carrying capacity of the devices and significantly reduce the device junction temperature. However, the fragile interconnection structure on the top-side of the SiC devices of the DSC power modules will endure high thermomechanical stress from the upper large-area substrate, leading to significant thermal-mechanical reliability concerns. This paper proposes a flip-chip sintering interconnection method for DSC power modules which strengthens the mechanical interconnection structure between the top-side of the SiC device and the upper substrate. Simultaneously, it further improves the double-sided heat dissipation efficiency and current carrying capacity of the SiC device. Compared with the traditional DSC power modules, the maximum junction temperature of the SiC device of the flip-chip double-sided cooling (FCDSC) power modules is reduced by 14.2%, the effective interconnection area is increased by 60.5%, the maximum thermomechanical stress of the SiC device is reduced by 11.0%, and the maximum current carrying capacity is increased by 5.5%.

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Design and Integration Approach of Low-Inductance Vertical Interconnection Structure for Gallium-Nitride High Electron Mobility Transistors

Design and Integration Approach of Low-Inductance Vertical I...

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International Conference on (ICEPT) Electronic Packaging Technology

作者： Yinxiang Fan Haidong Yan Daoguo Yang Wangyun Li Chaohui Liu Yakun Zhang School of Mechanical and Electrical Engineering Guilin University of Electronic Technology Guangxi Key Lab of Manufacturing System and Advanced Manufacturing Technology Guilin China College of Electrical Engineering Zhejiang University Hangzhou China Powertrain Department National New Energy Vehicle Technology Innovation Center (NEVC) Beijing China

In Gallium-nitride (GaN) high electron mobility transistors (HEMTs) packages, the topside interconnection structures not only play a key role in electrical interconnection but significantly impact the switching performance and heat dissipation efficiency of the dies. Conventional wire bonding technology makes it difficult for GaN HEMT to exploit its potential in high-frequency applications scenarios sufficiently and requires additional package footprint. For the GaN HEMT package, this paper proposes a flip-chip sintering low-inductance interconnection approach based on the DBC/PCB hybrid package structure. The thermal performance and thermal-mechanical reliability of modules under two different processes are evaluated and analyzed through the finite element method (FEM). The results show that the steady-state operation temperature of GaN power modules fabricated by silver sintering is 2.2 °C lower and the maximum thermomechanical stress in the die interconnection layer is 64.9% lower. The optimized gate loop and power loop layouts are analyzed and the power loop inductance is only 0.65 nH. A GaN half-bridge module is fabricated based on this integration scheme, and the static characteristics of the die used for fabrication and the integrated module are compared, and the double-pulse test (DPT) is used to evaluate its switching performance to verify the feasibility of the integration approach.

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The relationship between orthopedic clinical imaging and bone strength prediction

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Medicine in Novel Technology and Devices 2021年第1期9卷 9-17页

作者： He Gong Meng Zhang Shaowei Jia Linwei Lv Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education Beijing Advanced Innovation Center for Biomedical EngineeringSchool of Biological Science and Medical EngineeringBeihang UniversityBeijingChina Department of Engineering Mechanics Nanling CampusJilin UniversityChangchun130025China Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical EngineeringTianjin University of TechnologyTianjin300384China

Pathologic fracture is caused by bone diseases,which is common in middle-aged and elderly *** bone strength is the leading contributor to this type of ***,accurately quantifying bone strength could help clinicians assess individualized fracture risk and develop therapeutic *** clinical imaging including dual X-ray absorptiometry(DXA),computed tomography(CT),and magnetic resonance imaging(MRI)has been an important tool to obtain radiology images of bone,which could be further used for noninvasive assessment of bone strength and related fracture *** the development of biomechanics and computer technology,the combination of finite element analysis with orthopedic imaging is the most advanced method for noninvasive prediction of bone strength in *** this review,an overview is provided for the commonly noninvasive methods based on the radiology images(i.e.,DXA,CT,and MRI)to predict bone strength,which may improve the understanding of the relationship between orthopedic clinical imaging and biomechanics.

关键词： Orthopedic clinical imaging Biomechanics Bone strength Finite element analysis

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