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Accelerated discovery of eutectic compositionally complex alloys by generative machine learning

npj Computational Materials 2024年第1期10卷 1091-1102页

作者： Z.Q.Chen Y.H.Shang X.D.Liu Y.Yang Department of Mechanical Engineering City University of Hong KongHong KongChina City University of Hong Kong(Dongguan) DongguanGuangdongChina College of Mechatronics and Control Engineering Shenzhen UniversityShenzhenChina Department of Materials Science and Engineering City University of Hong KongKowloonChina Department of System Engineering College of EngineeringCity University of Hong KongKowloonChina

Eutectic alloys have garnered significant attention due to their promising mechanical and physical properties,as well as their technological ***,the discovery of eutectic compositionally complex alloys(ECCAs)(*** entropy eutectic alloys)remains a formidable challenge in the vast and intricate compositional space,primarily due to the absence of readily available phase *** address this issue,we have developed an explainable machine learning(ML)framework that integrates conditional variational autoencoder(CVAE)and artificial neutral network(ANN)models,enabling direct generation of *** overcome the prevalent problem of data imbalance encountered in data-driven ECCA design,we have incorporated thermodynamicsderived data descriptors and employed K-means clustering methods for effective data *** our ML framework,we have successfully discovered dual-or even tri-phased ECCAs,spanning from quaternary to senary alloy systems,which have not been previously reported in the *** findings hold great promise and indicate that ourML framework can play a pivotal role in accelerating the discovery of technologically significant ECCAs.

关键词： eutectic alloys alloy

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Modelling and experimental investigation of micro-dimpled structures milling with spiral trajectory tool reciprocating motion

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Chinese Journal of Aeronautics 2025年第2期38卷 577-596页

作者： Guangzhou WANG Linjie ZHAO Qi LIU Xiguang LI Yazhou SUN Mingjun CHEN School of Mechatronics Engineering Harbin Institute of TechnologyHarbin 150001China Centre for Precision Manufacturing DMEMUniversity of StrathclydeGlasgow G11XJUK State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 150001China

To mill fine and well-defined micro-dimpled structures,a machining manner of spiral trajectory tool reciprocating motion,where the tool repeats the process of‘feed milling–retract–cutting feed–feed milling again’along the spiral trajectory,was *** the kinematics analysis,it is found that the machining quality of micro-dimpled structures is highly dependent on the machining trajectory using spiral trajectory tool reciprocating *** reveal this causation,simulation modelling and experimental studies were carried out.A simulation model was developed to quantitatively and qualitatively investigate the influence of the trajectory discretization strategies(constant-angle and constant-arc length)and parameters(discrete angle,discrete arc length,and pitch)on surface texture and residual height of micro-dimpled ***,micro-dimpled structures were milled under different trajectory discretization strategies and parameters with spiral trajectory tool reciprocating motion.A comprehensive comparison between the milled results and simulation analysis was made based on geometry accuracy,surface morphology and surface roughness of milled ***,the errors and factors affecting the above three aspects were *** results demonstrate both the feasibility of the established simulation model and the machining capability of this machining way in milling high-quality micro-dimpled *** trajectory tool reciprocating motion provides a new machining way for milling micro-dimpled structures and micro-dimpled functional *** an appropriate machining trajectory can be generated based on the optimized trajectory parameters,thus contributing to the improvement of machining quality and efficiency.

关键词： Tool reciprocating motion Spiral trajectory Micro-dimpled structure Micromachining Simulation modelling with diamond tool Surface texture

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Tool geometry design and microstructure fabrication by micro flat-end milling on soft-brittle LiF surface

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Journal of Manufacturing Processes 2025年 149卷 868-877页

作者： Lei, Hongqin Zhang, Zixiao Chen, Liang Guo, Yanqiu Cheng, Jian Zhao, Linjie Chen, Mingjun Yang, Dinghuai Chen, Guang State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin 150001 China School of Mechatronics Engineering Harbin Institute of Technology Harbin 150001 China

The LiF crystal with the three-layer step microstructure is vital in the laser-driven quasi-isentropic compression experiment. However, due to the high chemical activity and easy deliquescence of soft-brittle LiF crystals, brittle fracture can easily occur during the microstructure preparation achieved by the micro-milling technology. Therefore, it is essential to determine the optimal tool geometry and preferred processing parameters to achieve an ultra-smooth surface. A finite element (FE) model of the tool geometry optimization for LiF crystals is constructed based on dimensional analysis and the stress-strain curve obtained by nanoindentation tests. Micro-slot and microstructure preparation experiments are conducted to verify the cutting performance of the manufactured cutters with optimal geometry. It is found that the optimal negative rake/relief angles of side- and bottom edges are determined to be −35°/9° and − 25°/20° for tool I from the perspectives of the tensile stress, cutting force, and tool surface stress (σ₁), respectively. For tool II, optimal negative rake/relief angles of the side- and bottom edges are −60°/15° and − 55°/20°, respectively. The σ₁ of tool II is 110.3 MPa, which is 0.74 times and 0.95 times that of tool I (149 MPa) and the CBN tool (116.1 MPa), respectively, indicating that tool II has the most substantial wear resistance under the same processing parameters. Besides, compared with other tool structures, the cutting force and tensile stress are the smallest when using the tool II. The small stress can make the milling process stable, and the vibration and impact generated by the tool are smaller, which helps to make the micro-milled surface smooth. Therefore, the average surface roughness processed by tool II is 0.70 times and 0.47 times that of the CBN tool and tool I, respectively, further illustrating the best cutting performance of tool II. Furthermore, for tool II, the optimal spindle speed and feed per to

关键词： Cutting performance Flat-end milling LiF crystals Microstructure fabrication Tool geometry

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Vehicle Dynamic Model Based Navigation Algorithm Requirement Analysis for Improving High Precision Inertial Navigation system

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Journal of Institute of Control, Robotics and systems 2023年第10期29卷 818-825页

作者： Ko, Bo Sung Kim, Yong Hun Lee, Joo Han Park, So Jin Park, Seung Hyo Song, Jin Woo Department of Intelligent Mechatronics Engineering and Convergence Engineering for Intelligent Drone Sejong University Korea Republic of Naval Combat System PMO Marine Technology Research Institute Agency for Defense Development Korea Republic of

We propose an idea of using VDM (Vehicle Dynamic Model) as a constraint of INS (Inertial Navigation system) for improving the long term navigation performance. In order to suppress long term INS error, a constrained Kalman filter is applied. Before developing the high precision INS with various sensors and techniques, M&S (Modeling & Simulation) step is performed to define and validate the necessary requirements of the development, which here in this research, the requirement of VDM quality is analyzed. M&S is constructed using a 6-DOF submarine dynamic model and a guidance-navigation control model. It is assumed that the navigation sensor is consisted with an inertial measurement unit, EM-Log (Electromagnetic Log), and DM (Depth Module). Monte-Carlo simulation results confirm the effectiveness of the VDM employed by the constrained Kalman filter and requirements for VDM error are also analyzed. © ICROS 2023.

关键词： Inertial navigation systems

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Interference Suppression and Jitter Elimination Ability-Based Adaption Tracking Guidance for Robotic Fishes

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IEEE/CAA Journal of Automatica Sinica 2025年第1期12卷 126-137页

作者： Dongfang Li Jie Huang Rob Law Xin Xu Limin Zhu Edmond Q.Wu IEEE the School of Electrical Engineering and Automation Fuzhou University the Key Laboratory of System Control and Information Processing Ministry of Education the School of Electrical Engineering and Automation Fuzhou University 5G+Industrial Internet Institute Fuzhou University the University of Macau the College of Mechatronics and Automation National University of Defense Technology the School of Mechanical Engineering Shanghai Jiao Tong University the Department of Computer Science and Engineering Shanghai Jiao Tong University

This work presents an adaptive tracking guidance method for robotic fishes. The scheme enables robots to suppress external interference and eliminate motion jitter. An adaptive integral surge line-of-sight guidance rule is designed to eliminate dynamics interference and sideslip issues. Limited-time yaw and surge speed observers are reported to fit disturbance variables in the model. The approximation values can compensate for the system's control input and improve the robots' tracking ***, this work develops a terminal sliding mode controller and third-order differential processor to determine the rotational torque and reduce the robots' run jitter. Then, Lyapunov's theory proves the uniform ultimate boundedness of the proposed method. Simulation and physical experiments confirm that the technology improves the tracking error convergence speed and stability of robotic fishes.

关键词： Adaptive integral surge line-of-sight approximation robotic fish speed observer

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Research on Size Calibration Algorithm of Dark-field Flaw on Optics Surface Based on Convolutional Neural Network

Research on Size Calibration Algorithm of Dark-field Flaw on...

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2024 Applied Optics and Photonics China: Optical Sensing, Imaging Technology, and Applications, AOPC 2024

作者： Wang, Bei Yin, Zhaoyang Zhou, Shicheng Zhao, Linjie Chen, Mingjun Cheng, Jian School of Mechatronics Engineering Harbin Institute of Technology Harbin China State Key Laboratory of Robotics and System Harbin Institute of Technology 150001 China

ISBN: (数字)9781510687820

ISBN: (纸本)9781510687813

Optics in high-power solid-state laser devices will be damaged and adhere to contaminates on the surface during manufacturing and operation, which reduces the service life. To facilitate the positioning and recognition of the flaw (damage and contaminates) in the process of automatic repair, the dark-field flaw size calibration algorithm was studied. In this paper, a flaw size calibration model based on convolutional neural network was established. The size, exposure time, and loss function of damage and contaminate were optimized respectively. The training parameter of the damage regression model is determined to be size of less than 500μm, 30ms of exposure time and SmoothL1 loss function, and the parameter of contaminate is 0-100μm, 20ms of exposure and SmoothL1 loss function. After data balancing, the calibration precision was improved. To improve the calibration consistency of the full-size segment, a comprehensive size calibration strategy is proposed. The CNN regression algorithm is used for small size, and the pixel-level calibration algorithm is used for large size. Compared with the single regression calibration algorithm, the relative error and absolute error of the calibration results of small damage ( © 2024 SPIE.

关键词： Solid state lasers

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Rover Wheel Assistive Grouser Angle of Attack Effects on Traction Force in Soft Terrain 19

Rover Wheel Assistive Grouser Angle of Attack Effects on Tra...

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19th IEEE International Colloquium on Signal Processing and Its Applications, CSPA 2023

作者： Aziz, Intan Nur Aqiella Che Ibrahim, Ahmad Najmuddin Basri, Ikmanizardi Fukuoka, Yasuhiro Universiti Malaysia Pahang Faculty of Manufacturing and Mechatronics Engineering Technology Pahang Malaysia Ibaraki University College of Engineering Department of Mechanical System Engineering Ibaraki Japan

ISBN: (纸本)9781665476928

This paper presents the effects of different grouser angle of attacks on the traction performance of an assistive grouser wheel traversing on soft sandy terrain. This work is an extension from our previous work on assistive grousers attached to a rover wheel to improve performance on soft terrain, where traversing and climbing performance for wheeled rover is improved on steep slopes up to 30-degrees by using assistive grousers rather than conventional fixed grousers. Thus, new experiment correlated with the assistive grouser must be developed for further understanding of the sand-grouser interaction. It was observed that the performance of assistive grousers to reduce sinkage and generate forward traction is influenced by the assistive grousers angle of attack, shape and size. Consequently, for this study we developed a single wheel rover testbed to measure the effects of grouser angle of attack on traction force generated. Grouser attack angles that were experimented are 0,10,20,30 and 40-degrees, on a 0-degree slope sand surface. It was observed that during a grouser's movement, there are instances where a forward and backward traction was generated depending on the position of the grouser during wheel rotation. This was hypothesized to be caused by the imbalance in traction generation by the inner and outer side of the grouser, and also due to the variance in traction force generation by multiple grousers moving under the sand surface at the same time with different speed due to geometric constraints of the assistive grouser horizontal movement. It was concluded that for 0-degree slope, a 0-degree angle of attack is the most effective, and there is considerable effect of using multiple grousers and distance from the wheel on grouser traction generation. Results indicate that the shape of the grouser could increase the effectiveness of the grouser for a future study. © 2023 IEEE.

关键词： Angle of attack

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High accuracy target point classification through dark-field detection of large-aperture optics surface based on machine vision

High accuracy target point classification through dark-field...

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2024 Applied Optics and Photonics China: Optical Sensing, Imaging Technology, and Applications, AOPC 2024

作者： Zhou, Shicheng Yin, Zhaoyang Wang, Bei Zhao, Linjie Cheng, Jian Chen, Mingjun School of Mechatronics Engineering Harbin Institute of Technology Harbin150001 China State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin150001 China

ISBN: (数字)9781510687820

ISBN: (纸本)9781510687813

Surface defects on optics seriously affect their service life in high-power laser system. To address this issue, repair technologies for large-aperture optics are extensively employed. However, the operation of high-power laser system generates a large number of optics requiring repair. Currently, microscopic inspection is widely used for target points classification due to its high accuracy, but it has limitations such as small field of view and low efficiency. Utilizing the OTSU algorithm and Convolutional Neural Networks (CNN), a dark-field classification model for optical surface target points has been developed. Upon conducting experiments with several network models, the ResNet model, a probability threshold of 0.998 were determined. In conclusion, the classification accuracy for defects was 99.18% and for contaminants was 90.34%. The outcomes show that target points on the surfaces of optics can be accurately classified using this method. © 2024 SPIE.

关键词： Machine vision

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Design and Implementation of Automatic Optical Surface Defect Inspection system of Large Aperture Lenses 6

Design and Implementation of Automatic Optical Surface Defec...

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Earth Observing Missions and Sensors: Development, Implementation, and Characterization VI 2024

作者： Tapilouw, Abraham Mario Chang, Yi-Wei Wang, Hau-Wei Chang, Kao-Der Chang, Leh-Rong Chen, Liang-Tang Chen, Chia-Ray Mechanical and Mechatronics Systems Research Labs Industrial Technology Research Institute Taiwan Institute of Space System Engineering National Yang Ming Chiao Tung University Taiwan Taiwan

ISBN: (数字)9781510682771

ISBN: (纸本)9781510682764

Surface quality of optical lenses is an important parameter to achieve optimal imaging quality. Surface imperfections such as scratches, pits, or digs which may be caused during manufacturing or handling induce light scattering and degrade the overall performance of the imaging system. For a lightweight lens, the pockets behind the lens will affect the defect judgment due to excellent optical transmittance. This article discusses the measurement flow of automatic optical inspection for large lenses, defect detection algorithm, and the practicality of application of this technique for inspection of large lenses. Surface defect detection module comprises of high dynamic range camera combined with telecentric imaging lens creating an imaging system with resolution of 2.7 μm. Inspection of the whole surface before and after coating is carried out through concentric scanning and different illustrating angles. The images are captured with a 20% overlap between two consecutive images to ensure complete coverage of the whole surface. Image processing algorithms are applied to detect and classify any surface defects on the surface. Detection results consists of exact size, type, and location of the defects are analyzed by the system and summarized into an inspection report. Compared to classical manual inspection this system provides reproducible and objective detection results and allows users to perform revalidation after measurement is finished. © 2025 SPIE.

关键词： Inspection

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Rational Design of Atomically Immobilized Fe-N4 Sites via Acid-Amine Chemistry:Leveraging Metal Ionic Assistance for Precise Morphology Control

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SusMat 2025年第1期5卷 101-110页

作者： Arunprasath Sathyaseelan Vijayakumar Elumalai Muthukumar Perumalsamy Swapnil Shital Nardekar Arul Saravanan Raaju Sundhar S.C.Karthikeyan Dong Jin Yoo Sang-Jae Kim Nanomaterials&System Laboratory Major of Mechatronics EngineeringFaculty of Applied Energy SystemJeju National UniversityJejuSouth Korea Department of Energy Storage/Conversion Engineering(BK21 FOUR)for Graduate School Hydrogen and Fuel Cell Research CenterJeonbuk National UniversityJeonjuJeollabuk-doSouth Korea Nanomaterials&System Lab Major of Mechanical System EngineeringCollege of EngineeringJeju National UniversityJejuSouth Korea Green Hydrogen Glocal Leading Research Center(gH2-RC) Jeju National UniversityJejuSouth Korea Research Institute of New Energy Industry(RINEI) Jeju National UniversityJejuSouth Korea

Tailoring atomically dispersed single-atom catalyst(Fe-SAC)holding well-defined coordination structure(Fe-N_(4))along with precise control over morphology is a critical ***,we propose a novel acid-amine coupling reaction between metalchelated ionic liquid([1-(3-aminopropyl)3-methylimidazolium tetrachloroferrate(III)][APIM]+[FeCl_(4)]−)and carboxylic groups of carbon allotropes(C=GO,CNT,CNF,and vX-72)to precisely immobilize Fe-N_(x) *** of designed single-atom catalyst(IL-Fe-SAC-C),Fe-N_(4) on graphene(IL-Fe-SAC-Gr)delivered superior oxygen reduction reaction(ORR)activity by holding higher halfwave potential of 0.882 V versus RHE in 1.0 M KOH akin to Pt/C(0.878 V ***)and surpassing recently reported M–N–C catalysts with superior ethanol *** to higher graphitization degree,enhanced surface characteristics,and richness in high-density Fe-N_(4) sites of IL-Fe-SAC-Gr confirmed by XPS,X-ray absorption spectroscopy(XAS),and HAADF *** IL-Fe-SAC-Gr catalyst-coated cathode on testing in flexible direct ethanol fuel cells(f-DEFC)delivered higher peak power density of 18mWcm^(−2) by outperforming Pt/C-based cathode by 3.5 times as a result of excellent ethanol ***,the developed f-DEFCsuccessfully powered the Internet of Things(IoT)-based health monitoring *** method demonstrates novel strategy to tailor high-performance single-atom(Fe-SAC-C)sites on desired morphologies to meet specific application requirements with feasibility and versatility.

关键词： carbon allotropes flexible direct ethanol fuel cells IoT-based health monitoring systems oxygen reduction reaction(ORR) single-atom catalyst

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