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Digital twin modeling of the robotic gluing system for predicting the quality of glue lines and optimizing gluing parameters

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Journal of Manufacturing systems 2025年 80卷 1074-1092页

作者： Kang, Ruihao Hu, Junshan Li, Mingyu Zhang, Qi Su, Xingtao Li, Zhengping Tian, Wei College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and Astronautics Nanjing210016 China State Key Laboratory of Intelligent Manufacturing System Technology Beijing100854 China

Digital twin (DT) technology is changing the current pattern of intelligent manufacturing, it makes up for the shortcomings of process parameter optimization methods to improve real-time and predictability. This paper developed DT models for the robotic gluing system to predict the quality (width and thickness) of glue lines and optimize gluing parameters (trajectory and extrusion speeds). The DT framework based on the geometric, physical, behavioral, and rule models is constructed to monitor and optimize the gluing parameters in real-time. An improved backpropagation neural network (BPNN) prediction model based on whale optimization algorithm (WOA) is established to predict the width and thickness of glue lines from historical and real-time data, while simultaneously enabling real-time calculation of the cross-sectional area of glue lines. A multi-objective optimization model constructed using non-dominated sorting genetic algorithm (NSGA-II) is used to optimize the gluing parameters. The DT prototype of the robotic gluing system has been developed and verified experimentally. The position calibration of the geometric model is used to correct the gluing trajectory before gluing, and the position errors of the gluing points are within ± 0.5 mm. The gluing trajectory is designed to test the effectiveness of the adaptive optimization of gluing parameters. The prediction errors of the width and thickness of the glue line are controlled between ± 0.5 mm and ± 0.3 mm, individually. After parameter optimization, the width and thickness of the glue line at the corner are reduced by 4.53 % and 7.54 %, respectively, thus avoiding glue accumulation. This reduction solves the problem of poor consistency in the quality of glue lines and verifies the feasibility of integrated monitoring, prediction, and optimization based on the DT model. © 2025 The Society of Manufacturing Engineers

关键词： Genetic algorithms

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Development of a high-performance bend-actuated piezoelectric tip/tilt stage with low power and simple operation

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Science China Technological Sciences 2025年第6期 234-245页

作者： Jinghan GUAN Shijing ZHANG Jie DENG Weishan CHEN Junkao LIU Yingxiang LIU State Key Laboratory of Robotics and System Harbin Institute of Technology

Piezoelectric tip/tilt stages(PZT stages), which precisely and quickly control laser beam deflection, are widely used in laser communications. Most are driven by piezoelectric stack actuators(PSAs) and have high capacitance and power consumption. The negative voltage causes irreversible damage to PSAs. Therefore, negative voltage operation needs to be prohibited, which complicates manipulating the bidirectional deflection of the mirror. However, the aerospace field places higher requirements on power consumption and ease of operation, which makes the PZT stage require reduced power consumption and simple operation. This paper presents a high-performance bend-actuated PZT stage, which uses ceramic plates for driving, with a capacitance of only 26.4 nF/axis and a power of only 27 mW(at operating conditions of 1 mrad and 100 Hz).The sandwich structure allows for bi-directional voltage, which makes the operation easier. Two channels control two degrees of freedom(DOFs). A theoretical model suitable for bend-actuated structures is proposed. It is used to calculate the deflection angle and resonance frequency, and its validity is verified by finite element analysis. Experimental results show that it has a deflection angle of ±2.97 mrad(x-axis), ±3.24 mrad(y-axis) at 600 V p-p, an unloaded first-order resonance frequency of 1728 Hz, and a quasi-static hysteresis of only 7.5%, which is less than that of PSAs(>10%). With the constructed laser beam deflection system, a circular trajectory is realized, which has the potential for beam steering.

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Realizing high-speed target tracking by using multi-rate feedforward predictive control for the acquisition, tracking, and pointing system

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Defence technology 2025年

作者： Li, Hang Peng, Gaoliang Shan, Xiaobiao Zhao, Mingyuan Zhang, Wei Wang, Jinghan Cheng, Feng State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin150001 China College of Information Science and Technology Eastern Institute of Technology Ningbo315200 China

The acquisition, tracking, and pointing (ATP) system is widely used in target tracking, counter-UAV operations, and other related fields. As UAV technology develops, there is a growing demand to enhance the tracking capabilities of ATP systems. However, in practical applications, ATP systems face various design constraints and functional limitations, making it infeasible to indefinitely improve hardware performance to meet tracking requirements. As a result, tracking algorithms are required to execute increasingly complex tasks. This study introduces a multi-rate feedforward predictive controller to address issues such as low image feedback frequency and significant delays in ATP systems, which lead to tracking jitter, poor tracking performance, low precision, and target loss. At the same time, the proposed approach aims to improve the tracking capabilities of ATP systems for high-speed and highly maneuverable targets under conditions of low sampling feedback rates and high feedback delays. The method suggested is also characterized by its low order, fast response, and robustness to model parameter variations. In this study, an actual ATP system is built for target tracking test, and the proposed algorithm is fully validated in terms of simulation and actual system application verification. Results from both simulations and experiments demonstrate that the method effectively compensates for delays and low sampling rates. For targets with relative angular velocities ranging from 0 to 90°/s and angular accelerations between 0 and 470°/s2, the system improved tracking accuracy by 70.0%–89.9% at a sampling frequency of 50 Hz and a delay of 30 m s. Moreover, the compensation algorithm demonstrated consistent performance across actuators with varying characteristics, further confirming its robustness to model insensitivity. In summary, the proposed algorithm considerably enhances the tracking accuracy and capability of ATP systems for high-speed and highly maneuverable ta

关键词： Predictive control systems

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Performance assessment of octagonal layout based integrated photonic reservoir computing for optical channel equalization

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Optics Express 2025年第7期33卷 15814-15826页

作者： Zuo, Xiaoyan Pei, Li Bai, Bing Bai, Bowen Hu, Zhouyi Wang, Jianshuai Qu, Qi Dong, Fei Institute of Lightwave Technology Beijing Jiaotong University Ministry of Education Key Laboratory of All-Optical Networks and Modern Communication Networks Beijing100044 China Technology Co. Ltd. China State Key Laboratory of Advanced Optical Communications System and Networks School of Electronics Peking University Beijing100871 China Beijing Aerospace Institute for Metrology and Measurement Technology Beijing100076 China

Compared to electronic equalizers, the equalizers based on integrated photonic reservoir computing exhibit the advantages of large bandwidth, short latency, and low power consumption. The existing rectangular reservoir layout employs internal nodes as input and output nodes, leading to inadequate signal exchange and extra noise due to waveguide crossing. We proposed an optical channel equalizer based on an octagonal reservoir layout and verified its equalization ability. The system-level simulation of the proposed layout is conducted to investigate the impact of layout shape, node quantity, input and output port number, and weight algorithm on channel equalization performance in a 25Gbaud 4-level pulse amplitude modulation optical communication system. Results indicate that, within a transmission distance of 5-30 km, the bit error rate (BER) of the equalized signal in the proposed octagonal layout is lower than that of a rectangular layout with the same number of nodes. Specifically, at 5 km, the octagonal layout’s BER is 5 and 10 orders of magnitude lower than the rectangular layout and the feedforward equalizer, respectively. Meanwhile, the best readout algorithm, K-nearest neighbor regression, achieves an equalized BER of 7.012 × 10−14 © 2025 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement.

关键词： Pulse amplitude modulation

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Effects of visual rotation axis and clockwise/counterclockwise directions on circular vection in virtual reality 24

Effects of visual rotation axis and clockwise/counterclockwi...

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2024 International Conference on Virtual Reality, Image and Signal Processing, ICVISP 2024

作者： Xu, Xiaotian Song, Zhe Zhang, Kexin Xu, Yan Zhang, Yuankun Fan, Xiaoya Pu, Fang Key Laboratory of Human Motion Analysis and Rehabilitation Technology of the Ministry of Civil Affairs Beihang University Beijing China Key Laboratory for Ubiquitous Network and Service Software of Liaoning Province Dalian University of Technology Liaoning Dalian China State Key Laboratory of Virtual Reality Technology and System Beihang University Beijing China

ISBN: (纸本)9798400710926

Vection, an illusion of self-motion induced by visual stimulus frequently experienced in virtual reality, significantly impacts user experiences in gaming, driving simulation, and rehabilitation training. User often experience circular vection, an illusion of self-rotation. However, the effects of visual rotation axes and rotation directions on circular vection remain elusive. We employ a 3 (rotation axis: sagittal, coronal, vertical) × 2 (rotation direction: clockwise, counterclockwise) repeated-measures design. Twenty participants were recruited. They were exposed to a virtual visual rotating drum at 60 °/s to induce circular vection. The real-time estimation of perceived self-motion rotation velocity (PSRV) was obtained. Results indicated that during the 30-second constant rotation, the group-level PSRV showed an initial rapid increase followed by a slower rise. A significant interaction effect between rotation axis and direction was revealed. The rotation direction showed no significant effect on PSRV under sagittal and vertical conditions. However, under coronal condition, the PSRV was significantly higher when rotating counterclockwise, compared to rotation clockwise. In addition, when rotating counterclockwise, the highest PSRV appeared under sagittal condition, with the lowest under the coronal condition and the middle under the vertical condition. These findings provide valuable insights for designing VR scenarios with better user experience by vection manipulation. © 2024 Copyright held by the owner/author(s).

关键词： Virtual reality

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Dynamic Response Characteristics of Multi-Generation system Integrated with Gas and Heat Storage

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Journal of Thermal Science 2025年第3期34卷 913-935页

作者： WANG Xiaomeng DUAN Liqiang ZHENG Nan WANG Qiushi Beijing Laboratory of New Energy Storage Technology North China Electric Power University School of Energy Power and Mechanical Engineering North China Electric Power University State Key Laboratory of Alternate Electric Power System with Renewable Energy Sources (NCEPU) North China Electric Power University Institute of Technology for Carbon Neutralization College of ElectricalEnergy and Power EngineeringYangzhou University

In this paper,a new multi-generation system,incorporating solid oxide fuel cell(SOFC),gas turbine(GT),lithium bromide chiller,gas and heat storage components is proposed to address the issues of volatility in user load and energy source input and mismatching between supply and *** dynamic model and control strategy of the system are established,and the system dynamic characteristics in response to solar DNI and external load disturbances are *** system can rapidly adjust the key output and input parameters to realize a new supply-demand balance in a shorter period of time by multiple PID control *** response processes of two combined cooling,heating and power(CCHP) systems with and without gas storage to cope with load changes are *** results show that the CCHP system with gas storage can effectively shorten the response time of load *** solar collector and the SOFC-GT can reach a new equilibrium within a few tens of seconds under the *** response time of the methanol reactor is longer compared to those of solar collector and the SOFC-GT,taking several minutes to *** the cooling and heating load change,the system can adjust the output to the demand value within 500 and 260 seconds.

关键词： dynamic analysis energy storage load-following methanol to hydrogen multi-generation system

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Investigation on influence of gamma irradiation on piezoelectric and resonance characteristics of surface acoustic wave resonators 5

Investigation on influence of gamma irradiation on piezoelec...

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5th International Conference on Mechanical Engineering and Materials, ICMEM 2024

作者： Sun, Lei Peng, Bin Yang, Yuntao Sun, Zhaofeng Zhu, Jialiang Zhang, Wanli State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of China Chengdu China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of China Chengdu China

ISBN: (数字)9781510688971

ISBN: (纸本)9781510688964

In this work, an evaluation towards influence of high-dose gamma irradiation on surface acoustic wave (SAW) resonators, is reported. The single-port SAW resonators are fabricated using Lithium niobate (LiNbO3) and Catangasite (CTGS, Ca3TaGa3Si2O14) substrates, along respective cut directions of (0º, 38º, 0º) and (0º, 90º, 0º). Piezoelectric coefficient of substrates, and several main resonance parameters covering resonance frequency, amplitude of resonance peak in reflection coefficient, quality factor together with electromechanical coupling factor of manufactured SAW resonators are investigated, as suitable representatives of piezoelectric and resonance characteristics of SAW resonators. After exposure to gamma ray with a maximum dose of 250 kGy, substrates show insignificant variation not exceeding 6% in their piezoelectric coefficient. Meanwhile, resonance parameters of SAW resonators also alter slightly. Such excellent stability of these characteristics demonstrates credible irradiation hardness owned by both SAW resonators. Results in this study can provide supportive references for usage of LiNbO3 and CTGS-based SAW devices in harsh environments. © 2025 SPIE.

关键词： Gamma rays

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A Cost-Sensitive Multi-scale Feature Multi-order Fusion Network for Bearing Fault Diagnosis Under Data Imbalance Conditions

A Cost-Sensitive Multi-scale Feature Multi-order Fusion Netw...

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International Conference on Artificial Intelligence and Autonomous Transportation, AIAT 2024

作者： Deng, Shuaiqing Lei, Zihao Wen, Guangrui Su, Yu Liu, Zimin Meng, Zhangxuan Zhang, Zhifen National Key Laboratory of Aviation Power System and Plasma Technology Xi’an Jiaotong University Xi’an710049 China State Key Laboratory for Manufacturing Systems Engineering Xi’an Jiaotong University Xi’an710049 China Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing System Xi’an Jiaotong University Xi’an710049 China

ISBN: (纸本)9789819639724

Railroad transportation plays a vital role in the national economy, and fault diagnosis of its key components is of great significance in ensuring its safe operation. However, due to its long-term operation in a healthy state, it is tough to obtain fault signals, and this class imbalance data seriously degrades the diagnostic capability of intelligent diagnostic algorithms, leading to increased misclassification of minority classes. To address this problem, we propose a cost-sensitive multi-scale feature multi-order fusion network for bearing fault diagnosis under data imbalance conditions. Firstly, a lightweight multi-scale convolutional layer is employed to effectively extract the multi-scale features of the signal. Then the multi-order feature fusion is performed by a hornet to fully utilize the multi-scale information and enhance the ability to mine the limited diagnostic information of the minority class. And the excellent high-dimensional discriminative features are extracted through residual blocks. In addition, an improved cost-sensitive strategy is designed through the posterior probability distribution to rebalance the contribution of each class to the training process for improving the overall diagnostic performance of the model. Finally, the effectiveness and superiority of the proposed method are comprehensively verified by several sets of experiments with different imbalance rates. © Beijing Paike Culture Commu. Co., Ltd. 2025.

关键词： Railroad transportation

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Loaded tooth contact analysis and meshing stiffness calculation for cracked spiral bevel gears

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Chinese Journal of Aeronautics 2025年第3期38卷 593-623页

作者： Zhen LIU Fucai LI Wenjie BAO Xiaolei XU Freeda A.AMIR State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China School of Mechatronic Engineering China University of Mining and TechnologyXuzhou 221116China Jiangsu JITRI Composite Equipment Research Institute Co. Ltd.Wuxi 214000China

Tooth cracks may occur in spiral bevel gear transmission system of the aerospace *** this study,an accurate and efficient loaded tooth contact analysis(LTCA)model is developed to predict the contact behavior and time-varying meshing stiffness(TVMS)of spiral bevel gear pair with cracked *** tooth is sliced,and the contact points on slices are computed using roll angle *** the geometric complexity of crack surface,a set of procedures is formulated to generate spatial crack and determine crack parameters for contact *** to the positional relationship between contact point and crack path,each sliced tooth is modeled as a non-uniform cantilever beam with varying reduced effective load-bearing tooth *** the compliance model of the cracked tooth is established to perform contact analysis,along with TVMS calculations utilizing three different *** employing spiral bevel gear pairs with distinct types of cracks as examples,the accuracy and efficiency of the developed approach are validated via comparative analyses with finite element analysis(FEA)***,the investigation on effects of cracks shows that tooth cracks can induce alterations in meshing performance of both entire gear pair and individual tooth pairs,including not only cracked tooth pair but also adjacent non-cracked tooth ***,the proposed model can serve as a useful tool for analyzing the variations in contact behavior and meshing stiffness of spiral bevel gears due to different cracks.

关键词： Bevel gears Gear teeth Cracks Loaded tooth contact analysis Time-varying meshing stiffness Tooth compliance

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A multi-channel image-based method for flight delay prediction in terminal area 4

A multi-channel image-based method for flight delay predicti...

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2024 4th International Conference on Intelligent Traffic systems and Smart City, ITSSC 2024

作者： Yang, Yihan Chen, Haiyan Yang, Longwu State Key Laboratory of Air Traffic Management System Nanjing China College of Computer Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing China

ISBN: (纸本)9781510686304

With the rapid development of civil aviation, flight delays have become increasingly critical. Effectively predicting flight delays has become a research hotspot in recent years. In this paper, we propose a novel flight delay prediction method based on image recognition by applying deep learning techniques. We first rasterize the target terminal area into a grid image of size 25×25. Then, we convert the arrival and departure traffic flow data collected over some time into colors and fill them into the corresponding grids to obtain the arrival and departure traffic flow images. On this basis, we design the prediction model Attention-Complementary Hybrid Network (ACHNet), which can be used for multi-channel image feature fusion. It takes arrival and departure traffic flow images as inputs and fuses the spatial information of these two types of images through the fusion branch. We use the Convolutional Neural Network (CNN)-based prediction model to predict flight delays on arrival and departure traffic flow image sets respectively, and compare the prediction results with those of ACHNet. The experimental results show that the fusion of multi-channel image features can effectively improve the performance of flight delay prediction. © 2025 SPIE.

关键词： Convolutional neural networks

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