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2022 8th International Forum on manufacturing Technology and Engineering Materials, IFEMMT 2022

作者： Zhu, Tongbo Cai, Fan Provincial Key Laboratory of Industrial Robot Measurement and Control Rapid Die Manufacturing Minnan University of Science and Technology Fujian Quanzhou362700 China

Polishing technology is widely used in the polishing process of aspheric optical elements, complex curved surface molds, and so on because of its high machining accuracy, good flexibility, and other advantages. Based on the Preston equation, this paper deduces the material removal function of spherical self-rotating polishing by applying the kinematics principle, obtains the removal function with approximate Gaussian distribution by using computer simulation method, conducts processing technology experiments through the spherical self-rotating polishing device, analyzes the influence of polishing pressure and polishing speed on the polishing removal characteristics of ceramic materials by simulation, and verifies the stability of the removal function through experiments. The results show that the removal function graph is Gaussian distribution, which is conducive to the surface shape convergence of airbag machining. The influence of process parameters on material removal rate is in good agreement with the theory and practice and has a good linear relationship. It is a controllable and deterministic processing mode. © Published under licence by IOP Publishing Ltd.

关键词： Gaussian distribution

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Exploring the nonlinear piezoresistive effect of 4HSiC and developing MEMS pressure sensors for extreme environments

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Microsystems & Nanoengineering 2023年第2期9卷 59-76页

作者： Chen Wu Xudong Fang Qiang Kang Ziyan Fang Junxia Wu Hongtao He Dong Zhang Libo Zha Bian Tian Ryutaro Maedai Zhuangde Jjang State Key Laboratory for Manufacturing Systems Engineering International Joint Laboratory for Micro/Nano Manufacturing and Measurement TechnologiesXian Jiaotong UniversityXian 710049China School of Mechanical Engineering Xian Jiaotong UniversityXi'an 710049China Shandong Laboratory of Yantai Advanced Materials and Green Manufacturing Yantai 265503China Xi'an Jiaotong University(Yantai)Research Institute for Intelligent Sensing Technology and System Xi'an Jiaotong UniversityXianChina HeBei Semiconductor Research Institute Shjiazhuang 050051China

Microelectromechanical system(MEMS)pressure sensors based on silicon are widely used and offer the benefits of miniaturization and high ***,they cannot easily withstand high temperatures exceeding 150 ℃ because of intrinsic material ***,we proposed and executed a systematic and full-process study of Sic-based MEMS pressure sensors that operate stably from-50 to 300 ℃.First,to explore the nonlinear piezoresistive effect,the temperature coefficient of resistance(TCR)values of 4H-SiC piezoresistors were obtained from-50 to 500 ℃.A conductivity variation model based on scattering theory was established to reveal the nonlinear variation ***,a piezoresistive pressure sensor based on 4H-SiC was designed and *** sensor shows good output sensitivity(3.38 mVN/MPa),accuracy(0.56%FS)and low temperature coefficient of sensitivity(TCS)(-0.067%FS/℃)in the range of-50 to 300 ℃.In addition,the survivability of the sensor chip in extreme environments was demonstrated by its anti-corrosion capability in H_(2)SO_(4) and NaOH solutions and its radiation tolerance under 5 W ***,the sensor developed in this work has high potential to measure pressure in high-temperature and extreme environments such as are faced in geothermal energy extraction,deep well dilling,aeroengines and gas turbines.

关键词： environments extreme nonlinear

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An Efficient Distributed Video Compressed Sensing Method 8

An Efficient Distributed Video Compressed Sensing Method

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8th International Conference on Electrical, Mechanical and Computer Engineering, ICEMCE 2024

作者： Lei, Weijie Zhang, Yunze Luo, Xing Peng, Xuqiao Zhao, Jiahong Chen, Shumei Fuzhou University Key Laboratory of Fluid Power and Intelligent Electro-Hydraulic Control Fuzhou University College of Advanced Manufacturing China Fujian Jingong Machinery China

ISBN: (纸本)9798331506230

In recent years, various methods for deep learning techniques for image compressed sensing (CS) have seen rapid advancements, achieving high-quality image reconstruction while maintaining low computational costs. Nevertheless, current deep learning-based image CS techniques primarily concentrate on correlations within frames and often overlook correlations between frames, which leads to inefficiencies when applied directly to video compressed sensing. In this paper, we introduce an effective method for distributed video compressed sensing that aims to leverage both intra- and inter-frame correlations. The proposed distributed video compressed sensing system integrates the benefits of CS with distributed video coding, making it suitable for environments with finite resources for video compression and transmission. However, traditional compressed video sensing (CVS) methods are computationally intensive and time consuming, limiting their real-time applications. We propose a fast CVS reconstruction method based on deep network, named FMCDR-Net. We first perform ISTA-Net++ as the initial reconstruction. The inter-frame reconstruction consists of two stages, where the first stage obtains the initial enhanced reconstructed non-key frames by the designed FMC-Net for motion compensation, and the second stage obtains the final reconstructed non-key frames by the designed FDR-Net for residual reconstruction using the frame difference information in order to recover the details. Experiments manifest that our network performs favorably against similar methods with the better trade-off between parameters and performance. © 2024 IEEE.

关键词： Motion compensation

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Fabrication and characterization of high-sensitivity,wide-range,and flexible MEMS thermal flow velocity sensors

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Microsystems & Nanoengineering 2024年第4期10卷 139-151页

作者： Min Li Guangzhao Qin Chen Jia Danyu Zhang Zhikang Li Xiangguang Han Shusheng Xu Libo Zhao Guoxi Luo Cunlang Liu Ping Yang Qijing Lin State Key Laboratory for Manufacturing Systems Engineering International Joint Laboratory for Micro/Nano Manufacturing and Measurement TechnologiesXi’an Jiaotong University(Yantai)Research Institute for Intelligent Sensing Technology and SystemXi’an Jiaotong UniversityXi’an 710049China School of Instrument Science and Technology Xi’an Jiaotong UniversityXi’an 710049China Shandong Laboratory of Advanced Materials and Green Manufacturing at Yantai Yantai 264000China Brightstone Innovation(Yantai)Research Institute for Micronano Sensing Technology Yantai 264006China Xi’an Jingwei Sensing Technology Co. Ltd.Xi’an 712000China

With the rapid development of various fields,including aerospace,industrial measurement and control,and medical monitoring,the need to quantify flow velocity measurements is *** is difficult for traditional flow velocity sensors to fulfill accuracy requirements for velocity measurements due to their small ranges,susceptibility to environmental impacts,and ***,to optimize sensor performance,a flexible microelectromechanical system(MEMS)thermal flow sensor is proposed that combines the working principles of thermal loss and thermal temperature difference and utilizes a flexible cavity substrate made of a low-thermal-conductivity polyimide/SiO_(2)(PI/SiO_(2))composite porous film to broaden the measurement range and improve the *** measurement results show that the maximum measurable flow velocity can reach 30 m/s with a resolution of 5.4mm/*** average sensitivities of the sensor are 59.49 mV/(m s−1)in the medium-to-low wind velocity range of 0–2 m/s and 467.31 mV/(m s^(−1))in the wind velocity range of 2–30 m/*** sensor proposed in this work can enable new applications of flexible flow sensors and wearable devices.

关键词： flow thermal utilize

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Robustα-Fe_(2)O_(3)/Epoxy Resin Superhydrophobic Coatings for Anti-icing Property

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Journal of Wuhan University of Technology(Materials Science) 2024年第3期39卷 621-626页

作者：乔燕明 TAO Xuan LI Lei 阮敏鲁礼林 College of Chemistry and Chemical Engineering Wuhan University of Science and TechnologyWuhan 430081China Hubei Key Laboratory of Mine Environmental Pollution Control&Remediation and Hubei Engineering Research Center for Collaborative Technology of Advanced Material Manufacturing and Solid Waste Recycling Hubei Polytechnic UniversityHuangshi 435003China

α-Fe_(2)O_(3)/epoxy resin composite superhydrophobic coating was prepared withα-Fe_(2)O_(3) nanoparticles and epoxy resin by spin coating *** coating without epoxy resin has higher contact angle(CA)and lower ice adhesion strength(IAS),but the mechanical properties are ***α-Fe_(2)O_(3)/epoxy resin composite superhydrophobic coating exhibits good mechanical *** addition,compared with the bare aluminum substrate,the Ecorr of the composite coating is positive and the Jcorr is *** inhibition efficiency of the composite coating is as high as 99.98%in 3.5 wt%NaCl *** difference in the microstructure caused by the two preparation methods leads to the changes in mechanical properties and corrosion resistance of composite superhydrophobic coating.

关键词： superhydrophobic anti-corrosion anti-icing robust

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Learning-based tracking control of AUV:Mixed policy improvement and game-based disturbance rejection

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CAAI Transactions on Intelligence Technology 2025年第2期10卷 510-528页

作者： Jun Ye Hongbo Gao Manjiang Hu Yougang Bian Qingjia Cui Xiaohui Qin Rongjun Ding State Key Laboratory of Advanced Design and Manufacturing Technology for Vehicle College of Mechanical and Vehicle EngineeringHunan UniversityChangshaChina School of Information Science and Technology and Institute of Advanced TechnologyUniversity of Science and Technology of ChinaHefeiChina Nanyang Technological University SingaporeSingapore Wuxi Intelligent Control Research Institute of Hunan University Hunan UniversityWuxiChina

A mixed adaptive dynamic programming(ADP)scheme based on zero-sum game theory is developed to address optimal control problems of autonomous underwater vehicle(AUV)systems subject to disturbances and safe *** combining prior dynamic knowledge and actual sampled data,the proposed approach effectively mitigates the defect caused by the inaccurate dynamic model and significantly improves the training speed of the ADP ***,the dataset is enriched with sufficient reference data collected based on a nominal model without considering modelling ***,the control object interacts with the real environment and continuously gathers adequate sampled data in the *** comprehensively leverage the advantages of model-based and model-free methods during training,an adaptive tuning factor is introduced based on the dataset that possesses model-referenced information and conforms to the distribution of the real-world environment,which balances the influence of model-based control law and data-driven policy gradient on the direction of policy *** a result,the proposed approach accelerates the learning speed compared to data-driven methods,concurrently also enhancing the tracking performance in comparison to model-based control ***,the optimal control problem under disturbances is formulated as a zero-sum game,and the actor-critic-disturbance framework is introduced to approximate the optimal control input,cost function,and disturbance policy,***,the convergence property of the proposed algorithm based on the value iteration method is ***,an example of AUV path following based on the improved line-of-sight guidance is presented to demonstrate the effectiveness of the proposed method.

关键词： adaptive dynamic programming autonomous underwater vehicle game theory optimal control reinforcement learning

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Hybrid Decision-making Strategy Combining Reinforcement Learning and Decision Rules for Highway Unmanned Driving

Hybrid Decision-making Strategy Combining Reinforcement Lear...

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2024 IEEE International Conference on Unmanned Systems, ICUS 2024

作者： Zhang, Lele Yang, Zeyu Yu, Caocao Hu, Ziniu Zhou, Yunshui Cui, Qingjia State Key Laboratory of Advanced Design and Manufacturing Technology for Vehicle Hunan University Changsha China Wuxi Intelligent Control Research Institute of Hunan University Wuxi China

ISBN: (纸本)9798350384185

In recent years, reinforcement learning has been employed to address the challenge of unmanned driving decision-making, due to its ability to handle uncertainty and continuous optimization. However, compared with rule-based algorithms, its training time is considerable and the reliability of its results is difficult to guarantee. To enhance the security of decision-making processes, this paper proposes a hybrid decision-making algorithm designed to accelerate the training process of reinforcement learning and enhance the reliability of decision-making. The method first evaluates the confidence levels of both rule-based and learning-based strategies by leveraging the data collected throughout the training phase. Subsequently, an activation function is crafted to determine the final strategy with the greatest level of confidence. This guarantees that the final strategy performs at least on par with the rule-based approach. A simulation focused on highway driving was conducted as a case study to illustrate the effectiveness of the proposed method. The results demonstrate that the proposed approach offers greater profitability than the rule-based method and higher reliability compared to the learning-based method. © 2024 IEEE.

关键词： Reinforcement learning

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advanced liquid crystal-based switchable optical devices for light protection applications:principles and strategies

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Light(Science & Applications) 2023年第4期12卷 512-541页

作者： Ruicong Zhang Zhibo Zhang Jiecai Han Lei Yang Jiajun li Zicheng Song Tianyu Wang Jiaqi Zhu National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin Institute of TechnologyHarbin 150080China Research Center of Analysis and Measurement Harbin Institute of TechnologyHarbin 150080China School of Energy Science&Engineering Harbin Institute of TechnologyHarbin 150001China Key Laboratory of Micro-systems and Micro-structures Manufacturing Ministry of EducationHarbin 150080China

With the development of optical technologies,transparent materials that provide protection from light have received considerable attention from *** important channels for external light,windows play a vital role in the regulation of light in buildings,vehicles,and *** is a need for windows with switchable optical properties to prevent or attenuate damage or interference to the human eye and light-sensitive instruments by inappropriate optical *** this context,liquid crystals(LCs),owing to their rich responsiveness and unique optical properties,have been considered among the best candidates for advanced light protection *** this review,we provide an overview of advances in research on LC-based methods for protection against ***,we introduce the characteristics of different light sources and their protection ***,we introduce several classes of light modulation principles based on liquid crystal materials and demonstrate the feasibility of using them for light *** addition,we discuss current light protection strategies based on liquid crystal materials for different ***,we discuss the problems and shortcomings of current *** propose several suggestions for the development of liquid crystal materials in the field of light protection.

关键词： optical crystal liquid

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A Robust Model Predictive control Method with Output Feedback for Valve-controlled Time-Varying Cylinders System 16th

A Robust Model Predictive Control Method with Output Feedbac...

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16th International Conference on Modelling, Identification and control, ICMIC 2024

作者： Cai, Hui Yan, Hao Shan, Jiefeng Hao, He School of Mechanical Electronic and Control Engineering Beijing Jiaotong University Beijing100044 China Key Laboratory of Vehicle Advanced Manufacturing Measuring and Control Technology Beijing Jiaotong University Ministry of Education Beijing100044 China

ISBN: (纸本)9789819617760

Due to uncertainties in the parameters of the valve-controlled cylinder system and the presence of external disturbances, the force loading performance is compromised, particularly when subjected to extreme conditions involving positional perturbations of the load-bearing system. To tackle this issue, this study presents a robust model predictive control strategy. Initially, a novel linear parameter time-varying system model is developed for precise force loading control of the valve-controlled cylinder, considering both the system's motion characteristics and parameter uncertainties arising from aging and wear. Subsequently, leveraging the proposed robust model predictive controller, we employ linear matrix inequality (LMI) techniques to solve the optimization problem. Through simulation experiments, the effectiveness of the proposed robust control strategy is demonstrated in terms of enhancing force tracking accuracy and ensuring the stability of the force loading system. Additionally, the proposed robust controller exhibits superior performance in attenuating parameter uncertainties and external disturbances. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2025.

关键词： Predictive control systems

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Velocity Constraints Based Approach for Online Trajectory Planning of High‑Speed Parallel Robots

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Chinese Journal of Mechanical Engineering 2022年第6期35卷 98-109页

作者： Di Yang Fugui Xie Xinjun Liu State Key Laboratory of Tribology in Advanced Equipment Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China Beijing Key Lab of Precision/Ultra‑Precision Manufacturing Equipments and Control Tsinghua UniversityBeijing 100084China

High-speed parallel robots have been extensively utilized in the light ***,the influence of the nonlinear dynamic characteristics of high-speed parallel robots on system’s dynamic response and stable operation cannot be ignored during the high-speed reciprocating ***,trajectory planning is essential for efficiency and stability from pick-and-place(PAP)*** paper presents a method for planning the equal-height pick-and-place trajectory considering velocity constraints to improve the PAP efficiency and stability of high-speed parallel *** velocity constraints in the start-and-end points can reduce vibration from picking and placing,making the trajectory more suitable to complex beltline *** on velocity constraints,trajectory optimization includes trajectory smoothness and joint torque to optimize cycle time is carried *** paper proposes an online trajectory optimization *** using back propagation(BP)neural networks,the solution is simplified and can be solved in *** and experiments were carried out on the SR4 parallel *** results show that the proposed method improves the efficiency,smoothness,and stability of the *** paper proposes an online trajectory planning method which is velocity constraints based and can improve the efficiency and stability of high-speed parallel *** work of this research is conducive to finely applying high-speed parallel robots.

关键词： Trajectory planning High-speed parallel robot Velocity constraints BP neural network

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