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New Method to Improve Dynamic Stiffness of Electro-hydraulic Servo systems

Chinese Journal of Mechanical Engineering 2013年第5期26卷 997-1005页

作者： BAI Yanhong QUAN Long Key Laboratory of Advanced Transducers and Intelligent Control System of Ministry of Education Taiyuan University of Technology School of Electronics Information Engineering Taiyuan University of Science and Technology

Most current researches working on improving stiffness focus on the application of control *** controller in closed-loop hydraulic control system takes effect only after the controlled position is deviated,so the control action is *** dynamic performance against force disturbance and dynamic load stiffness can’t be improved evidently by advanced control *** this paper,the elementary principle of maintaining piston position unchanged under sudden external force load change by charging additional oil is *** this basis,the conception of raising dynamic stiffness of electro hydraulic position servo system by flow feedforward compensation is put *** a scheme using double servo valves to realize flow feedforward compensation is presented,in which another fast response servo valve is added to the regular electro hydraulic servo system and specially utilized to compensate the compressed oil volume caused by load impact in *** two valves are arranged in parallel to control the cylinder ***,the model of flow compensation is derived,by which the product of the amplitude and width of the valve’s pulse command signal can be *** determination rules of the amplitude and width of pulse signal are concluded by analysis and *** the proposed scheme,simulations and experiments at different positions with different force changes are *** simulation and experimental results show that the system dynamic performance against load force impact is largely improved with decreased maximal dynamic position deviation and shortened settling *** is,system dynamic load stiffness is evidently *** paper proposes a new method which can effectively improve the dynamic stiffness of electro-hydraulic servo systems.

关键词： electro-hydraulic servo system flow feedforward compensation dynamic load stiffness double-valve actuation

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Fabrication of ordered micro- and nano-scale patterns based on optical discs and nanoimprint

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Optoelectronics Letters 2016年第4期12卷 241-244页

作者：郭慧晶张校亮李晓春 Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of Education and Shanxi ProvinceColleges of Physics and Optoelectronics Taiyuan University of Technology

A simple method to fabricate one-dimensional(1-D) and two-dimensional(2-D) ordered micro- and nano-scale patterns is developed based on the original masters from optical discs, using nanoimprint technology and soft stamps. Polydimethylsiloxane(PDMS) was used to replicate the negative image of the 1-D grating pattern on the masters of CD-R, DVD-R and BD-R optical discs, respectively, and then the 1-D pattern on one of the PDMS stamps was transferred to a blank polycarbonate(PC) substrate by nanoimprint. The 2-D ordered patterns were fabricated by the second imprinting using another PDMS stamp. Different 2-D periodic patterns were obtained depending on the PDMS stamps and the angle between the two times of imprints. This method may provide a way for the fabrication of complex 2-D patterns using simple 1-D masters.

关键词： Compact disks Fabrication Microchannels Nanotechnology Optical data storage Optical disk storage Polydimethylsiloxane Silicones

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Random distributed multi-pulse dynamics in mode-locked regimes of a highly nonlinear fiber ring laser

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Optical Fiber Technology 2025年 93卷

作者： Yueling Hao Lingzhen Yang Juanfen Wang Yuxin Bai Linlin Fan Weijie Ding Shengxiang Chen Jiahao Wang College of Physics and Optoelectronics Taiyuan University of Technology Taiyuan Shanxi 030024 China Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of Education Taiyuan University of Technology Taiyuan Shanxi 030024 China

The generation and transition dynamics of random distributed multi-pulse are studied numerically and experimentally in the mode-locked fiber laser. The influence of various cavity parameters on the generation of multi-pulse in the fiber laser is investigated and the random distributed multi-pulse with delta-like characteristics in the autocorrelation trace is generated numerically. The results show that the highly nonlinear fiber can significantly enhance the nonlinear effect in the cavity to effectively and quickly enter the multi-pulse region. By adding the highly nonlinear fiber to the fiber laser in the experiment, the random distributed multi-pulse is generated under appropriate polarization state and pump power, which is consistent with the simulation results. The transition dynamics of the variation in the number of pulses during the formation process of the random distributed multi-pulse is studied by using the time-stretch dispersive Fourier transform technology. The random distributed multi-pulse combines the advantages of both pulse and chaotic signals, with a higher peak-to-peak value and random distribution in the time interval between pulses. Our work provides fundamental insights into the evolution and dynamic behavior in random distributed multi-pulse and broaden its potential applications in the correlation fiber loop ring down sensing.

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Micro-Mechanism of Silicon-Based Waveguide Surface Smoothing in Hydrogen Annealing

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Chinese Physics Letters 2016年第12期33卷 110-114页

作者：段倩倩任馨宇菅傲群张辉冀健龙张强张文栋桑胜波 Micro Nano System Research Center College of Information EngineeringTaiyuan University of Technology(Ministry of Education)Taiyuan University of Technology Key Laboratory of Advanced Transducers and Intelligent Control System(Ministry of Education) Taiyuan University of Technology

The micro-mechanism of the silicon-based waveguide surface smoothing is investigated systematically to explore the effects of silicon-hydrogen bonds on high-temperature hydrogen annealing waveguides. The effect of silicon- hydrogen bonds on the surface migration movement of silicon atoms and the waveguide surface topography are revealed. The micro-migration from an upper state to a lower state of silicon atoms is driven by silicon- hydrogen bonding, which is the key to ameliorate the rough surface morphology of the silicon-based waveguide. The process of hydrogen annealing is experimentally validated based on the simulated parameters. The surface roughness declines from 1.523nm to 0.461 nm.

关键词： of on Micro-Mechanism of Silicon-Based Waveguide Surface Smoothing in Hydrogen Annealing in is

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Charge transporting materials for perovskite solar cells

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Rare Metals 2021年第10期40卷 2690-2711页

作者： Ting Ji Ying-Kui Wang Lin Feng Guo-Hui Li Wen-Yan Wang Zhan-Feng Li Yu-Ying Hao Yan-Xia Cui College of Physics and Optoelectronics Taiyuan University of TechnologyTaiyuan 030024China Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of Education and Shanxi ProvinceTaiyuan University of TechnologyTaiyuan 030024China

Perovskite solar cells(PSCs) have made great progress since 2009 and become the focus of current research. As an important part of PSCs, charge transporting materials play an important role in the performance of the devices. In this review, we introduce the evolution of electron and hole transporting materials in PSCs in recent years and summarize some typical charge transporting materials and their applications in PSCs. For electron transporting materials, metal oxides(TiO_(2), SnO_(2) and ZnO) and organic materials(fullerenes, non-fullerenes and their derivatives)are the most widely used materials in PSCs. For hole transporting materials, small molecule spiro-OMeTAD(2,2’,7,7’-Tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9’-spirobifluorene), polymer PEDOT:PSS(poly(3,4-ethylenedioxythiophene): polystyrene sulfonate), PTAA(poly-[bi(4-phenyl)](2,4,3-trimethylphenyla-mine)), P3 HT(poly(3-hexythiophene)) and inorganic materials(NiOx, CuSCN, CuO) are adopted in PSCs. Finally, different types of charge transporting materials are summarized and their future development is prospected.

关键词： Perovskite Solar cells Electron transporting materials Hole transporting materials

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Cu/Ag composite nanotrough embedded polyacrylonitrile film: Transparent conducting electrodes with excellent flexibility and a high quality factor

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Organic Electronics 2025年 144卷

作者： Qinjun Sun Jian Zhao Hua Ding Xiaoqian Wang Qianwen Hu LiYan Gao Yuying Hao College of Physics and Optoelectronics Shanxi Key Laboratory of Photovoltaic Technology and Application Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of Education Taiyuan University of Technology Taiyuan 030024 China Graduate School Shanxi Key Laboratory of Photovoltaic Technology Taiyuan University of Technology Taiyuan 030024 China

With high flexibility, conductivity and transparency, metal nanotroughs (NTRs) are considered to be the most promising candidates for flexibility transparent electrode. Here, we report metal NTR films fabricated by electro-spun and thermal evaporation. By optimizing steam treatment time, copper-silver ratio, coverage rate, and transfer process, smooth and continuous metal NTR films were obtained. The Cu/Ag NTR-polyacrylonitrile (PAN) film displayed superior photoelectric properties: transmitted 94.4 % of visible light (550 nm), showed a low sheet resistance of 2.48 Ω/□ and a very high quality factor of 2.27 × 10 −1 (Ω/□) −1 . Meanwhile, the relative change rate of resistance was less than 0.002 under a bending radius of 5 mm after 10,000 cycles. The results indicate that composite metal nanotroughs provide a new way for the preparation of high performance flexible transparent electrode.

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Flow control for a Two-Stage Proportional Valve with Hydraulic Position Feedback

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Chinese Journal of Mechanical Engineering 2020年第6期33卷 64-76页

作者： He Wang Xiaohu Wang Jiahai Huang Long Quan Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of EducationTaiyuan University of TechnologyTaiyuan030024China Shanxi Transportation Technology Research&Development Co. LtdTaiyuan030024China

The current research mainly focuses on the flow control for the two-stage proportional valve with hydraulic position feedback which is named as Valvistor ***,the Valvistor valve is a proportional throttle valve and the flow fluctuates with the change of load *** flow fluctuation severely restricts the application of the Valvistor *** this paper,a novel flow control method the Valvistor valve is provided to suppress the flow fluctuation and develop a high performance proportional flow *** mathematical model of this valve is established and *** proportional-integral-derivative(PID)controller is adopted in the closed-loop flow control *** feedback is obtained by the flow inference with back-propagation neural network(BPNN)based on the spool displacement in the pilot stage and the pressure differential across the main *** results show that inference with BPNN can obtain the flow data fast and *** the flow control method,the flow can keep at the set point when the pressure differential across the main orifice *** flow control method is effective and the Valvistor valve changes from proportional throttle valve to proportional flow *** the developed proportional flow valve,the settling time of the flow is very short when the load pressure changes *** performances of hysteresis,linearity and bandwidth are in a high *** linear mathematical model can be verified and the assumptions in the system modeling is reasonable.

关键词： Flow control Proportional valve Hydraulic position feedback Back-propagation neural network

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A novel fault diagnosis framework for harmonic reducer using transmission error signal

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Measurement 2025年

作者： Runjun Liu Guoyan Li Jingbin Zhang Yongming Zhang Jue Zhang Yiduo Mei Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of Education College of Mechanical Engineering Taiyuan University of Technology Taiyuan 030024 China State Key Laboratory of Intelligent Mining Equipment Technology Shanxi TZ Intelligent Mining Equipment Technology Co.Ltd Taiyuan 030024 China Inspur Yunzhou Industrial Internet Co. Ltd Jinan City Shandong 250101 China

Transmission error (TE) has emerged as a reliable indicator for fault diagnosis. However, in harmonic reducers, the non-stationary nature of measured TE signals results in the coupling of fault information with various interference components, including manufacturing and assembly errors, thereby complicating fault feature identification. To address this issue, this paper first establishes a TE model that accounts for multiple error sources. Simulations of TE under fault conditions reveal that high-frequency components exhibit periodic peaks with distinct fault characteristics, rendering them effective as fault-sensitive features. Building upon the prior analysis, a comprehensive TE-based fault diagnosis framework for harmonic reducers is proposed, termed VMD-DRGAF-Swin Transformer. Initially, the VMD-DRGAF method is proposed for TE signal decomposition and fault feature fusion. This method extracts multi-modal fault-sensitive components and converts them into RGB images. Subsequently, the fused multi-modal images are input into a Swin Transformer-based diagnostic model for fault identification. Finally, an experimental TE signal dataset is collected to validate the diagnostic performance of the proposed method. The results demonstrate that the proposed method achieves higher diagnostic accuracy under various operating conditions, exhibiting strong generalization capabilities. Furthermore, ablation experiments confirm that the VMD-DRGAF method significantly enhances the fault recognition ability and robustness of the diagnostic model, outperforming traditional methods.

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Realizing mode conversion and optical diode effect by coupling photonic crystal waveguides with cavity

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Chinese Physics B 2015年第9期24卷 284-288页

作者：叶寒张金倩楠俞重远王东林陈智辉 State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications Theoretical Condensed Matter Physics and Computational Materials Physics Laboratory School of PhysicsUniversity of Chinese Academy of Sciences Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of Education and Shanxi ProvinceTaiyuan University of Technology

We propose a novel two-dimensional photonic crystal structure consisting of two line defect waveguides and a cavity to realize mode conversion based on the coupling effect. The W1/cavity/W2 structure breaks the spatial symmetry and successfully converts the even（odd） mode to the odd（even） mode in the W2 waveguide during the forward（backward）transmission. When considering the incidence of only the even mode, the optical diode effect emerges and achieves approximate 35 d B unidirectionality at the resonant frequency. Moreover, owing to the narrow bandpass feature and the flexibility of the tuning cavity, utilization of the proposed structure as a wavelength filter is demonstrated in a device with a Y-branch splitter. Here, we provide a heuristic design for a mode converter, optical diode, and wavelength filter derived from the coupling effect between a cavity and adjacent waveguides, and expect that the proposed structure can be applied as a building block in future all-optical integrated circuits.

关键词： mode conversion optical diode photonic crystal

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Study on the High-Speed Penetration and Shear Failure Mechanism of Beach Sand

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Materials 2025年第9期18卷 1922-1922页

作者： Zhu, Jianzhong Li, Jiangquan Kong, Yun Dong, Mingming Li, Yuqiong Zou, Meng Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical Engineering Tianjin University of Technology Tianjin300384 China National Demonstration Center for Experimental Mechanical and Electrical Engineering Education Tianjin University of Technology Tianjin300384 China Key Laboratory for Bionics Engineering of Education Ministry Jilin University Changchun130022 China School of Mechanical Engineering Beijing Institute of Technology Beijing100081 China Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of Mechanics Chinese Academy of Sciences Beijing100190 China State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences Beijing100190 China Guangdong Aerospace Research Academy Nansha Guangzhou511458 China

In this paper, the contact parameters of beach sand are calibrated based on the discrete element method and the optimal design method, and the obtained parameters by calibration are used as input for the angle of repose simulation. The relative error between angle of repose simulation results and experimental results is 3.27%. Based on the penetration and shear tests, simulation models were constructed to study the pressure shear failure mechanism of beach sand under high-speed conditions. The high-speed penetration simulation shows that with the increase of the penetration rate, the influence area of the sinkage plate gradually increases, and the stress of sand particles also increases. When the penetration rate increased from 0.5 m/s to 8 m/s, the pressure on the plate increased 12.7 times, indicating that the bearing capacity of the sand increased significantly with the increase of the penetration rate. The high-speed shear simulation shows that in the stable shear stage, the average shear torque initially increases slightly with the increase of speed, and then decreases significantly when the speed exceeds 4 m/s. This is because as the shear rate increases, the disturbance of the soil by the shear plate increases, the velocity of soil particles increases, resulting in a decrease in the number of soil particles in contact with the shear plate, thereby reducing the shear torque. © 2025 by the authors.

关键词： Fracture mechanics

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