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International Conference on Optical Communications and Networks (ICOCN)

作者： Xiaogang Yi Anbang Wang Tong Zhao Yuncai Wang University of Technology Shanxi Province China Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of Education Shanxi Province Taiyuan

ISBN: (纸本)9781467373746

In this paper, we review the correlation detection technique (CDT) for fiber faults diagnosis and describe our chaotic signal- and communication signal-based correlation detection schemes in passive optical network (PON). The results show that spatial resolution of 2cm and dynamic range of about 20.8dB can be achieved when chaotic signal is used. Utilizing communication signal itself as the probe light, we achieve a spatial resolution of 8cm and detection range of above 23km.

关键词： Correlation Passive optical networks Chaotic communication Optical fibers Spatial resolution

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Dynamic hazard of belt transport tracking and discerning method based on mean shift

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International Journal of Mining and Mineral Engineering 2015年第4期6卷 309-320页

作者： Qiao, Tiezhu Duan, Yanfei Key Lab of Advanced Transducers and Intelligent Control System Ministry of Education and Shanxi Province Taiyuan University of Technology Taiyuan030024 China

For the conveyer belt in coal mine often damaged by hazards such as stones or metals in transit which can cause a longitudinal tear, and the feature of hazards' status changed when transportation belt being torn, a Mean shift tracking and monitoring method was approached. Infrared spectrum imaging model was established for hazard, and extracted hazard grey value according to reflected background radiation differences between hazard and coal in the best wavelength range. Hazard model is established using grey space joint histogram, Mean shift vector is established with bandwidth matrix and recursive equations are given in EM like manner. Experiments show that when hazards tearing the tape, the algorithm can be real-time tracking and monitoring the state of hazards to determine the tape tear. © 2015 Inderscience Enterprises Ltd.

关键词： Image processing

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Characteristics of a Piloted Digital Flow Valve Based on Flow Amplifier

Characteristics of a Piloted Digital Flow Valve Based on Flo...

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2015 International Conference on Fluid Power and Mechatronics

作者： Taotao Li Jiahai Huang Yanhong Bai Long Quan Shengguo Wang Key Lab of Advanced Transducers and Intelligent Control System Ministry of Education and Shanxi ProvinceTaiyuan University of Technology

Hydraulic switching techniques which have less throttling losses, good repeatability and can be controlled intelligently have been largely developed. The biggest challenge is the hydraulic fluctuation. It is generated in the process of opening and closing the valve. A two-stage digital flow valve operated by Pulse Width Modulation(PWM) signal is studied in this paper. The main stage is cartridge valve based on flow amplifying principle;the pilot stage is high-speed on/off valve. The fluctuation characteristic of the digital flow valve is investigated using theoretical derivation and simulation analysis. The results show that the outlet flow fluctuation is influenced by many parameters such as the frequency and duty ratio of PWM signal, the volume of control chamber, etc. It can be weakened through the proper design of these parameters. Although the fluctuation exists, the mean outlet flow can be proportionally controlled by adjustment of the duty ratio of the control signal.

关键词： Flow valve,High-speed on/off valve,PWM,cartridge valve

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Research on the performance of hydraulic excavator with pump and valve combined separate meter in and meter out circuits

Research on the performance of hydraulic excavator with pump...

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International Conference on Fluid Power and Mechatronics (FPM)

作者： Lei Ge Zhixin Dong Weinan Huang Long Quan Jing Yang Wenyong Li Taiyuan University of Technology Key Lab of Advanced Transducers and Intelligent Control System of Ministry of Education Taiyuan China

ISBN: (纸本)9781479987719

Conventional hydraulic actuator is controlled by mechanically connected orifices valve. The controllability of this method is poor and the energy consumption is huge especially under the over-running condition. So a novel system configuration of the hydraulic excavator is presented to improve the problem mentioned above, in which boom cylinder, stick cylinder and swing motor are controlled with separate meter in and meter out technology, bucket cylinder and travel motors are controlled with conventional valves. Firstly, the paper provides a comprehensive review on the development of the separate meter in and meter out technology. Then the principles of load sensing system and SMISMO system applied on the excavator are illustrated though two diagram to show the difference of the two systems. And then a virtual prototype based on the real physical structures is established, which consists of the hydraulic excavator mechanical structure with multi-body dynamics and electro-hydraulic system. The model is verified by the statics and dynamics experiments. Then the dynamic, static performances as well as the energy consumption characteristics of the boom, arm and swing actuators are investigated under the condition of load sensing hydraulic system and the proposed system using the virtual prototype. The control strategy of the actuators is formulated according to their load condition and operation characteristics also based on the detailed analysis. After that, the physical prototype based on the proposed configuration system is established and its performance is tested. The experimental results show that the accuracy of the virtual prototype is validated; the proposed configuration system can significantly decreases the pressure losses through the valve and improve the energy efficiency of the machine; the pressure shocks within hydraulic actuators is decreased as well, thus the stationarity of the whole machine is improved accordingly.

关键词： Valves Actuators Prototypes Energy consumption Cavity resonators Load modeling

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Transient Flow Field Characteristic Analysis of Poppet Valve Based on Dynamic Mesh 6DOF Technique

Transient Flow Field Characteristic Analysis of Poppet Valve...

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2015 International Conference on Fluid Power and Mechatronics

作者： Guo Xiao-xia Huang Jia-hai Quan Long Wang Sheng-guo Key Lab of Advanced Transducers and Intelligent Control System Ministry of Education and Shanxi ProvinceTaiyuan University of Technology

In the fluid engineering, many projects involve movement and deformation of the boundary, but it is difficult to describe them by a simple algebraic expression because the movement of the boundary is determined by the force of hydraulic pressure, torque and other force which work together on the boundary. However, the previous numerical analyses are limited to the steady method or directly giving a speed to the spool which is difficult to actually simulate the movement of the spool. This paper developed a 6DOF model of a threedimensional poppet valve to stimulate the transient flow field in the opening process by means of computational fluid dynamics software—Fluent. The movement of the spool is decided by fluid force which exert on it and its gravity. By comparing numerical simulation results of the valve displacement, pressure of the control chamber and the inlet and outlet flow rate of poppet valve with the experimental results, the numerical results are the same as the experimental results. So the method that the paper proposed is feasible and more truly to simulate the flow state in the opening process of hydraulic valve. And on this basis, the pressure field, velocity field and flow regime are researched when poppet valve reaches steady state, which provides an important theoretical basis for further research on hydraulic valve performance.

关键词： poppet valve numerical calculation Dynamic Mesh Fluent

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Finite Element Analysis of Absorbable Sheath to Prevent Stress Shielding of Tibial Interlocking Intramedullary Nail

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IOP Conference Series: Materials Science and Engineering 2017年第1期224卷

作者： Yansheng Dong Yongqing Wang Limin Dong Peng Jia Fengcheng Lu Tianjin Key Laboratory of the Design and Intelligent Control of the Advanced Mechatronical System School of Mechanical Engineering Tianjin University of Technology Tianjin 300384 China Dept of Orthopaedics the Fourth Central Hospital of Tianjin Tianjin 300140 China Tianjin University of Traditional Chinese Medicine Tianjin 300314 China Dept of Orthopaedics Tianjin Medical University Tianjin 300314 China

The nail with absorbable sheath (AS nail) is designed to reduce the stress shielding effect of internal fixation with interlocking intramedullary nail. In order to verify its feasibility, two types of the finite element models of internal fixation of tibia with the AS nail and the common metal nail (CM nail) are established using the Softwares of Mimics, Geomagic, SolidWorks and ANSYS according to the CT scanning data of tibia. The result of the finite element analysis shows that the AS nail has great advantages compared with the CM nail in reducing the stress shielding effect in different periods of fracture healing. The conclusion is that the AS nail can realize the static fixation to the dynamic fixation from the early to the later automatically to shorten the time of fracture healing, which also provides a new technique to the interlocking intramedullary nail.

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Study on Resonant Characteristics for Higher-Order Modes in Zero Index Metamaterials Loaded with Dielectric Rings

Study on Resonant Characteristics for Higher-Order Modes in ...

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Asia-Pacific Microwave Conference

作者： Binzhao Cao Wenjuan Liang Shuxian Li College of Physics and Optoelectronics Taiyuan University of technology/Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of Education School of Information Science and Engineering Lanzhou University

ISBN: (纸本)9781479987689

The transmission characteristics of electromagnetic wave in the parallel planar waveguide system filled with zero index metamaterials, in which embedded with dielectric rings, is improved based on the general theoretical analysis. We conceive that higher-order modes can be produced in the dielectric rings under the isotropic medium of zero index metamaterials, and also analyze the condition of producing high order modes and the resonance characteristics for several of the whispering gallery mode (WGM). The theoretical results are simulated by COMSOL and its correctness is verified. The conclusion of this paper has important application value in the manipulation of electromagnetic waves, power allocation and sensing, so on.

关键词： Electromagnetic scattering Indexes Metamaterials Dielectrics Electromagnetics Planar waveguides

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Chaotic light generation and its application in communication, sensor, radar

Chaotic light generation and its application in communicatio...

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International Conference on Optical Communications and Networks (ICOCN)

作者： Mingjiang Zhang Anbang Wang Yuncai Wang Key Lab of Advanced Transducers and Intelligent Control System Ministry of Education and Shanxi Province Taiyuan University of Technology Taiyuan Shanxi CN

Chaotic light has aroused considerable interest owing to its wide applications. Semiconductor laser, subject to optical feedback, optical injection, or optoelectronic feedback, can readily emit large-amplitude optical chaotic signals, and hence become the most suitable chaotic light sources. This paper illustrates the chaotic light generation based on semiconductor laser and its application in optical time domain reflectometry, distributed fiber sensing and photonic UWB radar.

关键词： Chaotic communication Optical feedback Optical fibers Optical attenuators Optical fiber sensors Optical reflection

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Compensation of friction and elastic deformation for ball screw drive system

Compensation of friction and elastic deformation for ball sc...

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IEEE International Conference on Mechatronics and Automation

作者： Hongbiao Xiang Shoujun Wang Chunqiu Zhang Xingfei Li Jun Liu Tianjin Key Laboratory of the Design and Intelligent Control of the Advanced Mechatronical System Tianjin University of Technology Tianjin CN Tianjin Key Laboratory of the Design and Intelligent Control of the Advanced Mechatronical System Tianjin University Tianjin Tianjin CN

Nonlinear friction and elastic deformation seriously affect both static and dynamic performance of mechanical serve system, especially in the high-speed and high-precision systems. This paper focuses on modeling, identification, and compensation of non-linear friction and elastic deformation for ball screw drive system. Firstly, the parameters of the stribeck model are identified by the method of extended kalman filter. And then the parameters of stiffness model of the ball screw are identified by the method of the least square based on force analysis of system. Finally, the feed-forward compensation of friction and elastic deformation is performed. The experimental results show that: after the compensation, the steady state error of low-speed motion decreases from 42μm to ±3μm, and that of high-speed motion decreases from 95μm to ±5μm. Therefore, the method proposed can effectively compensate the disturbance of friction and elastic deformation, and improve the tracking accuracy of the ball screw drive system.

关键词： Friction Fasteners Mathematical model Servomotors Deformable models Tracking Force

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Design of dual-frequency bioreactor control system

Design of dual-frequency bioreactor control system

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IEEE International Conference on Mechatronics and Automation

According to tissue engineering and basic principle of bionic, the low-frequency high-amplitude loading on articular cartilage is to simulate human walking or other activities, and the high-frequency low-amplitude loading is to maintain the cartilage framework structure from muscles, ligaments and other tissue. In order to build appropriate mechanical environment for cartilage tissue engineering, this paper design a dual-frequency bioreactor, and the control precision and performance is improved by a method of friction compensation. The control system is full closed loop composed of liner motor and grating scale, based on PC+PMAC opened control platform. Firstly, a dynamic equation of an open servo system is given and the friction characteristics are described based on Stribeck model. Secondly, Considering the parameters of friction model changed with the system, the controller of adaptive sliding friction compensation is designed by backstepping method, and the corresponding adaptive laws and switching functions are given. Besides, this method give analysis of its global asymptotic stability, proved by Lyapunov theorem. Finally, the adaptive sliding friction compensation control strategy is realized by Programmable Multi-Axis controller (PMAC), and the effectiveness of the method is verified by experiments. Results show that the steady state error of sinusoidal motion is decreased from the ± 22μm to ± 4μm compared with the velocity and acceleration forward feed-compensation. The dual-frequency bioreactor can simulate the mechanical environment of artificial cartilage tissue engineering on micrometer level, furthermore, it laid a foundation for the research of mechanobiology of cartilage.

关键词： Friction Mathematical model Tissue engineering Loading Adaptation models Servomotors

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