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期刊论文 31

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D区 1

RLC网络；谐振性质；振荡特性；幅频特性 1

主动磁悬浮轴承；迭代学习控制；干扰观测器 1

交通导致振动 1

信号平稳化 1

几何学与拓扑学特征 1

分层 1

动、静叶相互作用 1

动力学性质 1

可压缩流 1

叶轮机 1

大桥 1

安全域 1

容错控制；分散式控制；预设性能；无人机；神经网络；干扰观测器；有向拓扑 1

寿命预测 1

小扰动稳定 1

悬索 1

扰动涡方法 1

拉压杆模型 1

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Application of a Novel Fuzzy Clustering Method Based on Chaos Immune Evolutionary Algorithm for Edge Detection in Image Processing

《机械工程前沿（英文）》 2006年第1卷第1期页码 85-89 doi: 10.1007/s11465-005-0023-6

摘要：

A novel fuzzy clustering method based on chaos immune evolutionary algorithm (CIEFCM) is presented to solve fuzzy edge detection problems in image processing. In CIEFCM, a tiny disturbance is added to a filial generation group using a chaos variable and the disturbance amplitude is adjusted step by step, which greatly improves the colony diversity of the immune evolution algorithm (IEA). The experimental results show that the method not only can correctly detect the fuzzy edge and exiguous edge but can evidently improve the searching efficiency of fuzzy clustering algorithm based on IEA.

关键词： disturbance amplitude disturbance diversity generation processing

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Modal disturbance investigation of rod-shaped ultrasonic motor using bending vibrations

ZHANG Jiantao, ZHU Hua, ZHAO Chunsheng

《机械工程前沿（英文）》 2008年第3卷第3期页码 343-347 doi: 10.1007/s11465-008-0058-6

摘要： Modal disturbance of a rod-shaped ultrasonic motor using bending vibrations can cause problems such as low motor efficiency, instability, and poor control. In this paper, a dynamic analysis model of a stator is created on the basis of the finite element method (FEM) and Hamilton principle. The modal frequency sensitivities of the stator to the structure parameters are investigated by modal analysis. Accordingly, the structure parameters of the stator are modified to separate working modes from disturbance modes. A rod-shaped ultrasonic motor stator is fabricated, and the experimental results of its amplitude frequency response characteristics show that the purpose of modal separation is achieved. The frequency separation between working modes and disturbance modes is more than 2 kHz. The validity of the method is verified.

关键词： Hamilton principle disturbance separation frequency separation dynamic analysis

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Virtual reality system of manned maneuvering unit taking into consideration the disturbance from an astronaut

CHENG Jian, FAN Xiu-min, XU An, HONG Xin, HUANG Wei-dong

《机械工程前沿（英文）》 2006年第1卷第3期页码 282-287 doi: 10.1007/s11465-006-0042-y

摘要： This paper describes a manned maneuvering unit (MMU) virtual reality system. Based on the dynamics/kinematics model of an astronaut equipped with an MMU, a disturbance model of the astronaut s arms under zero gravity conditions is developed. After measuring three initial-position information, the astronaut s arms tracking information is inputted by some tracker setting on an operator using real-time emendation and correction. Finally, the paper presents two different results between loading and unloading the disturbance model within the progress of simulation. From the different results, we find that the motion of an astronaut s arms has greater influence over space walking with the same control mode. The MMU virtual reality provides a new method for the simulation of real space walking, and also a perfect method for developing prototype MMU.

关键词： real-time emendation disturbance maneuvering MMU correction

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针对主动磁悬浮轴承干扰抑制的一类结合迭代学习控制与干扰观测器的解决方法 None

Ze-zhi TANG, Yuan-jin YU, Zhen-hong LI, Zheng-tao DING

《信息与电子工程前沿（英文）》 2019年第20卷第1期页码 131-140 doi: 10.1631/FITEE.1800558

摘要：针对主动磁悬浮轴承系统，传统迭代学习控制可实现高精度轨迹跟踪，但系统扰动必须限定为不随迭代变化。基于目前方法，提出一种抑制主动磁悬浮轴承系统中随迭代变化的不匹配扰动方法。在该方案中，结合经典迭代学习控制和普适性扩张观测器，在使用输出反馈信息情况下，可在每次迭代过程中估计并抑制外界变化干扰。分析证明了整个闭环系统的收敛性，同时，仿真结果表明，相比传统迭代学习控制，该控制方法轨迹跟踪性能更加优良。

关键词：主动磁悬浮轴承；迭代学习控制；干扰观测器

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Polycystic ovary syndrome

Zi-Jiang CHEN, Yuhua SHI

《医学前沿（英文）》 2010年第4卷第3期页码 280-284 doi: 10.1007/s11684-010-0098-2

摘要： Polycystic ovary syndrome (PCOS) is a common gynecologic endocrinopathy. The pathogenesis of PCOS is associated with both heredity and environment. PCOS has adverse impacts on female endocrine, reproduction, and metabolism. PCOS can impact women’s reproductive health, leading to anovulatory infertility and higher rate of early pregnancy loss. PCOS has additional metabolic derangements, such as insulin resistance, impaired glucose tolerance, and dyslipidemia. The risks of diabetes, cardiovascular disease, hypertension, metabolic syndrome, and endometrial cancer among PCOS patients are significantly increased as well.

关键词： polycystic ovary syndrome genetics metabolic disturbance

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Research on direct digital process of inductance sensor

WANG Xuan-ze, YANG Lian-gen, ZHONG Yu-ning

《机械工程前沿（英文）》 2006年第1卷第3期页码 317-322 doi: 10.1007/s11465-006-0023-1

摘要： The equivalent circuit of inductance sensor is analyzed. Amplitude-displacement and phase-displacement equations are deduced for non-ideal carrier wave and inductance parameters. Simulation computation shows the corresponding digital curves. Considering that the traditional process method is an approximate one, a new method is presented to simultaneously obtain the amplitude and phase of output signal of sensor by simultaneity A/D and ellipse fit arithmetic. According to the characteristic of the amplitude-displacement and phase-displacement curves, we obtain displacement by phase and amplitude respectively when the sensor is close to the zero point position and away from other positions on the basis of the experiment. The experiment showed that this method can improve precision of measurement, and it can also work for the whole linear range of sensors even if the magnification is very high.

关键词： traditional corresponding phase-displacement Amplitude-displacement characteristic

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用可压缩流涡方法模拟叶轮机动静叶的相互作用

陈矛章,彭波

《中国工程科学》 2000年第2卷第2期页码 15-23

摘要：

本课题组发展了一种扰动涡方法，用以研究叶轮机内动、静叶相互作用^[1，2]。其优点是物理图画清楚，计算收敛快。它采用了一个重要假设：扰动胀量为零，从而大大简化了计算过程。文章的目的是研究此假设的影响，并取消此假设，使扰动涡方法建立在完全严格的数学基础上。由于取消了“扰动胀量为零的假设，需要耦合求解扰动质量方程、扰动涡量输运方程和扰动能量输运方程。这是文章与文献[1，2]的主要区别。

文献[1,2]对NASA67压气机第一级内由于动、静叶间的相互作用引起的非定常流动过程作了数值模拟，并与试验结果作了对比。文章也作了同样的算例，以研究扰动胀量为零的影响。数值模拟结果表明，在引入了扰动胀量后，用扰动涡方法模拟动静干涉仍保持较好的收敛性和收敛速度，且与试验的符合程度更好。文章强调指出，即使对于非定常可压流，为满足无渗透边界条件所需的运动分量也是用椭圆类的拉普拉斯方程描述，而不是用双曲类的方程描述。“扰动胀童为零”不能等同于扰动运动为不可压。

关键词：叶轮机动、静叶相互作用扰动涡方法非定常流可压缩流

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Recognition of diamond grains on surface of fine diamond grinding wheel

HUO Fengwei, JIN Zhuji, KANG Renke, GUO Dongming, YANG Chun

《机械工程前沿（英文）》 2008年第3卷第3期页码 325-331 doi: 10.1007/s11465-008-0071-9

摘要： The accurate evaluation of grinding wheel surface topography, which is necessary for the investigation of the grinding principle, optimism, modeling, and simulation of a grinding process, significantly depends on the accurate recognition of abrasive grains from the measured wheel surface. A detailed analysis of the grain size distribution characteristics and grain profile wavelength of the fine diamond grinding wheel used for ultra-precision grinding is presented. The requirements of the spatial sampling interval and sampling area for instruments to measure the surface topography of a diamond grinding wheel are discussed. To recognize diamond grains, digital filtering is used to eliminate the high frequency disturbance from the measured 3D digital surface of the grinding wheel, the geometric features of diamond grains are then extracted from the filtered 3D digital surface, and a method based on the grain profile frequency characteristics, diamond grain curvature, and distance between two adjacent diamond grains is proposed. A 3D surface profiler based on scanning white light interferometry is used to measure the 3D surface topography of a #3000 mesh resin bonded diamond grinding wheel, and the diamond grains are then recognized from the 3D digital surface. The experimental result shows that the proposed method is reasonable and effective.

关键词： topography frequency disturbance filtering analysis wavelength

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Controlling nested wrinkle morphology through the boundary effect on narrow-band thin films

Hanyang XU, Tielin SHI, Guanglan LIAO, Qi XIA

《机械工程前沿（英文）》 2019年第14卷第2期页码 235-240 doi: 10.1007/s11465-017-0458-6

摘要： We describe the formation of nested wrinkles created by the thermal mismatch between a narrow-band thin film and a compliant substrate. When a film is described as “narrow-band”, it literally means that the film band width is much shorter than its length; more precisely, it means that the width is comparable with the wavelength of the wrinkles. A silicon mask was used during film sputtering to create narrow-band films on poly (dimethylsiloxane) substrate, thus creating regular boundaries to steer local stresses and control wrinkle morphology. Disordered nano-scale wrinkles were found nested within highly ordered micro-scale sinusoidal wrinkles. The formation of nested wrinkles was explained through the amplitude and wavelength saturation of nano-scale wrinkles. The disordered morphology of nano-scale wrinkles and the highly ordered morphology of micro-scale wrinkles were explained by using the boundary effect.

关键词： nested and hierarchical wrinkles morphology amplitude saturation boundary effect

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基于扩展干扰观测器的电液执行器的模糊阻抗控制 Regular Papers-Research Articles

Ming-jie LI, Jian-hua WEI, Jin-hui FANG, Wen-zhuo SHI, Kai GUO

《信息与电子工程前沿（英文）》 2019年第20卷第9期页码 1221-1233 doi: 10.1631/FITEE.1800155

摘要：在本文中，我们同时处理遭受外干扰及参数不确定影响的单出杆电液执行器的速度控制和力控制。在某些应用中，速度控制和力控制两者都有要求。阻抗控制和扩展干扰观测器的结合可以解决该问题。阻抗控制可调节执行器的速度和输出力之间的动态关系，有助于执行器与作用环境或者工件间避免冲击和保持合适的接触力。阻抗规则参数可由模糊算法调节。扩展干扰观测器被用于补偿外部干扰和参数不确定性，实现精确的速度跟踪。为扩展干扰器的开发，提出精确的负载力动力学模型。分析了系统稳定性。实验数据表明所提控制算法具有高精度速度跟踪性能，同时具有良好的力调节能力，在工程机械和装配中具有较大应用前景。

关键词：模糊控制；阻抗控制；干扰观测器；参数不确定性；电液执行器

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Flow behavior of liquid-solid coupled system of piezoelectric micropump

LU Lijun, WU Jiankang

《机械工程前沿（英文）》 2008年第3卷第1期页码 50-54 doi: 10.1007/s11465-008-0003-8

摘要： This paper employs a shallow water model and the finite element method to approximate periodical flows of a micropump to a two-dimensional thickness-averaged flow. A liquid-solid coupled system equation of the micropump is presented. Through the mode analysis of the liquid-solid coupled system, the first-order natural frequency, diaphragm vibration shape and amplitude-frequency relationship are obtained. The vibration response of the diaphragm is calculated when an external electric field is applied. Based on the thickness-averaged flow equation, the periodical flow of the micropump is studied using the finite volume method to investigate the flow behavior and flow rate-frequency characteristics. Numerical results indicate that an optimal working frequency can be obtained, at which the flow rate of the micropump achieves the maximum when the external electric voltage is fixed.

关键词： amplitude-frequency relationship first-order micropump diaphragm vibration electric

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Air-bearing position optimization based on dynamic characteristics of ultra-precision linear stages

CHEN Xuedong, LI Zhixin

《机械工程前沿（英文）》 2008年第3卷第4期页码 400-407 doi: 10.1007/s11465-008-0060-z

摘要： Air-bearings are installed between the stator and the mover of ultra-precision linear stages to suppress vibration and mechanical contact. Spring-damping elements are used to emulate the complex interaction of the finite element model (FEM) developed in this paper and the system dynamic behaviors are analyzed. Through the experimental modal test, the validity and reliability of the model are proven. However, the dynamic characteristics including mode frequency, mode shape, and response amplitude are obviously changed with the position of air-bearings. The combined optimization method is used to optimize the air-bearings position. The best and worst positions are obtained using the dynamic characteristic analysis. The method can be generalized to the connection position of different components in manufacture elements and to implement the system dynamic characteristics optimization when the connection position can be changed.

关键词： manufacture different interaction air-bearings response amplitude

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Model-based nonlinear control of hydraulic servo systems: Challenges, developments and perspectives

Jianyong YAO

《机械工程前沿（英文）》 2018年第13卷第2期页码 179-210 doi: 10.1007/s11465-018-0464-3

摘要：

Hydraulic servo system plays a significant role in industries, and usually acts as a core point in control and power transmission. Although linear theory-based control methods have been well established, advanced controller design methods for hydraulic servo system to achieve high performance is still an unending pursuit along with the development of modern industry. Essential nonlinearity is a unique feature and makes model-based nonlinear control more attractive, due to benefit from prior knowledge of the servo valve controlled hydraulic system. In this paper, a discussion for challenges in model-based nonlinear control, latest developments and brief perspectives of hydraulic servo systems are presented: Modelling uncertainty in hydraulic system is a major challenge, which includes parametric uncertainty and time-varying disturbance; some specific requirements also arise ad hoc difficulties such as nonlinear friction during low velocity tracking, severe disturbance, periodic disturbance, etc.; to handle various challenges, nonlinear solutions including parameter adaptation, nonlinear robust control, state and disturbance observation, backstepping design and so on, are proposed and integrated, theoretical analysis and lots of applications reveal their powerful capability to solve pertinent problems; and at the end, some perspectives and associated research topics (measurement noise, constraints, inner valve dynamics, input nonlinearity, etc.) in nonlinear hydraulic servo control are briefly explored and discussed.

关键词： hydraulic servo system adaptive control robust control nonlinear friction disturbance compensation repetitive control noise alleviation constraint control

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Separation and extraction of bridge dynamic strain data

Baijian WU, Zhaoxia LI, Ying WANG, T. H. T. CHAN,

《结构与土木工程前沿（英文）》 2009年第3卷第4期页码 395-400 doi: 10.1007/s11709-009-0049-7

摘要： Through comparing the measured data of dynamic strains due to loading and temperature by the stain gauge and temperature sensor at the same location, the information in the strain data was divided into three parts in the frequency domain by using the defined index named power spectral density (PSD)-ratio index. The three parts are dominated respectively by temperature varying, stresses, and noises and thus can be distinguished from the determined the separatrix frequencies. Also, a simple algorithm was developed to separate the three types of information and to extract the strain caused mainly by structural stresses. As an application of the proposed method, the effect of strain deformation and noises on the fatigue assessment was investigated based on the separated data. The results show that, the determined values of separatrix frequencies are valuable for the monitoring data from other bridges. The algorithm is a multiresolution and hierarchical method, which has been validated as a simple and effective method for data analyses, and is suitable for the compression and preprocessing of the great amount monitoring data and easy to be integrated into the structural health monitoring (SHM) soft system. The strain due to temperature varying attributes a little to the errors of fatigue assessment; however, the noises or random disturbance existed in the monitoring data have much responsibility for the errors, and the main reason is that the random disturbance shifts the real strain/stress amplitude picked up by real structural stress or strain.

关键词： dynamic valuable separatrix strain/stress amplitude frequency

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High-precision gyro-stabilized control of a gear-driven platform with a floating gear tension device

《机械工程前沿（英文）》 2021年第16卷第3期页码 487-503 doi: 10.1007/s11465-021-0635-5

摘要： This study presents an improved compound control algorithm that substantially enhances the anti-disturbance performance of a gear-drive gyro-stabilized platform with a floating gear tension device. The tension device can provide a self-adjustable preload to eliminate the gap in the meshing process. However, the weaker gear support stiffness and more complex meshing friction are also induced by the tension device, which deteriorates the control accuracy and the ability to keep the aim point of the optical sensors isolated from the platform motion. The modeling and compensation of the induced complex nonlinearities are technically challenging, especially when base motion exists. The aim of this research is to cope with the unmeasured disturbances as well as the uncertainties caused by the base lateral motion. First, the structural properties of the gear transmission and the friction-generating mechanism are analyzed, which classify the disturbances into two categories: Time-invariant and time-varying parts. Then, a proportional-integral controller is designed to eliminate the steady-state error caused by the time-invariant disturbance. A proportional multiple-integral-based state augmented Kalman filter is proposed to estimate and compensate for the time-varying disturbance that can be approximated as a polynomial function. The effectiveness of the proposed compound algorithm is demonstrated by comparative experiments on a gear-drive pointing system with a floating gear tension device, which shows a maximum 76% improvement in stabilization precision.

关键词： inertially stabilized platform floating gear tension device nonlinear friction disturbance compensation proportional multiple-integral observer