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Nonlinear dynamic analysis for elastic robotic arms

H. KORAYEM, H. N. RAHIMI

《机械工程前沿（英文）》
2011年
第6卷
第2期
页码 219-228
*doi:*
*10.1007/s11465-011-0218-y*

摘要：

The aim of the paper is to analyze the nonlinear dynamics of robotic arms with elastic links and joints. The main contribution of the paper is the comparative assessment of assumed modes and finite element methods as more convenient approaches for computing the nonlinear dynamic of robotic systems. Numerical simulations comprising both methods are carried out and results are discussed. Hence, advantages and disadvantages of each method are illustrated. Then, adding the joint flexibility to the system is dealt with and the obtained model is demonstrated. Finally, a brief description of the optimal motion generation is presented and the simulation is carried out to investigate the role of robot dynamic modeling in the control of robots.

关键词： robotic arms elastic link elastic joint nonlinear dynamics optimal control

H_{∞} control in the frequency domain for a semi-active floor isolation system

Yundong SHI, Tracy C BECKER, Masahiro KURATA, Masayoshi NAKASHIMA

《结构与土木工程前沿（英文）》
2013年
第7卷
第3期
页码 264-275
*doi:*
*10.1007/s11709-013-0214-x*

摘要：
A floor isolation system installed in a single floor or room in a fixed base structure is designed to protect equipment. With this configuration, the input motions to the floor isolation from the ground motions are filtered by the structure, leaving the majority of the frequency content of the input motion lower than the predominant frequency of the structure. The floor isolation system should minimize the acceleration to protect equipment; however, displacement must also be limited to save floor space, especially with long period motion. Semi-active control with an control was adopted for the floor isolation system and a new input shaping filter was developed to account for the input motion characteristics and enhance the effectiveness of the control. A series of shake table tests for a semi-active floor isolation system using rolling pendulum isolators and a magnetic-rheological damper were performed to validate the control. Passive control using an oil damper was also tested for comparison. The test results show that the control effectively reduced acceleration for short period motions with frequencies close to the predominant frequency of the structure, as well as effectively reduced displacement for long period motions with frequencies close to the natural frequency of the floor isolation system. The control algorithm proved to be more advantageous than passive control because of its capacity to adjust control strategies according to the different motion frequency characteristics.

关键词：
semi-active
floor isolation
_{∞} control
MR damper
shaping filter
shaking table test

NAZEMIZADEH, H. N. RAHIMI, K. AMINI KHOIY

《机械工程前沿（英文）》
2012年
第7卷
第1期
页码 23-28
*doi:*
*10.1007/s11465-012-0304-9*

摘要：

This paper presents an optimal control strategy for optimal trajectory planning of mobile robots by considering nonlinear dynamic model and nonholonomic constraints of the system. The nonholonomic constraints of the system are introduced by a nonintegrable set of differential equations which represent kinematic restriction on the motion. The Lagrange’s principle is employed to derive the nonlinear equations of the system. Then, the optimal path planning of the mobile robot is formulated as an optimal control problem. To set up the problem, the nonlinear equations of the system are assumed as constraints, and a minimum energy objective function is defined. To solve the problem, an indirect solution of the optimal control method is employed, and conditions of the optimality derived as a set of coupled nonlinear differential equations. The optimality equations are solved numerically, and various simulations are performed for a nonholonomic mobile robot to illustrate effectiveness of the proposed method.

关键词： mobile robot trajectory planning nonlinear dynamic optimal control

H. ZHANG, S. F. WANG, C. H. AN, J. WANG, Q. XU

《机械工程前沿（英文）》
2017年
第12卷
第2期
页码 193-202
*doi:*
*10.1007/s11465-017-0448-8*

摘要：

Large-aperture potassium dihydrogen phosphate (KDP) crystals are widely used in the laser path of inertial confinement fusion (ICF) systems. The most common method of manufacturing half-meter KDP crystals is ultra-precision fly cutting. When processing KDP crystals by ultra-precision fly cutting, the dynamic characteristics of the fly cutting machine and fluctuations in the fly cutting environment are translated into surface errors at different spatial frequency bands. These machining errors should be suppressed effectively to guarantee that KDP crystals meet the full-band machining accuracy specified in the evaluation index. In this study, the anisotropic machinability of KDP crystals and the causes of typical surface errors in ultra-precision fly cutting of the material are investigated. The structures of the fly cutting machine and existing processing parameters are optimized to improve the machined surface quality. The findings are theoretically and practically important in the development of high-energy laser systems in China.

关键词： ultra-precision fly cutting large-aperture KDP crystals spatial frequency processing error

线性离散时间系统H∞控制的极小极大Q-学习设计 Research Articles

李新兴1,奚乐乐2,3,查文中1,彭志红2

《信息与电子工程前沿（英文）》
2022年
第23卷
第3期
页码 438-451
*doi:*
*10.1631/FITEE.2000446*

摘要：
H∞控制是一种消除系统扰动的有效方式，但是由于需要求解非线性哈密顿—雅克比—伊萨克斯方程，H∞控制器往往很难得到，即便对于线性系统。本文考虑了线性离散时间系统的H∞控制器设计问题。将提出的极小极大Q-学习算法用于受负载扰动的电力系统H∞负载频率控制器设计，仿真结果表明，最终得到的H∞负载频率控制器具有良好抗干扰性能。

具有执行器饱和的分段仿射系统基于事件的H∞控制 Research Articles

蒋永豪,吴炜,楼旭阳,江正仙,崔宝同

《信息与电子工程前沿（英文）》
2021年
第22卷
第5期
页码 615-766
*doi:*
*10.1631/FITEE.1900601*

摘要：
该条件不仅能保证闭环系统在一定H∞性能指标下的稳定性，还能减少信号传输数量。最后，利用仿真实例验证该方法的有效性。

BHATESHVAR,H. D. MATHUR,H. SIGUERDIDJANE

《能源前沿（英文）》
2015年
第9卷
第1期
页码 7-21
*doi:*
*10.1007/s11708-014-0338-2*

摘要：
Among the available options for renewable energy integration in existing power system, wind power is being considered as one of the suited options for future electrical power generation. The major constraint of wind power generating system (WPGS) is that it does not provide inertial support because of power electronic converters between the grid and the WPGS to facilitate frequency stabilization. The proposed control strategy suggests a substantial contribution to system inertia in terms of short-term active power support in a two area restructured power system. The control scheme uses fuzzy logic based design and takes frequency deviation as input to provide quick active power support, which balances the drop in frequency and tie-line power during transient conditions. This paper presents a comprehensive study of the wind power impact with increasing wind power penetration on frequency stabilization in restructured power system scenario. Variation of load conditions are also analyzed in simulation studies for the same power system model with the proposed control scheme. Simulation results advocates the justification of control scheme over other schemes.

关键词： two area power system automatic generation control wind power generating system (WPGS) deregulated environment fuzzy logic controller (FLC)

reference tracking control design for a class of nonlinear systems with time-varying delays

Mei-qin LIU,Hai-yang CHEN,Sen-lin ZHANG

《信息与电子工程前沿（英文）》
2015年
第16卷
第9期
页码 759-768
*doi:*
*10.1631/FITEE.1500053*

摘要：
This paper investigates the trajectory tracking control for a class of nonlinear systems with timevarying delays by virtue of Lyapunov-Krasovskii stability theory and the linear matrix inequality (LMI) technique. A unified model consisting of a linear delayed dynamic system and a bounded static nonlinear operator is introduced, which covers most of the nonlinear systems with bounded nonlinear terms, such as the one-link robotic manipulator, chaotic systems, complex networks, the continuous stirred tank reactor (CSTR), and the standard genetic regulatory network (SGRN). First, the definition of the tracking control is given. Second, the performance analysis of the closed-loop system including this unified model, reference model, and state feedback controller is presented. Then criteria on the tracking controller design are derived in terms of LMIs such that the output of the closed-loop system tracks the given reference signal in the sense. The reference model adopted here is modified to be more flexible. A scaling factor is introduced to deal with the disturbance such that the control precision is improved. Finally, a CSTR system is provided to demonstrate the effectiveness of the established control laws.

关键词： H∞ reference tracking Nonlinear system State feedback control Time-varying delays Unified model

A pre-compensation method of the systematic contouring error for repetitive command paths

H. CHEN,Y. P. CHEN

《机械工程前沿（英文）》
2015年
第10卷
第4期
页码 367-372
*doi:*
*10.1007/s11465-015-0367-5*

摘要：

For a repetitive command path, pre-compensating the contouring error by modifying the command path is practical. To obtain the pre-compensation value with better accuracy, this paper proposes the use of a back propagation neural network to extract the function of systematic contouring errors. Furthermore, by using the extracted function, the contouring error can be easily pre-compensated. The experiment results verify that the proposed compensation method can effectively reduce contouring errors.

关键词： contouring error pre-compensation motion control system back propagation (BP) neural network

Yongli WANG, Shuyuan MA, Xiaodong Lü, Chuang XIE

《化学科学与工程前沿（英文）》
2012年
第6卷
第4期
页码 423-431
*doi:*
*10.1007/s11705-012-1211-7*

摘要：
5-(Difluoromethoxy)-2-mercapto-1 -benzimidazole (DMB) was precipitated by adding acetic acid to the DMB sodium salt solution. The spherical agglomeration of DMB during the reactive crystallization in a batch crystallizer was monitored by real-time Particle Video Microscope (PVM). We found that the low feeding rate of acetic acid, high crystallization temperature, low agitation rate or adding seed crystal can facilitate the formation of spherical agglomerates. By using a simple model, the mean crystal agglomerate size of DMB thus predicted is generally in agreement with the experimental data. In addition, the crystallization process of DMB was optimized by a new control strategy of supersaturation to avoid disadvantages brought by agglomeration.

关键词：
5-(difluoromethoxy)-2-mercapto-1

Jiao HU,Xiufan LIU

《农业科学与工程前沿（英文）》
2016年
第3卷
第1期
页码 11-24
*doi:*
*10.15302/J-FASE-2016092*

摘要：
The H9N2 and H5N1 avian influenza viruses (AIVs) have been circulating in poultry in China and become endemic since 1998 and 2004, respectively. Currently, they are prevalent in poultry throughout China. This endemicity makes them actively involved in the emergence of the novel lineages of other subtypes of influenza viruses, such as the well-known viruses of the highly pathogenic avian influenza (HPAI) H5N2 and the 2013 novel H7N7, H7N9 and H10N8 subtypes, thereby threatening both the poultry industry and public health. Here, we will review briefly the prevalence and evolution, pathogenicity, transmission, and disease control of these two subtypes and also discuss the possibility of emergence of potentially virulent and highly transmissible AIVs to humans.

关键词： avian influenza virus H9N2 H5N1 novel viruses public health

Development progress of China’s 600 km/h high-speed magnetic levitation train

《工程管理前沿（英文）》
2022年
第9卷
第3期
页码 509-515
*doi:*
*10.1007/s42524-022-0199-z*

摘要：
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关键词： 600 km/h high-speed magnetic levitation train development history technological innovation

Probes and nano-delivery systems targeting NAD(P)H:quinone oxidoreductase 1: a mini-review

《化学科学与工程前沿（英文）》
2023年
第17卷
第2期
页码 123-138
*doi:*
*10.1007/s11705-022-2194-7*

摘要：
The two-electron cytoplasmic reductase NAD(P)H:quinone oxidoreductase 1 is expressed in many tissues. NAD(P)H:quinone oxidoreductase 1 is well-known for being highly expressed in most cancers. Therefore, it could be a target for cancer therapy. Because it is a quinone reductase, many bioimaging probes based on quinone structures target NAD(P)H:quinone oxidoreductase 1 to diagnose tumours. Its expression is higher in tumours than in normal tissues, and using target drugs such as *β*-lapachone to reduce side effects in normal tissues can help. However, the physicochemical properties of *β*-lapachone limit its application. The problem can be solved by using nanosystems to deliver *β*-lapachone. This mini-review summarizes quinone-based fluorescent, near-infrared and two-photon fluorescent probes, as well as nanosystems for delivering the NAD(P)H:quinone oxidoreductase 1-activating drug *β*-lapachone. This review provides valuable information for the future development of probes and nano-delivery systems that target NAD(P)H:quinone oxidoreductase 1.

关键词： NAD(P)H:quinone oxidoreductase 1 cancer therapy target probe nanosystem

growth of a-few-layered MoS on CdS nanorod for high efficient photocatalytic H production

《能源前沿（英文）》
2021年
第15卷
第3期
页码 752-759
*doi:*
*10.1007/s11708-021-0779-3*

摘要：
An ultrathin MoS_{2} was grown on CdS nanorod by a solid state method using sulfur powder as sulfur source for photocatalytic H_{2} production. The characterization result reveals that the ultrathin MoS_{2} nanosheets loaded on CdS has a good contact state. The photoelectrochemical result shows that MoS_{2} not only are beneficial for charge separation, but also works as active sites, thus enhancing photocatalytic activity. Compared with pure CdS, the photocatalytic activity of MoS_{2} loaded CdS was significantly improved. The hydrogen evolution rate on *m*(MoS_{2}): *m*(CdS) = 1: 50 (*m* is mass) reaches 542 μmol/h, which is 6 times of that on pure CdS (92 μmol/h). This work provides a new design for photocatalysts with high photocatalytic activities and provides a deeper understanding of the effect of MoS_{2} on enhancing photocatalytic activity.

关键词：
photocatalytic H_{2} production
CdS
MoS_{2} cocatalyst
charge separation

标题 作者 时间 类型 操作

H_{∞} control in the frequency domain for a semi-active floor isolation system

Yundong SHI, Tracy C BECKER, Masahiro KURATA, Masayoshi NAKASHIMA

期刊论文

Trajectory planning of mobile robots using indirect solution of optimal control method in generalized

NAZEMIZADEH, H. N. RAHIMI, K. AMINI KHOIY

期刊论文

Full-band error control and crack-free surface fabrication techniques for ultra-precision fly cutting

H. ZHANG, S. F. WANG, C. H. AN, J. WANG, Q. XU

期刊论文

Impact of wind power generating system integration on frequency stabilization in multi-area power system with fuzzy logic controller in deregulated environment

BHATESHVAR,H. D. MATHUR,H. SIGUERDIDJANE

期刊论文

reference tracking control design for a class of nonlinear systems with time-varying delays

Mei-qin LIU,Hai-yang CHEN,Sen-lin ZHANG

期刊论文

A pre-compensation method of the systematic contouring error for repetitive command paths

H. CHEN,Y. P. CHEN

期刊论文

Control of the agglomeration of crystals in the reactive crystallization of 5-(difluoromethoxy)-2-mercapto

Yongli WANG, Shuyuan MA, Xiaodong Lü, Chuang XIE

期刊论文

Endemicity of H9N2 and H5N1 avian influenza viruses in poultry in China poses a serious threat to poultry

Jiao HU,Xiufan LIU

期刊论文