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半主动隔振；双级驱动；动态吸振；可调反共振频率控制器 1

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Optimal design of a linkage–cam mechanism-based redundantly actuated parallel manipulator

《机械工程前沿（英文）》 2021年 第16卷 第3期   页码 451-467 doi: 10.1007/s11465-021-0634-6

摘要： A redundantly actuated parallel manipulator (RAPM) with mixed translational and rotational degrees of freedom (DOFs) is challenged for its dimensionally homogeneous Jacobian modeling and optimal design of architecture. In this paper, a means to achieve redundant actuation by adding kinematic constraints is introduced, which reduces the DOFs of the end-effector (EE). A generic dimensionally homogeneous Jacobian is developed for this type of RAPMs, which maps the generalized velocities of three points on the EE to the joint velocities. A new optimization algorithm derived from this dimensionally homogeneous Jacobian is proposed for the optimal design of this type of RAPMs. As an example, this paper presents a spatial RAPM involving linkages and cam mechanisms. This RAPM has 4 DOFs and 6 translational actuations. The linkage lengths and the position of the universal joints of the RAPM are optimized based on the dimensionally homogeneous Jacobian.

关键词： redundant actuation     parallel manipulator     linkage–cam mechanism     Jacobian     optimal design    

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A redundantly actuated PRPRP radial mechanism in the segment erector of a shield machine for synchronization control

Wanghui BU, Zhenyu LIU, Jianrong TAN, Jin CHENG

《机械工程前沿（英文）》 2011年 第6卷 第4期   页码 463-467 doi: 10.1007/s11465-011-0225-z

摘要：

The shield machine is a heavy construction machine for tunnel excavation, and the segment erector is an important subsystem of the shield machine. It is difficult to achieve precise control in the 6-DOF (degree of freedom) erector in the 2-DOF 5-bar radial mechanism. Hence, this paper proposes a redundantly actuated PRPRP radial mechanism for the segment erector. When the redundant actuator is unlocked, the radial mechanism is able to adjust its posture, which has two degrees of freedom. On the other hand, when the redundant actuator is locked or produces enough pre-tightening tensile force, the PRPRP mechanism can ensure the synchronization of the two driving hydraulic cylinders along the radial direction based on the mechanical structure, which has one degree of freedom. The redundant actuator also facilitates the equal application of two flexural torques at the hydraulic cylinders; thus, preventing the overload of a single cylinder.

关键词： redundant actuation     parallel mechanisms     five-bar mechanisms     segment erectors     shield machines    

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Development of a redundant anthropomorphic hydraulically actuated manipulator with a roll–pitch–yaw spherical

《机械工程前沿（英文）》 2021年 第16卷 第4期   页码 698-710 doi: 10.1007/s11465-021-0646-2

摘要： The demand for redundant hydraulic manipulators that can implement complex heavy-duty tasks in unstructured areas is increasing; however, current manipulator layouts that remarkably differ from human arms make intuitive kinematic operation challenging to achieve. This study proposes a seven-degree-of-freedom (7-DOF) redundant anthropomorphic hydraulically actuated manipulator with a novel roll–pitch–yaw spherical wrist. A hybrid series–parallel mechanism is presented to achieve the spherical wrist design, which consists of two parallel linear hydraulic cylinders to drive the yaw/pitch 2-DOF wrist plate connected serially to the roll structure. Designed as a 1R PRRR-1S PU mechanism (“R”, “P”, “S”, and “U” denote revolute, prismatic, spherical, and universal joints, respectively; the underlined letter indicates the active joint), the 2-DOF parallel structure is partially decoupled to obtain simple forward/inverse kinematic solutions in which a closed-loop subchain “R PRR” is included. The 7-DOF manipulator is then designed, and its third joint axis goes through the spherical center to obtain closed-form inverse kinematic computation. The analytical inverse kinematic solution is drawn by constructing self-motion manifolds. Finally, a physical prototype is developed, and the kinematic analysis is validated via numerical simulation and test results.

关键词： hydraulic manipulator     inverse kinematic     redundant design     spherical wrist    

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Design and analysis of a class of redundant collaborative manipulators with 2-dimension large rotational

Xiaodong JIN, Yuefa FANG, Dan ZHANG, Xueling LUO

《机械工程前沿（英文）》 2020年 第15卷 第1期   页码 66-80 doi: 10.1007/s11465-019-0570-x

摘要： The parallel spindle heads with high rotational capability are demanded in the area of multi-axis machine tools and 3D printers. This paper focuses on designing a class of 2R1T (R: Rotation; T: Translation) parallel spindle heads and the corresponding collaborative 5-axis manipulators with 2-dimension (2D) large rotational angles. In order to construct 2D rotational degrees of freedom (DOF), a platform with 2-dimension revolute joints is proposed first. Based on the constraint screw theory, the feasible limbs that can be connected in the platform are synthesized. In order to provide constant rotational axis for the platform, a class of redundant limbs are designed. A class of redundant 2R1T parallel spindle heads is obtained by connecting the redundant limbs with the platform and the redundant characteristics are verified by the modified Grübler-Kutzbach criterion. The corresponding 5-axis collaborative manipulators are presented by constructing a 2-DOF series translational bottom moving platform. The inverse kinematics and the orientation workspace as well as the decoupling characteristics of this type of 2R1T parallel spindle heads are analyzed. The results show that these manipulators have large 2D rotational angles than the traditional A3/Z3 heads and can be potentially used in the application of multi-axis machine tools and the 3D printers.

关键词： parallel mechanism     redundant mechanism     large rotational angles     machine tools     2R1T spindle head     collaborative manipulator    

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A new method for boring of non-circular holes

ZHANG Kai, HU De-jin

《机械工程前沿（英文）》 2006年 第1卷 第4期   页码 456-460 doi: 10.1007/s11465-006-0058-3

摘要： A revolving electromagnetic actuation mechanism composed of an electromagnetic stator and an electromagnetic rotor has been developed for boring non-circular holes. The main component of the rotor is a flexure-hinged based flexible body. There are four pole-pair coils in the stator supplying actuation currents. The micro-displacement between the stator and rotor can be controlled by changing the currents applied in the pole-pair coils. Through linearization of the actuation force near the static action point, a linear relationship between the control current and the actuation force was established, and the synchronizing control method of the electromagnetic actuation mechanism is presented here. With two-factor analysis of the linearization error of the actuation force, the influences of control current and micro-displacement to the linearization error of the actuation force were studied. Then, the principle for designing the basic parameters of the magnetic actuation mechanism is put forward. The calibration of the mechanism indicates that the relationship between the micro-displacement of the rotor and the control current has linear characteristics in the required micro-displacement range. Simulation tests show that the turning radius of the rotor changes with the control current. The proposed mechanism can feasibly supply a controllable micro displacement to the boring bar.

关键词： electromagnetic actuation     control method     displacement     flexible body     revolving electromagnetic    

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Surface tension of liquid metal: role, mechanism and application

Xi ZHAO, Shuo XU, Jing LIU

《能源前沿（英文）》 2017年 第11卷 第4期   页码 535-567 doi: 10.1007/s11708-017-0463-9

摘要： Surface tension plays a core role in dominating various surface and interface phenomena. For liquid metals with high melting temperature, a profound understanding of the behaviors of surface tension is crucial in industrial processes such as casting, welding, and solidification, etc. Recently, the room temperature liquid metal (RTLM) mainly composed of gallium-based alloys has caused widespread concerns due to its increasingly realized unique virtues. The surface properties of such materials are rather vital in nearly all applications involved from chip cooling, thermal energy harvesting, hydrogen generation, shape changeable soft machines, printed electronics to 3D fabrication, etc. owing to its pretty large surface tension of approximately 700 mN/m. In order to promote the research of surface tension of RTLM, this paper is dedicated to present an overview on the roles and mechanisms of surface tension of liquid metal and summarize the latest progresses on the understanding of the basic knowledge, theories, influencing factors and experimental measurement methods clarified so far. As a practical technique to regulate the surface tension of RTLM, the fundamental principles and applications of electrowetting are also interpreted. Moreover, the unique phenomena of RTLM surface tension issues such as surface tension driven self-actuation, modified wettability on various substrates and the functions of oxides are discussed to give an insight into the acting mechanism of surface tension. Furthermore, future directions worthy of pursuing are pointed out.

关键词： surface tension     liquid metal     soft machine     printed electronics     electrowetting     self-actuation    

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Ahybrid biogeography-based optimization method for the inverse kinematics problem of an 8-DOF redundant

Zi-wu REN,Zhen-hua WANG,Li-ning SUN

《信息与电子工程前沿（英文）》 2015年 第16卷 第7期   页码 607-616 doi: 10.1631/FITEE.14a0335

摘要： The redundant humanoid manipulator has characteristics of multiple degrees of freedom and complex joint structure, and it is not easy to obtain its inverse kinematics solution. The inverse kinematics problem of a humanoid manipulator can be formulated as an equivalent minimization problem, and thus it can be solved using some numerical optimization methods. Biogeography-based optimization (BBO) is a new biogeography inspired optimization algorithm, and it can be adopted to solve the inverse kinematics problem of a humanoid manipulator. The standard BBO algorithm that uses traditional migration and mutation operators suffers from slow convergence and prematurity. A hybrid biogeography-based optimization (HBBO) algorithm, which is based on BBO and differential evolution (DE), is presented. In this hybrid algorithm, new habitats in the ecosystem are produced through a hybrid migration operator, that is, the BBO migration strategy and DE/best/1/bin differential strategy, to alleviate slow convergence at the later evolution stage of the algorithm. In addition, a Gaussian mutation operator is adopted to enhance the exploration ability and improve the diversity of the population. Based on these, an 8-DOF (degree of freedom) redundant humanoid manipulator is employed as an example. The end-effector error (position and orientation) and the ‘away limitation level’ value of the 8-DOF humanoid manipulator constitute the fitness function of HBBO. The proposed HBBO algorithm has been used to solve the inverse kinematics problem of the 8-DOF redundant humanoid manipulator. Numerical simulation results demonstrate the effectiveness of this method.

关键词： Inverse kinematics problem     8-DOF humanoid manipulator     Biogeography-based optimization (BBO)     Differential evolution (DE)    

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一种用于文本分类的去冗余特征选择新方法 None

You-wei WANG, Li-zhou FENG

《信息与电子工程前沿（英文）》 2018年 第19卷 第2期   页码 221-234 doi: 10.1631/FITEE.1601761

摘要： 特征选择是文本分类领域一种重要降维方法。针对传统特征选择方法所选特征集常包含冗余信息的问题，提出一种能够有效去除冗余信息的特征选择新方法。首先，为衡量两个词之间的关系，引入基于词频的相关性和相对冗余词集的概念；接着，选择一种最优特征选择方法并用其获得一个临时特征子集；最后，为提高算法执行效率，结合预设阈值去除临时特征子集中的冗余特征，并将结果存储在链表结构中。实验以支持向量机和朴素贝叶斯作为分类器，并以WebKB、20-Newsgroups和Reuters-21578作为测试数据集。实验结果表明，该方法分类精度高于传统特征选择方法；相对于基于互信息的方法而言，该方法能够在保证分类精度的同时，有效提高运行效率。

关键词： 特征选择；降维；文本分类；冗余特征；支持向量机；朴素贝叶斯；互信息    

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Optimal redundant placement of PMUs in Indian power grid — northern, eastern and north-eastern regions

Pathirikkat GOPAKUMAR, G. Surya CHANDRA, M. Jaya Bharata REDDY, Dusmata Kumar MOHANTA

《能源前沿（英文）》 2013年 第7卷 第4期   页码 413-428 doi: 10.1007/s11708-013-0274-6

摘要： Effective utilization of renewable energy sources and efficient management of electric energy are essential for any developing countries like India. This can be envisioned through the implementation of concepts of smart grid (SG). One of the key requisites for SG implementation is that the grid should be completely observable. Renovation of conventional Indian power grid to a SG necessitates incorporation of the phasor measurement units (PMUs) in the present power grid measurement and monitoring system. Since the cost of PMU is high and any bus containing a PMU makes the neighboring connected buses observable, optimal placement of PMUs is very important for complete observability of the grid. This paper proposes optimal redundant geographical locations in the northern, eastern and north-eastern regions of Indian power grid for PMU placement. The PMUs installed in these geographical locations will make the grid completely observable and maintain the observability under the conditions of failure of some PMUs or branch outages. Integer linear programming has been used for finding the optimal PMU locations. The results proposed in this paper can be a stepping stone for revamping the Indian power grid to a SG ensuring complete observability during different contingency conditions.

关键词： phasor measurement unit (PMU)     smart grid (SG)     Indian power grid     northern region Indian power grid (NRIPG)     eastern region Indian power grid (ERIPG)     north-eastern region Indian power grid (NERIPG)     redundancy     integer linear programing (ILP)    

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Precise semi-analytical inverse kinematic solution for 7-DOF offset manipulator with arm angle optimization

《机械工程前沿（英文）》 2021年 第16卷 第3期   页码 435-450 doi: 10.1007/s11465-021-0630-x

摘要： Seven-degree-of-freedom redundant manipulators with link offset have many advantages, including obvious geometric significance and suitability for configu-ration control. Their configuration is similar to that of the experimental module manipulator (EMM) in the Chinese Space Station Remote Manipulator System. However, finding the analytical solution of an EMM on the basis of arm angle parameterization is difficult. This study proposes a high-precision, semi-analytical inverse method for EMMs. Firstly, the analytical inverse kinematic solution is established based on joint angle parameterization. Secondly, the analytical inverse kinematic solution for a non-offset spherical–roll–spherical (SRS) redundant manipulator is derived based on arm angle parameterization. The approximate solution of the EMM is calculated in accordance with the relationship between the joint angles of the EMM and the SRS manipulator. Thirdly, the error is corrected using a numerical method through the analytical inverse solution based on joint angle parameterization. After selecting the stride and termination condition, the precise inverse solution is computed for the EMM based on arm angle parameterization. Lastly, case solutions confirm that this method has high precision, and the arm angle parameterization method is superior to the joint angle parameterization method in terms of parameter selection.

关键词： 7-DOF redundant manipulator     inverse kinematics     semi-analytical     arm angle     link offset    

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振动驱动的微型机器人非完整约束补偿的定位方法 Article

Kostas Vlachos, Dimitris Papadimitriou, Evangelos Papadopoulos

《工程（英文）》 2015年 第1卷 第1期   页码 66-72 doi: 10.15302/J-ENG-2015016

摘要：

本文提出了一种微型移动机器人非完整约束补偿的定位方法，推导了相关公式并进行了实际操作。该移动机器人由两台振动型直流微型电机驱动。本文所描述的开环法和闭环法增加了微型机器人平台侧向净位移的能力，这是通过执行若干重复步骤来实现的，这些步骤与期望位置、速度和时间相关。仿真和试验结果验证了所述方法的有效性。

关键词： 微型机器人     振动微电机     非完整驱动规划     非完整约束补偿    

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A modular design kit for task-adaptable low-cost robots based on BaPaMan design

G. BORCHERT, C. L?CHTE, G. CARBONE, A. RAATZ

《机械工程前沿（英文）》 2013年 第8卷 第1期   页码 33-41 doi: 10.1007/s11465-013-0356-5

摘要：

This paper discusses the redesign of a binary parallel manipulator named BaPaMan (Binary Actuated Parallel Manipulator). The aim of this work is the improvement of the structures stiffness of BaPaMan. Additionally this paper shows the implementation of a construction kit which allows task-adaptation of low-cost robots based on the BaPaMan structure. BaPaMan is a three degree of freedom (DOF) spatial parallel robot which comprises flexure hinges and Shape Memory Alloy (SMA) actuators to achieve a low-cost design, well suited for easy operation applications. Measurements have shown that this comes at the cost of poor structural stiffness and end effector accuracy. To counter these issues BaPaMan2 and BaPaMan3 have been developed and are elaborated within this work. During the design phase, an empirical FEA is used to improve the flexure hinge performance, which analyses relations between several design parameters and the stiffness of the entire system. Finally, task-adaptation is achieved by using a design methodology and a parametric CAD model for BaPaMan. Besides the paper introduces first applications of the BaPaMan structure and shows future work.

关键词： binary actuation     flexure hinges     SMA actuators     low-cost     design kit     task-adaptation    

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Unconventional hydrodynamics of hybrid fluid made of liquid metals and aqueous solution under applied fields

Xu-Dong ZHANG, Yue SUN, Sen CHEN, Jing LIU

《能源前沿（英文）》 2018年 第12卷 第2期   页码 276-296 doi: 10.1007/s11708-018-0545-3

摘要： The hydrodynamic characteristics of hybrid fluid made of liquid metal/aqueous solution are elementary in the design and operation of conductive flow in a variety of newly emerging areas such as chip cooling, soft robot, and biomedical practices. In terms of physical and chemical properties, such as density, thermal conductivity and electrical conductivity, their huge differences between the two fluidic phases remain a big challenge for analyzing the hybrid flow behaviors. Besides, the liquid metal immersed in the solution can move and deform when administrated with non-contact electromagnetic force, or even induced by redox reaction, which is entirely different from the cases of conventional contact force. Owing to its remarkable capability in flow and deformation, liquid metal immersed in the solution is apt to deform on an extremely large scale, resulting in marked changes on its boundary and interface. However, the working mecha- nisms of the movement and deformation of liquid metal lack appropriate models to describe such scientific issues via a set of well-established unified equations. To promote investigations in this important area, the present paper is dedicated to summarizing this unconventional hydrodynamics from experiment, theory, and simulation. Typical experimental phenomena and basic working mechanisms are illustrated, followed by the movement and deformation theories to explain these phenomena. Several representative simulation methods are then proposed to tackle the governing functions of the electrohydrodynamics. Finally, prospects and challenges are raised, offering an insight into the new physics of the hybrid fluid under applied fields.

关键词： liquid metal     hybrid fluid     hydrodynamics     surface tension     applied fields     self-actuation    

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自恢复容错系统的建模与分析

郭成昊,刘凤玉

《中国工程科学》 2007年 第9卷 第10期   页码 75-79

摘要：

容错系统不仅会产生硬件故障，由于连续长时间的运行，系统的性能也会逐渐下降或失效，即老化现象。综合考虑容错系统中的硬件故障和老化现象，提出了将传统的冗余技术和软件抗衰技术相结合的策略，并给出了该系统的非马尔可夫随机Petri网模型，随之对基于该模型的系统进行了定量分析。

关键词： 容错系统     软件抗衰     软件老化     冗余策略     非马尔可夫随机Petri网    

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具有冗余结构的分布式数据库服务器及其负载平衡模型

田俊峰,刘玉玲,杜瑞忠

《中国工程科学》 2004年 第6卷 第6期   页码 35-42

摘要：

服务器冗余技术在解决传统分布式环境的可用性和性能瓶颈问题的同时给系统的管理带来了新的挑战。介绍了一种分布式数据库服务器的构成原理及工作模型，重点讨论了它的冗余关系、基于移动代理的负载平衡模型及其性能分析等。

关键词： 分布式数据库     冗余     负载平衡     移动代理     性能分析    

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标题 作者 时间 类型 操作

Optimal design of a linkage–cam mechanism-based redundantly actuated parallel manipulator

期刊论文

A redundantly actuated PRPRP radial mechanism in the segment erector of a shield machine for synchronization control

Wanghui BU, Zhenyu LIU, Jianrong TAN, Jin CHENG

期刊论文

Development of a redundant anthropomorphic hydraulically actuated manipulator with a roll–pitch–yaw spherical

期刊论文

Design and analysis of a class of redundant collaborative manipulators with 2-dimension large rotational

Xiaodong JIN, Yuefa FANG, Dan ZHANG, Xueling LUO

期刊论文

A new method for boring of non-circular holes

ZHANG Kai, HU De-jin

期刊论文

Surface tension of liquid metal: role, mechanism and application

Xi ZHAO, Shuo XU, Jing LIU

期刊论文

Ahybrid biogeography-based optimization method for the inverse kinematics problem of an 8-DOF redundant

Zi-wu REN,Zhen-hua WANG,Li-ning SUN

期刊论文

一种用于文本分类的去冗余特征选择新方法

You-wei WANG, Li-zhou FENG

期刊论文

Optimal redundant placement of PMUs in Indian power grid — northern, eastern and north-eastern regions

Pathirikkat GOPAKUMAR, G. Surya CHANDRA, M. Jaya Bharata REDDY, Dusmata Kumar MOHANTA

期刊论文

Precise semi-analytical inverse kinematic solution for 7-DOF offset manipulator with arm angle optimization

期刊论文

振动驱动的微型机器人非完整约束补偿的定位方法

Kostas Vlachos, Dimitris Papadimitriou, Evangelos Papadopoulos

期刊论文

A modular design kit for task-adaptable low-cost robots based on BaPaMan design

G. BORCHERT, C. L?CHTE, G. CARBONE, A. RAATZ

期刊论文

Unconventional hydrodynamics of hybrid fluid made of liquid metals and aqueous solution under applied fields

Xu-Dong ZHANG, Yue SUN, Sen CHEN, Jing LIU

期刊论文

自恢复容错系统的建模与分析

郭成昊,刘凤玉

期刊论文

具有冗余结构的分布式数据库服务器及其负载平衡模型

田俊峰,刘玉玲,杜瑞忠

期刊论文