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Comprehensive analysis of the influence of structural and dynamic parameters on the accuracy of nano-precisionpositioning stages

Chengyuan LIANG, Fang YUAN, Xuedong CHEN, Wei JIANG, Lizhan ZENG, Xin LUO

《机械工程前沿(英文)》 2019年 第14卷 第3期   页码 255-272 doi: 10.1007/s11465-019-0538-x

摘要: Nano-precision positioning stages are characterized by rigid-flexible coupling systems. The complex dynamic characteristics of mechanical structure of a stage, which are determined by structural and dynamic parameters, exert a serious influence on the accuracy of its motion and measurement. Systematic evaluation of such influence is essential for the design and improvement of stages. A systematic approach to modeling the dynamic accuracy of a nano-precision positioning stage is developed in this work by integrating a multi-rigid-body dynamic model of the mechanical system and measurement system models. The influence of structural and dynamic parameters, including aerostatic bearing configurations, motion plane errors, foundation vibrations, and positions of the acting points of driving forces, on dynamic accuracy is investigated by adopting the H-type configured stage as an example. The approach is programmed and integrated into a software framework that supports the dynamic design of nano-precision positioning stages. The software framework is then applied to the design of a nano-precision positioning stage used in a packaging lithography machine.

关键词: nano-precision positioning stage     analysis and design     structural and dynamic parameters     dynamic accuracy     systematic modeling    

Mechatronic design of a novel linear compliant positioning stage with large travel range and high out-of-plane

Hua LIU, Xin XIE, Ruoyu TAN, Lianchao ZHANG, Dapeng FAN

《机械工程前沿(英文)》 2017年 第12卷 第2期   页码 265-278 doi: 10.1007/s11465-017-0453-y

摘要:

Most of the XY positioning stages proposed in previous studies are mainly designed by considering only a single performance indicator of the stage. As a result, the other performance indicators are relatively weak. In this study, a 2-degree-of-freedom linear compliant positioning stage (LCPS) is developed by mechatronic design to balance the interacting performance indicators and realize the desired positioning stage. The key parameters and the coupling of the structure and actuators are completely considered in the design. The LCPS consists of four voice coil motors (VCMs), which are conformally designed for compactness, and six spatial leaf spring parallelograms. These parallelograms are serially connected for a large travel range and a high out-of-plane payload capacity. The mechatronic model is established by matrix structural analysis for structural modeling and by Kirchhoff’s law for the VCMs. The sensitivities of the key parameters are analyzed, and the design parameters are subsequently determined. The analytical model of the stage is confirmed by experiments. The stage has a travel range of 4.4 mm× 7.0 mm and a 0.16% area ratio of workspace to the outer dimension of the stage. The values of these performance indicators are greater than those of any existing stage reported in the literature. The closed-loop bandwidth is 9.5 Hz in both working directions. The stage can track a circular trajectory with a radius of 1.5 mm, with 40 mm error and a resolution of lower than 3 mm. The results of payload tests indicate that the stage has at least 20 kg out-of-plane payload capacity.

关键词: mechatronic design     linear compliant positioning stage     large travel range     high out-of-plane payload capacity     spatial parallelogram     voice coil motor     sensitivity analysis    

数控车床丝杠进给系统刚度对定位精度的影响

吴南星,胡如夫,孙庆鸿

《中国工程科学》 2004年 第6卷 第9期   页码 46-49

摘要:

数控车床丝杠进给系统刚度对系统的失动量和定位精度影响较大。基于进给系统质量和弹簧力学模型,给出了进给系统轴向刚度和扭转刚度对失动量的影响与定位误差的解析表达式,为进给系统结构设计、降低系统的失动量和提高系统的定位精度提供了理论依据;结合实例进行了应用分析计算,取得了明显效果。

关键词: 数控机床     刚度     失动量     定位精度    

Model reduction techniques for dynamics analysis of ultra-precision linear stage

Xuedong CHEN, Zhixin LI

《机械工程前沿(英文)》 2009年 第4卷 第1期   页码 64-70 doi: 10.1007/s11465-009-0009-x

摘要: Spring-damping elements are used to simplify the internal interaction in the proposed finite element (FE) model of an ultra-precision linear stage. The dynamics behavior is studied. The comparison between mode shapes from the eigenvalue analysis shows that the components, except the translator, can represent system dynamics characteristics. A reduction approach is used to simplify the system in a dynamic studied. There is little difference between the vibration mode and the response analysis. The experimental modal analysis proves the validity of the reduction approach, which can be generalized to the development and dynamics characteristic study of a complex system model to obviously save computational resource.

关键词: dynamics analysis     air-bearing     linear stage     reduction    

Precision control system of two-DOF stage with linear ultrasonic motor

ZHANG Hanlei, SHI Yunlai, ZHAO Chunsheng

《机械工程前沿(英文)》 2008年 第3卷 第4期   页码 421-425 doi: 10.1007/s11465-008-0063-9

摘要: Using an appropriate control method, linear ultrasonic motors can be used in applications requiring high position accuracy. In this paper, a closed loop PI control system is designed to achieve high position accuracy during the control of a two-DOF stage driven by linear ultrasonic motors. Two ultrasonic motors are mounted on the stage to generate motion in two orthogonal directions. The PI control algorithm is used to increase the stability and accuracy of position control. The -axis mover covers 30 mm forward and backward in less than 0.3 s settling time and the -axis mover in less than 0.4 s. Experimental results denote that the control strategy proposed in this paper appears to have high efficiency, quick response, and high accuracy.

关键词: settling     position accuracy     PI control     control algorithm     orthogonal    

基于惯性能时空最优分布的高加速轻载机构精密定位方法 Article

陈新,白有盾,杨志军,高健,陈贡发

《工程(英文)》 2015年 第1卷 第3期   页码 391-398 doi: 10.15302/J-ENG-2015063

摘要:

高速运动精密定位是微电子封装设备中高加速轻载执行机构的基本运动需求。本文推导了高加速机构瞬态非线性动力学响应方程,揭示了刚度、频率、阻尼 (与材料空间布局相关) 和驱动频率 (与运动规划相关) 是主要影响因素。据此,在满足高加速机构精密定位的条件下,笔者提出了一种基于最优非线性动力学响应的结构优化和速度规划新方法。在结构优化中,首先分析了目前流行的基于等效静态载荷的柔性多体动力学优化方法未充分考虑惯性载荷的不足,然后提出了基于等效模态的柔性多体动力学最优动态响应优化新方法;在速度规划上,针对传统的几何光滑方法不能反映系统动态特性的缺陷,提出了基于变边界条件非线性动力学响应优化的速度规划新方法。将所提方法应用到高速固晶焊头的优化设计中,通过结构优化,降低振幅超过20%,再经非对称变加速规划,缩短定位时间超过40%。本文提出的方法为微电子封装类装备等高加速轻载机构精密定位的实现提供了有效的理论支撑和解决途径。

关键词: 高加速轻载机构     精密定位     时空分布     惯性能     等效静态载荷方法     速度规划    

悬索桥钢索塔下塔柱大节段吊装施工技术

张平,肖文福,黄涛,蒋建,蔡伟

《中国工程科学》 2010年 第12卷 第4期   页码 58-62

摘要:

泰州大桥为国内首次主跨跨径超越千米的三塔两跨悬索桥,中塔首次采用纵向人字型、横向门字型钢结构塔。文章对钢塔下塔柱大节段安装、定位、调位及设备选型、精度控制等施工技术作简单的介绍。

关键词: 钢塔大节段     吊装     定位     调位     精度控制     定位系统    

三塔悬索桥中间塔施工关键技术

田唯,刘建波,游新鹏

《中国工程科学》 2012年 第14卷 第5期   页码 23-28

摘要:

泰州大桥中间塔采用深水沉井基础与纵向“人”字形钢塔相组合的结构形式,其施工极为复杂。该项目通过前期研究成果,在深水沉井基础施工过程中利用上下游锚墩定位技术,结合信息化实时监控系统,确保了沉井的准确定位和精确着床,同时采用终沉控制措施成功防止了沉井在终沉阶段的突沉、超沉现象。钢塔架设精度高,调整节段少,且在安装过程中结构存在多次体系转换,针对以上特点,采用几何控制的全过程控制理念,将节段制造误差、预拼装线性和架设误差进行统一分析,建立精度管理系统,最终钢塔的架设精度远远优于设计精度。泰州大桥中间塔施工取得了

关键词: 泰州大桥     锚墩定位     实时监控     终沉控制     全过程控制     架设精度    

Kinematic calibration of precise 6-DOF stewart platform-type positioning systems for radio telescope

Juan Carlos JáUREGUI, Eusebio E. HERNáNDEZ, Marco CECCARELLI, Carlos LóPEZ-CAJúN, Alejandro GARCíA

《机械工程前沿(英文)》 2013年 第8卷 第3期   页码 252-260 doi: 10.1007/s11465-013-0249-7

摘要:

The pose accuracy of a parallel robot is a function of the mobile platform posture. Thus, there is no a single value of the robot’s accuracy. In this paper, two novel methods for estimating the accuracy of parallel robots are presented. In the first method, the pose accuracy estimation is calculated by considering the propagation of each error, i.e., error variations are considered as a function of the actuator’s stroke. In the second method, it is considered that each actuator has a constant error at any stroke. Both methods can predict pose accuracy of precise robots at design stages, and/or can reduce calibration time of existing robots. An example of a six degree-of-freedom parallel manipulator is included to show the application of the proposed methods.

关键词: pose errors     error estimation     parallel robot     radio telescopes    

Water-dispersible nano-pollutions reshape microbial metabolism in type-specific manners: A metabolic

《环境科学与工程前沿(英文)》 2022年 第16卷 第9期 doi: 10.1007/s11783-022-1548-1

摘要:

• Water-dispersible nano-pollutions exhibit type-specific toxic effects on E. coli.

关键词: Nano-toxicity     Nano-plastics     Quantum dots     Microbial metabolite     Metabolic dysregulation    

Laboratory investigation of emulsified asphalt binder modified with wood-derived nano-cellulose and nano

Yunge WEI; Jiayu WANG; Ruoyu LI; Ling XU; Feipeng XIAO

《结构与土木工程前沿(英文)》 2022年 第16卷 第11期   页码 1474-1485 doi: 10.1007/s11709-022-0869-2

摘要: Emulsified asphalt is the primary material for preventive maintenance and cold-mix paving, but its low cohesive strength and poor mechanical properties limit its wide application, even with polymer modification. In this study, Styrene-Butadiene Rubber (SBR) emulsified asphalt was modified with nano-cellulose materials, namely nano paper-cellulose (NPC) and wood-derived nano-cellulose (WDC), to improve its properties. A novel preparation method of nano-cellulose solution was developed, including blending, ultrasonic stirring, and centrifugal treatment. Four types of nano-cellulose solution (0.5% NPC, 0.5%, 1.0%, and 1.5% WDC by weight of water) were selected. The microscopy analysis indicated that 0.5% WDC emulsion had a smaller particle size than 1.5% WDC emulsion. The rheology test indicated that WDC modified residue improved rutting resistance with the increased solution dosage due to the cross-linking effect, but its creep-and-recovery performance was worse than that of SBR emulsion residue. The NPC modified binder had a higher rutting factor than WDC modified binder at the same dosage after short-term aging. In addition, 1.0% WDC could be regarded as the optimal dosage in terms of fatigue and low-temperature performance. Furthermore, Fourier Transform Infrared Spectroscopy (FTIR) results showed that 0.5% NPC modified residue performed better in long-term aging resistance compared with 0.5%WDC modified asphalt.

关键词: nano-cellulose     emulsified asphalt binder     dispersion     rheological properties     Fourier transform infrared spectroscopy    

Do not let precision medicine be kidnapped

null

《医学前沿(英文)》 2015年 第9卷 第4期   页码 512-513 doi: 10.1007/s11684-015-0425-8

摘要:

Obama’s precision medicine initiative made the medical community boil over after the initiative’s release. Precision medicine has been advocated by the majority of scientists and doctors. However, some experts have questioned this concept. This article does not oppose precision medicine. However, the incentive of vigorously promoting precision medicine at present is a concern.

关键词: precision medicine     personalized medicine     genomics    

面向大幅面金属增材抛光的激光扫描振镜与伺服台协同控制系统 Article

崔梦嘉, 卢立斌, 张震, 管迎春

《工程(英文)》 2021年 第7卷 第12期   页码 1732-1740 doi: 10.1016/j.eng.2020.06.028

摘要:

为了满足高品质金属增材制造的迫切需求,本文创新地提出了一种以激光扫描振镜与精密伺服台协同控制为核心的大幅面激光精密抛光方法,以实现大幅面选区激光熔化(SLM)成形镍合金精密抛光。我们提出的协同控制系统主要包括主从式新型协同控制架构、运动矢量分解和误差合成等核心模块。研究实验结果表明,与传统步进-扫描方法相比,该协同控制系统实现了激光光斑连续运动,避免了拼接误差,加工效率提升了38.24%。由于激光扫描路径更流畅,相应能量分布更均匀,因此,大幅面抛光质量得到显著改善。本协同系统为大幅面、高精度、高效率的激光精密加工提供了重要途径,在航空航天、新能源、高端模具、医疗器械等精密制造领域具有广阔的应用前景。

关键词: 协同控制     激光制造     拼接误差     激光抛光     大幅面    

Review on the progress of ultra-precision machining technologies

Julong YUAN, Binghai LYU, Wei HANG, Qianfa DENG

《机械工程前沿(英文)》 2017年 第12卷 第2期   页码 158-180 doi: 10.1007/s11465-017-0455-9

摘要:

Ultra-precision machining technologies are the essential methods, to obtain the highest form accuracy and surface quality. As more research findings are published, such technologies now involve complicated systems engineering and been widely used in the production of components in various aerospace, national defense, optics, mechanics, electronics, and other high-tech applications. The conception, applications and history of ultra-precision machining are introduced in this article, and the developments of ultra-precision machining technologies, especially ultra-precision grinding, ultra-precision cutting and polishing are also reviewed. The current state and problems of this field in China are analyzed. Finally, the development trends of this field and the coping strategies employed in China to keep up with the trends are discussed.

关键词: ultra-precision grinding     ultra-precision cutting     ultra-precision polishing     research status in China     development tendency    

Self-generation of machining precision and its realization in lapping of super precision solid balls

ZHANG Bopeng

《机械工程前沿(英文)》 2008年 第3卷 第3期   页码 348-353 doi: 10.1007/s11465-008-0065-7

摘要: This paper presents the principle of self-generation of machining precision by explaining its basic concept and five necessary conditions for forming a system with self-organization capability. A self-generation system is a kind of system with self-organization capability. The self-generation of machining precision for solid balls with super precision is emphatically explained. From the viewpoint of self-organization, there are three types of systems including system 1 with the self-regulation capability, 2 with the self-determination capability of goals, and 3 with the self-organization capability. Although they are all closed loop control systems, they have different constructions and functions. Necessary conditions for achieving self-generation of machining precision are given. Establishment of the system for machining solid balls with super precision is discussed. Self-generation of machining precision for solid balls with super precision on the basis of the capability of self-removal of errors is presented. Self-generation includes the ability of self-removal of errors for solid balls, convergence of self-removal of errors, self-generation of precision, and self-generating system for the given.

关键词: self-generation     necessary     self-regulation capability     viewpoint     Necessary    

标题 作者 时间 类型 操作

Comprehensive analysis of the influence of structural and dynamic parameters on the accuracy of nano-precisionpositioning stages

Chengyuan LIANG, Fang YUAN, Xuedong CHEN, Wei JIANG, Lizhan ZENG, Xin LUO

期刊论文

Mechatronic design of a novel linear compliant positioning stage with large travel range and high out-of-plane

Hua LIU, Xin XIE, Ruoyu TAN, Lianchao ZHANG, Dapeng FAN

期刊论文

数控车床丝杠进给系统刚度对定位精度的影响

吴南星,胡如夫,孙庆鸿

期刊论文

Model reduction techniques for dynamics analysis of ultra-precision linear stage

Xuedong CHEN, Zhixin LI

期刊论文

Precision control system of two-DOF stage with linear ultrasonic motor

ZHANG Hanlei, SHI Yunlai, ZHAO Chunsheng

期刊论文

基于惯性能时空最优分布的高加速轻载机构精密定位方法

陈新,白有盾,杨志军,高健,陈贡发

期刊论文

悬索桥钢索塔下塔柱大节段吊装施工技术

张平,肖文福,黄涛,蒋建,蔡伟

期刊论文

三塔悬索桥中间塔施工关键技术

田唯,刘建波,游新鹏

期刊论文

Kinematic calibration of precise 6-DOF stewart platform-type positioning systems for radio telescope

Juan Carlos JáUREGUI, Eusebio E. HERNáNDEZ, Marco CECCARELLI, Carlos LóPEZ-CAJúN, Alejandro GARCíA

期刊论文

Water-dispersible nano-pollutions reshape microbial metabolism in type-specific manners: A metabolic

期刊论文

Laboratory investigation of emulsified asphalt binder modified with wood-derived nano-cellulose and nano

Yunge WEI; Jiayu WANG; Ruoyu LI; Ling XU; Feipeng XIAO

期刊论文

Do not let precision medicine be kidnapped

null

期刊论文

面向大幅面金属增材抛光的激光扫描振镜与伺服台协同控制系统

崔梦嘉, 卢立斌, 张震, 管迎春

期刊论文

Review on the progress of ultra-precision machining technologies

Julong YUAN, Binghai LYU, Wei HANG, Qianfa DENG

期刊论文

Self-generation of machining precision and its realization in lapping of super precision solid balls

ZHANG Bopeng

期刊论文