基于COSMOSMotion的水稻插秧机分插机构运动分析

建立了水稻插秧机分插机构秧针运动的数学模型,用SolidWorks对机构进行三维造型和装配,用与SolidWorks无缝集成的COSMOSMotion三维动力学仿真软件对分插机构进行运动仿真模拟,得到运动速度图及加速度图。从而使机构运动分析直观化、可视化,为选择合理的分插机构的结构参数、提高插秧性能提供依据。     

用于机载火控性能测试的六自由度运动模拟器参数设计

文章从机载火控模拟测试的需求出发，根据相关的技术指标要求，对六自由度运动模拟器进行了详细的动力学分析和运动学分析，给出了运动模拟器的结构参数和液压参数的设计过程，并对六自由度的运动精度进行了简要的分析。     

高速机构梁类弹性构件声辐射分析与计算

以四连杆机构的弹性连杆为研究对象，采用运动弹性动力学分析，求取振体表面法向速度；对其运动过程中的声辐射功率及结构模态声辐射效率进行了预测，为梁类高速运动弹性构件的声辐射控制提供了理论依据。     

一种机构运动可靠性的研究方法

利用机械系统动力学分析软件—ADAMS作为机构运动可靠性分析平台，进行机构的变参数设计，从而建立机构运动可靠性的仿真模型进行仿真分析，并应用蒙特卡洛法进行计算，在整个求解过程中，不需根据机构运动建立、求解复杂的解析数学方程，是机构运动可靠性分析计算的一种行之有效的方法。以曲柄滑块机构为例，研究考虑几何尺寸误差和运动副间隙误差对机构运动可靠性的综合影响。与传统方法相比较，使用该方法所得结果更加精确，而且适用于复杂机构，便于工程实际应用。     

典型机构运动可靠性的仿真研究

机构的运动可靠性理论分析是一个非常复杂的过程，目前均以简化的计算方法进行计算，这势必会给计算结果带来无法预计的误差。为避免这种误差的出现，应用机械系统动力学分析软件——ADAMS作为机构运动可靠性分析的平台并进行二次开发，最终形成常用机构运动可靠性的仿真分析模块。以曲柄滑块机构为例，使用CAD软件建模之后导入ADAMS，再利用ADAMS进行机构的变参数设计，从而建立机构的仿真模型，使用此分析模块进行仿真分析，并应用蒙特卡洛法进行计算。通过与传统方法相比较，此仿真研究方法是可行的。     

基于机构运动平稳的可靠性研究与结构优化设计

在产品设计中,往复机构的运动平稳性和可靠性直接影响机构的运动、动力性能和产品质量。文中从动力学和运动学的角度,对应用广泛的曲柄滑块机构开展基于运动平稳性的可靠性研究。通过建立曲柄滑块机构的等效力学模型,采用调整质心平衡法来减小振源,并利用MATLAB软件编程计算和仿真,以获取执行机构运动平稳规律;然后再综合考虑机构的尺寸误差和运动副间隙误差对机构运动可靠性的影响,并由此根据机械产品的实际情况确定并优化相关的运动参数,从而得到该机构最佳的运动平稳的可靠性结构。     

码垛小车机械系统动态特性的建模分析

建立了码垛升降小车机械系统的动力学模型 ,并应用运动弹性动力学方法分析了系统的动态特性。根据由小车工作行程确定的相应调速曲线来计算小车的瞬时位移 ,从而对模型进行了精确求解 ,获得了垂直方向振动速度与加速度的动态响应 ,为码垛机械系统动态性能的优化设计提供了依据。此外 ,对修改结构参数以提高动态性能进行了初步探讨。     

基于动力学性能的粉柱成型高速凸轮运动规律设计

粉柱成型凸轮机构在高速运转时，会引起从动件较大的弹性变形，机构会出现严重振动，从动件输出端运动将偏离预期运动，产生无法忽视的动态误差。此时采用传统方法所设计的凸轮机构运动规律无法完全满足工作需求，为此本文提出一种基于动力学性能的高速凸轮运动规律设计方法。首先建立凸轮传动系统的动力学模型，对其进行动力学分析。然后根据所得凸轮系统动力学特性建立动力学性能评价指标，再将样条曲线作为过渡曲线，建立优化目标函数，并通过遗传算法实现目标函数的求解。在以动力学指标为主的同时，本文还综合考虑了其它运动学指标，保证了高速凸轮机构从动件输出端的运动和动力稳定性，为高速凸轮机构运动规律的设计提供了一个实用的基于动力学性能的设计方法。     

涡旋压缩机径向随变机构动力学模型研究

对十字滑环防自转机构和带有径向随变机构的涡旋压缩机结构进行了分析和研究，根据其运动特性．建立了偏心套径向随变机构运动简图和引入虚约束以改善受力和机器运转平稳性的偏心套径向随变机构运动简图。依据机构运动简图可进行机器动力学问题的研究分析。     

基于ADAMS的摇摆式输送机运动学与动力学分析

运用虚拟样机仿真分析软件ADAMS,建立了摇摆式输送机虚拟样机模型,对其进行了运动学和动力学动态仿真,在虚拟环境中较真实地模拟了系统的运动.对关键点进行运动学动力学分析,观察各部件的相互运动及产品主体的受力情况,为摇摆式输送机的改进设计和结构优化提供了理论依据.     

Magnetically suspended contact-free linear actuator for precision stage

With the development of precision manufacturing technologies, the importance of precision positioning devices is increasing. Conventional actuators, dual stage or mechanically contacting type, have limitation in coping with performance demands. As a possible solution, magnetic suspension technology was studied. Such a contact-free system has advantages in terms of high accuracy, low production cost and easy adaptability to high precision manufacturing processes. This paper deals with magnetically suspended multi-degrees of freedom actuator which can realize large linear motion. In this paper, the operating principle is explained with the magnetic force analysis, and the equations of motion are derived. Experimental results of the implemented system are also given.     

Development of compact high precision linear piezoelectric stepping positioner with nanometer accuracy and large travel range

Many application areas such as semiconductor manufacture, precision optics alignment, and microbiological cell manipulation require ultraprecision positioning systems with a high positioning resolution and large motion range. This article describes the development of a compact high precision linear piezoelectric stepping positioner for precision alignment of optical elements. The positioner is designed to have a compact and symmetric structure, high positioning resolution, large motion range, high force density, adequate dynamic range, and power-off hold. The positioner is fabricated according to these specifications and performance evaluation tests are carried out. A resolution of 10 nm, speed of 1 mms, push force of 25 N, and stiffness of 10.4 N/microm are attained while maintaining a compact size of 32x42x60 mm(3). The required power consumption is 52.33 W. The test results confirm that the developed positioner could be successfully applied to the precision alignment of optical elements.     

柔性机械臂结构-控制耦合特征的实验研究

利用柔性机械臂主动控制实验装置以及相应的动力学参数测试系统 ,采用光电编码器、加速度计和应变片分别检测柔性臂的大范围运动、末端振动及驱动力矩 ,对柔性机械臂结构 -控制耦合特性进行了研究。实验结果发现 :1)由于结构与控制系统的耦合 ,改变了柔性机械臂的第一阶振动频率 ;2 )在实现规定运动时 ,不同结构的柔性机械臂的驱动力矩形式明显不同 ;3)柔性机械臂的驱动力矩具有随伺服驱动系统工频的脉动现象。验证了柔性机械臂结构与控制系统之间存在相互作用 ;指出采取结构 -控制一体化设计方法是提高柔性机械臂性能的一个重要手段。     

High-precision magnetic levitation stage for photolithography

In this paper, we present a high-precision magnetic levitation (maglev) stage for photolithography in semiconductor manufacturing. This stage is the world’s first maglev stage that provides fine six-degree-of-freedom motion controls and realizes large (50 mm × 50 mm) planar motions with only a single magnetically levitated moving part. The key element of this stage is a linear motor capable of providing forces in both suspension and translation without contact. The advantage of such a stage is that the mechanical design is far simpler than competing conventional approaches and, thus, promises faster dynamic response and higher mechanical reliability. The stage operates with a positioning noise as low as 5 nm rms in x and y, and acceleration capabilities in excess of 1 g (10 m/s²). We demonstrate the utility of this stage for next-generation photolithography or in other high-precision motion control applications.     

Design and precision construction of novel magnetic-levitation-based multi-axis nanoscale positioning systems

This paper presents two novel six-axis magnetic-levitation (maglev) stages capable of nanoscale positioning. These stages have very simple and compact structures, which is advantageous to meet the demanding positioning requirements of next-generation nanomanipulation and nanomanufacturing. Six-axis motion generation is accomplished by the minimum number of actuators and sensors. The first-generation maglev stage, namely the Δ-stage, is capable of generating translation of 300 μm and demonstrates position resolution better than 2 nm root-mean-square (rms). The second-generation maglev stage, namely the Y-stage, is capable of positioning at a resolution better than 3 nm rms over a planar travel range of 5 mm × 5 mm. A novel actuation scheme was developed for the compact structure of this stage that enables six-axis force generation with just three permanent-magnet pieces. This paper focuses on the design and precision construction of the actuator units, the moving platens, and the stationary base plates. The performance of the two precision positioners is compared in terms of their positioning and load-carrying capabilities and ease of manufacture. Control system design for the two positioners is discussed and an experimental plant transfer function model is presented for the Y-stage. The superiority of the developed instruments is also demonstrated over other prevailing precision positioning systems in terms of the travel range, resolution, and dynamic range. The potential applications of the maglev positioners include semiconductor manufacturing, microfabrication and assembly, nanoscale profiling, and nanoindentation.     

Recursive newton-euler formulation for flexible dynamic manufacturing analysis of open-loop robotic systems

The main objective of this paper is to develop a recursive formulation for the flexible dynamic manufacturing analysis of open-loop robotic systems. The nonlinear generalized Newton-Euler equations are used for flexible bodies that undergo large translational and rotational displacements. These equations are formulated in terms of a set of time invariant scalars, vectors and matrices that depend on the spatial coordinates as well as the assumed displacement fields. These time invariant quantities represent the dynamic manufacturing couplings between the rigid body motion and elastic deformation. This formulation applies recursive procedures with the generalized Newton-Euler equations for flexible bodies to obtain a large, loosely coupled system equation describing motion in flexible manufacturing systems. The techniques used to solve the system equations can be implemented in any computer system. The algorithms presented in this investigation are illustrated using cylindrical joints for open-loop robotic systems, which can be easily extended to revolute, slider and rigid joints. The recursive Newton-Euler formulation developed in this paper is demonstrated with a robotic system using cylindrical mechanical joints.     

Recursive Newton–Euler formulation for flexible dynamic manufacturing analysis of open-loop robotic systems

The main objective of this paper is to develop a recursive formulation for the flexible dynamic manufacturing analysis of open-loop robotic systems. The nonlinear generalized Newton–Euler equations are used for flexible bodies that undergo large translational and rotational displacements. These equations are formulated in terms of a set of time invariant scalars, vectors and matrices that depend on the spatial coordinates as well as the assumed displacement fields. These time invariant quantities represent the dynamic manufacturing couplings between the rigid body motion and elastic deformation. This formulation applies recursive procedures with the generalized Newton–Euler equations for flexible bodies to obtain a large, loosely coupled system equation describing motion in flexible manufacturing systems. The techniques used to solve the system equations can be implemented in any computer system. The algorithms presented in this investigation are illustrated using cylindrical joints for open-loop robotic systems, which can be easily extended to revolute, slider and rigid joints. The recursive Newton–Euler formulation developed in this paper is demonstrated with a robotic system using cylindrical mechanical joints.     

Development and application prospects of piezoelectric precision driving technology

With the rapid development of science and technology, microelectronics manufacturing, photonics technology, space technology, ultra-precision machining, micro-robotics, biomedical engineering and other fields urgently need the support of modern precision driving theory and technology. Modern precision driving technology can be generally divided into two parts: electromagnetic and non-electromagnetic driving technology. Electromagnetic driving technology is based on traditional technology, has a low thrust-weight ratio, and needs deceleration devices with a cumbrous system or a complex structure. Moreover, it is difficult to improve positioning accuracy with this technology type. Thus, electromagnetic driving technology is still unable to meet the requirements for the above applications. Non-electromagnetic driving technology is a new choice. As a category of non-electromagnetic driving technology, piezoelectric driving technology becomes an important branch of modern precision driving technology. High holding torque and acute response make it suitable as an accurate positioning actuator. This paper presents the development of piezoelectric precision driving technology at home and abroad and gives an in-depth analysis. Future perspectives on the technology’s applications in the following fields are described: 1) integrated circuit manufacturing technology; 2) fiber optic component manufacturing technology; 3) micro parts manipulation and assembly technology; 4) biomedical engineering; 5) aerospace technology; and 6) ultra-precision processing technology.     

Development and application prospects of piezoelectric precision driving technology

With the rapid development of science and technology, microelectronics manufacturing, photonics technology, space technology, ultra-precision machining, micro-robotics, biomedical engineering and other fields urgently need the support of modern precision driving theory and technology. Modern precision driving technology can be generally divided into two parts: electromagnetic and non-electromagnetic driving technology. Electromagnetic driving technology is based on traditional technology, has a low thrust-weight ratio, and needs deceleration devices with a cumbrous system or a complex structure. Moreover, it is difficult to improve positioning accuracy with this technology type. Thus, electromagnetic driving technology is still unable to meet the requirements for the above applications. Non-electromagnetic driving technology is a new choice. As a category of non-electromagnetic driving technology, piezoelectric driving technology becomes an important branch of modern precision driving technology. High holding torque and acute response make it suitable as an accurate positioning actuator. This paper presents the development of piezoelectric precision driving technology at home and abroad and gives an in-depth analysis. Future perspectives on the technology’s applications in the following fields are described: 1) integrated circuit manufacturing technology; 2) fiber optic component manufacturing technology; 3) micro parts manipulation and assembly technology; 4) biomedical engineering; 5) aerospace technology; and 6) ultra-precision processing technology.     

显微精密成像与微型机械尺寸检测技术

讨论了利用半导体或纳米制备技术和手段提供的物理空间晶格作为显微成像基准,对显微视觉成像系统的四维空间畸变进行提取、修正和实时标定,以实现视觉检测系统的精密数字成像,为微机械量、微几何量提供检测、评价和计量手段.对若干问题进行了详细的讨论,显微视觉检测是微机械量微几何量计量中最有效的方法之一,而精密数字成像是必须解决的问题之一.研究精密数字成像是视觉检测技术向微观检测领域发展所必须解决的科研课题.对微机械量和微几何量计量有重要意义