实现变超椭圆轨迹混合驱动凸轮连杆机构的研究

将混合驱动理论应用于凸轮连杆机构,介绍了混合驱动凸轮连杆机构的概念和意义.在对其进行了运动学分析的基础上,使用图解法推导出混合驱动凸轮连杆机构柔性空间边界条件.指出混合驱动凸轮连杆机构再现轨迹应满足柔性空间边界条件和运动学几何约束条件.设计了实现成组超椭圆轨迹的凸轮连杆机构实例.仿真实例结果表明,混合驱动凸轮连杆机构可以在比较规范的柔性空间内精确实现复杂的相同运动规律或不同运动规律的成组轨迹.     

平面连杆机构再现轨迹的可靠性优化设计

针对一般的平面连杆机构再现轨迹优化设计中一些不足之处,本文认为设计过程中应当同时考虑制造过程中公差给机构输出偏差带来的影响,在一般优化设计方法的基础上,本文运用可靠性设计的原理,建立了连杆机构可靠性优化设计的数学模型,为连杆机构再现轨迹的设计,提供了一个新的,更加合理的算法。     

φ1500热锯机连杆机构的轨迹精度分析

本文用解析法建立了热锯机连杆机构的运动方程，可精确计算连杆机构的轨迹偏差。提高了连杆机构的设计精度和热锯机的切削效率。     

基于剪式连杆机构撑套机械手的设计与分析

为了实现柔性硅胶隔离套能够沿预设轨迹自动撑开的功能,设计了一种基于剪式连杆机构的撑套机械手。对撑套机械手总体方案和剪式连杆机构进行设计研究,建立剪式连杆机构的运动学方程,进行撑爪杆质心运动轨迹仿真,并利用Adams仿真软件进行运动学分析。结果表明,设计的撑套机械手能够满足轨迹输出要求,撑套过程中无干涉现象且运行平稳,为下一步撑套机械手的优化设计奠定了基础。     

滚切剪曲柄连杆机构优化设计

介绍曲柄连杆机构对滚切剪的轨迹的影响、剪切时曲柄连杆机构的受力情况以及曲柄连杆的优化设计。     

用蒙特卡罗法进行轨迹创成连杆机构的稳健性分析

提出评判轨迹创成平面连杆机构设计稳健性的准则 ,并采用蒙特卡罗模拟方法对这类连杆机构的产品质量特性进行了分析 ,分析表明这类产品的质量特性不符合正态分布。     

混合驱动凸轮连杆机构的轨迹特性研究

介绍了混合驱动凸轮连杆机构的概念和意义，分析了混合驱动凸轮连杆机构的运动原理，推导出了计算公式。使用图解法对混合驱动的凸轮连杆机构的柔性空间作了分析，使用计算机仿真进行了验证，提出了轨迹设计原则。     

用齿轮连杆机构实现“8”字形轨迹研究

实现"8"字形轨迹曲线的机构设计问题在工程中具有一定的实际应用意义和理论研究价值.本文研究了齿连杆机构的参数变化对实现"8"字形轨迹曲线的影响.以仿鹰蛾微扑翼驱动机构作为应用实例,说明了齿轮连杆机构的设计方法.     

平面连杆机构轨迹综合的自相关法

提出了利用连杆轨迹曲线的自相关变换进行平面连杆机构轨迹综合的计算机方法。用该方法建立了已知连杆机构的轨迹曲线的特征参数数据库，从而可以在已建立的数据库中快速地查找出能够实现给定轨迹的连杆机构，以达到近似实现多点轨迹曲线的机构综合．     

阔幅喷气织机活动喷嘴机构的最优化设计

本文以空间连杆机构的近代运动理论和最优化设计理论为基础，讨论了阔幅喷气织机活动喷嘴空间连杆机构的最优化设计，并在微型计算机上对该机构进行了运动分析和最优化设计计算。从设计结果看，改进设计后机构所能实现的轨迹与期望轨迹十分接近，能满足设计要求。同时，由于在设计过程中考虑了原来的机构参数，使机构的改造也较容易实现。这种设计方法具有精度高、适应性强的特点，也可用于其它机构的设计。     

Minimal Realization of Linear Graph Models for Multi-physics Systems

An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...     

Quantum Cooperative Robotics and Autonomy

The intersection of Quantum Technologies and Robotics Autonomy is explored in the present paper.The two areas are brought together in establishing an interdisci...     

On the Relation of Load to Average Gap in the Contact Between Surfaces with Longitudinal Roughness

A computer simulation model for the contact between longitudinally-oriented rough surfaces has been formulated. This model closely duplicates the actual surf ace contact deformation behavior by taking into account the elastic interactions between the asperities. There were no assumptions made about the shapes, or any deformation behavior of the asperities, except for their obeying the laws of elasticity. The plastic deformations on the high asperity peaks were taken into account by setting a ceiling on their contact pressures at the material hardness value. The simulations used real surface profiles which were digitized from unworn circumferentially ground steel surfaces. Each pair of these profiles was mathematically combined to form an equivalent rough profile pressing against an infinitely rigid flat and having the appropriately adjusted elastic modulus. A total of 28 different pairs of profiles were used in the simulations. Each contacting pair was subjected to 30 different load levels and the local contact pressures and deformations were calculated. The contact simulations yielded some important mathematical relationships between parameters, such as the real area of contact, average gap, and average asperity load through statistical curve fitting. Two analytical functions were generated to relate the average load to average gap and the real area of contact to load.     

三绕组变压器的双绕组等效建模及在Matpower中的应用

针对实际电网存在着大量的三绕组变压器,但国际上一些著名商业软件,如BPA仿真软件、Matpower这一权威潮流计算开源软件,均只提供双绕组变压器模型,限制了其在具有三绕组变压器的电力系统中的应用的问题,潮流计算是自主开发的电力系统各种应用软件的核心模块,因此依托国际权威开源程序进行二次开发,是一种较好的选择。对Matpower要求的数据格式进行了归纳,对变压器的一般的等值电路及带理想变压器的等值电路和带标幺值的等值电路进行了分析研究,提出了三绕组变压器转换为双绕组等效模型的建模方法,使得原先只适应双绕组变压器的潮流计算软件可以适用于三绕组变压器电网的潮流计算;最后以Matpower软件为例进行了案例计算,并用PSASP仿真软件进行对比验证。研究结果证明,所提出的建模方法是有效的。     

考虑进油孔有限长滑动轴承油膜力的近似解析解

针对具有进油孔的有限长滑动轴承油膜力求解问题,采用变分原理和分离变量法,求得了有限长滑动轴承油膜压力分布的近似解析表达式。将油膜压力分布的近似解析表达式在油膜存在区域上进行积分,即得到了油膜力。将提出的计算有限长滑动轴承油膜力方法与无限长轴承模型、有限元方法的计算结果进行了比较,发现了提出的方法与有限元方法的计算结果很接近。最后,研究了进油孔位置和进油压力对油膜存在区域、油膜力等的影响,研究结果表明进油孔位置和进油压力对油膜存在区域和油膜力有较大的影响。     

电站锅炉模糊风险评价方法研究与应用

针对电站锅炉风险等级评价问题,将模糊综合评价技术应用到电站锅炉风险等级评价中。开展了电站锅炉失效影响因素及模糊评价因素的重要程度分析,建立了一套科学合理适于在线评价的电站锅炉风险评价体系,提出了模糊综合评价技术与改进的模糊层次分析法相结合的模糊风险评价方法,利用改进的模糊层次分析法计算了指标体系中各层指标权重。对某一台电站锅炉的实际运行工况影响子因素进行了模糊风险评价,采用模糊合成算子进行模糊综合运算得到电了站锅炉运行工况影响子因素的评价向量。研究结果表明:电站锅炉的运行工况影响子因素的风险评价等级为第6级,失效可能性等级为小,该电站锅炉运行工况良好。     

INTEGRAL EQUATION METHOD＇S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES

The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress fimction. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value.     

交通荷载作用下桥梁结构参数识别方法

应用动力节点加载法,将作用在桥梁上的交通荷载转化为等效节点荷载,再用两步构造法识别结构物理参数.第1步,用Newmark-β方法变换结构运动方程,并用结构的加速度响应求得变换空间内的位移、速度和加速度响应;第2步,基于最小二乘原理,构造出变换空间内求解结构参数的递推式,进行结构物理参数识别.数值模拟结果表明,在交通荷载作用下,该方法能够快速、准确地进行桥梁结构参数识别.     

Non-monotonic material contrast in scanning ion and scanning electron images

30 keV Ga⁺ focused ion beam induced secondary electron (iSE) imaging was used to determine the relative contrast between several materials. The iSE signal compared from C, Si, Al, Ti, Cr, Ni, Cu, Mo, Ag, and W metal layers does not decrease with an increase in target atomic number Z₂, and shows a non-monotonic relationship between contrast and Z₂. The non-monotonic relationship is attributed to periodic fluctuations of the stopping power and sputter yield inherent to the ion–solid interactions. In addition, material contrast from electron-induced secondary electron (eSE) and backscattered electron (BSE) images using scanning electron microscopy (SEM) also shows non-monotonic contrast as a function of Z₂, following the periodic behavior of the stopping power for electron–solid interactions. A comparison of the iSE and eSE results shows similar relative contrast between the metal layers, and not complementary contrast as conventionally understood. These similarities in the contrast behavior can be attributed to similarities in the periodic and non-monotonic function defined by incident particle–solid interaction theory.     

Short-Term Relay Quality Prediction Algorithm Based on Long and Short-Term Memory

The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar...