基于ADAMS与Solid Edge的摆杆凸轮机构设计

基于ADAMS与Solid Edge平台,对某机器的摆动滚子盘形凸轮机构进行设计,得到了凸轮的理论轮廓和工作轮廓,并建立了仿真模型,完成了设计和仿真的全过程。这是对以往作者研究摆杆凸轮较少的补充,也为其他摆杆凸轮机构的设计提供了一种新的、通用的方法。     

平面凸轮机构与平面四杆机构压力角特性相似性研究

本文根据高副低代的原理 ,将盘形凸轮机构演化为四杆机构 ,并证明该凸轮机构最大压力角与瞬时四杆机构最大压力角位置相似 ,为按四杆机构设计方法来设计凸轮机构提供一定的依据     

变等效摆杆长度摆动双滚子从动件盘形凸轮解析设计法

对于一般的摆动滚子从动件凸轮机构来说,摆杆是一根刚性直杆件,且摆杆长度是固定的,因此,采用反转法解析设计凸轮轮廓相对来说比较容易。而本文中所涉及的凸轮机构中,摆杆的结构形状不规则,且摆杆中心与从动件滚子中心之间的距离随凸轮转角不断发生变化,这就使得应用反转法求解凸轮轮廓时变得复杂。为了解决这个问题,介绍了摆动双滚子从动件盘形凸轮机构的结构和特点,提出了等效摆杆的概念,用几何学的方法求解得到等效摆杆长度的表达式,再通过反转法原理来设计凸轮轮廓曲线。对同类型机构中的凸轮轮廓曲线的设计有重要的参考价值和指导意义。     

平面凸轮机构速度分析的杆组方法

本文提出了平面盘形凸轮机构速度反求的杆组方法.该方法先将凸轮机构反转,然后将从动件与原机架视为Ⅱ级杆组,利用机构的速度瞬心原理结合杆组分析方法即可求得凸轮从动件速度与凸轮转角关系.这一方法将凸轮机构的分析转化为连杆机构的分析,可用于各种从动件的平面盘形凸轮机构的运动分析.     

平面凸轮机构位移反求的杆组方法

本文提出了尖底从动件盘形凸轮机构位移反求的杆组方法.该方法先将凸轮机构反转,然后将从动件与原机架视为Ⅱ级杆组,利用杆组分析求得凸轮从动件位移与凸轮转角关系的精确解.     

软管灌装封尾机的灌装机构设计与分析

以软管灌装封尾机的灌装机构为研究对象,对其摆杆凸轮机构、膏体灌装机构等核心部件的设计进行详细剖析。并对摆杆凸轮机构的工作原理进一步阐述,根据摆杆凸轮机构的各杆长关系,利用Matlab软件对摆杆凸轮轮廓曲线进行编程拟合,再利用Inventor三维建模软件对摆杆凸轮进行建模,对比分析Matlab与Inventor动力学仿真得到的摆杆凸轮轮廓曲线以及压力角变化等参数。同时对比分析国内外膏体灌注机构的灌装精度,对其结构设计进行详细阐述。最后通过对摆杆凸轮各参数的对比分析,验证了摆杆凸轮机构设计的可靠性与正确性,同时对膏体灌装机构的设计提出了设计的思路与方法。对软管灌装封尾机灌装机构进行设计,提升设备的运行速度、稳定性及灌装精度等性能。     

平面五杆机构双曲柄存在的充要条件研究

从五杆机构的装配条件出发,研究五杆机构双曲柄存在的充要条件,完整提出五杆机构双曲柄存在的充分条件,分析了研究五杆机构双曲柄存在必要条件的必要性,并建立了研究必要条件的一般方法。给出了lBD的极值与杆长和两个输入运动规律之间的通用关系式,并进行了数值计算验证结论的正确性。对五杆机构的设计和分析具有指导意义。     

爱控平面五杆机构轨迹实验台的设计

介绍了受控平面五杆机构轨迹实验台的总体系统设计 ,通过受控平面五杆机构轨迹实验台的合理设计 ,以保证受控平面五杆机构轨迹实验台的正常制造。     

最小尺寸摆动从动杆球面凸轮机构的设计方法

从压力角表达式出发 ,构造起相应的类速度图 ,解决了按许用压力角设计最小尺寸摆动从动杆球面凸轮机构的问题。文章将这种方法应用于力锁合凸轮和槽道凸轮     

可调四杆函数发生器的综合

介绍了利用多自由度五杆机构综合四杆可调函数发生器的方法。它可在不改变四杆机构活动构件尺寸的条件下,通过变动五杆机构一连架杆的角位置对所发生的函数进行调整,使四杆机构两连架杆转角在机架两种安装相位下实现两个给定的函数关系。     

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...     

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.     

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.     

Application of Feature Extraction through Convolution Neural Networks and SVM Classifier for Robust Grading of Apples

This paper proposes a novel grading method of apples,in an automated grading device that uses convolutional neural networks to extract the size,color,texture,an...     

分布动态载荷识别的抗噪处理

针对正交多项式频域法在用多种响应对矩形薄板进行载荷识别中抗噪性较差的问题,综合运用平均法、矩阵预处理和奇异值截断法等方法对之进行改善,并引入空间映射的思想,将该方法的应用范围拓展为复杂的模型.利用仿真算例,证实了该方法具有较好的抗噪性.     

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...     

End-to-End Multiview Gesture Recognition for Autonomous Car Parking System

The use of hand gestures can be the most intuitive human-machine interaction medium.The early approaches for hand gesture recognition used device-based methods....     

基于MELTAC-N平台的核电厂安全级DCS环网研究与测试

针对工程实践中环网通讯相关问题的处理缺乏理论基础及国产化安全级DCS平台的开发缺乏成熟经验借鉴问题,对基于MELTAC-N平台核电厂安全级DCS环网的软硬件实现进行了研究。提出了安全级DCS环网双环网冗余设计、光切换开关设计等硬件设计方法,以及以RPR协议为基础,采用全数据收发策略的软件设计方法。在CPR1000安全级DCS平台上对安全级DCS环网的可靠性及实时性进行了评价,并进行了容错能力、响应时间及响应时间稳定性测试验证实验。结果表明,基于MELTAC-N平台安全级DCS环网软硬件设计具有较好的容错能力及响应时间稳定性。     

The laboratory simulation of abrasive wear

Abrasive wear has long been recognised as one of the most potentially serious tribological problems facing the operators of many types of plant and machinery; several industrial surveys have indicated that wear by abrasion can be responsible for more than 50% of unscheduled machine and plant stoppages. Locating the operating point of a tribological contact in an appropriate operational ‚map’︁ can provide a useful guide to the likely nature and origins of the surface degradation experienced in use, though care must be exercised in choosing the most suitable parameters for the axes of the plot. Laboratory testing of materials and simulations of machine contacts are carried out for a number of purposes; at one level for the very practical aims of ranking candidate materials or surface hardening treatments in order of their wear resistance, or in an attempt to predict wear lives under field conditions. More fundamentally, tests may be aimed at elucidating the essential physical mechanisms of surface damage and loss, with the longer term aim of building an analytical and predictive model of the wear process itself. In many cases, component surface damage is brought about by the ingress of hard, particulate matter into machine bearing or sealing clearances. These may be running dry although, more usually, a lubricant or service fluid is present at the interface. A number of standardised wear test geometries and procedures have been established for both two- and three-body wear situations, and these are briefly described. Although abrasive wear is often modelled as following an ‚Archard’︁ equation (i.e. a linear increase in material loss with both load and time, and an inverse dependence on specimen hardness) both industrial experience and laboratory tests of particularly lubricated contacts show that this is not always the case: increasing the hardness differential in an abrasively contaminated lubricated pair may not always reduce the rate of damage to the harder surface.     

ANGULAR DISTORTION ALLOWABLE VALUE AND ASSESS METHOD OF WELD ON COKE TOWER

A graph as the new engineering method for estimate the safety of bulging deformation of coke tower is proposed. Through stresses analysis of circumferential weld of coke tower and comparing the stresses produced by pressure with heat stress of steady state, residual stress, bending stress produced by both itself weight and wind loads, it showed that the stresses produced by pressure on the angle distortion are the main factor of equivalent stress of the combined stress. After comparing four kinds of stress controlling conditions, the relation to stress with depth of angular distortion, grade of curvature of angular distortion and half of region of angular distortion has been inferred. Graph of deformation allowable value of coke tower for different condition by angular distortion and half of region of angular distortion has been plotted. The five steps for its engineering use have been explained. The lighter the grade of curvature is, the larger of bulge allowance, may be, and the bigger of depth of angular distortion may pose too. For the coke tower with a popular structure of Dg 5 400 mm×28 mm, the result by graph is nearly more than the result of two formulas formed by other research, the error is less than 7.0%. But, the graph can be easily applied to different size of angular distortion.