N型少齿差行星减速器动力学仿真研究

基于多体系统动力学理论,在ADAMS软件中建立了N型少齿差行星减速器的动力学模型,对其进行了动力学仿真,揭示了运行过程中少齿差行星减速器主要部件的运动情况,直观描述了齿轮内啮合接触过程中啮合力在时域和频域上的动态变化规律,揭示了齿轮内啮合传动过程中啮合冲击引起的输出轴转速及轮齿间啮合力的周期性波动,并且将理论结果和仿真结果进行了比较;研究结果为少齿差行星减速器的设计提供了参考和依据。     

微型行星少齿数齿轮减速器设计与动力学分析

以微型行星少齿数齿轮减速器为研究对象,设计了结构传动方案与正确啮合的齿轮参数,计算出理论传动比与输出转速,并利用三维软件Creo建立整个减速器实体模型,基于ADAMS建立了减速器的虚拟样机模型,进行了动力学仿真,仿真得到减速器输出轴转速和传动比,啮合接触作用力时域和频域的参数曲线以及减速器的转动频率,仿真结果与理论值吻合,为微型行星齿轮减速器动态特性研究提供了重要参考。     

基于ADAMS的抽油机用新型少齿差减速器动力学仿真分析

以肖南平先生提出并获得发明专利的一种抽油机用新型少齿差行星减速器结构所制造的试验样机为研究对象,利用软件Solid Works建立此减速器三维实体模型,将其导入到机械系统动力学仿真软件ADAMS中,从而建立起此减速器的虚拟样机模型。利用ADAMS软件对此减速器输入轴和输出轴的角速度进行仿真和计算,得出各齿轮副啮合力随时间的变化规律,验证了虚拟样机模型的正确性。并将仿真结果与计算所得结果进行对比,发现因行星轮偏心而引起的惯性力对齿轮副啮合力数值影响较小。也为精确计算齿轮副强度以及接触应力提供了数据支持。     

少齿差行星减速器动力学仿真分析

介绍了少齿差减速器的结构和转动原理,对其转速和啮合力进行了理论计算。运用ADAMS软件对少齿差减速器进行了运动学仿真,仿真结果显示,双联齿轮和输出齿轮的转速及减速器的传动比与理论计算结果相吻合,从而验证了模型的正确性。采用ABAQUS软件对减速器进行动态接触仿真分析,仿真结果显示,接触齿对的啮合力与理论计算结果误差在7%以内,进一步分析了在动态啮合过程中不同载荷对轮齿啮合力和接触面积的影响。同时,研究了齿轮在额定载荷作用下,轮齿实际接触齿数以及载荷的分配,为减速器动力学分析和工程应用提供依据。     

少齿差行星齿轮传动多齿弹性啮合效应的研究

采用有限元分析方法,使用ANSYS Workbench建立了少齿差行星减速器的参数化接触模型。对少齿差行星减速器进行静力学接触分析,分析结果表明,少齿差行星齿轮在传动过程中齿对存在弹性变形,从而出现多齿弹性啮合现象;并得到了在不同转矩下,少齿差行星齿轮传动的实际接触齿对数及各齿间载荷分配规律;分析计算结果为提高少齿差行星齿轮传动的承载能力、齿轮几何参数的优化设计及零部件的强度分析具有重大意义。进行少齿差齿轮传动的多齿弹性啮合效应的研究,对齿轮传动的承载能力的估算,降低制造成本,减小整机和齿轮尺寸,也有很重要的意义。利用有限元软件Ansys对少齿差行星减速器进行分析得到了减速器传动过程中的实际接触齿对数及各齿间载荷分配。     

渐开线少齿差行星齿轮减速器动态接触仿真分析

首先通过SolidWorks建立了渐开线五齿差行星齿轮减速器的三维模型,运用ABAQUS有限元软件对齿轮副进行了在额定工况下的动态接触仿真分析,得到轮齿从进入啮合到退出啮合全过程的动态啮合效果,得到了啮合时轮齿的接触应力和von-mises等效应力;仿真分析了渐开线少齿差行星减速器在不同载荷下的重合度,并得出了其单齿啮合刚度曲线,根据线性叠加原理,得出了渐开线少齿差行星减速器在额定载荷作用下的时变啮合刚度曲线。     

基于Pro/E和ADAMS的行星减速器动力学仿真研究

介绍了行星齿轮减速器虚拟样机设计流程,通过Pro/E软件对行星齿轮系进行了参数化建模。基于Hertz接触理论,利用ADAMS软件对其虚拟样机进行了动力学仿真,仿真结果表明,行星轴平均受力及行星轮啮合力与理论值相比,平均误差分别为0.21%和2.4%,验证了仿真结果的准确性,并得到了行星轴及行星轮最小设计安全系数,为行星齿轮减速器的优化设计提供了参考依据。     

电动车轮毂电机行星齿轮减速器均载性能分析

针对轮毂电机中浮动式行星齿轮减速器建立了浮动行星齿轮传动系统的动力学方程,并推导了均载系数的计算公式。利用ADAMS对太阳轮和内齿圈与各行星轮之间的动态接触力进行仿真,并对比分析了不同浮动结构类型对行星齿轮系统内外啮合副的均载性能的影响。仿真结果表明,双浮动类型行星齿轮系统的行星轮啮合力分布更均匀,运行过程中较少出现波动和突变;其均载系数最小,均载性能明显优于无浮动和单浮动结构的行星齿轮;研究结果为行星齿轮减速器的选型及其均载设计提供支持。     

基于ADAMS的齿轮减速器动力学仿真与故障分析

利用三维CAD软件Solid Edge为基础构建了二级齿轮减速器的三维参数化模型,将建立好的模型导入机械系统动力学仿真软件ADAMS中,建立减速器的多体动力学模型。将模型进行仿真,得到角速度、齿轮啮合力等参数特性曲线.将仿真结果与理论计算值进行对比,角速度数据误差很小,证明所用的仿真方法及参数取值的正确性;利用Solid Edge对中速轴大齿轮做断齿处理,并对正常齿轮减速器与断齿故障齿轮减速器仿真结果对比分析,得出故障齿轮的质心位置偏移以及啮合力周期性变化关系结论,为减速器进一步故障诊断提供了理论依据。     

渐开线2K-V型行星传动的结构设计及接触仿真

采用渐开线齿轮替代RV传动中的摆线针齿,重新设计了一款渐开线2K-V型行星减速器,并建立了减速器的三维实体模型;运用ABAQUS有限元软件对减速器关键的第二级内啮合进行静力接触仿真分析,得到轮齿啮合齿对数和载荷分配情况,与理论计算结果进行了对比,并进一步比较了不同转矩作用下的接触载荷与多齿弹性啮合效应系数;最后,考虑了实际工况中齿轮接触摩擦生热的影响,进行了额定转矩下的力热耦合稳态接触仿真,得到各轮齿的温度场分布与齿轮副的热应力情况,验证了减速器的接触特性。     

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.     

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。     

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....     

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.