圆柱螺旋弹簧的计算机辅助设计

计算机辅助设计为圆柱螺旋弹簧的设计提供了一种快速、合理、有效的方法。这种方法的关键是选取较合理的弹簧参数,分析弹簧特性,确定最佳的弹簧零件工作图。这样,圆柱螺旋弹簧的计算机辅助设计可归结为如下三步:一是对圆柱螺旋弹簧参数的优化;二是根据国家标准,进行弹簧特性分析;三是绘制弹簧的零件工作图。     

一种基于行为建模技术的弹簧优化设计新方法

将基本结构参数作为弹簧的设计变量,优化目标为弹簧的最小质量,设计约束条件包括强度、刚度、稳定性等要求,建立了圆柱螺旋弹簧优化设计的模型.采用行为建模方法设置优化参数并建立分析特征,对机械弹簧进行优化设计,方便快速地获得了符合设计要求且质量最小的弹簧,为弹簧的优化设计提供了一种新的途径与方法.     

圆柱螺旋弹簧CAD

本文以圆柱螺旋弹簧的重量最小、体积最轻为优化目标进行设计,在此基础上形成完整的圆柱螺旋弹簧CAD软件,其中包括特征参数的提取、物理参数和结构参数的计算、校验、工程图绘制等内容。另外本文还以弹簧为你阐述了机械零件CAD中所涉及到某些具体技术问题的处理方法。     

变刚度圆柱螺旋弹簧多目标优化设计及参数化实体建模

结合现有的弹簧设计理论及MATLAB优化工具箱的优化功能,利用VB定制界面实现弹簧已知参数的输入与管理,调用在MATLAB中开发的优化程序实现了变刚度圆柱螺旋弹簧质量最轻的同时安全系数最大的多目标优化设计。优化得到的弹簧参数保存至文本文件,由VB管理并传递至UG,使用UG/Grip二次开发实现该弹簧的参数化实体建模,为后续分析提供条件。     

定力矩扳手圆柱螺旋弹簧的强度可靠性设计

提出了对圆柱螺旋弹簧进行强度可靠性计算的公式及其置信度的分析,并详细介绍定力矩扳手的圆柱弹簧的可靠性设计的应用。通过对弹簧可靠度的计算,可以优化该弹簧的参数,进而确保定力矩扳手的优化设计。     

基于SolidWorks的圆柱螺旋弹簧的优化设计

基于SolidWorks有限元分析软件,在满足性能、强度、尺寸等条件要求的约束下,使用全局变量和方程式功能对圆柱螺旋弹簧进行完全参数化优化设计,结合有关弹簧的基本理论对结果进行验证,表明该方法具有可靠的精度,可作为弹簧设计的参考。     

多段式组合变刚度悬架螺旋弹簧设计与研究

针对某特种车辆悬架不同工况载荷特点,设计1种变刚度悬架螺旋弹簧。基于弹簧串联和并圈理论,提出多段式组合变刚度悬架螺旋弹簧设计方法,取各段弹簧丝径、工作圈数和弹簧内径为设计变量,以弹簧装配尺寸、变形量、总工作圈数、疲劳强度为约束条件,建立以弹簧质量最小为优化目标的数学模型,利用多变量优化设计方法,求解各段弹簧结构参数。结合仿真分析,能够满足最大变形量、最大剪切应力和疲劳寿命的要求,结果表明设计参数合理,方法可行。所提出的弹簧参数优化算法及弹簧设计方法为变刚度弹簧设计提供理论依据。     

预应力圆柱螺旋弹簧弯曲弹性特性研究

研究了预应力圆柱螺旋弹簧的弯曲弹性变形特性.通过对弹簧圈进行受力分析,利用材料力学的相关理论,推导了弹簧在受到弯矩作用时弯矩与弯曲角度之间的关系,得出了弹簧弯曲角度的计算公式,并对参数进行了优化.通过试验验证,表明所提出的公式精度较高,能满足工程设计的需要,为后续弹簧系统的动力学性能研究奠定了基础,同时也为新弹簧的设计提供了一定的理论依据.     

圆柱形拉伸螺旋弹簧的相似系列设计

采用相似设计理论,探讨了圆柱拉伸螺旋弹簧的相似系列设计,从而获得了拉伸弹簧的几何尺寸和受力、变形相似的系列产品参数。     

150吨拖揽机刹车系统圆柱螺旋弹簧设计与制造

通过优化设计实现了150吨拖揽机刹车系统弹簧由蝶形弹簧改为圆柱螺旋弹簧的改形设计与制造。     

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.