微小卫星星敏感器支架的优化设计与试验

针对卫星结构中星敏感器支架在随机激励下加速度响应均方根(RMS)值过大的问题,提出了星敏感器支架优化设计方法。简述了星敏感器安装点随机响应的基本理论,对卫星结构进行了模态和加速度响应灵敏度分析。以星敏感器安装点RMS值最小为目标,以基频和体积分数为约束,建立了星敏感器支架随机响应优化模型,并对支架进行了拓扑优化设计。最后,利用MSC.PATRANNASTRAN对优化处理后的支架模型进行了工程分析。结果显示:星敏感器安装点随机响应RMS值降低了20%以上,支架结构轻量化率达到了50%。另外,利用振动试验台对支架进行了振动试验。实验显示:有限元分析结果与试验数据相对误差低于15%,表明设计的支架的性能参数满足设计指标,验证了所采用优化方法的可行性。     

基于有限元的液压支架强度可靠性的优化分析

利用ANSYS软件对型号为ZF8000/22/35的液压支架进行建模分析,计算可靠性其及其灵敏度.通过有限元分析,得出优化液压支架可靠性的方法,对液压支架结构进一步优化设计提供有力的数据参考.     

基于灵敏度分析的支架结构优化设计

车灯振动试验支架是车灯振动试验最重要的固定支架,其结构的合理性直接影响试验的准确性。文中以灵敏度分析为突破口,找出对支架动态特性最敏感的几个设计参数,随后对结构进行优化设计,为支架的改进设计提供参考。     

ZZ10000/17/35型支撑掩护式液压支架的优化与设计

以原支架为研究对象,根据相应煤矿生产要求,在计算机优化设计理论的基础上,对支架总体及各部件结构进行了优化计算和设计,重点对顶梁、掩护梁、底座进行结构优化设计。该设计优化改善了支架的受力状况、装配关系、结构性能,提高了支架的使用寿命。     

利用Pro/E的缆索检测机器人连接支架的优化设计

连接支架是斜拉桥缆索检测机器人中的关键部件,直接影响到斜拉桥缆索检测机器人工作过程中的安全性和可靠性.利用Pro/E软件建立了缆索检测机器人连接支架的三维模型,采用Pro/Mechanica模型分析软件对连接支架进行应力、应变和灵敏度分析.在确定了连接支架结构的重要设计参数后,以轻型化为目标,对连接支架进行了优化设计及仿真分析.仿真结果表明,优化后的连接支架在保证应力和应变符合要求的前提下,达到了减轻重量的优化设计目的,对检测机器人的整体优化研究具有重要意义.     

基于Workbench的电池组支架结构分析及优化

以混合动力汽车用电池组底部支架为例,建立了其三维有限元模型,利用有限元分析软件ANSYS Workbench对预设计底部支架进行静力学及动力学分析,并据此对底部支架进行结构改进,以在设计阶段预测其工作的性能,并为底部支架的结构优化设计提供理论依据。     

基于数值模拟方法的液压支架结构优化

基于CAE优化原理,采用数值模拟方法优化了液压支架的底座结构以及连杆机构尺寸。以底座的外主筋厚度,内主筋厚度以及底板厚度作为设计变量分别进行灵敏度分析,通过基于ANSYS的优化计算,将底座质量降低了5%,应力峰值降低了8%;以连杆机构的尺寸为设计变量,通过基于ADAMS的优化计算,降低了顶梁端点轨迹横向摆动,有效地提升了液压支架的支护效率。     

基于Pro/Mechanica的结构优化设计

介绍了Pro/Mechanica,并针对结构优化设计给出了具体设计步骤。以一扳手为例,在Mechanica模块下对其结构进行了灵敏度分析,通过灵敏度分析确定结构的重要设计参数,并以质量最小为目标函数,完成了结构的优化设计。研究表明利用Pro/Mechanica可以将设计和分析结合起来,实现智能设计,从而为解决其他复杂结构的优化分析提供了新途径。     

发动机悬置支架结构设计及强度分析

发动机悬置支架是汽车动力系统的关键结构部件之一,其强度和可靠性至关重要。文中以某型发动机悬置设计作为背景,通过对纵置发动机布置特点和设计空间的分析,运用三维数字化设计手段进行悬置支架结构设计。采用有限元法对所设计结构进行强度分析,以轻量化设计方法进行了改进和优化。分析结果表明,改进后支架的结构强度满足要求,并且减重14%,获得了良好的设计效果。     

基于有限元数字仿真平台的四向穿梭车换向支架结构优化与轻量化改进

因四向穿梭车的某零件力学性能不符合设计与轻量化要求,以四向穿梭车换向支架为分析与优化对象,利用数字仿真平台,对换向支架原设计结构进行应力、应变和模态分析,并从材料、结构设计和制造工艺方面进行改进和优化,再用该数字仿真平台对结构进行动静态特性分析,通过结构-材料一体轻量化设计的方法,大大提高了工作效率,降低了成本,其优化...     

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...     

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。     

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。     

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.     

Fifth International Summer School on Screw-Theory Based Methods in Robotics

正3-11 September,2014University of Bologna,Bologna,Italy www.summerscrews.org summerscrews2014.ing.unibo.it SUMMER 20SCREWS 14In 2014,our screw-theory school comes to the world's oldest university.In early September,Summer Screws'14 will gather six experts in the application of screw theory in robotics and up to 40 participants at the University of Bologna,Bologna,Italy.The school will teach attendees how to apply existing methods and empower them to develop new ones in their own research.The basic theoretical notions will be introduced in a rigorous manner,emphasizing examples,applications,and exercises.Scholarships are available.     

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。     

INDUSTRIAL ENGINEERING AND VISUALISATION-A PRODUCT DEVELOPMENT PERSPECTIVE

Taking the actual project of teaching and researching process for example, the relationship between the industrial engineering and product development is discussed. And use the novel visualization technology to support the industrial engineering and product development. How to use the new computer modeling and simulating technologies to support the product development and industrial engineering, is introduced especially. The support includes both domestic products and industrial systems. The visualization and computer technologies take a very important role in some system or multi-direction modeling, those technologies mentioned above can help the industrial engineers study the effect of design on the whole life circle, including the producing steps. So the engineers can avoid making the wrong decision which may cause bad effects on the whole industrial engineering.     

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...