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外文出处：Prasan Kumar Sahoo著,Proc of Computing, and Communications Conference, 2005.[C]出版社：IEEE，2005年附件：1.外文资料翻译译文；2.外文原文基于拓扑结构的分布式无线传感器网络的功率控制摘要无线传感器网络由大量的传感器节点电池供电,限制在一定区域内的随机部署的几个应用。
由于传感器能量资源的有限,他们中的每一个都应该减少能源消耗,延长网络的生命周期。
在这篇文章中,一种分布式算法的基础上,提出了无线传感器网络的构建一种高效率能源树结构,而无需定位信息的节点。
节点的能量守恒是由传输功率控制完成的。
除此之外,维护的网络拓扑结构由于能源短缺的节点也提出了协议。
仿真结果表明,我们的分布式协议可以达到类似集中算法的理想水平的能量守恒，可以延长网络的生命周期比其他没有任何功率控制的分布式算法。
关键词：无线网络传感器，分布式算法，功率控制，拓扑结构1.引言近年来在硬件和软件的无线网络技术的发展,使小尺寸、低功耗、低成本、多功能传感器节点[1]的基础上,由传感、数据处理及无线通信组件组成。
这些低能量节点的电池,部署在数百到成千上万的无线传感器网络。
在无线传感器网络系统、音视频信号处理系统,使用更高的发射功率和转发数据包相似的路径是种主要消费传感器的能量。
除此之外,补充能量的电池更换和充电几百节点上的传感器网络应用的大部分地区,特别是在严酷的环境是非常困难的,有时不可行。
因此,节能[2],[3],[4]的传感器节点是一个关键问题,如传感器网络的生命周期的完全取决于耐久性的电池。
传感器节点一般都是自组织建立了无线传感器网络,监察活动的目标和报告的事件或信息多跳中的基站。
有四种主要的报告模式的传感器网络:事件驱动、队列驱动、期刊、查询和混合的报告。
在事件驱动模型,节点报告接收器,同时报告遥感一些事件,例如火灾或水灾而敲响了警钟。
定期报告中,节点模型的数据收集和可聚合所需资料,成为集,然后定期的发送到上游。
关于拓扑优化1. 基本概念拓扑优化是结构优化的一种，结构优化可分为尺寸优化、形状优化、形貌优化和拓扑优化。
拓扑优化以材料分布为优化对象，通过拓扑优化，可以在均匀分布材料的设计空间中找到最佳的分布方案。
拓扑优化相对于尺寸优化和形状优化，具有更多的设计自由度，能够获得更大的设计空间，是结构优化最具发展前景的一个方面。
2. 发展起源拓扑优化的研究历史是从桁架结构开始的。
Maxwell 在1854年首次进行了应力约束下最小桁架的基本拓扑分析。
1904年Michell用解析分析的方法研究了应力约束、一个载荷作用下的结构，得到最优桁架缩影满足的条件，后称为Michell准则，并将符合Michell 准则的桁架称为Michell桁架，也称最小重量桁架，这是结构拓扑优化设计理论研究的一个里程碑。
但是，Michell提出的桁架理论只能用于单工况并依赖于选择适当的应变场，并不能用于工程实际。
直到1964年，Dom、Gomory、Greenberg等人提出基结构法，进一步将数值理论引入该领域，此后拓扑优化的研究重新活跃起来了。
所谓的基结构就是一个由众多构件联结而成的、包括所有载荷作用点、支撑点在内的结构。
Michell桁架理论在近几十年得到了重要的进展。
Cox证明了Michell的桁架同时也是最小柔度设计。
Hegemier等将Michell准则推广到刚度、动力参数约束，以及非线性弹性等情况。
Hemp纠正了其中的一些错误。
Rozvany对MIchell桁架的唯一性和杆件的正交性进行了讨论，对Michell准则做了进一步的修正。
现在，已经建立了多工况以及应力和位移组合约束情况的优化准则。
Dobbs和Fetton使用最速下降法求解多工况应力约束下桁架结构的拓扑优化。
Shen和Schmidt采用分枝定界法求解在应力和位移两类约束下桁架结构在多工况作用下的最优拓扑。
王光远等提出了结构拓扑优化的两相法。
Kirsch针对离散结构的拓扑优化问题提出了一种两阶段算法。
拓扑优化技术在汽车减速器壳体设计中的应用刘明卓北京汽车股份有限公司汽车工程研究院，北京 100021摘要：汽车减速器壳体是汽车底盘的重要部件之一。
主流减速器壳体多采用球墨铸铁材料，设计相对保守，其重量相对较重，迫切需要通过拓扑优化设计减少其重量。
本文论述了减速器壳体结构优化的意义，并针对球墨铸铁材料减速器壳体的受载状况，利用OptiStruct软件探讨一种有效的减速器壳体拓扑优化设计方法，减少自重并提高了壳体的综合力学性能。
关键字：拓扑优化, OptiStruct，减重0.引 言绿色环保理念的提出以及激烈的市场竞争，使得每一个汽车主机厂商面临降低设计成本和设计轻量化性能最优化的考验。
众多汽车厂商都把汽车结构最优化设计放在一个空前的高度，并大范围的采用结构优化工具来解决低成本、高性能、轻量化这三个矛盾。
球墨铸铁减速器壳体作为汽车上最重要的零件之一，其自身重量较重，迫切需要通过拓扑优化设计减轻自重提高力学性能，降低生产成本。
由于球墨铸铁减速器壳体结构复杂，承载多变，力学性能要求较高，因此在优化设计中存在一定的难度。
OptiStruct作为一个非常有效的结构优化工具，被广泛应用于航空航天、汽车等领域，并得到验证。
本文采用OptiStruct来研究汽车减速器壳体的优化设计问题，探讨一种有效的优化设计方法，达到减少自重并提高壳体综合力学性能的效果。
1.汽车减速器壳体结构拓扑优化意义汽车减速器的结构形式因齿轮类型、主动齿轮与从动齿轮的安装方法以及减速形式而异，而减速形式可分为单级减速、双极减速、双速减速、单双级贯通、单双级减速配以轮边减速等[1]，减速器结构与工况复杂多变。
在传统设计模式中，车辆工程师对汽车减速器结构先凭经验进行设计，在设计分析之后再修改原设计进行减重。
传统设计的缺点是，在修改零件设计之后，零件无法满足刚度和强度等设计要求，同时反复修改设计花费大量的时间，也增加人力和计算的成本。
拓扑优化的好处是，在设计初始阶段就尽可能考虑各个设计指标，使得初始概念设计能基本满足设计要求，减少设计过程的反复迭代，缩短设计周期，并提高设计质量。
拓扑优化在桥梁支座轻量化设计中的应用韩家山;曹翁恺;顾海龙;陈新培【摘要】Taking the bridge bearing as the research object,based on the topology optimization design idea,the lightweight design of structure was carried out with the stiffness maximization of base plate as the design objective. Under the premise that the normal function of bearing was not affected,the bottom full constrained model and the bottom partial constrained model were defined.Two models corresponded to two different initial design areas.The bearings were optimized and analyzed separately.Through the topology optimization,the density contours of cylindrical-shrinkage type and the plate-hollow type were obtained.Based on the cylindrical-shrinkage type density contour,the base plate was rebuilt and the feasibility of topology optimization structure was verif ied.The research results indicate that under the premise of satisfying the performance requirements of bridge bearing,the weight of the bottom plate structure is reduced by 21.2%through the topology optimization of the bottom full constrained model. The results provide a new idea for the lightweight design of bridge bearing.%以桥梁支座为研究对象,基于拓扑优化设计思想,以支座下座板刚度最大化为设计目标对结构进行了轻量化设计.在保证支座正常功能不受影响的前提下,定义了底面全约束模型和底面非全约束模型,对应2种不同的初始设计区域,并分别对支座进行了优化分析.经过拓扑优化得到了外圆中缩式及底板中空式结构的密度图,再基于外圆中缩式密度图对下座板模型进行了二次构建,验证了拓扑优化结构的可行性.研究结果表明,在满足桥梁支座使用性能要求的前提下,底面全约束模型拓扑优化得到的支座下座板结构重量减小了21.2%,为桥梁支座的轻量化设计提供了一种新的思路.【期刊名称】《铁道建筑》【年(卷),期】2018(058)003【总页数】4页(P35-38)【关键词】桥梁支座;拓扑优化;数值计算;轻量化设计;下座板;刚度最大化【作者】韩家山;曹翁恺;顾海龙;陈新培【作者单位】洛阳双瑞特种装备有限公司,河南洛阳 471000;洛阳双瑞特种装备有限公司,河南洛阳 471000;洛阳双瑞特种装备有限公司,河南洛阳 471000;洛阳双瑞特种装备有限公司,河南洛阳 471000【正文语种】中文【中图分类】U443.36作为连接桥梁上下部结构的“关节”，桥梁支座可以将桥梁上部结构中反力和变形可靠地传递给桥梁下部结构，是桥梁结构中的一个重要组成部分[1]。
Redesign and Optimization of Lift Plate Based on Glass Installation LoadVeeranna B. SheelvanthArvinMeritor, Technical Support CenterBangalore, IndiaAbstractWith the automotive industry moving towards higher durability targets, reduced product development cycle time and lower design costs, the need for simulation has never been higher. This paper explains the use of optimization techniques in the design of a lift plate to reduce the weight and cost without compromising the functional requirements. A step-by-step approach to redesign the lift plate is proposed. As the glass insertion into the lift plate is one or two times in the lifetime of the lift plate, so fatigue life estimation was not considered. The scope of this paper is limited to optimization of lift plate using topology optimization capabilities available in OptiStruct.IntroductionLift Plate is a plastic component, which holds the glass in position and travels along the guide rail when passenger moves the glass up and down with power assistance. Lift Plate is a part of window regulator system, which is housed inside the car door system. Figure1 illustrates the window regulator with glass down position. Design of lift plate requires that it has to withstand target loads exerted when glass assembles onto it. The motivation to use simulation techniques is to redesign the lift plate field failure issues associated with preliminary designs. A lift plate experiences high structural stress states during an assembly event. In this paper it is proposed to use, topology optimization method using Optistruct, a linear structural solver. Optimization is a linear analysis method and does not include non-linear behavior in the model.GlassZLift PlateXFigure1: Window regulator Assembly with glass held in lift plate.ObjectiveArvinMeritor Door system experienced field failures of Lift Plates during the assembly of the glass for a particular door module. Since original design of the lift plate was for a door module, which had different glass width compared to the new door module, the re-designing of the lift plate was essential and (the) study has been carried out. Redesign of the lift plate considering the manufacturing feasibility was done with the help of Optistruct capabilities for the glass insertion loads, which was critical. Verification was done by ANSYS software to take care about the plastic non-linearity of the problem. The validation was carried out by conducting glass insertion test.In the process of redesigning, to reduce the cost of the product, the whole width of the lift plate has been reduced drastically without affecting the functional requirements. In addition to this, to reduce the number of components as well as number of operations during the assembly process of the glass on to lift plate, snap fit has been successfully replaced by push fit.Proposed Method EffectivenessAn effective Computer Aided Engineering (CAE) method must meet the following requirements:1. Feasible to implement2. Representative of the test3. Design Impact4. Cost EffectiveThe proposed method does! It has been used on multiple lift plate design and development programs at ArvinMeritor with good success.Feasibility / Test RepresentationIn our method and in this paper, we have identified some key elements that influence design of the lift plate. Keeping in mind the cost-payoff proposition, some process details that have a minor influence have been intentionally left out to make the implementation of the proposed method feasible. However, on the whole the simulation process is very much representative of the test procedure.Design ImpactLike any other simulation method, this has not been able to make a perfect correlation with test results. However, the direction provided by the topology optimization has always been effective to guide the design process. Lift plate designs driven by simulation results have always had a substantially higher level of performance compared to their baseline prototypes.Cost EffectiveThe proposed method has been very cost effective to derive multiple design proposals by applying the optimization capabilities. Time required for the model setup for the proposed method is about 2 man-days and based on the optimization direction, the modifications can be done within the HyperMesh very quickly. Computational time is about ½ an hour on a single CPU workstation. The simulation method has enabled Door Systems engineering team at ArvinMeritor to evaluate multiple lift plate design proposals before making a final choice.Lift Plate OverviewAssembly process of push fit type lift plate: First the threaded cable is inserted into the lift plate (just like a thread screw) and lift plate will be held in vertical position (as in the car door) with the tension in the cable, then the glass will be pressed against the lift plate manually and pins will be inserted to lock the glass in position.Assembly process of snap fit type lift plate: First the threaded cable is inserted into the lift plate (just like a thread screw) and lift plate will be held in vertical position. The glass will be pushed in to the lift plat forcefully so that it opens the snap and gets assembled / locked automatically. There is no further manual assembly operation.Nomenclature1. Push fit arrangement with pins in position.2. Threaded cable3. Cable holder4. Snap fit hook5. Tab6. Guides for the glass321546. Figure 3: Latest lift plate design with Snap fit type.Lift Plate Design Criteria• Lift Plate experiences glass assembly load.•Snap fit arrangement should deflect more than the glass thickness.Glass Assembly Loads :As explained by the words “Glass Assembly Loads”, loads refer to the loads experienced by the glass on lift plate when it is assembled. This is the load experienced by the plastic lift plate when the glass is forcefully thrusted upon that. Stress on the lift plate is one of the criteria; it should not go behind the yield strength of the material.Snap fit hook should deflect more than the glass thickness:When glass gets assembled on to the lift plate, first it gets contacted with the snap fit hook. Snap fit hook along with tab acts as cantilever beam and snap fit hook should deflect more than the thickness of the glass and then glass slides downward. There is a small hole provided in the glass with a diameter slightly more than the snap and then the glass gets locked automatically as soon as they get aligned together and tab along with snap fit hook will regain its original position.Fe Model SetupFigure 4 illustrates the boundary condition and the loads used in the whole simulations.Boundary ConditionsConsidering the assembly process of glass into the lift plate, the boundary condition is derived. During the glass assembly process, the lift plate will be at the glass down position suspended in the cable, which is under full tension. The inner surface of the cable holder constrained from both translation and rotation.15 lbs (65.5 N)Cable holder inner surface constrained in all DOF’sLoadingGlass insertion load of 15 lbs (65.5 N) was applied on the snap fit hook area as specified by the OEM. This value holds good for both optimization as well as validation.Figure 4: FE model with loads and boundary conditionsMaterial PropertiesAs Optistruct doesn’t support material non-linearity, linear material properties are considered for the optimization process with the below mentioned values.Young’s Modulus, E= 2600 MP a Poisson’s ratio, µ = 0.37Non-Linear material property of lift plate material is considered while validating the optimized design. The figure 5 illustrates the stress strain diagram of plastic material for the ambient temperature of 23° C .Figure 5: Non-linear material property of @ 23° CTopology OptimizationTopology optimization generates the optimal shape of a mechanical structure. The structural shape is generated within a pre-defined design space. In addition, the user provides structural supports and loads. Without any further decisions and guidance of the user, the method will form the structural shape there-by providing a first idea of an efficient geometry. Therefore, topology optimization is a much more flexible design tool and most widely used in automobile industries for the conceptual design.Post- Processing Analysis ResultsThe analysis results obtained from OptiStruct are post-processed with HyperWorks visualization and post-processing module - HyperView and the results are analyzed.Topology OptimizationOptimization was done in two stages. First stage is to address the issue of getting high stress at the top end of the tab and other very important one is at the bottom of the tab.1st Stage OptimizationAs glass directly hits on the top end of the tab, the area where glass hits should bestrong enough to withstand the loads exerted by the glass assembly. Sooptimization was carried out to find out the best design pattern on the backside ofthe tab top. Only the tab was considered as design space and rest of the lift platewas defined as non-design space. Design space is defined as total volumeavailable for the structural modifications. Based on the directions given by postprocessing results of optimization, ribs are modeled on the backside of the tabconsidering the manufacturing feasibility. The figure 6 shows the modified designat the backside of the tab top.Figure 62nd Stage OptimizationBottom of the tab experiences high stress as it acts as cantilever beam when tab hook experiences load. This is the area where the existing design of the lift plate failed during the glass assembly process. Again topology optimization technique was applied to find the exact design at, both the, front and backside of the tab bottom.Figure 9.Figure 10.Figure 7. Figure 8.Figure 7 and figure 8 shows the load transfer path on the front and backside of the tab bottom areas respectively. Figure 9 and Figure 10 shows the front and rear view of tab of the final design, which was arrived, based on the load transfer path.Again the same loads and boundary conditions are used in the optimization process as explained above are considered for the validation of optimized design. Stresses observed at the bottom of the tab as shown in the figure 11 and figure 12 below. Optistruct is used for the optimization and also to get to know the stress and displacements at the conceptual stages of the design as the analysis is based on linear assumptions. Since the lift plate is a plastic component, to take account of material non-linearity the final design validation is carried using ANSYS as a solver. Post processing is carried out in HyperView because of enhanced features and intuitive user interface.48*MPa49.8* MPaFigure 11: Front view of the lift plate Figure 12: Rear view of the lift plateThe glass installation is a once in a lifetime of the lift plate, so fatigue life calculations have not been done. The stress obtained at the base of the tab of 49.8*MP a is considered to be safer against the Yield strength of the lift plate material is~60*MP a.Figure 13 shows the displacement plot of the lift plate. When theglass gets assembled on to the lift plate, it contacts the snap fithook, so the displacement is 5.7* mm which is more than the glassthickness which is about 4.1*. So conclusion is that the optimizeddesign meets the second criteria and design is good as per theflexibility criteria.5.7* mmFigure 13: Displacement plotThe output options discussed in this section are only illustrative examples of results that can be post-processed. The analyst must determine and post-process the necessary outputs, depending on the goals of his analysis.Table: Results Summary# Design Analysis Load Case Displacementat snap fithook (mm)MinimumDisplacementRequiredVon-MisesStress(MPa)Weight of theLift plate(gms)Yield Strength(MPa)1 OptimizedDesign Material Non-Linear15 lbs * 5.7 * 4.1 * 49.83 * 73 * ~ 60 ** Magnitudes are just for reference, not the actual values.Benefits SummaryAs noted in the earlier sections, this approach reduces the product development costs by minimizing the number of expensive prototypes that need to be tested. Based on the directions given by Optimization, design changes can be quickly evaluated by changing the FE model that is correlated with test setup. This method not only minimizes product development time, but also offers a structurally optimized lift plate to the end customer. Another advantage of optimization method is that the toggle between preprocessor and the optimization process is very easy as it is in a single window of the HyperWorks. It facilitates the engineering team to study the response of the lift plate assembly process in detail. It is often difficult to study this in the test lab or in the assembly line because lift plate assembly is a very short event and simulation overcomes this problem. The results can be post-processed and viewed multiple times from different orientations to study the response of the lift plate for glass installation loads and as per the optimization directions, design can be changed till the safe stress value.ConclusionThe proposed simulation approach for glass assembly or insertion has proven to be an effective tool in the design / redesign and development of lift plate for the glass insertion load case.ACKNOWLEDGMENTSThe authors would like to acknowledge ArvinMeritor Door Systems Engineering team for all their support in designing and developing simulation methods for lift plate.REFERENCES[1]. Devadas Kumbla, Pan Shi and Joseph Saxon, “Simulation Methods for Door Module Design”.。
OptiStruct拓扑优化技术在飞机结构设计中的应用Application of Topology Optimization Technology OptiStruct in Designing of the Aircraft Structure郭琦(中航飞机西安飞机分公司，陕西西安，710089)【摘要】随着优化技术在飞机结构设计中的深入应用，传统的结构设计方法已发生了改变。
本文介绍了优化技术的设计理论和方法，运用有限元分析和优化工具OptiStruct对飞机某结构接头进行拓扑优化分析，并验证其强度和刚度都满足设计要求。
说明拓扑优化能在产品概念设计阶段寻求最佳的设计方案，对缩短产品设计研发周期和提高产品质量有着重要的意义。
关键词：有限元分析拓扑优化 OptiStruct 结构分析Abstract:w ith the further application of optimization technique in designing of the aircraft structure, the structure design method of traditional already change. This paper introduces the design theory and method of optimization Technology, use of the finite element analysis and optimization tool OptiStruct to topology optimization of a certain connector structure, and verify its strength and stiffness meet the design requirements. Explain the topology optimization is helpful to seek the best design scheme in the conceptual phase of products, and have important significance for reduce the product design cycle and improve the quality of products.Key words: Finite element analysis, Topology optimization, OptiStruct, Structure optimization1引言结构优化技术是当前CAE技术发展的一个热点，其已被广泛应用到各工业领域[1]。
基于OptiStruct的望远镜主框架拓扑优化设计Topologic Optimization Design of Telescope Main Frame Based on Optistruct马肇材1,2,陈华1,2，刘伟1MA Zhao-cai1,2, CHEN Hua1,2, LIU Wei1（1．中国科学院长春光学精密机械与物理研究所，吉林长春 130033；2.中国科学院研究生院，北京 100039）(1．Changchun Institute of Optics，Fine Mechanics and Physics，Chinese Academy of Sciences，Changchun 130033，China；2．Graduate School of the Chinese Academy of Sciences，Beijing100039，China)摘要：针对某航空望远镜主结构的重量过高的问题，提出了对航空相机望远镜主框架进行拓扑优化设计的方法。
基于拓扑优化理论，在重力过载的工况下对望远镜主框架拓扑优化，以整个框架作为设计变量，以框架的体积分数和固有频率作为约束条件，选结构的柔度最小化为目标函数，建立拓扑优化模型。
采用MSC.PATRAN/NASTRAN软件对航空望远镜拓扑优化结果进行仿真，分析结果表明，结构的重量减少了77％，结构静态刚度提高，动态刚度符合要求，温度变化环境下光学成像条件改善。
关键词：拓扑优化；刚度；航空望远镜中图分类号：V447.3 (V-航空航天) 文献标识码：AAbstract: In order to reduce the weight of an aerial telescope main structure, a topologic optimization design method of the aerial telescope main frame was presented. The telescope main frame with overloaded gravity was optimized based on topologic theory. The topologic optimization model takes the whole frame as variation, takes volume fraction and natural frequency as computing constrains, takes the maximal structure stiffness as the objective function. The resulted model was analyzed with MSC.PATRAN/NASTRAN software. The result indicated that the structure’s total weight was reduced 77%, the structure’s static stiffness increased, the dynamic stiffness was suitable and the optical imaging condition was improved.Key words: topologic optimization; stiffness; aerial telescope1 引言在航空相机概念设计阶段，为了保证航空相机能适应机载平台上复杂的工作环境（如冲击、振动、高低温变化、低气压等），有良好的成像质量，因此需要相机具有良好的结构刚度的同时也要保证相机反射镜具有良好的热稳定性[1]。
