麦弗逊式独立悬架运动分析

运用空间机构运动学方法建立某皮卡车麦弗逊式独立悬架的数学模型,给出其运动特性参数的计算方法.同时还应用ADAMS软件,建立同种悬架和转向系的多体运动学模型,对麦弗逊式悬架的运动进行仿真分析.采用两种方法计算、仿真结果的一致性表明这两种方法都是分析麦弗逊式悬架运动特性行之有效的方法.且使悬架的设计计算更为简单、准确、清晰,在实际应用中提高了工作效率.     

CATIA DMU在麦弗逊悬架运动学特性分析上的应用

麦弗逊式独立悬架以其结构紧凑、易于布置横置发动机、构件受力小等优点在现代轿车及轻型客车上得到广泛应用。文中基于CATIA DMU模块对麦弗逊式独立悬架进行了运动学分析，得出某款轿车麦弗逊悬架的运动学特性，为整车K＆amp;C对标及系统设计提供了依据；同时通过与K＆amp;C试验结果对比，验证了该方法在麦弗逊式等受弹性件影响较小的独立悬架运动学分析上的应用具有普遍的适用性。     

基于D-最优试验设计的麦弗逊悬架优化

汽车操纵稳定性和舒适性成为评价汽车性能的重要技术指标之一,而汽车操纵稳定性和舒适性都与汽车悬架性能密不可分.以麦弗逊式悬架为研究对象,结合D-最优试验设计理论,建立了汽车的麦弗逊独立悬架动力学模型.结合随机路面模型仿真,对悬架各个结构参数进行最优实验分析,得到麦弗逊式悬架优化性能参数.经过优化分析与优化前悬架的性能进行对比,得出最优结构参数.优化实验结果表明:优化后麦弗逊式悬架综合性能得到了进一步提升.     

基于ADAMS/Car的麦弗逊式悬架运动学和弹性运动学建模与仿真

利用多体系统动力学仿真软件ADAMS/Car模块建立麦弗逊式悬架模型,应用双轮同向激振仿真对麦弗逊式悬架进行运动学和弹性运动学仿真,将仿真结果进行对比.结果表明:弹性构件对车轮定位参数有明显的影响,可有效提高汽车操纵稳定性.     

基于麦弗逊式前悬架特征的整车架构开发研究

整车的操稳性、驾驶平顺性和轮胎的使用寿命直接受悬架系统的运动学特征影响,当进行整车架构开发时,工程师们更需要综合考虑多项指标跨车型的适应性.本文根据麦弗逊悬架系统的结构特点及其约束条件,确定几何参数及其变化规律,并运用VC++软件进行麦弗逊式前悬架特性参数的计算及运动学分析,同时结合NX UG参数化建模的方法进行动态的空间校核.该方法能够提高设计优化效率,由此能够实现多个车型下前悬架系统的同步设计开发,对实际的工程应用具有较高的价值.     

汽车悬架系统的运动仿真及优化设计

针对某微型电动汽车的麦弗逊式独立前悬架系统,利用ADAMS/Car建立了虚拟样机仿真模型,对悬架的几何参数和车轮的定位参数进行了分析,并利用ADAMS/Insight模块,以悬架的前束角、车轮外倾角和主销后倾角为目标对悬架进行了优化设计。通过运动仿真掌握了悬架的运动学规律及运动学特性,为悬架优化提供了有效的数据支持;优化使车轮定位参数在跳动过程中的变化量处于更合理的范围内,从而使悬架的运动特性更符合设计要求。     

基于遗传算法的麦弗逊悬架参数优化研究

利用ADAMS/Car模块建立了某车麦弗逊式前悬架系统模型,为优化该悬架结构,运用ADAMS/Insight对悬架参数进行了灵敏度分析,根据分析结果和相关参数的设计要求,运用遗传算法对该悬架系统进行优化。在ADAMS/Car中分别对优化前后的悬架进行双轮同向激振仿真试验,对比前轮定位参数的变化量和变化范围。结果表明,前轮主要定位参数的变化量减小,改善了悬架的运动学特性,达到了优化目的,为汽车悬架的设计提供了依据。     

基于ADMAS/CAR仿真的汽车减振系统的设计

麦弗逊式独立悬架因结构简单等优点作为汽车减振系统被广泛应用于微型车与轿车前悬。通过对汽车减振系统——麦弗逊式独立悬架进行设计,利用UG软件建模并进行测量而获取各硬点数据,并利用ADAMS软件建立1/2车辆模型对汽车悬架进行动态仿真,从而验证设计的正确性,达到优化设计的目的。     

基于ADAMS的麦弗逊式悬架的仿真与优化

在Adams中的Car模块建立麦弗逊式悬架模型,接着进行Parallel Wheel Travel(车轮同向跳动)的仿真分析,分析车轮定位参数随车轮跳动行程的变化规律,确定优化目标。然后在Adams中的Insight模块对悬架的部分硬点坐标进行了优化处理,最后对优化前后的曲线进行了对比,得出结论优化后的硬点坐标改善了汽车悬架的运动学性能。因而,利用ADAMS运动学分析软件,大大缩短了机械动力学的研发周期和成本。     

基于空间解析几何的双横臂独立悬架运动学分析

针对汽车悬架运动学分析方法中存在计算过程复杂、不易编程计算的问题,给出了一种应用空间解析几何理论建立双横臂独立悬架运动学性能参数的数学模型的方法。首先在ADAMS软件中建立了双横臂独立悬架的实体仿真模型,仿真结果表明所建数学模型正确、可靠;然后为便于工程实际应用,以Matlab为设计平台,开发了可视化的双横臂独立悬架运动学分析界面GUI,该界面友好、易于设计人员操作;最后利用该界面输出的曲线评价了双横臂独立悬架的运动学性能。研究结果表明,该方法简便直观、易于实现计算机编程,在一定程度上提升了悬架运动学分析及改进设计的效率。     

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...     

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.     

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。     

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。     

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。     

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.     

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.     

交通荷载作用下桥梁结构参数识别方法

应用动力节点加载法,将作用在桥梁上的交通荷载转化为等效节点荷载,再用两步构造法识别结构物理参数.第1步,用Newmark-β方法变换结构运动方程,并用结构的加速度响应求得变换空间内的位移、速度和加速度响应;第2步,基于最小二乘原理,构造出变换空间内求解结构参数的递推式,进行结构物理参数识别.数值模拟结果表明,在交通荷载作用下,该方法能够快速、准确地进行桥梁结构参数识别.     

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.