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91.
丁渭平 《汽车工程》2005,27(5):583-586
基于车辆系统动、静力学分析及优化设计原理,提出了一种旨在揭示汽车悬架弹性元件最佳刚度分布的工程设计新方法,可确定满足整车平顺性和操纵稳定性协调设计要求的悬架弹性元件的刚度特性,从而为弹性元件的结构优化设计提供了目标依据,并通过一个工程实例验证了所提方法的有效性。  相似文献   
92.
轿车悬架空间五连杆机构尺度综合   总被引:1,自引:0,他引:1  
金洵浩  朱德绵 《汽车工程》2002,24(3):241-244
对轿车悬架五连杆机构进行自由度计算;论述应用位置反解方程进行该机构刚体导引尺度综合的一般方法;指出轮轴构件作圆弧轨迹平动时能使车轮轨迹角不变;阐述进行该机构尺度综合的设计计算方法;由算例得到一组与实际相符的位置与结构参数值,供悬架设计时参考。  相似文献   
93.
Hardware-in-the-loop (HiL) is a testing method in which real-time measurements on physical hardware replace the mathematical model of the particular hardware during simulation. The development of a semi-active suspension prompted the need for such capability. HiL, implemented on a PC with a dSpaceTM board in conjunction with a hydrodynamic actuator, was compared to software simulations of single degree of freedom (DOF) and two DOF systems. HiL was also compared to a physical (ballast-based) two DOF system, comprising the rear suspension of a motorcycle. Comparisons between the HiL and software responses showed its suitability for testing suspension systems, thus providing a viable alternative to ballast-based suspension tests, using available hardware. The research also showed that actuator dynamics, filter types and amounts, and signal reference levels required special consideration.  相似文献   
94.
A few cities in some of the larger developing countries in Latin America and Asia have made increasing use of multi-year concessions or franchises, competitively awarded to private companies, for construction and operation of urban transport infrastructure and for provision of public transport services. In view of the strong prospective growth of developing-country cities with large transport needs, and the rise in the emerging economies of potential new sources of private capital, it is important to see how effective PPP has so far been in this area. The experience is analyzed principally by thorough comparative review of what has actually happened for some of the main users to date: Bogotá, Santiago, São Paulo, Seoul, and several cities in both China and India. Despite delays and mistakes that have been made in development of most of the projects, the overall results, already delivered and in prospect, are very positive and urban public transport is benefiting substantially, with significant side effects on poorer people's access to work and to services, air pollution levels and road accident rates. The widest and most important advantage of the PPP arrangements, as compared with more conventional short-term contracting, is found to be the innovations, technical and managerial, developed, and, in particular, the mutual capacity building of the countries' private and public sectors and their more effective interaction. The experience in the six countries covered suggests that other developing-country cities may be best assisted to develop sound urban transport PPPs more rapidly through provision of help on chosen items among 7 elements that have proved particularly crucial but sometimes weak in the projects reviewed: Civic consultation systems, Land-use/Transport strategic planning, Land/property market management, Monitoring systems, Progressive policies, Economic regulation, and Public institutional framework for PPPs.  相似文献   
95.
制动性能是衡量车辆好坏的一个重要指标,世界上任何一个国家对此都有严格要求。本文着重介绍一款轻型载货车辆在设计验证过程中,车辆空载行驶速度超过40km/h时,在紧急制动情况下后桥出现抖动现象。通过对车辆制动系统、悬架系统全面分析,找到问题所在,最后在不影响车辆性能的前提下,通过适当调整后悬架板簧的刚度达到解决车辆制动抖动。  相似文献   
96.
肖恩源 《公路》2001,(7):67-72,101
按双悬挂索的受力特性,应用悬挂索重力刚度解析双悬挂索结构的经济效果和修建多跨悬索桥的可行性,并以示例予以说明。  相似文献   
97.
98.
A bond graph model of a mountain bike and rider is created to develop baseline predictions for the performance of mountain bikes during large excursion maneuvers such as drops, jumps, crashes and rough terrain riding. The model assumes planar dynamics, a hard-tail (front suspension only) bicycle and a rider fixed to the bicycle. An algorithm is developed to allow tracking of a virtual tire-ground contact point for events that separate the wheels from the ground. This model would be most applicable to novice mountain bikers who maintain a nearly rigid relationship between their body and the bicycle as opposed to experienced riders who are versed in controlling the bicycle independent of the body. Simulations of a steep drop are performed for various initial conditions to qualitatively validate the predictions of the model. Results from this model are to be compared to experimental data and more complex models in later research, particularly models including a separate rider. The overarching goals of the research are to examine and understand the dynamics and control of interactions between a cyclist and mountain bike. Specific goals are to understand the improvement in performance afforded by an experienced rider, to hypothesize human control algorithms that allow riders to perform manoeuvres well and safely, to predict structural bike and body forces from these maneuvers and to quantify performance differences between hard-tail and full suspension bicycles.  相似文献   
99.
两栖空气动力艇悬挂系统设计仿真   总被引:1,自引:1,他引:0  
为了提高两栖空气动力艇在冰雪路面上的通过能力,设计了一种用于两栖空气动力艇的新型独立悬挂系统。在CATIA中建立独立悬挂系统的几何模型,通过CAD/CAE软件的数据接口技术将其导入ADAMS/VIEW环境中进行典型工况条件下的动力学仿真,根据仿真结果对独立悬挂系统进行动力学分析,确定了减震器的阻尼特性以及橡胶衬套的刚度,并验证了该系统中各个构件之间的运动关系。  相似文献   
100.
通过研究发现,发动机悬置系统对车辆的NVH表现影响比较大,文章通过调整整车悬置长度、悬置强度、正时罩盖(又称发动机前罩盖、正时链条盖)强度、悬置螺栓安装点等结构参数,对悬置系统进行仿真计算,提高发动机悬置系统的刚度,优化发动机NVH性能,减轻产品的重量,从而达到最优化设计。  相似文献   
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