汽车行驶平顺性评价方法研究及仿真分析

汽车平顺性是汽车NVH性能的评价指标之一。系统介绍了汽车行驶平顺性的客观评价方法,并结合某车型搭建整车行驶平顺性虚拟样机,进行了仿真分析评价。该方法可用于指导汽车行驶平顺性的改善以及悬架参数的优化。     

货车平顺性预测与优化

本文介绍了货车15个自由度振动模拟模型,以及平顺性预测与优化的方法。利用ARPO软件对某货车的平顺性进行了模拟分析,计算值与道路试验值比较吻合。ARPO软件可用于分析汽车结构参数对平顺性的影响,预测和优化汽车的平顺性。     

悬架偏频对制动性能影响分析

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。     

汽车平顺性计算程序设计

文章基于理论力学中的力学理论,建立了以悬架、轮胎为主体的分析平顺性的半车动力学模型。将此动力学模型转换成为易于求解分析的传递函数和状态空间形式的数学模型,并建立一定的道路模型,得到接近真实状态的汽车平顺性响应。在GUI界面下利用Matlab中的相关函数建立所求得的数学模型,实现对平顺性各响应相关量的求解。结果表明:本次程序设计方案是合理的、可行的。     

Increasing urban tram system efficiency,with battery storage and electric vehicle charging

This paper examines the possible placement of Energy Storage Systems (ESS) on an urban tram system for the purpose of exploring potential increases in operating efficiency through the examination of different locations for battery energy storage. Further, the paper suggests the utilisation of Electric Vehicle (EV) batteries at existing Park and Ride (P&R) sites as a means of achieving additional energy storage at these locations. The study achieves this through MATLAB modelling utilising captured GPS data and publically available information. This study examines the scenario of uni-directional substations with no interconnection between the overhead catenary for both directions of travel, and discusses the trade-offs between ESS size and required current limits.The results show the savings in both energy and basic CO₂ emissions alongside the discussion of Return on Investment (RoI) that can be achieved through the potential installation of ESS at identified ideal locations along the tram network. Moreover, this may be extended to the use of EVs as stationary ESS sited at the existing P&R facilities. Further, the model may also be used to inform future infrastructure upgrades and potential improvements to air quality within urban environments.     

某中型载货车驾驶室异常共振的试验研究

针对某中型载货车在35km/h~40km/h车速附近出现的驾驶室异常共振问题,进行了道路试验,采集驾驶室内与驾驶室悬置周边位置处的振动加速度信号。通过驾驶员总加权加速度均方根值对载货车的乘坐舒适性进行了客观评价,结果表明驾驶室振动异常,乘坐舒适性能很差;通过悬架、驾驶室悬置传递函数的计算与分析,发现驾驶室后左悬置对车桥传递至驾驶室的低频振动起到极大的放大作用,是驾驶室内产生异常共振的主要原因。更换驾驶室后左悬置后,该车速段内的异常共振问题已消除。     

Geometric matching and spatial pricing in ride-sourcing markets

This paper develops a model to investigate the effects of spatial pricing on ride-sourcing markets. The model is built upon a discrete time geometric matching framework that matches customers with drivers nearby. We demonstrate that a customer may be matched to a distant vehicle when demand surges, yielding an inefficient supply state. We further investigate market equilibrium under spatial pricing assuming a revenue maximizing platform, and find that the platform may resort to relatively higher price to avoid the inefficient supply state if spatial price differentiation is not allowed. Although spatial pricing facilitates market clearing, the platform may still set price more than the efficient level, which compromises the public interest. We then propose a commission rate cap regulation that reaps the flexibility of spatial pricing and can achieve the second best under some homogeneity assumptions.     

精密设备半挂运输车悬架匹配设计及运输平顺性仿真

为解决精密设备在半挂车运输中的振动问题,采用了一种半挂车鹅颈柔性牵引装置。在ADAMS中建立了整车多刚体动力学仿真模型,并对整车的悬架系统进行了匹配计算,通过随机路面输入的平顺性仿真分析,取得较好的结果,减轻了车辆对精密设备在运输过程中的振动破坏。     

驾驶室悬置对整车平顺性影响的试验研究

某车型分别装配固定式前悬置、液压式前悬置驾驶室,在沥青路面以50km/h、60km/h、70km/h的速度,沙石路面以20km/h的速度进行平顺性试验,使用FlexPro8.0软件对试验数据进行分析处理,得出两种驾驶室悬置对整车平顺性的影响。     

Comfort enhancement by an active vibration reduction system for a flexible railway car body

In order to improve the ride comfort of lightweight railway vehicles, an active vibration reduction system using piezo-stack actuators is proposed and studied in simulations. The system consists of actuators and sensors mounted on the vehicle car body. Via a feedback control loop, the output signals of the sensors which are measuring the flexible deformation of the car body generate a bending moment, which is directly applied to the car body by the actuators. This bending moment reduces the structural vibration of the vehicle car body. Simulations have shown that a significant reduction in the vibration level is achieved.