基于麦弗逊式独立悬架的平顺性分析

悬架是现代汽车上的重要总成之一,它把车架与车轴弹性地连接起来。它的主要作用是传递作用在车轮和车身之间的一切力和力矩,缓和由不平路面传给车身的冲击载荷、衰减由此引起的振动、减小货物和车辆本身的动载荷,保证乘员的舒适性,以保证汽车的行驶平顺性。     

空气悬架性能分析

以1／4钢板弹簧悬架车辆和空气悬架车辆模型为仿真对象，建立模运动微分方程，模拟C级路面为随机输入，对模型进行了计算机仿真。研究结果表明：空气悬架车辆的车身加速度、悬架动挠度和车轮动载荷都有所降低，其操纵稳定性能和平顺性能明显优于钢板弹簧悬架车辆。     

空气悬架性能分析

以1/4钢板弹簧悬架车辆和空气悬架车辆模型为仿真对象,建立模运动微分方程,模拟C级路面为随机输入,对模型进行了计算机仿真。研究结果表明:空气悬架车辆的车身加速度、悬架动挠度和车轮动载荷都有所降低,其操纵稳定性能和平顺性能明显优于钢板弹簧悬架车辆。     

空气悬架性能分析

以1/4钢板弹簧悬架车辆和空气悬架车辆模型为仿真对象,建立模运动微分方程,模拟C级路面为随机输入,对模型进行了计算机仿真.研究结果表明空气悬架车辆的车身加速度、悬架动挠度和车轮动载荷都有所降低,其操纵稳定性能和平顺性能明显优于钢板弹簧悬架车辆.     

橡胶悬架与钢板弹簧悬架的平顺性对比分析

对某型汽车起重机橡胶悬架和钢板弹簧悬架两种配置进行对比分析,分析两者在结构形式、刚度和阻尼等方面的差异。应用美国军用标准MTL-STD-810F,即人体工程学国防部设计规范标准,对配置橡胶悬架和钢板弹簧悬架两种后悬架的汽车起重机分别进行不同车速、不同等级路面条件下的平顺性随机输入试验测试。试验结果表明,配置钢板弹簧后悬架的车辆,其随机振动平顺性明显优于配置橡胶后悬架的车辆。     

液压电梯起动平顺性的研究

本文在建立液压电梯系统模型的基础上,通过仿真和试验发现摩擦非线性是影响液压电梯起动平顺性的根本原因,提出了有效的改善措施。     

商用车空气悬架轻量化的发展

介绍商用车空气悬架的发展历史、结构和优势,以及国内外空气悬架轻量化的发展现状。对空气悬架中的前支架、导向臂和空气弹簧结构的轻量化进行详细论述：在材料方面,利用复合材料和高强度合金材料所生产的部件替代现有的部件,有效减轻了部件质量;在结构方面,运用拓扑优化方法,对现有的结构进行优化设计,取得了较好的轻量化效果。     

采用油气悬架的汽车起重机平顺性试验分析

本文采用室内台架试验的方法，通过对某型采用油气悬架的汽车起重机按标准路谱进行整车道路模拟试验的方式来研究车辆平顺性性能，克服了实际路面试验不可重复性等困难，并对采用油气悬架系统车辆平顺性进行评价。用这种试验的方法同时获取了许多重要的数据，为研究采用油气悬架车辆的其它性能提供了一种新的途径。     

提高工程车辆平顺性的控制技术研究

工程车辆采用半主动油气悬架可较好地缓和因路面而产生的冲击振动，改善驾驶员的劳动条件。以行驶平顺性及操纵稳定性为控制目标，将LMS自适应滤波算法应用于半主动油气悬架系统的控制。与被动油气悬架系统相比，簧上质量加速度、车轮动载荷、悬架动挠度指标得到明显改善，表明对油气悬架的振动控制收到了较好效果。     

基于联合仿真的半主动悬架车辆平顺性

为减少车辆悬架系统开发周期和成本,利用SIMPACK软件建立了车辆1/4悬架多体动力学模型,基于天棚控制策略设计了半主动悬架控制器,并通过MATLAB / SIMULINK 编写了控制算法对其进行联合仿真.将采用半主动悬架系统得到的仿真结果与采用被动悬架系统得到的仿真结果进行了对比,车身垂直加速度均方根值减少了30.2%.结果表明,基于天棚控制的半主动悬架可以有效衰减车身的振动,改善车辆的行驶平顺性,从而为车辆动力学系统的仿真分析提供了一种有效方法.     

基于联合仿真的主动油气悬架工程车平顺性研究

以W4-60C型轮式挖掘机为研究对象,利用ADAMS／Car软件建立了机械模型,在Marlab／Simulink环境中设计了PID与自适应模糊PID控制系统,将设计的主动控制系统与建立的机械模型进行车辆平顺性的联合仿真,通过实验发现主动控制方法能实现车辆平顺性的提升,并且自适应模糊PID控制效果更好,展现了联合仿真技术的互补性和主动油气悬架的优越性,为车辆的进一步开发与设计提供依据。     

Effects of bridge motion and crosswind on ride comfort of road vehicles

Ride comfort of road vehicles running on the ground has been extensively investigated as one of the main criteria in the design of road vehicles. The information on the ride comfort of road vehicles running on a long span cable-supported bridge under crosswind is, however, very limited. This paper presents an evaluation of ride comfort of road vehicles running on a long span cable-stayed bridge under crosswind. The ride comfort criteria for road vehicles are briefly reviewed first. The principle of mathematical modeling and the equation of motion of a coupled road vehicle–bridge system under crosswind are then introduced. The framework proposed is finally applied to a group of high-sided road vehicles running on a real cable-stayed bridge under crosswind as a case study. Ride comfort of the high-sided road vehicle under various conditions of road roughness, vehicle speed, and crosswind speed is investigated for the vehicle running on either the ground or the cable-stayed bridge with and without crosswind. The results show that the crosswind influences the ride comfort of the vehicle in the lateral direction while the bridge motion affects the ride comfort of the vehicle in the vertical direction.     

侧风与桥梁振动对车辆行驶舒适性影响研究

风-汽车-桥梁系统空间耦合振动是风-桥、风-汽车及汽车-桥梁系统相互作用三方面协调工作的结果,其振动特性取决于自然风特性、车辆动力特性、桥梁振动特性、车辆和桥梁气动特性相互影响等多种因素,将风、汽车、桥梁三者作为一个相互作用的系统,提出一个较为完善的风-汽车-桥梁系统空间耦合振动分析模型,编制相应的分析模块WVB(wind-Vehicle-Bridge system analysis),并嵌入到自行研发的桥梁结构动力分析软件BDANS(Bridge Dynamic ANalysis System).建立车辆驾驶员位置处驾驶舒适性评价方法.研究侧风与桥梁振动对车辆驾驶 舒适性的作用,并探讨路面粗糙度、平均风速和车速对风环境下行驶在大跨度斜拉桥上车辆驾驶舒适性的影响.研究结果表明:侧风对车辆的竖向驾驶舒适性影响不大而主要影响车辆的侧向驾驶舒适性;桥梁振动对车辆竖向驾驶舒适度影响显著并明显改变其频谱特性.     

A hierarchical framework for improving ride comfort of autonomous vehicles via deep reinforcement learning with external knowledge

Ride comfort plays an important role in determining the public acceptance of autonomous vehicles (AVs). Many factors, such as road profile, driving speed, and suspension system, influence the ride comfort of AVs. This study proposes a hierarchical framework for improving ride comfort by integrating speed planning and suspension control in a vehicle-to-everything environment. Based on safe, comfortable, and efficient speed planning via dynamic programming, a deep reinforcement learning-based suspension control is proposed to adapt to the changing pavement conditions. Specifically, a deep deterministic policy gradient with external knowledge (EK-DDPG) algorithm is designed for the efficient self-adaptation of suspension control strategies. The external knowledge of action selection and value estimation from other AVs are combined into the loss functions of the DDPG algorithm. In numerical experiments, real-world pavements detected in 11 districts of Shanghai, China, are applied to verify the proposed method. Experimental results demonstrate that the EK-DDPG-based suspension control improves ride comfort on untrained rough pavements by 27.95% and 3.32%, compared to a model predictive control (MPC) baseline and a DDPG baseline, respectively. Meanwhile, the EK-DDPG-based suspension control improves computational efficiency by 22.97%, compared to the MPC baseline, and performs at the same level as the DDPD baseline. This study provides a generalized and computationally efficient approach for improving the ride comfort of AVs.     

甘肃省体育馆悬吊楼盖人致振动舒适度现场测试研究

对于悬吊楼盖,其悬吊端竖向刚度较弱,人群荷载激励下易发生较大振动.以甘肃省体育馆13.500m标高悬吊楼盖为研究对象,在主体结构完工后,首先,测试了楼盖在环境脉动激励作用下的振动模态;其次,参照楼盖的振动模态实测了楼盖在不同激励下包括单人行走、多人行走、多人跳跃、多人跑步、自由运动等工况下的加速度反应;最后根据楼盖的建筑使用功能,以峰值加速度为指标评估该悬吊楼盖的振动舒适度.结果 表明,悬吊楼盖在人行荷载作用下存在较为显著的振动响应和一定程度的振动舒适度问题,人致激励的类型和路线对楼盖的振动舒适度有显著的影响.     

基于实测响应的大跨度人行悬索桥舒适度评价

本文从实测的振动频率、振幅和振动加速度等方面动力响应对一大跨度人行悬索桥进行了综合的舒适度评价。环境振动试验和人群激励试验实测结果表明在人群荷载作用下,该桥振动感觉指标满足人行舒适度要求。     

Thermal comfort assessment in semi-outdoor environments: Application to comfort study in stadia

The present study addresses thermal comfort assessment of outdoor and semi-outdoor environments. Two stadium case studies are used to demonstrate the potentiality of the approach that combines wind tunnel data and the calculation of human heat balance due to particular climatic environments. The thermal index PET (physiological equivalent temperature) is used to evaluate the thermal comfort in such complex environments. The specificities of stadium semi-outdoor spaces are summarised and the necessary assumptions made to apply the computation procedure are described. The approach includes assumptions on the thermo-physical phenomena as well as geometric computations. This work benefited from the development of an interactive design tool of built environments (outdoor urban surroundings): EVE (enriched virtual environments). It is a virtual reality platform developed at CSTB to help designers, architects and urban planners to evaluate the various options in competition regarding acoustic, visual, thermal and wind comfort of pedestrian in a particular urban environment.     

铁路站房高架候车层气流组织及热舒适性研究

针对新广州站和深圳北站高架候车层的空调设计特点,应用CFD软件对空调设计原始方案的夏季气流组织分布情况进行了模拟分析,并提出了改进建议,分析了改进方案的温度场、速度场及热舒适度分布情况。     

电梯舒适感之浅析

指出随着电梯使用量的增多,其舒适性也成为使用者及业内关注的焦点。根据多年的工作经验,对影响电梯舒适感的多种因素进行了分析,从影响舒适感的振动与噪声两方面进行了论述,以解决运行中的舒适感问题。     

Air movement acceptability limits and thermal comfort in Brazil's hot humid climate zone

In hot humid climates, natural ventilation is an essential passive strategy in order to maintain thermal comfort inside buildings and it can be also used as an energy-conserving design strategy to reduce building cooling loads by removing heat stored in the buildings thermal mass. In this context, many previous studies have focused on thermal comfort and air velocity ranges. However, whether this air movement is desirable or not remains an open area. This paper aims to identify air movement acceptability levels inside naturally ventilated buildings in Brazil. Minimal air velocity values corresponding to 80% and 90% (V80 and V90) air movement acceptability inside these buildings. Field experiments were performed during hot and cool seasons when 2075 questionnaires were filled for the subjects while simultaneous microclimatic observations were made with laboratory precision. Main results indicated that the minimal air velocity required were at least 0.4 m/s for 26 °C reaching 0.9 m/s for operative temperatures up to 30 °C. Subjects are not only preferring more air speed but also demanding air velocities closer or higher than 0.8 m/s ASHRAE limit. This dispels the notion of draft in hot humid climates and reinforce the broader theory of alliesthesia and the physiological role of pleasure due to air movement increment.