柔性轮胎及摩擦力对永磁悬浮车辆动力性能的影响

针对永磁悬浮车辆,考虑永磁悬浮力、横向力、柔性轮胎及摩擦力特性对整车的影响,通过A级路面不平顺谱建立了车辆-轮胎-轨道耦合动力学模型,利用仿真软件分析了几种不同特性的轮胎对车辆振动的影响。结果表明:永磁悬浮车辆整车的振动是一个复杂的运动,柔性轮胎及摩擦力能有效减小振动,轮胎的弹性模量对垂直浮沉振动影响小,对横向偏移振动有一定的影响。     

直接式胎压监测系统设计简述

本文针对满足国标GB 26149—2017的直接式胎压监测系统,对工作原理、主要功能、技术实现方案、标定测试等进行了全方位的介绍。     

Tire–road friction coefficient estimation based on the resonance frequency of in-wheel motor drive system

In this paper, a resonance frequency-based tire–road friction coefficient (TRFC) estimation method is proposed by considering the dynamics performance of the in-wheel motor drive system under small slip ratio conditions. A frequency response function (FRF) is deduced for the drive system that is composed of a dynamic tire model and a simplified motor model. A linear relationship between the squared system resonance frequency and the TFRC is described with the FRF. Furthermore, the resonance frequency is identified by the Auto-Regressive eXogenous model using the information of the motor torque and the wheel speed, and the TRFC is estimated thereafter by a recursive least squares filter with the identified resonance frequency. Finally, the effectiveness of the proposed approach is demonstrated through simulations and experimental tests on different road surfaces.     

预制箱梁钢筋骨架和内模整体绑扎吊装施工技术

内模及预制箱梁全部钢筋骨架的整体一次安装具有多方面的优越性。介绍箱梁钢筋骨架和内模整体绑扎吊装技术的特点,内模工装、专用钢筋吊架和专用绑扎胎具等设备工装的设计及其关键配套技术,内模及整体钢筋骨架安装工序,并对施工中常见的问题:如吊装时不能顺利起吊、钢筋骨架变形、钢筋吊架侧弯等进行了研究与处理。有助于提高钢筋骨架绑扎的绑扎质量和速度。     

深大地铁车站基坑机械化组合配套快速开挖技术

南宁地铁1号线火车站站点超宽超大、地质及水文条件复杂、周边临近建筑物、施工环境复杂,基坑开挖难度大。为确保深大基坑的快速开挖和安全施工,提出了电动轮胎式起重机与常规履带式挖掘机组合配套开挖技术,即采用多种型号常规履带式挖掘机坑内配合,电动轮胎式起重机地面提升的施工方法。现场实践表明:(1)电动轮胎式起重机首次引入到地铁车站基坑开挖施工,与常规挖机配套施工高效合理,施工组织方便灵活,施工进度提高了1.5倍以上;(2)电动轮胎式起重机能定点开挖、自动行走、取土深度大、作业半径大、机身占地面积小、节能环保;(3)采用该组合配套机械开挖施工,较常规设备机械费节约80万元,动力费节约12万元,取得了较好经济效益,为复杂环境下宽大基坑机械化施工积累了宝贵经验。     

钢质旋转双耳线夹松动原因分析

旋转双耳线夹是接触网上的重要受力零件,若出现松脱会导致接触网发生断线事故。从试验和理论2个方面论述钢质旋转双耳线夹发生松动的原因并提出改进建议。     

Robust state feedback stabilization of articulated steer vehicles

In this work, a full-state feedback controller is designed to prevent the oscillatory instability or snaking behaviour of an articulated steer vehicle. To design the controller, first, a linearized model of the vehicle is developed and analyzed to identify the most important uncertain tire parameters with regard to the snaking mode. By using this linearized model, the equations of motion are represented in the form of a polytopic system, which depends affinely on the most important uncertain tire parameters. Then, by solving some linear matrix inequalities, both the Lyapunov and state feedback matrices for the robust stabilization of the vehicle are found. The performance of the resulting controller is evaluated by conducting several simulations based on the linearized model. To verify the results from the linearized model analysis, some simulations are also done by a virtual prototype of the vehicle in ADAMS. The results based on the linearized model are reasonably consistent with those from the simulations in ADAMS. They show that the controller can effectively stabilize the vehicle during the snaking mode in different driving conditions.     

内燃机车轮箍加装扣环方案改进

对带轮箍内燃机车的不退轮箍加装扣环的可行性、实施过程、实施结果和经济效益进行了全面分析总结 ,说明了对带轮箍内燃机车的不退轮箍加装扣环符合铁道部颁布的技术标准 ,方案是可行的。     

轮胎泵气噪声有限元仿真分析

轮胎花纹槽泵气噪声是轮胎噪声的主要部分之一。在假设轮胎胎面结构与空气完全耦合的条件下建立轮胎横向花纹槽噪声的有限元模型,在施加与速度相关的强制位移条件下对空气中花纹槽泵气噪声进行仿真仿真,验证轮胎花纹槽泵气噪声的机理,同时通过线性迭加轮胎周向单个横向花纹槽的方法,给出轮胎花纹槽整体噪声的频域曲线。     

正面吊轮胎选型和使用管理

影响正面吊轮胎使用寿命的因素主要有气压不正常、负荷超标、花纹形式差、异物刺穿胎、正面吊结构不合理等 ,通过合理选型和改进轮胎管理、使用和保养方法 ,可达到降低轮胎消耗的目的