摩托车后视镜新标准应对措施探讨

摩托车后视镜作为车辆的安全装置之一,对骑乘者、行人及车辆安全起着至关重要的保护作用。随着GB 17352—2010《摩托车和轻便摩托车后视镜的性能和安装要求》标准的颁布与实施,诸多设计、使用上的安全问题需引起高度重视。     

基于RBF网络的后桥齿轮残余寿命预测研究

为有效预测汽车后桥齿轮的残余寿命,针对后桥的非线性特性,提出了一种递归预处理与RBF网络相结合的齿轮残余寿命预测方法,并验证了该方法的可行性.利用该方法进行了汽车后桥齿轮残余寿命预测,结果表明,该方法对齿轮残余寿命的预测结果与齿轮疲劳试验结果吻合,预测精度高.     

回复反射技术在汽车上的应用和标准研究

回复反射技术以其独特的回复反射性能广泛应用于交通领域。文章以回复反射器、三角警告牌、车身反光标识和尾部标志板等回复反射产品为例,分析了回复反射技术在汽车领域的应用现状,重点探讨了回复反射技术中的车身反光标识技术。在对我国车身反光标识标准中所规定的回复反射性能和粘贴技术规范等方面与欧美国家标准的异同分析比较的基础上,提出了中国的应对措施。回复反射产品增加了车辆的识别性,提高了道路行车安全性能。     

Nonlinear PI front and rear steering control in four wheel steering vehicles

Vehicle steering dynamics show resonances, which depend on the longitudinal speed, unstable equilibrium points and limited stability regions depending on the constant steering wheel angle, longitudinal speed and car parameters.

The main contribution of this paper is to show that a combined decentralized proportional active front steering control and proportional-integral active rear steering control from the yaw rate tracking error can assign the eigenvalues of the linearised single track steering dynamics, without lateral speed measurements, using a standard single track car model with nonlinear tire characteristics and a non-linear first-order reference model for the yaw rate dynamics driven by the driver steering wheel input. By choosing a suitable nonlinear reference model it is shown that the responses to driver step inputs tend to zero (or reduced) lateral speed for any value of longitudinal speed: in this case the resulting controlled vehicle static gain from driver input to yaw rate differs from the uncontrolled one at higher speed. The closed loop system shows the advantages of both active front and rear steering control: higher controllability, enlarged bandwidth for the yaw rate dynamics, suppressed resonances, new stable cornering manoeuvres, enlarged stability regions, reduced lateral speed and improved manoeuvrability; in addition comfort is improved since the phase lag between lateral acceleration and yaw rate is reduced.

For the designed control law a robustness analysis is presented with respect to system failures, driver step inputs and critical car parameters such as mass, moment of inertia and front and rear cornering stiffness coefficients. Several simulations are carried out on a higher order experimentally validated nonlinear dynamical model to confirm the analysis and to explore the robustness with respect to unmodelled dynamics.     

车门内板后部冲压工艺优化(续1)

为优化车门内板后部的冲压工艺,文章采用AutoForm软件对该部件进行了CAE成型性分析,并根据修边工艺性和冲孔工艺性判定,制定了工艺方案。结果表明,对于采用工艺手段无法解决的破裂问题,应提出设计变更;对于车门内板后部,需要利用拉延筋的力及补充面造型来控制起皱。为避免出现简单工艺问题,设计人员需了解冲压工艺,而且工艺性问题优先用工艺手段解决,若需要增加成本,则优先更改产品设计。     

汽车前后轴台架疲劳试验与海南汽车试验场的疲劳寿命当量关系

以某轻型汽车后桥壳为例，运用工程疲劳寿命估算与道路模型疲劳试验相结合的方法，给出了该后桥壳基于海南汽车试验场可靠性试验的道路行驶载荷条件下所得到的疲劳寿命概率分布。     

轻型车后桥二维载荷谱及其疲劳寿命预测

以雨流法得到的载荷谱为基础，建立了后桥的二维载荷谱，并编制了二维载荷谱的计算机程序，分别利用一维和二维载荷谱对ＥＱ１０３０Ｔ型轻型车后桥进行了疲劳寿命预测。     

Nonlinear PI front and rear steering control in four wheel steering vehicles

Vehicle steering dynamics show resonances, which depend on the longitudinal speed, unstable equilibrium points and limited stability regions depending on the constant steering wheel angle, longitudinal speed and car parameters.

The main contribution of this paper is to show that a combined decentralized proportional active front steering control and proportional-integral active rear steering control from the yaw rate tracking error can assign the eigenvalues of the linearised single track steering dynamics, without lateral speed measurements, using a standard single track car model with nonlinear tire characteristics and a non-linear first-order reference model for the yaw rate dynamics driven by the driver steering wheel input. By choosing a suitable nonlinear reference model it is shown that the responses to driver step inputs tend to zero (or reduced) lateral speed for any value of longitudinal speed: in this case the resulting controlled vehicle static gain from driver input to yaw rate differs from the uncontrolled one at higher speed. The closed loop system shows the advantages of both active front and rear steering control: higher controllability, enlarged bandwidth for the yaw rate dynamics, suppressed resonances, new stable cornering manoeuvres, enlarged stability regions, reduced lateral speed and improved manoeuvrability; in addition comfort is improved since the phase lag between lateral acceleration and yaw rate is reduced.

For the designed control law a robustness analysis is presented with respect to system failures, driver step inputs and critical car parameters such as mass, moment of inertia and front and rear cornering stiffness coefficients. Several simulations are carried out on a higher order experimentally validated nonlinear dynamical model to confirm the analysis and to explore the robustness with respect to unmodelled dynamics.     

座椅设计参数对低速尾撞中乘员颈部伤害影响的仿真研究

在MADYMO环境下建立包括座椅、座椅安全带、BIORIDⅡ假人的尾撞仿真模型,应用MADYMO及AUTODOE对座椅设计参数及座椅平动吸能机制对低速尾撞中乘员颈部损伤指标的影响进行了研究。模拟结果表明,座椅靠背铰旋转刚度、椅背屈服力矩、椅背接触刚度等参数对乘员头颈部响应的影响显著,通过适当的座椅参数设计可以达到降低尾撞中乘员损伤几率的目的。同时,座椅整体平动吸能对座椅尾撞安全性能的提高也在模拟中得到了验证。     

后桥双轮驱动摊铺机附着性能分析

以ＬＴＹ８型摊铺机为例，介绍了一种典型的摊铺机后桥双轮驱动方式，并分析了其良好的附着性能及避免产生寄生功率的问题。