转向轮侧滑的危害、检测及调整

转向轮侧滑的危害转向轮定位参数(主销后倾角、主销内倾角、车轮外倾角和车轮前束等)配合不当引起转向轮侧滑,会破坏车轮的附着能力,使汽车丧失定向行驶能力,导致轮胎异常磨损,并可能引发交通事故。其危害主要有:①汽车行驶时发生侧滑,会使汽车的行驶阻力增加,对汽车的动力性、     

汽车转向轮侧滑量不合格的原因分析

<正>转向轮侧滑量是车辆性能检测中的一个重要项目,其数值大小反映了转向轮定位参数的准确程度,通过对其有效分析,有利于快速排查出故障部位,进而采取针对性措施消除隐患,保证车辆行驶的操纵性和稳定性正常有效。本文在分析了转向轮侧滑量异常的表现形式和影响因素的基础上,提出了相关预防及消除措施。1转向轮侧滑量的形成机理为了保证车辆在行驶过程中有灵敏的操纵性和可靠     

遗传算法在车轮定位参数测量中的应用

结合在侧滑试验台上做试验确定的车辆前进或后退时的侧滑量与车轮外倾角及前束值间的映射关系，介绍遗传算法在车轮定位参数测量中的应用。计算结果表明，该方法不仅可以快速测量出两车轮定位参数，并可有效地指导车辆检修人员进行车轮定位参数的调整。     

双板联动侧滑仪对独立悬挂车辆转向轮侧滑量检测结果的分析

汽车转向轮具有的保持自动返回直线行驶的能力称为转向轮的稳定效应。它是通过转向轮的定位角来实现的。研究表明,转向轮定位参数中车轮前束与外倾角对车轮侧滑的影响比较大。当车轮前束值与外倾角匹配不当时,车轮就可能在直线行驶过程中不做纯滚动,产生侧向滑移现象。当这种滑     

前轮定位参数优化设计和试验的研究

以减少侧滑量为目标推导出前轮外倾角与前束值合理匹配关系的计算公式。基于转向回正性能和轻便性,并计及残留横摆角速度和前轮定位诸参数之间的关系,建立一种前轮定位参数优化设计方法。以某轻型货车为例,对其前轮定位参数值进行优化,通过相关试验验证了所选定位参数的正确性和合理性。     

独立悬架车辆转向轮侧滑及检测设备适应性分析

从侧向力的角度分析了转向桥为独立悬架的车辆转向轮侧滑的产生机理,对目前常用的两种独立悬架车辆转向轮侧滑试验台的适应性进行了研究分析,提出了改造建议。     

基于RBF神经网络的车轮定位参数识别

结合在侧滑试验台上做试验确定的车辆侧滑量与车轮外倾角及前束值间的映射关系，提出利用RBF神经网络对车轮定位参数优化识别的方法，并编制相应的程序。试验结果表明该方法能快速识别出车轮定位参数，并能指导检修人员进行车轮外倾角和车轮前束值调整。     

汽车转向机构设计参数与前束变化规律关系的研究

通过建立数学计算模型,本文研究并确定了前置转向梯形独立悬挂转向系统的零部件设计参数以及转向机构的布置形式等对汽车加载时转向轮前束变化规律的影响因素,建立了前束角与各影响因素的计算公式,定量地解决了实现汽车加载时转向轮前束变化的理论理想特性的方式和方法,可以对汽车前轮定位参数布置设计合理性以及正确性进行定量判定。本文以HELUX底盘的转向机构为算例对计算模型和计算公式进行了计算和验证。     

横向侧滑量检验作业指导书——用双板联动式侧滑台检验

<正>转向轮横向侧滑量是机动车辆安全技术检验的重要指标。本作业指导书根据有关标准及检验机构实际检验流程制定。本作业指导书着重阐述了横向侧滑量检验程序,侧滑台零位误差检查、校准方法及使用维护注意事项,具有实际指导意义。     

汽车前轮侧滑仪综述

汽车侧滑仪用于检测汽车转向轮定位值是否正常，是汽车安全性能检测站的必备设备之一，其结构类型主要有五种。文中对这五种侧滑仪的性能进行了分析。     

基于人-车-路虚拟试验的道路线形安全性评价

为了避免由于线形设计不良造成日后事故多发路段的产生,提出了基于人-车-路虚拟试验的道路线形设计安全性评价方法。首先基于对公路线形导致交通事故的分析,选取并构造了轨道跟踪误差、转向任务间隔、方向盘峰值转速、侧向加速度、垂直荷载和路段通行极限车速为道路线形安全性评价指标;采用EICAD和多体动力学软件ADAMS/Car实现了道路设计方案的三维建模,然后与车辆模型、驾驶员模型构成仿真环境完成了对安徽至浙江某高速公路线形设计方案的安全性评价;多数评价指标显示该设计路线安全性较好,但路段通行极限车速显示该路段前段(里程0~2.47 km)行车速度分布较分散,容易诱发超速行驶,为潜在的事故多发路段。     

汽车操纵稳定性的中间位置转向试验

操纵稳定性中间位置转向试验最初是由美国德尔福公司制定的，是汽车在高速行驶条件下操纵性和稳定性的重要评价方法。通过试验的原始数据可以绘制出转向盘转角与侧向加速度、转向盘力矩与侧向加速度、转向盘力矩与转向盘转角等多条特性曲线，以作为不同的评价指标。以CAll41载货汽车作为实例分析，发现该车转向干摩擦偏大，转向刚度偏低，高速行驶时的非线性路感不够理想。     

A lateral driver model for vehicle–driver closed-loop simulation at the limits of handling

This paper presents a lateral driver model for vehicle–driver closed-loop simulation at the limits of handling. An appropriate driver model can be used to evaluate the performance of vehicle chassis control systems via computer simulations before vehicle tests which incurs expenses especially at the limits of handling. The driver model consists of two parts. The first part is an upper-level controller employing force-based approach to reduce the number of unknown vehicle parameters. The feedforward part of the upper controller has been designed by using the centre of percussion. The feedback part aims to minimise ‘tangential error’, defined as the sum of body slip angle and yaw error, to match vehicle direction and road heading angle. The part is designed to regenerate an appropriate skid motion similar to that of a professional driver at the limits. The second part is a lower-level controller which converts the desired front lateral force to steering wheel angle. The lower-level controller also consists of feedforward and feedback parts. A two-degree-of-freedom bicycle model-based feedforward part provides nominal steering wheel angle, and the feedback part aims to eliminate unmodelled error. The performance of the lateral driver model has been investigated via computer simulations. It has been shown that the steering behaviours of the proposed driver model are quite close to those of a professional driver at the limits. Compared with the previously developed lateral driver models, the proposed lateral driver model shows good tracking performance at the limits of handling.     

转向加速工况下汽车驱动防滑控制系统滑转率算法研究

汽车低速转弯加速时,用后轮轮速作为参考车速计算驱动轮滑转率会造成计算偏差,引起驱动防滑控制系统误干预,为此提出了驱动轮滑转率计算的修正算法.该修正算法不需要增加前轮转角传感器,而是采用两非驱动轮轮速估计车身横摆角速度和汽车前轮转角,进而计算出前轮参考轮速,并将前轮参考轮速代替车速对转弯工况的驱动轮滑转率计算进行修正.试验结果表明,该修正算法消除了滑转率计算误差,可防止汽车在高附着路面上转弯加速时驱动防滑控制系统的误干预.     

Vehicle steering returnability with maximum steering wheel angle at low speeds

In this paper, an analytical model with suitable vehicle parameters, together with a multi-body model is proposed to predict steering returnability in low-speed cornering with what is expected to be adequate precision as the steering wheel moves from lock to lock. This model shows how the steering response can be interpreted in terms of vertical force, lateral force with aligning moment, and longitudinal force. The simulation results show that vertical steering rack forces increase in the restoring direction according to steering rack displacement for both the inner and outer wheels. As lateral forces due to side-slip angle are directed toward the medial plane of the vehicle in both wheels, the outer wheel pushes the steering wheel in the returning direction while the inner wheel does not. In order to improve steering returnability, it is possible to increase the total steering rack force in both road wheels through adjustments to the kingpin axis and steering angle. This approach is useful for setting up a proper suspension geometry during conceptual chassis design.     

基于小波控制的电动汽车稳定性研究（双语出版）

针对前轮独立驱动电动汽车,研究一种基于小波控制器的驱动稳定性控制系统。为提高车辆对开路面的行驶稳定性,根据驱动轮等转矩分配控制策略,提出基于神经网络PID的驱动轮滑移率相近为目标控制策略。针对矢量控制中的电流控制,提出基于离散小波变换的电流控制器。通过CarSim/Simulink建立前轮独立驱动电动汽车联合仿真平台,进行不同工况整车性能仿真与分析,并基于A&D5435快速原型开发平台进行实车试验。仿真与试验结果表明：基于小波控制器的驱动控制系统不仅提高了车辆对开路面行驶的稳定性,而且具有更平滑、更快速的转矩响应;对开路面工况下,提出的控制策略左侧、右侧驱动轮速度仿真结果与试验结果最大偏差分别为3.43%和3.56%;等转矩分配控制策略下,左侧、右侧驱动轮速度仿真结果与试验结果最大偏差分别为3.86%和3.25%,表明了试验与仿真的一致性;对开路面仿真工况下,相比于驱动轮等转矩分配控制策略,基于神经网络PID的驱动轮滑移率相近为目标控制策略的车辆峰值质心侧偏角降低了79.57%,侧向跑偏距离降低了73.39%。     

Integrated control of brake pressure and rear-wheel steering to improve lateral stability with fuzzy logic

This study introduces an integrated dynamic control with steering (IDCS) system to improve vehicle handling and stability under severe driving conditions. It integrates an active rear-wheel steering control system and a direct yawmoment control system with fuzzy logic. Direct yaw-moment control is achieved by modifying the optimal slip of the front outer wheel. An 8-degree-of-freedom vehicle model was used to evaluate the proposed IDCS for various road conditions and driving inputs. The results show that the yaw rate tracked the reference yaw rate and that the body slip angle was reduced when the IDCS was employed, thereby increasing the controllability and stability of the vehicle on slippery roads. The IDCS system reduced the deviation from the center line for a vehicle running on a split m road.     

Integrated chassis control for a three-axle electric bus with distributed driving motors and active rear steering system

This paper describes an integrated chassis control framework for a novel three-axle electric bus with active rear steering (ARS) axle and four motors at the middle and rear wheels. The proposed integrated framework consists of four parts: (1) an active speed limiting controller is designed for anti-body slip control and rollover prevention; (2) an ARS controller is designed for coordinating the tyre wear between the driving wheels; (3) an inter-axle torque distribution controller is designed for optimal torque distribution between the axles, considering anti-wheel slip and battery power limitations and (4) a data acquisition and estimation module for collecting the measured and estimated vehicle states. To verify the performances, a simulation platform is established in Trucksim software combined with Simulink. Three test cases are particularly designed to show the performances. The proposed algorithm is compared with a simple even control algorithm. The test results show satisfactory lateral stability and rollover prevention performances under severe steering conditions. The desired tyre wear coordinating performance is also realised, and the wheel slip ratios are restricted within stable region during intensive driving and emergency braking with complicated road conditions.     

转矩式限滑差速器对后轮驱动汽车操纵稳定性影响的研究

采用7自由度车辆动力学模型,对装用JA1020LSD型转矩式限滑差速器的后轮驱动汽车进行了操纵稳定性研究。通过仿真分析和道路试验研究表明:装用限滑差速器后增加了后轮驱动车辆的不足转向趋势,即改善了操纵稳定性,但转向力矩略有增加。     

低附着弯道路面车辆制动力控制策略研究

分析了车辆ABS系统在弯道制动时存在的横向稳定性问题,提出了一种低附着弯道路面车辆制动力控制策略.它综合考虑车轮防抱死与车辆发生侧滑时所能承受的最大侧向力,根据两者所允许的最大制动力中较小值确定施加于车辆的制动力.所进行的数值仿真结果表明该控制方法能提高车辆在低附着弯道路面上的横向稳定性.