中型越野车转向问题浅析

在提高中型越野车机动性研究中,分析了在低等级路面高机动性行驶时出现的方向盘打手驾驶体验差问题的主要原因,提出了配装电动辅助转向系统(EAS)的解决方案。某中型越野车分别配装液压助力转向系统(HPS)和EAS进行了对比试验研究。试验项目包括试验场低等级路面(大小圆凸起路、卵石路、搓板路和石块路)高机动性行驶和转向回正,得到了配装2种转向系统的方向盘手力矩对比数据。结果表明,中型越野车配装EAS能够较好解决前述问题。     

Deflection test and transmission error measurement to identify hypoid gear whine noise

T-Hypoid gears are commonly used in rear-drive and 4WD (4 Wheel Drive) vehicle axles. Investigating their sensitivity to deflections is one of the most important aspects of their design and optimization procedures. Therefore, a deflection test was performed in this study in the actual gear mounting using completely processed gear. This test covered the full operating range of gear loads from “no load” to “peak load”. Under peak load, the contact pattern extended to the tooth boundaries without showing a concentration of the contact pattern at any point on the tooth surface. The transmission error was tested under an axle assembly triaxial-real-car-load condition.     

独立悬架汽车转向系统刚度测量

汽车转向系统刚度是影响汽车操纵稳定性的重要因素之一，本文介绍了一种实用的测量独立悬架汽车转向系统刚度的试验方法，分析了汽车转向系统的受力状况，推导了转向系统中各环节刚度的计算公式，对一辆实车进行的试验测量得到了可靠的数据结果，对进一步探讨转向系统刚度对汽车操纵稳定性的影响具有重要的意义。     

电动助力转向中间位置转向感觉分析

针对电动助力转向系统(EPS)的转向感觉进行了系统分析,其中转向盘中间位置的转向主观感受是汽车转向感觉研究的主要内容,直接影响驾驶员对稳定性、安全性和行驶的判断,研究通过整车中间位置转向感觉主观评价试验,介绍了试验及数据处理方法,并对客观评价指标进行了分析.分别研究了中间位置转向灵敏程度,转向手力特性,以及中间位置行驶时的汽车响应特性等三方面的客观评价指标.应用这些指标参数,可以系统全面的评定EPS中间位置转向感觉,指导EPS与整车的匹配开发,以获得更适宜的中间位置转向感觉.     

Type synthesis of function-generating mechanisms for seat suspensions

Mechanisms with “negative” stiffness are a unique tool used to significantly improve vibration isolation for a vehicle driver via upgrade of the seat suspension. However, connection of such mechanisms to the suspension results in errors in the function generation process, and in most cases, makes motion impossible. An approach to type synthesis is presented in order to make this process more predictable, easy and thus more practical for the upgrade process. Structural classification of the suspensions is presented, and -an atlas of function-generating mechanisms for suspensions that reveals the effect of “negative” stiffness is completed. All of the function-generating mechanisms appear in the atlas as result of enumeration. Structural properties of novel and existing mechanisms are compared. Finally, some advantages in practical use of novel suspensions with “negative” stiffness are illustrated.     

某新型轻卡转向系统模态对标及优化研究

转向系统模态控制是整车NVH开发的重要内容。文章针对某新型轻卡的怠速方向盘抖动问题,讨论了转向系统有限元模型的准确度影响因素,并与实测的方向盘频响曲线做对比。在模态及应变能分析结果上探讨了模态提升的主要方向,在此基础上优化转向系统主要部件,取得了较好效果。文章提供的转向系统模型对标及优化方法具有指导意义,对类似工程问题也有一定参考价值。     

电动助力转向管柱异响优化及改进

分析转向系统异响产生机理并通过主观评价及客观测试确定异响源,并针对异响源进行以减小间隙为导向的改进,对优化设计前后零部件进行对比分析,该优化设计已经经过试验验证及批量生产验证,且适用于同平台车型。     

Interior sound field refinement of a passenger car using modified panel acoustic contribution analysis

Panel acoustic contribution analysis (PACA) is a practical engineering tool for the reduction of interior structure-borne noise in passenger cars. In this study, the current PACA method has been improved for sound field refinement of the entire interior. Two new parameters, the “acoustic contribution sum” and the “total sound field contribution”, are introduced to analyze the interior sound field characterized with multiple field points and sound pressure peaks, and to evaluate the integrated acoustic contributions of auto body panels. In addition, a systematic methodology for automotive interior sound field refinement is also proposed on the basis of the modified PACA method. An example of a passenger car model demonstrates the application of the sound-field-refinement methodology and shows the advantage of using damping layers at optimum locations on the auto body. The example also shows that the modified PACA method has practical significance for refining the interior sound field and decreasing added mass in accord with the trend towards lightweight auto bodies.     

A Comparison of Alternative Obstacle Avoidance Strategies for Vehicle Control

In Alleyne (1996) several vehicle control options were considered for Unintended Roadway Departure (URD) prevention and conclusions were drawn as to the efficacy of each method. This companion paper investigates the use of several different inputs for the control of a vehicle, in the context of Obstacle Avoidance for autonomous vehicles. In this investigation, the goal of the controller is to provide an intervention in the event of the vehicle detecting an obstacle in its path. The five types of inputs that will be considered are (i) Four Wheel Steering; (ii) Front Wheel Steering; (iii) Four Wheel Brake Steering; (iv) Front Wheel Brake Steering; and (v) Rear Wheel Brake Steering. The controller design is an LQ controller based on the simplified dynamics of a 2 degree of freedom bicycle model. However, the analysis of the different strategies are performed on a more complete, nonlinear vehicle model. A key contribution of this paper is the quantitative evaluation of the relative efficiencies of each of these input strategies being examined. Unlike most control schemes, an important metric of performance is the ratio of peak tire force used versus available tire force. The conclusions reached in this paper shed additional light on appropriate input actuator methods for vehicle guidance and control.     

A Comparison of Alternative Obstacle Avoidance Strategies for Vehicle Control

SUMMARY

In Alleyne (1996) several vehicle control options were considered for Unintended Roadway Departure (URD) prevention and conclusions were drawn as to the efficacy of each method. This companion paper investigates the use of several different inputs for the control of a vehicle, in the context of Obstacle Avoidance for autonomous vehicles. In this investigation, the goal of the controller is to provide an intervention in the event of the vehicle detecting an obstacle in its path. The five types of inputs that will be considered are (i) Four Wheel Steering; (ii) Front Wheel Steering; (iii) Four Wheel Brake Steering; (iv) Front Wheel Brake Steering; and (v) Rear Wheel Brake Steering. The controller design is an LQ controller based on the simplified dynamics of a 2 degree of freedom bicycle model. However, the analysis of the different strategies are performed on a more complete, nonlinear vehicle model. A key contribution of this paper is the quantitative evaluation of the relative efficiencies of each of these input strategies being examined. Unlike most control schemes, an important metric of performance is the ratio of peak tire force used versus available tire force. The conclusions reached in this paper shed additional light on appropriate input actuator methods for vehicle guidance and control.     

Partial range scaling method based washout algorithm for a vehicle driving simulator and its evaluation

Unlike an actual vehicle, a vehicle driving simulator (VDS) has limited kinematics, workspace, and bounded dynamic characteristics making it very difficult to simulate dynamic motions of an actual vehicle. To solve these problems, a washout algorithm was developed. The developed algorithm restricts the workspace of the VDS to within the kinematic limit and makes the person driving the VDS perceive movement of an actual vehicle. However, the classic washout algorithm contains several problems, such as time delay and the generation of a wrong motion signal caused by characteristics of the filters. So the driver feels “simulator sickness,” such as fatigue, nausea, headache and so on because of differences between the sense of movement of the VDS and that of a real vehicle. In this paper, a partial range scaling method based washout algorithm, including a tilt coordination system, is developed to enhance the perception of motion and reduce simulator sickness. It is verified by a simulation, a survey, and a bio signal analysis using an electrocardiogram (ECG).     

汽车转向系统十字轴万向节传动优化设计

转向力是汽车操纵稳定性中一项重要的评价指标,其力矩波动直接影响驾驶感觉。文章对汽车转向轴的布置与力矩波动的关系进行了分析,并针对某车型转向系统的十字轴万向节结构进行优化设计。优化结果在matlab软件里仿真,得到较好的结果,波动力矩在允许的范围内。并得出最佳的中间轴相位角及轴系布置方案,对转向系统的优化设计有一定的参考价值,可作为实际车型开发中传动优化设计的技术依据。     

汽车声品质主客观评价方法研究

阐述了汽车产品开发过程中声品质主观评价方法的不足,介绍了各心理声学参数的应用。以10种类型轿车在不同车速下不同位置座椅处的耳旁噪声为评价对象,对车内噪声品质用成对比较法进行了主观评价试验;分析计算了各噪声样本的主要心理声学客观参数;在精确计算评价结果误判率的基础上,通过相关分析和多元回归分析,建立了匀速车内噪声主观偏好性与心理声学参数间的数学模型。研究结果表明,与轿车匀速车内噪声品质相关的主要心理声学参量根据车速的不同而不尽相同。     

转向驱动桥双联式万向传动轴运动学分析

转向驱动桥在整个转向过程中,对双联式万向传动轴运动做了理论分析,主要通过数值方法模拟了其不等速的变化趋势,给出传动轴在给定转角范围内,合理设计内部参数的过程,为双联式万向传动轴设计及评价提供理论参考.     

汽车转向感觉主观评价试验方法综述

传统的转向评价标准已经不能完全适应新兴的动力转向,如何系统的评价转向感觉,如何获得理想的转向感觉,已经成为国内外迫切需要解决的问题。分别对转向的移线性能、中间位置转向性能和转向的舒适性等主观感觉评价进行介绍,分析转向感觉主观评价中的几个基本问题,并探讨应用实车试验、驾驶员模型和驾驶模拟器进行转向感觉试验的主要方法,对今后转向感觉主观评价的发展具有一定指导性和借鉴意义。     

盾构掘进趋向预警值的分析和计算

盾构机利用激光导向进行掘进,前后点偏移值固然重要,但掘进趋向更为重要。当趋向值在合理的范围内时,可确保盾构隧道符合设计线形;超出预警范围,将会导致盾构严重偏离中线,造成无法挽回的损失。根据德国海瑞克盾构机在成都砂卵石地层中纠偏能力较差的现状,介绍趋向的概念、曲线段趋向的计算、盾构机实际纠偏能力的统计、趋向允许偏差公式的推导、趋向偏差预警值的确定,最后得到盾构趋向预警值。应用该研究成果在施工中加以严格控制,没有发生过隧道中线偏差超限的情况。     

A Comparison of Alternative Intervention Strategies for Unintended Roadway Departure (URD) Control

This paper investigates the use of several different inputs for the control of a vehicle, in the context of URD. In this investigation, the goal of the URD controller is to provide an intervention in the event of the vehicle leaving the road. The types of inputs that will be considered are (i) Four Wheel Steering, (ii) Front Wheel Steering, (iii) Four Wheel Brake Steering, (iv) Front Wheel Brake Steering, and (v) Rear Wheel Brake Steering. The controller design is an LQ controller based on the simplified dynamics of a 2 degree of freedom bicycle model. However, the analysis of the different strategies are performed on a 7 degree-of-freedom nonlinear vehicle model. The key contribution of this paper is the quantitative evaluation of the relative efficiencies of each of these input strategies being examined. Unlike most control schemes, the performance measure to be used will not be the output tracking error of the system. Instead, the metric of performance is the ratio of peak tire force used versus available tire force or, in other words, the actuator response relative to the maximum available actuator capability.     

SF－350型滑模式水泥混凝土摊铺机调平转向机构的原理及操作

ＳＦ－３５０型滑模式水泥混凝土摊铺机调平转向机构的原理及操作湖南省公路局曹继昌关键词：滑模式水泥混凝土摊铺机，调平，转向，原理，方向，水平，自动控制１调平及转向原理在所需铺筑路面的旁侧，按照路面施工的要求标高及路形，预先拉设一根尼龙绳。作为机器调平和...     

Disturbance compensation with a torque controllable steering system

Via a conventional steering system the driver perceives desired and disturbing effects such as road feedback and resonance effects, respectively. They appear with overlapping frequency spectra within the driver's steering torque. This paper introduces a control algorithm that is suppressing periodic disturbances without affecting useful steering road feedback attributes as well as regular power assistance characteristic. This is realised by an integrated torque actuator within the steering column in conjunction with a conventional Hydraulic-assisted Power Steering (HPS) system.     

乘用车车内噪声与主观评价相关性分析

文章选取了7辆车进行噪声舒适性主客观评价试验,客观评价指标为驾驶员耳边噪声值,主观评价指标为滚动噪声、边棱敏感性等5个,评车师根据试验情况对试验车各指标进行打分并给出总分值。比较了不同试验车速车辆前后排的噪声值,并对主、客观数值进行多元回归分析。