【作者】 王彦会；

【导师】 郭孔辉；

【作者基本信息】 吉林大学 ， 车辆工程， 2014， 博士

【摘要】 随着中国汽车市场的成长和重新划分，用户对车辆的性能和品质提出高要求，而以结构开发为特点的传统底盘开发，通常由设计师根据经验，确定各系统结构和性能参数，经试制、试验、改进的多轮反复，存在开发周期长、成本高、风险大的问题。如何开发满足市场用户需求的车辆，实现性能开发主导产品自主开发，成为汽车设计和性能开发关注的重点内容。为克服传统汽车开发缺陷，需要更科学的车辆开发技术，客观评价提出明确的量化指标，作为CAE仿真及优化的依据，CAE通过结构优化及性能仿真，为产品提供切实可行的改进方案，缩短开发周期。主观评价确定客观目标的优劣，代表用户通过驾乘的主观感受，设定车辆改进和优化方向，弥补CAE及客观在市场用户角度主观层面的不足。由此，主观评价、客观评价、CAE构成车辆开发三要素，其协调一致的关系决定了底盘性能及其产品的开发水平。论文立足乘用车底盘性能评价技术研究，通过搭建基于用户的主观评价体系、基于主观的客观评价体系、基于性能开发的评价技术研究以及基于主客观评价的底盘调校技术研究，尝试正确认识主客观评价及其关系，实现乘用车产品正向性能自主开发。论文主要研究内容如下：首先，通过提取市场用户驾乘操作，以车辆动力学理论进行解释并定义评价项目和术语，按照评价项目设定原则，科学搭建包含4级内容的主观评价体系框架；开展评分系统的研究，研究评分标尺对称性、方向性、量程、刻度等影响因素，引入相对评分法及不确定性选项，搭建无偏对称的10分制及相对评分结合的主观评分系统；面向主观评价能力建设，结合具体的评价场地、评价项目、评价流程及评分系统，开发主观评价工具，从而确保评价项目操作的可重复性及一致性。其次，为保证客观评价结果有效性，根据测试性质定义了环境相关的胎压设置表，结合载荷及底盘高度的设置，设定了车轮定位参数误差要求；对模拟市场用户驾乘操作的主观评价项目规范化，设置客观评价项目和评价指标；结合车辆客观评价使用的硬件、软件、规范、场地几个方面，搭建基于主观的客观评价体系框架；以搭建的客观评价体系，为主客观关系的研究及车辆性能开发提供可信、可重复的客观指标。然后，面向车辆性能开发，开展数据处理、数据挖掘、权重分析、特征提取等相关评价技术的研究。以中心区转向试验数据为例，利用独立成分分析（ICA）技术，结合主成分分析（PCA）降维处理，滤除传感器动态精度、路面干扰、主观操作偏差等噪声因素，通过数据的截取、滤波、有效性分析，提取去除噪声的更干净的有效客观数据，实现原始数据预处理；搭建多元统计主成分分析数学模型，应用于客观评价指标间内在关系的研究，通过降维并按信息量大小构建新操稳评价指标，结合因子分析模型，构建因子赋权的新指标得分公式，实现操稳综合客观评价指标百分制打分；对主观评价体系第4级主观项目的评分，使用离差最大化多属性算法，按改进的效益型决策设置决策矩阵优化目标，得到第3级评价项目得分；针对不同决策者设置平衡因子，应用群决策组合加权平均算子（CWAA）对第3级评价结果进行信息集结，得到第2级主观评价项目的多属性决策评分，同样方法得到第1级的评分，从而避免个别项目管理者的个人喜好，导致性能开发决策的人为偏颇，实现体现民主思想的多部门联合决策（群决策）主观评价目标设定。最后，结合主客观评价体系及评价技术，选择对转向和舒适性能影响显著的减振器调校开展应用研究。统计东北地区道路分布情况，利用层次划分的模糊聚类方法抽样，选取12条典型行驶路段，路谱输入减振器悬架ADAMS模型，分析减振器运动特性；设定4种驾驶操作模拟用户正常行车，通过试验测试，统计用户典型驾驶工况下减振器运动特性；得到典型高速公路上，减振器表现为小位移、0.03~0.2mm/s速度的运动特性，及典型制动工况表现为大位移小速度的运动特性；建立减振器液-固耦合模型，以台架测试获取油液特性、摩擦特性、气体反弹力数据，通过减振器拆解测试获取阀系参数，从而设置AMEPilot模型的初始参数，建立Amesim-iSight模型进行阀系参数的DOE试验优化分析，完成减振器模型的改进和参数优化，分析阀系参数灵敏度，得到各组阀系作用规律，指导减振器调校的阀系选择；通过减振器内部热传导、热对流机理分析及传热公式的推导，建立热-液-固耦合的减振器模型，研究温度对减振器油液粘度特性影响规律，发现了减振器在-15℃左右的特性拐点，论文通过对减振器0.05~0.2m/s常用工作速度的阻尼特性分析，从技术角度将供应商设定的30%偏差更改为20%，保证了底盘性能的一致性。论文通过搭建主客观评价体系，主客观评价技术及其应用，结合某款产品性能开发，在产品定义阶段应用主客观评价体系及评价技术，为产品开发设定主客观开发目标，通过目标的分解选定底盘结构及零部件性能参数；结合CAE分析，为底盘性能调校定义调校部件及范围，通过调校部件DOE分析，提供底盘柔性部件的调校方案指导；应用研发的乘用车主观评价工具，实现对轮胎、EPS等系统或总成的开发标定，并为建立主观评价数据库，开展主观评价数据挖掘提供数据支持；应用减振器模型，分析减振器阀系设置，为减振器调校提供快速指导，并对供应商提出了特性拐点及性能偏差的明确要求。通过以上产品应用，证明论文开发的主客观评价体系及评价技术能有效应用于车辆开发，实现性能开发为主导的车辆正向开发。论文主要创新点如下：1)研究底盘性能主客观评价项目，以车辆动力学术语解释市场用户驾乘操作，开发无偏对称评分系统的主观评价工具，进而通过主观项目的规范化及客观指标设置，搭建基于用户需求面、向底盘性能开发的主客观评价体系。2)基于多元统计方法及数学模型处理客观数据，提取统计学因子赋权的客观综合评价指标，基于离差最大化的多属性决策分析方法，对主观评价项目赋以权重并进行信息集结排序，完善论文搭建的主客观评价体系的评价技术。3)建立液-固耦合减振器模型，通过阀系灵敏度分析，揭示减振器阀系设置规律，建立热-液-固耦合模型研究温升特性，结合减振器运动特性的仿真和测试，提出减振器常用工作速度的性能偏差范围，实现主客观评价技术在底盘性能开发中的应用研究。更多还原

【Abstract】 Research on performance evaluation for passenger car chassis developmentAlongside with the growths and re-structures of Chinese vehicle market, it is urgent thatthe strict requirements of vehicle quality and performance be met. Nevertheless, traditionalchassis research and design, based on structure developments, rest with the experiences ofengineers who set the performance parameters and repeatedly modify the products accordingto a huge number of experiments, which leaves the problem of longer manufacturing time,high cost and risk and fails. Spontaneously, developing vehicles to meet the customers’needs and realizing independent development which stems from the performancerequirements should be taken at the first possible time.In a bid to overcome shortcomings brought out from traditional vehicle developments,engineers are confronted with big challenges on more scientific and efficient developingmethod, taking accurate parameters from objective evaluation as CAE simulation andoptimization targets; through structure optimization and performance simulation by use ofCAE, provide with more practicable improvement scheme and shorten development period;subjective evaluation, representing customers, takes driving subjective experience in toaccount to determine the function of objective target, so as to pave the way to improve andoptimize vehicle performance and remedy the defects, from the standpoint of customers,yielded from CAE and objective evaluation. Henceforth, the coordinate and concordantrelationship between subjective and objective evaluation, alongside with CAE decides theperformance of classis and development level.This paper focuses on the performance evaluation research of passenger cars’ chassis.By separately building system which bases upon subjective evaluation of customers,objective system bases on subjectivity, evaluation research bases on the development ofperformance and classis adjustment research bases on subjective evaluation, try to accuratelygrasp the relationship between subjective and objective evaluation and realize the forwarddirection independent development of passenger cars in the meantime. The main contents areas follows:First and foremost, specify evaluation items and terms via analyzing the customersdriving manipulations and vehicle dynamical philosophy; set standard and generatesubjective evaluation frame with4level rating system. Taking account the characteristics ofrating scale with symmetry, orientation, range and scale factors, then introduce relative evaluation methodology and uncertainty options to build a10points rating scale withoutoffset and subjective evaluation rating systems relative to rating combination. In order toguarantee the repeatability and consistency of the manipulation of the evaluation program,develop an evaluation software, which consider all effects of prove ground, evaluation task,rating scale and evaluation procedure.Secondly, attempting to ensure the validity of the result of the objective evaluation, tirepressure configuration meter is defined along with the loading distribution and chassisride-height configurations according to evaluation items’ function, sets the requirement andtolerance of wheel alignment. Standardize customers driving manipulation by simulation andset objective evaluation items and evaluation index. Build up objective evaluation systemfacing subjective frame based upon subjective evaluation, combining with the test facilities,data dealing computer program, test standards and proving ground. Provide reliable andrepeatable objective evaluation index for the research of the relationship between subjectiveand objective evaluation as well as vehicle performance development through the newobjective evaluation system.Furthermore, facing the development of vehicle performance, proceed data processing,characteristics abstraction, data mining, weight analysis, etc. Taking On-Center test data asan example, uses ICA technique, alongside with PAC drop dimensional processor, to filterthe dynamic precision of processor, the road surface disturbance, the deviation of subjectiveoperation and process data via interception, filtering and validity analysis to abstract morepure and effective data without noise and then pretreat original data. Build mathematicalmodel which could analysis multi-element main ingredients and used in objectivelyanalyzing the internal relationship between every index. Build handling stability evaluationindex by drop dimension and combine factor analysis model to structure new handlingstability rating formula, realizing handling stability objective evaluation rating intocentesimal grade. Using deviation maximum multi-attribute algorithm to rate the4levelsubjective evaluation system, using benefit model decision to set up decision matrixoptimization target to get third level evaluated score. Take advantage of CWAA to combinethe result of third level evaluation on balance factors set up by different decision makers, andthen get the second level subjective decision score, as the same manner to get the first levelscore to avoid individual decision makers’ preference influence the setting of subjectiveevaluation target resulting partiality caused by developers, henceforth, reflecting thedemocratic thought in the performance of joint-decision making. Last but not least, select appropriate absorber which could precious reflect the responseof steering and ride comfort and combine with subjective and objective evaluation systemand technique to develop applying research. According to the statistics of northeast roadcondition, using sampling method of fuzzy clustering hierarchy, select12typical drivingsections of railway and import ADAMS model of suspension to analyze the motioncharacteristics of absorbers. Set up4kinds of driving operation to simulate customers’ordinary driving condition to pass the test, and then count the motion characteristics ofabsorbers under several typical driving conditions. From those could get the absorber motioncharacteristics under the condition of small displacement and0.03-0.2mm/s speed andtypical braking condition which appears as large displacement and small speed motioncharacteristics. Set up absorber liquid-solid coupling model and gain liquid characteristics,friction characteristics and gas rebound data from bench test as well as the test of absorberdisassembly to set up the original characteristics of AMEPilot model and buildAmeim-iSight model to conduct the optimization analysis of the valve and then finish theoptimization of absorber, at the same time, analyze the sensitivity of valve to guide theabsorber adjustment and the design of valve. By derivate the formulas about interior heatconduction, the analysis of the mechanism of thermal convection, build heat-liquid-soliddacboevsuopiarltbiniegorns,af brasonomdr b t3he0er%nm fotiond de2l0o t%uot saatt u itndhfyel eh dcotaiwmon tp hepero vitneetml oapct erit aty1ura5ren℃ige.n f Mluof ee0an.nc0we the viscosity properties of3h~i le0,.2rmes/est, tthoe g puearrfaonrtmeea nthceeconsistency of the adjustment result.Through setting up subjective and objective evaluation system and subjective andobjective evaluation technique and applying research, associating with a certain product,using subjective and objective evaluation system and technique in the phase of productdefinition, determine development target. Cascade the targets to the performance parametersof the chassis assembles and components. Combined with CAE analysis, define the tuningparts parameters and the performance tolerance. By DOE analyzing on the compliable tuningcomponents, provides guidance for performance tuning; Apply the developed passenger carsubjective evaluation software tool(SSED), does the evaluation and calibration development,such as tire evaluate, EPS calibrate and validate etc. provide effective tools and methods tocarry out subjective evaluation database and data mining research; Apply the shock absorbermodel to analyze damper valves sensitivity and valves setting rules, adjustable shockabsorbers provide quick guidance, and vendor specific demands and performance characteristics of the damp-abrupt point; Prove the subjective and objective systems built inthe thesis can be effectively applied to the V-word development of vehicles and realizevehicle development procedure dominated by performance.The major innovation of this thesis is as follows:1. Based on the research of the subjective evaluation and objective evaluation,define the evaluation items and terminologies, which explained the customer’smanipulation and feeling with vehicle dynamical philosophy. Program the objectiveevaluation by standard some subjective evaluation items, quantity the evaluation indexes.Build up the subjective and objective evaluation system facing the chassis performancedevelopment, which satisfies the customers’ market requirements.2. Based on multivariate statistical approach to deal the objective test data, extractand analyze objective comprehensive evaluation index with statistical loading factors.Based on multi-attribute decision analysis method for maximizing deviation of thesubjective evaluation points of the project, setting statistical weight and ordering as theinformation aggregated. Establish the evaluation methods applied to the subjective andobjective evaluation system.3. Build the liquid-solid coupling shock absorber model and find the dampervalves setting rules by the sensitivity analysis of different valves compounding, analyzethe damper motion based on the piston displacement and speed using the optimizedmodel. Build heat-liquid-solid coupling model, so as to study the temperaturecharacteristics, determine the range influenced by the temperature, and then combine thesimulation and test of absorber motion characteristics, reset the damper performancedeviation, realize the subjective and objective evaluation technique application on theperformance development of chassis.更多还原