试验室检测测量不确定度的评定方法

文章对针对汽车检测领域检测结果的测量不确定度来源进行分析,并归纳了几套适用性强的评价计算方法,对该领域的测量不确定度评定具有一定的指导意义。     

百分表示值误差的测量结果不确定度

本文根据国家计量技术规范JJF1059—1999《测量不确定度评定与表示》中规定的通用规则，在跃进汽车集团技术中心计量室现有检测环境、计量标准、设备的基础上，以1级百分表10mm点示值误差的测量／校准为例，分析测量不确定度，给出测量结果不确定度报告。     

平晶标准装置测量不确定度的分析

通过对平晶标准装置的测量不确定度各分量的分析、合成，得到整个标准装置的扩展不确定度、自由度。     

不确定度评定在汽车燃料消耗量检测中的应用实践

不确定度评定是目前国际上对测量结果进行评价的主要方法之一，通过对汽车燃油消耗量检测过程中的不确定度来源进行分析，提出了可操作的评价方法。并结合具体实践得出对该检测项目有指导意义的不确定度评价结果。     

汽车车外加速噪声的检测及不确定度分析

论述了汽车车外加速噪声的检测、影响噪声测定值的因素及不确定度分析。     

测量不确定度在交通工程试验检测数据处理中的应用

文章主要介绍测量不确定度的定义及内容,结合交通工程试验检测的实际,如何使用测量不确定度对试验数据进行处理,依据检测结果做出科学准确的结论     

测量不确定度及其在工程试验检测中的应用

介绍了测量不确定度的定义、应用范围、来源、分类及数学模型的建立.通过砼试件抗压强度试验的不确定度评定实例,阐述了不确定度在工程试验检测中的应用及意义.     

常温排气污染物检测结果测量不确定度评定

本文根据国家轻型车污染物排放标准和测量不确定度评定规范,对常温下冷起动后排气污染物排放的试验结果进行测量不确定度的评定和分析。     

汽车整车音效设计及评价方法

随着人们生活水平的提高,对车载音响的品质要求也越来越高,评价整车音响效果的方法也很多,该文主要介绍频响曲线辅以主观听音来对整车音效进行评价,通过对结果的分析,可以对整车音效后期的改善起指导性作用。     

GB 38900-2020机动车安全技术检验项目和方法解析

文章总结了GB38900-2020与GB21861-2014、GB 18565-2016关于车辆安全技术检验项目和方法上的主要差异.包括标准名称、检验方法、检验要求、结果判定、检验项目等,希望能为相关人员提供参考.     

Experimental evaluation of a vehicle steering assist controller using a driving simulator

Human-in-the-loop driving simulator experiments are conducted to evaluate a proposed robust steering assist controller that is designed on the basis of driver uncertainty modelling. A nominal controller (NC) that is designed without consideration of driver model uncertainty is also tested for comparison. Two types of experiments are proposed: a long driving task with nominal configurations and a short driving task with initially large lateral position error. The data are analysed using both time domain and frequency domain metrics. In the time domain, the standard deviation of lateral position error and percentage of road departure are used. In the frequency domain, the stability margins and crossover frequency are used. The driving simulator results indicate that statistically, the designed robust controller shows improvements in the short driving experiments. The improvements in the long driving experiments are less evident because of driver adaptation. The non-robust NC suffers from high gain and should be avoided. The benefits of considering driver model uncertainty in the design of vehicle steering assist controllers are, therefore, justified.     

瑞雷面波法在路基质量检测中的应用

通过瑞雷面波法在内蒙古呼集高速公路路基病害调查中的工作实例、现场工作方法,论述了该技术在高速公路路基质量检测中的应用前景及推广价值。     

汽车热式空气流量计测量电路分析与实车检测

为详细说明热式空气流量计的具体工作原理,重点分析了热式空气流量计的实际测量电路,并对温度补偿进行了适当说明,介绍了CORALLA轿车的空气流量计,利用BOSCH—FSA740发动机性能分析仪对其进行检测,得出了不同转速下的信号电压。     

A new formulation of the understeer coefficient to relate yaw torque and vehicle handling

The handling behaviour of vehicles is an important property for its relation to performance and safety. In 1970s, Pacejka did the groundwork for an objective analysis introducing the handling diagram and the understeer coefficient. In more recent years, the understeer concept is still mentioned but the handling is actively managed by direct yaw control (DYC). In this paper an accurate analysis of the vehicle handling is carried out, considering also the effect of drive forces. This analysis brings to a new formulation of the understeer coefficient, which is almost equivalent to the classical one, but it can be obtained by quasi-steady-state manoeuvres. In addition, it relates the vehicle yaw torque to the understeer coefficient, filling up the gap between the classical handling approach and DYC. A multibody model of a Formula SAE car is then used to perform quasi-steady-state simulations in order to verify the effectiveness of the new formulation. Some vehicle set-ups and wheel drive arrangements are simulated and the results are discussed. In particular, the handling behaviours of the rear wheel drive (RWD) and the front wheel drive (FWD) architectures are compared, finding an apparently surprising result: for the analysed vehicle the FWD is less understeering than for RWD. The relation between the yaw torque and the understeer coefficient allows to understand this behaviour and opens-up the possibility for different yaw control strategies.     

汽车传动系统悬置的优化设计

建立汽车传动系统悬置的数学模型,并确定悬置系统隔振评价指标。通过对某汽车悬置系统的刚度的优化设计,系统固有频率稍有增加。各方向振动解耦度均大于90%。动力传动系统悬置y方向位移在3mm左右,较刚度匹配前的7.7mm大幅减小,悬置隔振效果大大提高。     

A vehicle stability control strategy with adaptive neural network sliding mode theory based on system uncertainty approximation

Modelling uncertainty, parameter variation and unknown external disturbance are the major concerns in the development of an advanced controller for vehicle stability at the limits of handling. Sliding mode control (SMC) method has proved to be robust against parameter variation and unknown external disturbance with satisfactory tracking performance. But modelling uncertainty, such as errors caused in model simplification, is inevitable in model-based controller design, resulting in lowered control quality. The adaptive radial basis function network (ARBFN) can effectively improve the control performance against large system uncertainty by learning to approximate arbitrary nonlinear functions and ensure the global asymptotic stability of the closed-loop system. In this paper, a novel vehicle dynamics stability control strategy is proposed using the adaptive radial basis function network sliding mode control (ARBFN-SMC) to learn system uncertainty and eliminate its adverse effects. This strategy adopts a hierarchical control structure which consists of reference model layer, yaw moment control layer, braking torque allocation layer and executive layer. Co-simulation using MATLAB/Simulink and AMESim is conducted on a verified 15-DOF nonlinear vehicle system model with the integrated-electro-hydraulic brake system (I-EHB) actuator in a Sine With Dwell manoeuvre. The simulation results show that ARBFN-SMC scheme exhibits superior stability and tracking performance in different running conditions compared with SMC scheme.