共查询到19条相似文献,搜索用时 140 毫秒
1.
2.
基于四立柱的台架试验是整车开发过程中可靠性评价的重要方式,当前以试验场整车载荷采集-路谱迭代的试验方式需要对每一个车型均进行实车载荷测量,存在试验周期长且产品可靠性不足时改进成本高等问题。以同一试验场可靠性规范下不同车型载荷相似性基础,开展整车四立柱台架试验载荷谱的标准化研究。分析四种车型整车四立柱台架试验载荷特征,确定各路况下不同车型同一车轮在时域、频域及损伤域的相似性,左右轮载荷时域相关及频域相干、前后轮载荷间时延特征;以同一车轮的功率谱密度分布拟合,选取覆盖一定百分位水平的功率谱作为目标重构单侧车轮时域载荷信号;综合相关和相干特征构造对侧车轮时域载荷历程;基于前后车轮时延特征,构造后轮载荷历程,最终形成整车四立柱台架试验标准化载荷谱。通过对比标准化载荷谱和实测道路谱的时域、频域、雨流、损伤,分析标准化载荷谱的合理性,以某SUV实际台架试验进行实际验证。结果表明,构造的标准化载荷谱有效复现试验场载荷下的失效情况,可为整车可靠性的快速验证提供有效手段。 相似文献
3.
4.
5.
6.
7.
《中国新技术新产品》2019,(24)
为了解读重型整车排放测试方法的相关性,对样车分别进行了道路与转毂试验研究。结果发现,在道路试验中,发动机运行工况位点较广泛分布,基本上囊括了转毂试验对应的运行工况;不管是在稳态还是瞬态工况中,道路与转毂2种试验的运行时间比例分布规律大体符合相关规范标准;在稳态工况下样车排放量都体现为市区工况最高,可能是因为在该种工况下,车辆行驶速度偏低,排气温度不符合SCR标准,以致NOx的排放量较高。 相似文献
8.
《中国新技术新产品》2020,(13)
在汽车碰撞安全性能开发中,安全气囊作为主要的乘员安全保护约束系统零部件,在汽车发生碰撞时对车内乘员安全保护方面起到了举足轻重的作用。气囊展开特性直接影响乘员头部和胸部伤害指标,因此需要发展整车点爆系统对安全气囊展开后的各项性能进行研究。整车点爆试验系统由点爆系统、滑轨系统、灯光系统、相机定位系统、环境舱以及循环水路控制系统等集成,能够简洁快速的实现安全气囊的静态展开,测试气囊的展开情况及展开飞出的碎片情况。采集气囊点爆过程的电流、电压和电阻等参数信息,为客户提供精准的试验数据。 相似文献
9.
针对某车型悬架减振器异响问题,分别进行整车道路及台架试验,获得两者的一致性规律,即减振器活塞杆加速度信号在特定频段内具有相似性。进而对减振器异响台架试验的辨识方法进行研究,提出时域峰谷差值法、分段功率谱RMS值法及基于特征能量小波分析法,并分析比较其优缺点。在此基础上提出并采用基于权重系数的聚类分析法,将单指标刚性矩形判定区域转化为多指标柔性圆形判定区域,减少评判结果因单指标误判导致最终结果误判的概率,可为大批量、不同型号减振器异响辨识及提高鉴别准确度提供参考。 相似文献
10.
为提高汽车空调系统的控制精确度和稳定性,针对变排量压缩机系统的振荡现象进行了台架和整车试验研究。通过分析实际现象和对比各种措施,分别得出了内控变排和外控变排系统的调节方法,并试着推广到双蒸发器系统。结果还表明,根据振荡发生的工况和热力膨胀阀类型的不同,调节的方法和产生的效果也有所不同。 相似文献
11.
12.
首先介绍了风量罩的测试原理及方法,风量罩测试试验台的设计原理及使用方法。本试验台的流量测量方法是采用多喷嘴流量测量方法。多喷嘴流量法具有测量流量大,耐磨损、使用范围广的特点。其次,介绍了风量罩测试试验台的组成、设计主要参数及选用的各种仪器,并结合具体工程案例说明了试验台的组成及使用方法,在所设计的试验台上进行了风量罩的测试工作,并给出了测试报告,达到了比较满意的使用效果,能为今后的工程实践提供有力的理论支持,为风量罩的年度校准提供了保障,并希望能为我国风量罩标准的制定提供参考。 相似文献
13.
14.
Characterising heave,pitch, and roll motion of road vehicles with principal component and frequency analysis
下载免费PDF全文
![点击此处可从《Packaging Technology and Science》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Michael Thomas Long Vincent Rouillard Matthew James Lamb Michael Andrej Sek 《Packaging Technology and Science》2018,31(1):3-13
For the great majority of transport vehicles, the magnitude of the heave vibration is generally more severe than pitch and roll. Consequently, the measurement, analysis, and simulation of the vehicle vibrations have been focused on vertical vibration. Despite this, it is now being increasingly recognised that the combination of heave, pitch, and roll vibratory motion can induce more severe damage to shipments than vertical vibration alone. Although the pitch and roll motion of road vehicles can now be readily measured, there is little information on how to analyse the data to produce meaningful statistical relationships between the three variables. This paper builds upon previous work that showed that there is some correlation between pitch, roll, and heave motion and that these relationships are dependent on vehicle geometry, including payload mass, centre of mass, vehicle roll centre, and moments of inertia as well as vehicle speed and the road surface. In this paper, data from a range of quasi‐controlled experiments, which involved driving vehicles at constant‐speed on selected roads, were analysed using principal component analysis as well as frequency domain analysis to reveal the relationship between heave, pitch, and roll motion. This was undertaken for a variety of vehicle speeds and routes in order to establish if they influence pitch and roll response. Results are presented in the form of distribution functions, statistical coefficients, and frequency response functions, all of which are useful for helping to define parameters for the simulation of complete, three‐axis vibrations using multi‐axis vibration test systems. 相似文献
15.
This study explores the modernization of road-based technologies for the enhancement of mobility while also implementing safer transportation. Mobility plays a critical role in everyday life on a micro and a macro scale combined. Modernization in mobility would enable establishment of a sustainable, digitalized and informed society. The inclusion of AI/ML to enhance road environment, curbing driver distraction, adopting electric vehicles, and integrating low power computing units in vehicular networks are among the potential recommendations for strengthening the evolving digital road architecture. The current ecosystem surrounding road safety and mobility can be boosted even further upon integrating products of modern technology into the classical elements of transportation. Modern technologies are classified and perceptually investigated by realizing the current challenges and proposing seamless potential extensions to the existing infrastructure from each domain. Techno-administrative concepts like the regulation of individual risk profiles for achieving a safer road environment are addressed. 相似文献
16.
为了研究路面不平度对履带车辆越野平均速度的影响规律,本文建立了履带车辆多体动力学模型,提出了振动响应指标并通过试验验证了模型的可信性;根据试验设计进行仿真计算,建立振动响应与车速、路面不平度间的近似模型;以振动响应指标的门限值为约束条件,采用目标寻优方法拟合了路面不平度与车速间的数学关系,提出了随机不平路面条件下的越野速度预测方法。应用该方法计算了车辆通过某试验场综合路面,结果表明:所建模型可以反映路面不平度对车速的影响,为车辆机动性预测提供了有效的量化手段。 相似文献
17.
18.
针对某车型悬架筒式减振器异响问题,分别进行整车路试和台架试验,在收集大量数据情况下,提出采用基于权重的聚类分析法鉴别减振器异响,并分析其中的原理。在此基础上,通过Lab VIEW虚拟仪器软件开发平台与MATLAB信号处理工具箱相结合,设计一套用于鉴别车辆悬架筒式减振器异响的测试系统,并对减振器进行异响鉴别。结果表明,该测试系统鉴别结果与减振器整车路试主观评价相关系数高于0.92,能够满足工厂企业产品质量控制方面检测要求,可为今后产品抽样检测、提高异响鉴别可靠度和改进生产过程提供参考。 相似文献
19.
Practical Considerations for Estimating Road Vehicle Frequency Response Functions from Response Data
下载免费PDF全文
![点击此处可从《Packaging Technology and Science》网站下载免费的PDF全文](/ch/ext_images/free.gif)
This paper describes the application of a practical method to estimate the dynamic characteristics (frequency response function) of road vehicles using only on‐the‐road vertical vibration response data measured during nominally constant operating speeds. While several methods exist to estimate these dynamic characteristics, they are generally either inexact or prohibitively resource intensive. A review of two analytical approaches for estimating the frequency response function of road vehicles using only on‐the‐road vibration response data is presented. The first approach is based on the assumption that the road elevation profile takes the form of a specified spectral function. The second approach is based on the random decrement technique. A practical, step‐by‐step guide to undertaking on‐the‐road vehicle vibration measurements is included and provides numerous useful tips and considerations that should be taken into account. An investigation was also undertaken into the minimum record length (i.e. fraction of road length) required to accurately estimate the dynamic characteristics of road vehicles using a Monte Carlo simulation. From the study, it was found that a minimum road length of 10 – 15 km is sufficient to obtain a reasonably accurate estimate. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献