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电容式车辆称重装置动态性能测试与分析 总被引:3,自引:1,他引:2
针对传统车辆称重装置存在的动态测量时被测车辆速度较低、测量误差较大等方面的不足,设计开发一种电容式车辆称重装置。在介绍称重装置结构设计和称重原理的基础上,对其动态性能进行测试与分析。首先从速度、加速度、振动因素对称重装置的影响进行试验测试,测试表明加速度对动态称重影响较大,而速度、振动因素对动态称重影响较小。进一步理论建模,从运动和受力角度对称重装置进行理论分析,并与试验结果相对比。试验测试和理论分析表明,电容式车辆称重装置结构简单,安装方便,抗干扰能力强,测量精度高,既适用于静态测量,又适用于动态测量,具有较好的推广价值。 相似文献
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《中国公路学报》2017,(4)
为得到山区复杂公路环境下的汽车纵向加速度特性,开展了实测总里程为3 039km的实车连续行驶试验,采集了山区双车道公路自然驾驶状态下的汽车行驶速度、轨迹、加速度等运行参数,提取了纵向加速度连续变化曲线每个波形的峰值,得到了纵向加速度的累积频率、概率分布、特征百分位值等统计分布特性,分析了纵向加速度与弯道参数和行驶速度之间的关联度和敏感性,并得到了回归关系式。结果表明:减速度累积频率曲线在某一分位值之后大于加速度,斜率突变点为第90%~95%分位,第85%分位加(减)速度值分别为0.60,0.85m·s~(-2);加(减)速度概率密度曲线均为正偏态分布,驾驶人减、加速度偏好值分别为0.17,0.25m·s~(-2);平曲线半径增大时加(减)速度随之减小,平曲线转角增加时加(减)速度随之递增,但连续弯道的递增/递减趋势要比独立弯道弱,基于第85%、第95%分位和上边界驾驶行为的减速临界半径为190,225,275m,加速临界半径为204,245,290m;行驶速度提高时加速度随之下降,至90km·h~(-1)时不再有加速行为,减速度-初速度散点数据呈不等腰三角形分布,三角形顶点对应的速度值为63.4km·h~(-1)。 相似文献
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微观交通仿真中的参数标定是科学应用仿真技术的前提.为了减少参数标定的维度,提高仿真手段工程应用效率,将微观仿真参数分为基础参数和模型参数2个部分,并设计道路工程试验方案,对部分基础参数进行工程实测研究,构建实际运动场景下车辆运行加速度取值特征及加速度-速度的关系探究.根据车辆运行过程,将车辆加速过程分为车辆起步、提速、稳定3个阶段,并依据道路实测数据,应用数据包络的方法确定加速度与速度的函数关系及取值范围.在车辆起步阶段(0~7.2 km/h),需要较大动力完成起步动作,速度低加速度高,加速度-速度斜率k=0.1832;车辆提速阶段(7.2~35.4 km/h),需要确定周边运行环境处于安全状态,加速度有一定程度减少然后逐渐上升,加速度-速度关系整体斜率k=0.0259;车辆稳定阶段(35.4 km/h以上),速度相对稳定,加速度-速度斜率约等于0.由此确定了基础参数中加速度的阈值范围,对仿真软件中默认加速度-速度关系进行优化. 相似文献
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本文主要介绍全数字式减速度运算控制器的原理和技术要求。该装置样机的特点是:(1)车轮制动减速度运算采用数字量,不用数模转换方式;(2)参数调节范围采用一个减速度值,二个加速度值的控制方式。经装车试验取得了与原理一致的试验曲线和良好的制动效果。 相似文献
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基于美国新车评价规程(US-NCAP)研究了碰撞减速度波形与乘员损伤的量化关系,建立了标准约束系统仿真模型,以一阶加速度G_1、二阶加速度G_2、动态位移D为车体结构设计指标,胸部压缩量为乘员损伤指标,分析获得了不同结构下乘员损伤指标变化规律:D不变的情况下,当G_1≤22g时,G1每增加1g,胸部压缩量降低2 mm,当G_122g时,其对胸部压缩量影响较小;G_1不变时,D每增加10 mm,胸部压缩量降低1 mm。以量化关系预测为基准,在某车型胸部压缩量优化过程中对量化关系进行了验证,结果表明,该模型预测精度为98%。 相似文献
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《汽车安全与节能学报》2014,(4)
对某反向安装儿童安全座椅的结构进行了改进设计。采用有限元-多刚体耦合的方法,依据欧洲经济委员会(ECE)的法规R44的要求,建立了改进前后的儿童安全座椅正面碰撞台车试验模型,并进行了模型验证。完成了改进后的儿童安全座椅结构正面台车碰撞实验。仿真结果表明:座椅改进后的儿童假人头部综合加速度峰值约降低15 g;胸部综合加速度超过55 g的时间缩短为2 ms;胸部垂向加速度超过30 g的时间约为2.4 ms。台车试验结果与仿真结果一致,胸部综合加速度超过55 g的时间缩短为1.7 ms;胸部垂向加速度超过30 g的时间约为2.85 ms,且台车实验中座椅结构未产生明显破坏。 相似文献
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以贵阳花溪至安顺高速公路跳花坡双线隧道为工程背景,运用Midas GTS有限元分析软件,建立了隧道爆破振动对地表影响模型。得到了地表振速和振动加速度的分布云图,并分析归纳了最大振速和振动加速度的变化规律。隧道爆破振动对地表影响的研究,可以用于高速公路隧道爆破的设计和施工作业。 相似文献
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ADAMS软件提供了柔性体模块,可真实地模拟物体的运动,文章以某轿车为研究对象,利用ADAMS仿真软件建立了带有弹性下控制臂悬架的整车模型。选择开环转向事件里的转向阶跃输入进行仿真分析,在后处理中对横摆角速度、车速、侧向加速度和纵向加速度进行分析。结果表明,柔性体悬架模型比多刚体悬架模型对车身的横摆角速度、侧向加速度、纵向加速度以及速度等具有更好的抑制作用,有利于提高汽车操纵稳定性。 相似文献
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标准 ISO 362-1:2007提出了新的测试限值和方法,但其中试验的加速入线方法尚未明确,给测试机构带来了较高的测试难度。针对此问题,基于理论分析,通过试验建立 Simulink数学模型对 M1型汽车进行研究,考虑距离和起始速度的耦合,对车辆的预加速距离和加速起始车速进行了两种不同加速方法下的预测。经试验验证,符合率为 80%,平均准确度为0.612 km/h,最低误差可达到0.2%,具有较高的准确度。该模型对于标准的执行,降低了试验的准备难度和复杂程度,一定程度填补了标准中对于加速方法的空缺。 相似文献
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为了解决汽车在仿真中加速度行驶的控制问题,基于功率平衡原理,对汽车行驶中的受力进行分析,建立汽车发动机逆模型,完成汽车加速度控制方法的建立。在matlab/simulink环境中建立汽车加速度控制算法,在汽车的加速度分别为1m/s~2,2m/s~2,3m/s~2进行仿真验证,仿真结果表明:随着行驶加速度的增加,控制器对汽车行驶速度的控制精度逐渐下降,并且速度偏差随之增大,但是基本可以保证汽车的行驶速度按照参考速度的变化趋势变化。 相似文献
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Jangyeol Yoon Dongshin Kim Kyongsu Yi 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2007,45(5):459-475
This paper presents a rollover index (RI)-based vehicle stability control (VSC) scheme. A rollover index, which indicates an impending rollover, is developed by a roll dynamics phase plane analysis. A model-based roll estimator is designed to estimate the roll angle and roll rate of the vehicle body with lateral acceleration, yaw rate, steering angle and vehicle velocity measurements. The rollover index is computed using an estimated roll angle, estimated roll rate, measured lateral acceleration and time-to-wheel lift. A differential braking control law is designed using a direct yaw control method. The VSC threshold is determined from the rollover index. The effectiveness of the RI, the performance of the estimator and the control scheme are investigated via simulations using a validated vehicle simulator. It is shown that the proposed RI can be a good measure of the danger of rollover and the proposed RI-based VSC scheme can reduce the risk of a rollover. 相似文献
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M. S. Wang N. T. Jeong K. S. Kim S. B. Choi S. M. Yang S. H. You J. H. Lee M. W. Suh 《International Journal of Automotive Technology》2016,17(1):165-173
Drowsy behavior is more likely to occur in sleep-deprived drivers. Individuals’ drowsy behavior detection technology should be developed to prevent drowsiness related crashes. Driving information such as acceleration, steering angle and velocity, and physiological signals of drivers such as electroencephalogram (EEG), and eye tracking are adopted in present drowsy behavior detection technologies. However, it is difficult to measure physiological signal, and eye tracking requires complex experiment equipment. As a result, driving information is adopted for drowsy driving detection. In order to achieve this purpose, driving experiment is performed for obtaining driving information through driving simulator. Moreover, this paper investigates effects of using different input parameter combinations, which is consisted of lateral acceleration, longitudinal acceleration, and steering angles with different time window sizes (i.e. 4 s, 10 s, 20 s, 30 s, 60 s), on drowsy driving detection using random forest algorithm. 20 s-size datasets using parameter combination of accelerations in lateral and longitudinal directions, compared to the other combination cases of driving information such as steering angles combined with lateral and longitudinal acceleration, steering angles only, longitudinal acceleration only, and lateral acceleration only, is considered the most effective information for drivers’ drowsy behavior detection. Moreover, comparing to ANN algorithm, RF algorithm performs better on processing complex input data for drowsy behavior detection. The results, which reveal high accuracy 84.8 % on drowsy driving behavior detection, can be applied on condition of operating real vehicles. 相似文献
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《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(8):1066-1098
This paper qualitatively and quantitatively reviews and compares three typical tyre–road friction coefficient estimation methods, which are the slip slope method, individual tyre force estimation method and extended Kalman filter method, and then presents a new cost-effective tyre–road friction coefficient estimation method. Based on the qualitative analysis and the numerical comparisons, it is found that all of the three typical methods can successfully estimate the tyre force and friction coefficient in most of the test conditions, but the estimation performance is compromised for some of the methods during different simulation scenarios. In addition, all of these three methods need global positioning system (GPS) to measure the absolute velocity of a vehicle. To overcome the above-mentioned problem, a novel cost-effective estimation method is proposed in this paper. This method requires only the inputs of wheel angular velocity, traction/brake torque and longitudinal acceleration, which are all easy to be measured using available sensors installed in passenger vehicles. By using this method, the vehicle absolute velocity and slip ratio can be estimated by an improved nonlinear observer without using GPS, and the friction force and tyre–road friction coefficient can be obtained from the estimated vehicle velocity and slip ratio. Simulations are used to validate the effectiveness of the proposed estimation method. 相似文献
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S. -J. Kim W. -J. Jeon J. -J. Park B. -S. Moon Y. -J. Cho Y. -I. Seo N. -K. Park K. Son 《International Journal of Automotive Technology》2011,12(6):951-958
A perturbation mark is occasionally produced on the velocity indicator of the cluster panel of a vehicle during a vehicle
collision. This mark can be used to estimate the velocity of the vehicle at the moment of the vehicle’s impact. In this study,
the effect of the impact velocity and the deceleration of the vehicle on the perturbation mark were investigated, and an analysis
of the driver’s injury was also conducted through a numerical pulse representation and computer simulations. Sled and pendulum
tests were used to replicate the conditions that produce a perturbation mark on the velocity indicator of a cluster panel.
It was verified that a higher peak acceleration is more likely than the impact velocity to cause a perturbation mark. According
to the computer simulation results, a driver’s injury could be more severe at higher peak accelerations with a constant impact
velocity. If a perturbation mark, which can be used to estimate the impact velocity, is found while investigating a vehicle
accident, this mark reveals that the acceleration was higher than that listed in the related crash report. Therefore, the
injuries of the occupants could be more serious than those expected at the reported impact velocity. 相似文献
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Jonathan Frankel Graduate Student Luis Alvarez Graduate Student Roberto Horowitz Professor Perry Li 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1996,26(4):271-299
The IVHS architecture of the California PATH program organizes traffic into platoons of closely spaced vehicles. Platoons are formed and broken up by two longitudinal control maneuvers, the merge and the split. A third longitudinal maneuver, decelerate to change lane, allows a platoon switching from one lane to another to enter its new lane at a safe spacing and speed. The maneuvers, particularly the merge, can be potentially hazardous. In a merge, the cars in the trail platoon are moving faster than those in the lead platoon, while the gap separating the two platoons is smaller than usual. A sudden deceleration by the lead platoon could cause a high-speed collision. If the relative velocities of the merging platoons can be constrained so that they are guaranteed never to collide at a high relative velocity, the merge can be considered safe. A maximum safe velocity for the trail platoon can be found for any given spacing and lead-platoon velocity. This paper presents a merge maneuver in which the velocity of the trail platoon never exceeds the maximum safe velocity. The controller switches among several feedback control laws that keep the velocity of the trail platoon inside a safe region and within comfort limits on jerk and acceleration, under normal circumstances. This merge maneuver can be considered to be the fastest merge strategy mat does not violate bounds on safety and comfort. The controller is also more robust to changes in the vehicles' acceleration capability than those that use a desired open-loop trajectory
The control approach used for the merge maneuver can be applied to the other maneuvers to ensure that they never result in a collision. The switching controllers for the split and decelerate to change lane maneuvers that are safe and yield a more comfortable ride than those that track a timed trajectory are also presented. 相似文献
The control approach used for the merge maneuver can be applied to the other maneuvers to ensure that they never result in a collision. The switching controllers for the split and decelerate to change lane maneuvers that are safe and yield a more comfortable ride than those that track a timed trajectory are also presented. 相似文献