基于位置信息的车辆协同碰撞预警协议

如果突然刹车、拐弯或出现故障的异常车辆能够及时地向后续车辆发送EWM(Emergence Warning Message,紧急报警信息)则可增加司机的反应时间,大大降低连环碰撞车祸的发生概率.因此,近年来车辆碰撞协同预警系统的研究受到广泛关注,为了提高EWM的传输距离,通常采用多跳广播式协同碰撞预警,传统的多跳广播很容...     

基于蒙特卡洛方法的碰撞预警系统仿真

本文提出了一种基于蒙特卡洛方法的汽车碰撞预警系统.本系统可以自动连续测量行驶车辆前方障碍物的速度和方位等数据,经过估计产生车体和目标的姿态,利用蒙特卡洛方法计算碰撞概率,发出适当的警报给驾驶员.仿真结果表明此算法能够比较精确地估计车辆的安全级别,产生相对准确的警报,为开展快速的碰撞预警系统的研究提供了一种可行方案.     

车辆碰撞信号插值补偿算法仿真

为了解决由于车辆碰撞造成的道路拥堵、连续追尾事故的发生,研究了车辆碰撞信号检测方法,以Q-L在线进化学习的车辆碰撞信号插值补偿算法为估算方法对车辆的行驶状态进行碰撞系数计算,通过在线进化的最优近似算法来寻找当前车辆行驶状态的最优插值数据区间,寻找具有最优反馈值和评价函数值的执行状态参数,从而得到车辆碰撞参数.以车辆碰撞测试中的碰撞数据和正常数据进行融合,作为仿真的输入数据,在不同信噪比下对算法的有效性进行仿真,结果表明,插值补偿算法具有较好的鲁棒性,检测率较高,误报率较低.     

基于单视觉的车辆防碰撞预警系统研究

应用单目视觉车辆防碰撞预警系统能够发识别周围车辆并估算出与其之间的距离,利用预警系统及时提醒驾驶员。解决了车道线和车辆的检测识别问题,提出了新的边缘检测算法识别道路线,然后利用特征识别算法识别车辆,并根据车辆之间的距离判定危险等级。实验结果表明,系统能够有效的识别车道线和车辆,并能很好的测量车间距,实现预警输出。     

车辆碰撞信号准确挖掘过程的仿真分析

研究车祸中车辆碰撞信号的准确检测问题.针对车辆在完成碰撞的过程中,车辆碰撞部位随机性很大,碰撞过程较短,声音信号的采样周期和间隔很小,碰撞信号与外部的干扰声音信号经常形成交叉冲突,造成瞬时碰撞信号很难被准确采集.传统的检测算法很难在碰撞中对短促碰撞信号与外界声音信号进行区分,造成检测度不高,提出了一种粗糙集神经网络的车辆碰撞声音信号检测方法.采集车辆声音信号,对信号进行预处理,从而获取粗糙集神经网络参数.建立粗糙集神经网络模型,对车辆碰撞信号进行深度挖掘检测.实验结果表明,提出的算法能够有效提高车辆碰撞声音信号检测的准确性.     

基于碰撞点时间估计的车辆碰撞预警算法

针对十字路口处的车辆碰撞现象,提出一种基于碰撞点时间估计的车辆碰撞预警算法,以降低交通事故发生概率,提高十字路口处车流的流畅程度。在考虑交通信号灯控制的情况下,分析十字路口处车辆碰撞的不同场景,并给出碰撞点位置和车辆到达碰撞点时间的估计方法。MATLAB实验结果验证了该算法的正确性和可行性,同时表明车辆速度和位置的变化都会对车辆碰撞情况造成影响。     

参数化列车碰撞平台的动力学建模与仿真

轨道车辆的设计过程中,有限元碰撞仿真方法建模复杂、修改周期长.为快速计算准确的列车碰撞响应,基于车辆-轨道耦合动力学理论,使用Matlab程序语言,建立参数化列车碰撞平台.根据实际参数,将车辆实体模型转化为数学模型,将连续轨道模型离散为弹性点支承模型;基于Hertz接触理论,使用向量法建立轮轨相互作用模型;将车钩缓冲装...     

基于毫米波雷达的车辆防碰撞预警

防碰撞预警是主动安全中的一项重要技术。提出了一种基于毫米波雷达的防碰撞预警技术。首先在MHT模型下使用毫米波雷达检测出前方车辆,然后利用毫米波雷达获取的目标的速度和距离提出了以碰撞时间(Time to Collision,TTC)作为参数的防碰撞预警机制。通过实验分析,所提出的方法能够有效地将本车与前车保持在安全不碰撞的状态,可以应用到现有的主动安全系统中。     

基于Android平台的车辆防碰撞预警系统设计

为了在行车过程中准确判断周边车辆安全距离,对危险情况及时进行预警,提醒驾驶员采取相应措施规避碰撞,基于Android平台设计了车辆防碰撞预警系统。利用CCD摄像头采集道路图像,对图像进度灰度及降噪等处理之后结合Hog特征与Haar特征进行目标车辆识别,利用单目视觉技术测算车辆间距,根据危险距离范围设定多级别预警机制。经过UAS数据集中5 561张道路图像测试,系统在晴天、黄昏、夜间等不同环境下车辆识别准确率均比较高。另外,通过设置不同车速下的危险距离,验证系统多级别预警准确。可以有效降低碰撞事故发生概率,为车辆安全驾驶提供了强有力的技术支持。     

车辆碰撞事件与碰撞损伤的检测方法

提出了一种针对车辆碰撞事件的远程检测方法. 该方法利用机器学习技术分析车辆的速度和加速度信号, 从而对车辆的行驶状态进行在线监测. 车载的前端设备实时的采集速度和加速度信号, 初步识别出可能的碰撞信号并通过无线网络发送给后台服务器. 后台服务器对碰撞信号进行准确识别, 并判断车辆的损伤程度. 论文给出了碰撞事件和碰撞损伤的检测方法, 并进行了实验测试, 结果表明该方法是有效的.     

Auditory alerts for in-vehicle information systems: The effects of temporal conflict and sound parameters on driver attitudes and performance

In-vehicle information systems will soon confront drivers with an increasing number of warnings and alerts for situations ranging from imminent collisions to the arrival of e-mail messages. Coordinating these alerts can ensure that they enhance rather than degrade driving safety. Two experiments examined how temporal conflict and sound parameters affect driver performance and acceptance. The temporal conflict of an e-mail alert occurring 300?ms before a collision warning interfered with the response to the collision warning, but an e-mail alert occurring 1000?ms before the collision warning had the opposite effect and enhanced the response to the collision warning. These results emphasize the need to consider how in-vehicle devices influence drivers' strategic anticipation of high-demand situations. Regarding sound parameters, results showed that highly urgent sounds tended to speed drivers' accelerator release, but the annoyance associated with highly urgent sounds increased workload. In fact, there was a strong positive association between ratings of annoyance and subjective workload. Consistent with the urgency mapping principle, there was a slight negative association between the differences in the rated urgency of collision warnings and e-mail alerts and subjective workload. The results suggest that warning and alert design should consider an annoyance trade-off in addition to urgency mapping.     

Auditory alerts for in-vehicle information systems: the effects of temporal conflict and sound parameters on driver attitudes and performance

In-vehicle information systems will soon confront drivers with an increasing number of warnings and alerts for situations ranging from imminent collisions to the arrival of e-mail messages. Coordinating these alerts can ensure that they enhance rather than degrade driving safety. Two experiments examined how temporal conflict and sound parameters affect driver performance and acceptance. The temporal conflict of an e-mail alert occurring 300 ms before a collision warning interfered with the response to the collision warning, but an e-mail alert occurring 1000 ms before the collision warning had the opposite effect and enhanced the response to the collision warning. These results emphasize the need to consider how in-vehicle devices influence drivers' strategic anticipation of high-demand situations. Regarding sound parameters, results showed that highly urgent sounds tended to speed drivers' accelerator release, but the annoyance associated with highly urgent sounds increased workload. In fact, there was a strong positive association between ratings of annoyance and subjective workload. Consistent with the urgency mapping principle, there was a slight negative association between the differences in the rated urgency of collision warnings and e-mail alerts and subjective workload. The results suggest that warning and alert design should consider an annoyance trade-off in addition to urgency mapping.     

Human performance models and rear-end collision avoidance algorithms

Collision warning systems offer a promising approach to mitigate rear-end collisions, but substantial uncertainty exists regarding the joint performance of the driver and the collision warning algorithms. A simple deterministic model of driver performance was used to examine kinematics-based and perceptual-based rear-end collision avoidance algorithms over a range of collision situations, algorithm parameters, and assumptions regarding driver performance. The results show that the assumptions concerning driver reaction times have important consequences for algorithm performance, with underestimates dramatically undermining the safety benefit of the warning. Additionally, under some circumstances, when drivers rely on the warning algorithms, larger headways can result in more severe collisions. This reflects the nonlinear interaction among the collision situation, the algorithm, and driver response that should not be attributed to the complexities of driver behavior but to the kinematics of the situation. Comparisons made with experimental data demonstrate that a simple human performance model can capture important elements of system performance and complement expensive human-in-the-loop experiments. Actual or potential applications of this research include selection of an appropriate algorithm, more accurate specification of algorithm parameters, and guidance for future experiments.     

基于ADS-B的飞机预警避撞算法研究

为解决引入广播式自动相关监视技术(ADS-B)后飞机密度加大带来相撞概率增大问题,提出了一种基于ADS-B的飞机预警防撞算法.该算法将飞行冲突区域分为保护和避碰区域,冲突告警分为低级、保护区域和避碰区域告警.该算法有效利用ADS-B提供的数据,在本机的垂直和水平方向分别设计了合理的保护和避碰区域的预警防撞空间和时间门限...     

汽车碰撞预警主动安全预测方法

汽车主动避撞系统的研究主要是为了能够提前对汽车碰撞做出预警及自动处理,有效抑制交通事故的发生。文中开展基于摄像头、激光雷达、车间通信的车辆防碰撞预警关键技术研究,提出了一种适用于智能车超车换道阶段的基于TTC和冲突概率估计的碰撞概率主动安全预测算法。综合考虑时间域和超车距离等条件的约束,建立车辆超车换道最小安全距离模型;依据超车行为约束条件,提出碰撞时间与碰撞概率的公式(TTC);同时引入多元高斯分布的概率密度函数,用冲突潜在领域表示潜在冲突的可能性大小,建立了两车潜在冲突区域重合的概率密度计算模型。在1∶10模拟赛道仿真平台上对所提方法进行了模拟测试,其对4辆智能车200次的同向及反向接近预警警报和紧急警报的准确率均为100%,从而验证了该方法的有效性。     

A comparison of tactile, visual, and auditory warnings for rear-end collision prevention in simulated driving

OBJECTIVE: This study examined the effectiveness of rear-end collision warnings presented in different sensory modalities as a function of warning timing in a driving simulator. BACKGROUND: The proliferation of in-vehicle information and entertainment systems threatens driver attention and may increase the risk of rear-end collisions. Collision warning systems have been shown to improve inattentive and/or distracted driver response time (RT) in rear-end collision situations. However, most previous rear-end collision warning research has not directly compared auditory, visual, and tactile warnings. METHOD: Sixteen participants in a fixed-base driving simulator experienced four warning conditions: no warning, visual, auditory, and tactile. The warnings activated when the time-to-collision (TTC) reached a critical threshold of 3.0 or 5.0 s. Driver RT was captured from a warning below critical threshold to brake initiation. RESULTS: Drivers with a tactile warning had the shortest mean RT. Drivers with a tactile warning had significantly shorter RT than drivers without a warning and had a significant advantage over drivers with visual warnings. CONCLUSION: Tactile warnings show promise as effective rear-end collision warnings. APPLICATION: The results of this study can be applied to the future design and evaluation of automotive warnings designed to reduce rear-end collisions.     

基于无线通信的车辆主动防撞预警系统设计

提出了一种基于无线通信的车辆主动防撞预警系统,利用梯度方向直方图特征与支持向量机配合单目测距模型实现前方车辆的实时检测与测距,并利用传感器无线通信网络获取相对车速信息,最后根据相对车距与相对车速配合TTC预警模型实现碰撞预警。试验结果表明,系统平均处理时间100ms,车辆检测准确率95%,单目测距误差小于±4m,实现了实时、准确的车辆预警。     

Design and research of automobile anti-collision warning system based on monocular vision sensor with license plate cooperative target

At present, detection method for the target vehicle based on monocular vision sensor uses the whole vehicle as targets. The automobile anti-collision technology proposed in this paper adopts monocular vision sensor for automobile measurement based on vehicle license plate cooperative target. Monocular vision sensor has advantages of good real-time performance and low cost. The technique can improve the detection capability of vehicle collision avoidance warning systems. In addition to the target vehicle positioning, it can also realize attitude determination. This technology eliminates the limits of road surface roughness and fluctuation. This paper designs the realization scheme of collision warning system based on monocular vision sensor from the automobile license plate cooperative target. Technology roadmap of automobile collision warning system is given. In this paper, license plate frame location is as the research background. The paper presents an analytic solution of positioning method for the license plate frame image. The method uses four vertex characteristics of license plate frame image to locate. Positioning speed of the method is fast. And it has a unique solution. This method can be used to positioning for the license plate frame. Simulation experiment is done for the collision warning location. The simulation results show that this method can locate the position for license plate frame image. License plate is regular shape, uniform, with identity recognition function markers on the automobile body. In the previous research on automotive collision warning and intelligent vehicle, we have not seen the research methods similar to the method introduced in this paper. The research enriches automobile anti-collision technology and theory of intelligent vehicle technology. It can also provide an auxiliary method for navigation and obstacle avoidance research for unmanned vehicle. It has certain scientific significance. Vehicle collision warning system can help the driver judgment, prompting warning, improving driving safety, and has broad application prospects.     

Economic design of variable sampling intervals T2 control charts using genetic algorithms

Control charting is a graphical expression and operation of statistical hypothesis testing. In this paper, we develop the economic design of the variable sampling intervals (VSI) T² control chart to determine the values of the five test parameters of the chart (i.e. the sample size, the long sampling interval, the short sampling interval, the warning limit, and the control limit) such that the expected total cost, associated with the test procedure, is minimized. The genetic algorithm (GA) is employed to search for the optimal values of the five test parameters of the VSI T² chart, and an example is provided to illustrate the solution procedure. Sensitivity analysis is then carried out to investigate the effects of model parameters on the solution of the economic design.     

基于车内外视觉信息的行人碰撞预警方法

行人碰撞预警系统通常依据行人检测与碰撞时间判断的方式为驾驶员提供预警信息。为了提供更加可靠的危险判断依据，本文提出一种同时分析道路状况与驾驶员头部姿态的行人碰撞预警方法，用两个单目相机分别获取车辆内外环境图像。通道特征检测器用于定位行人，根据单目视觉距离测量方法估计出行人与自车间的纵向与横向距离。多任务级联卷积网络用于定位驾驶员面部特征点，通过求解多点透视问题获取头部方向角以反映驾驶员注意状态。结合行人位置信息与驾驶员状态信息，本文构建模糊推理系统判断碰撞风险等级。在实际路况下的实验结果表明，根据模糊系统输出的风险等级可以为预防碰撞提供有效的指导。