基于单目视觉的车间TTC计算及追尾危险工况特征参数研究

TTC Calculation and Characteristic Parameters Study Based on Monocular Vision

为了研究车辆追尾危险工况的特征参数,本文针对最近五年来采集到的追尾危险工况数据进行特征参数提取和分析.首先利用单目图像信息,计算危险发生过程中车辆间的碰撞时间(TTC),然后对车辆正常跟车状态下TTC值、开始紧急制动时的速度、TTC值、制动减速度和最危险时刻TTC值等参数进行统计分析.实验结果显示,有95%的追尾危险发生在45km/h以下,驾驶员制动时产生的制动减速度均值为0.51g,驾驶员正常跟车时、开始制动时、最危险时的TTC值分别为2.9s,2.0s,1.0s.

In order to study the characteristic parameters of the cases of near -crash, this paper focus on data extraction and evaluation of rear -end near-crash cases which were collected in the last five years .First, Time to Collistion（TTC） during the cases was calculated using merely information from monocular vision .Then, statistical analysis was conducted for the parameters including TTC of normal state of following vehicles , TTC and velocity of emergency braking , TTC of the most dangerous moment .Experiment results show that 95 percent of rear-end near-crashes happen below 45 km/h, and the average of braking deceleration is 0.51g, the TTC of normal following, start-braking moment and most dangerous moment are 2.9s, 2.0s, 1.0s respectively.