考虑驾驶员反应时间的车辆碰撞预警模型

为了保证车辆在行驶过程中的安全性,提出了一种考虑驾驶员反应时间的车辆碰撞预警模型,改进了传统模型中驾驶员反应时间定值化的缺点。首先,依据车辆的制动过程分析了驾驶员反应时间对制动距离的影响。其次,设计驾驶员反应时间的模糊推理算法,选取驾龄、疲劳强度和应变能力3个主要因素作为评价指标来计算反应时间。最后,采用分等级的预警策略建立考虑驾驶员反应时间的碰撞预警模型,并通过Carsim-Matlab/Simulink联合仿真与传统模型进行对比分析。结果表明,设计的预警模型可以对不同类型的驾驶员进行差异化碰撞预警,在30 km/h和80 km/h两种车速下实际停车距离与理论值的最大误差为8%。

A warning model for vehicle collision on account of the reaction time of the driver

The paper is inclined to propose a vehicle collision warning model on account of the driver’s reaction time,which can help drivers to overcome the disadvantage of the reaction time in a sense of the traditional model. As a matter of fact,the vehicle collision warning model we have proposed is to ensure the safety of vehicles in the process of driving,which helps to overcome the disadvantage or inefficiency of the driver’s reaction time fixed data in the traditional sense. And,for the said purpose,first of all,the paper has made an analysis of the detailed process of braking measures to be taken when an emergency to the vehicle driver comes out. The time of the process braking may include 4 moments: the reaction time of the driver,the moment for the brake coordination,the time increase for deceleration of the braking action and the braking time prolonging. And,then,we have also pointed out the effect of the driver’s reaction time on the vehicle braking distance. What is more,since the driving feature of each driver can be different,their reaction time may be different,too. And,in turn,if the driver’s reaction time is different,it would be natural for the collision warning deviation to come about. And,secondly,we have chosen the drivers’ driving age,the fatigue strength and the strain extent or degree as the assessment indexes. At the same time,it is also necessary to designate the fuzzy reasoning algorithm of their reaction time on the basis of the relevant literature consultation. And,so,in this paper,we have built up a fuzzy inference rule for accounting their reaction time,so that their reaction time can be worked out in accordance with their individual driving features or styles.Thus,eventually,when considering the vehicle collision warning system and the active braking system,it would be necessary to build up a hierarchical vehicle collision warning strategy,and establish a vehicle collision warning model on account of the driver’s reaction time. Thus,it can be seen that,through the joint simulation of Carsim-Matlab/Simulink,the early warning model can be proposed here in the paper in comparison with the traditional model with no account of the driver’s reaction time. Rather,we prefer to simulate at the 30 km/h and 80 km/h speeds,driver 1,driver 2 and traditional models under the set AEB operating conditions respectively,by bringing driver 1,driver 2 respectively under the set AEB operating conditions. The results of our study and examination show that the collision warning model we have initiated in this paper can help to overcome the disadvantage of the fixed length of the driver reaction time in the traditional model. It can thus differentiate the collision warning for the different types of drivers and ensure the safe driving of the vehicles. Say,at the speeds of 30 km/h and 80 km/h,the maximum error between the actual parking distance and the theoretical account is merely a gap of 8%.