不同车型FCW试验中TTC安全时间阈值分析

目前,在自动驾驶车辆技术中已实现量产的功能主要分布于L0-L2 (SAE标准)阶段,其中主要功能以前向碰撞预警(FCW)、车道偏离预警(LDW)、自适应巡航(ACC)以及紧急制动(AEB)等为主;针对前向碰撞预警(FCW)功能技术,目前的测试方法主要依据美国公路交通安全管理局(NHTSA)、欧盟(EU)以及国际标准化组织(ISO)制定的《FORWARD COLLISION WARNING SYSTEM CONFIRMATIONG TEST》、《ISO15623 Transport information and control systems-Forward vehicle collision warning systems-Performance Requirements and Test Procedures》等相关标准;而类似标准在设置TTC规避阈值时间(即安全碰撞时间)均设置为固定值,没有依据不同类型车辆设相关加权系数。本文根据不同车型的多次FCW试验发现,为了保证试验安全,汽车质量和TTC存在一定的相关性。本文依据不同类型车辆制动试验数据计算出相关系数,从而界定了安全的TTC阈值。

Analysis of Safety TTC Threshold in FCW Test of Different Vehicle-Models

At present,the functions of mass production in the self-driving vehicle technology are mainly distributed in the L0-L2(SAE standard)stage,in which the main functions are Forward Collision Warning(FCWs),Lane Departure warning(LDWs),Adaptive Cruise Control(ACCs)and Autonomous Emergency Breaking(AEBs).For the FCWs test,the current test methods are mainly based on the“FORWARD COLLISION WARNING SYSTEM CONFIRMATIONG TEST”,“ISO15623 Transport information and control systems-Forward vehicle collision warning systems-Performance Requirements and Test Procedures”and other related standards which are published by National Highway Traffic Safety Administration(NHTSA),the European Union(EU)and the International Organization for Standardization(ISO);These standards set the TTC to 2.4s and as a constant,and there is no weighting factor based on different vehicle models.According to the multiple FCW tests of different vehicle models,we find that there is a certain correlation between vehicle quality and TTC to ensure the vehicle safety.In this paper,the correlation coefficient is calculated based on multiple vehicle braking tests,and thus define a safety TTC threshold.