车辆高速碰撞中均匀乘员约束与乘员碰撞响应的影响规律研究

As technologies of intelligent traffic and autonomous driving progress, small lightweight cars travelling in platoon at high speed and small distance between cars might become a normal traffic mode in future. Although these technologies may help greatly reducing traffic accident rate, the traffic mode of high-speed platoon cars is expected to result in more high-speed multi-car collisions, due to problems of network security and reliability as well as failure risks of vehicle components and driving environments. Meanwhile, different seating environments and more flexible occupant postures may appear in autonomous vehicles, which is another challenge to occupant impact protection and existing occupant restraint system...On the other hand, improved technologies in pre-crash sensing and occupant state monitoring may provide more possible means for controlling occupant posture and executing tailored occupant restraint force. In this study, for given impact conditions and given injury severity levels of occupant, we will first identify ideal occupant posture and ideal occupant restraint, study coupling relation between these states, and determine the most severe but survivable crash severity. Second, by getting key idea from driver restraint devices in racing cars for high-speed impact protection, which is using well-distributed restraint forces for better controlling occupant posture and response, we will put forward some innovative restraint concepts, devices and configurations for future cars, that can provide individualized protection to occupants of different statures and postures, and under different crash severities.

随着智能交通和车辆自动驾驶技术的发展，未来交通环境下将出现以小型轻量化车辆为主的小车距、高速队列化行驶模式。在大大降低碰撞事故率的同时，受制于网络安全、汽车部件与道路环境的可靠性，预计多车高速碰撞事故的占比会增大。同时，车内乘坐环境与乘员姿态也将产生明显变化。传统的乘员约束系统尚未考虑未来交通环境将带来的挑战。本项目拟面向未来交通环境特点，对给定的乘员伤害控制目标，找出理想乘员姿态、理想乘员约束与最大碰撞强度之间的关系及相互影响规律，研究并确定乘员能承受的极限碰撞工况；并以此为基础，借鉴赛车中通过均匀化乘员约束力和控制乘员运动姿态来应对复杂和高速碰撞条件的思想，提出新型的乘员约束形式并确定相关的构型配置和调整方式；同时，随着碰撞预判信息准确度的不断提升，设计新型约束系统使之能对更严重的碰撞强度以及多种乘员身材特征和乘坐姿态提供有针对性的保护。

随着智能交通和车辆自动驾驶技术的发展，未来将出现小车距、高速、队列化车辆行驶模式下的碰撞事故形态，车内乘坐环境与乘员姿态也将产生明显变化，传统的乘员约束系统尚未考虑未来交通环境将带来的挑战。面向未来的交通模式和乘坐环境，本项目分析了车辆参数与队列参数对小间距队列高速行驶模式下碰撞严重性的影响，调研了自动驾驶车辆里的乘坐环境和姿态倾向；在不同碰撞强度的前碰撞、不同初始坐姿的情况下，评估现有乘员约束系统保护效果，并提出基于现有约束系统实现针对乘员体型多样性的参数优化策略；提出了理想的乘员约束形式并验证了其保护效果，并揭示了理想约束形式下乘员姿态和碰撞强度对乘员响应的影响规律和机理；进行了新型乘员约束形式的机械结构设计，并进行原理样机制作。研究结果表明，通过优化行驶队列中的车辆排布可以降低队列行驶车辆发生碰撞事故时的整体碰撞强度。乘员对未来乘车姿态和环境的偏好受年龄、性别、教育水平、地域的影响，且后倾坐姿和可调朝向座椅将受到青睐。现有约束系统下，乘员身体各部位损伤风险与碰撞工况、约束系统配置、乘员姿态和体型参数之间的关系可用二次函数表示，且碰撞速度和身体质量指数（BMI）分别对头部和胸部损伤有显着影响。基于现有安全带和气囊装置的乘员约束系统，通过调整气囊充气质量流速这一单个参数，即可实现对中美体型乘员保护的切换。从约束形式的角度，均衡约束下的胸腔变形模式可以充分利用人体的承载能力，使得针对较高碰撞强度、较强壮人体设计的约束系统参数配置，在低速碰撞下及对弱势群体乘员也可以实现有效保护。增强膝部约束、减弱躯干约束，能够对后倾姿态乘员提供较好的保护。而乘员后倾坐姿和高碰撞强度都存在增大脊椎压力和内脏变形的固有风险。本项目的研究为未来自动驾驶队列车辆的排布策略、现有约束系统的优化和未来新型约束系统的设计、未来结合主被动安全技术提升汽车碰撞安全性提供了参考。