汽车追尾碰撞主动头枕数学模型的建立与分析

Establishing and Analyzing the Mathematical Model of Active Headrest in Rear End Collision

追尾碰撞事故易导致前车乘员的挥鞭伤,从而造成一定的社会经济损失。根据生物力学的研究成果,在追尾碰撞发生时,适度减小头枕与头部的水平距离可以降低挥鞭伤的程度。为弥补传统纯机械主动头枕响应滞后的不足,采用机电结合的方法,根据感知系统提供的信息,判断行驶安全性,并提前启动主动式头枕,从而保护乘员。根据主动头枕的控制策略,提出头枕控制的算法流程,并建立了追尾碰撞的数学模型,得出前后车不同行驶状态下的最小安全距离表达式,分析了模型中关键参数的随机性与动态性;借助安全裕度开关指标实施控制操作,并以算例进行验证。

The front seat occupants of vehicle may suffer the whiplash injury caused by rear end collisions, and which could be a certain socio-economic losses. According to the result of biomechanical research, appropriately de- creasing horizontal distance between head and headrest may reduce the risk of cervical spine injury during a rear end collision accident. In order to cover the shortage of traditional mechanical active headrest, due to its long response time, both mechanical and electronic methods are used in this project. Based on the information provided by sensing system, so the driving safety can be determined and the active headrest can be actuated ahead of an accident to protect the occupants. In terns of the control strategy of active headrest, the algorithms flow of headrest control is proposed and a mathematical model of rear end collision is established. Moreober, under the different conditions of both front and rear cars, the minimum safe distance expression is obtained and randomness and dynamic of the key parameters in mod- el are analyzed. With the safety margin switch indicator the control operations can be implemented, and which can be validated by numerical example.