在正面碰撞车体结构和乘员约束系统设计中，需要把复杂的减速度拟合成简化的波型以利于进一步分析和研究。通过计算ESW、TESW和EDTW三种简化波型,得出 EDTW积分得到的速度和位移曲线与实际曲线拟合的最好；同时比较了基于ESW、TESW和EDTW的胸部减速度，基于TESW的胸部减速度峰值与实际胸部减速度峰值最接近。提出采取EDTW包络线和取TESW平均值方法来设计目标车的思路，利用组合“拟合”方案，进行基于EDTW的车体结构设计和基于TESW的乘员约束系统设计。结果表明：简化的拟合波型TESW和EDTW都有各自的优势可以用来指导目标车正面碰撞安全的初步设计，使得胸部减速度符合设计的目标。

In the safety design of vehicle structure and occupant restraint system upon frontal impact, the complicated deceleration should be fitted into a simplified wave. In this paper, three simplified waves including equivalent square wave （ESW）, tipped equivalent square wave （TESW） and equivalent double-trapezoid wave （EDTW） are investigated, finding out that the velocity and displacement curves integrated from EDTW accord well with the actu- al ones, and that the chest deceleration peak based on TESW is most close to the actual one. Moreover, a scheme of designing the objective vehicle using the wrap around line of EDTW and the average of TESW is presented. With this scheme, both the vehicle structure based on EDTW and the occupant restraint system based on TESW are designed. It is found that the simplified fitted waves TESW and EDTW can be well applied to the primary safety design of objective vehicle upon frontal impact to satisfy the demand of chest decelarntion