提出一种在吸能管碰撞试验的基础上采用遗传算法反求材料参数的新方法。待反求的材料参数包括板材的塑性硬化参数和应变率参数。取不同碰撞速度下吸能管碰撞试验的平均碰撞力作为参考基准,将根据实际试验条件建立的碰撞仿真模型经计算得出的相应计算结果与参考基准吻合的程度定义为目标函数,采用遗传算法搜寻与试验结果相吻合的材料参数。算例表明,该方法具有较高的精度。由于吸能管碰撞试验是车辆耐撞性设计中通常必做的试验,故应用该方法反求材料的碰撞性能参数可不必进行额外的试验。
Based on crush test of the energy absorption box, an identification scheme for the determination of plastic parameters of blank sheet material was presented. The unknown parameters included the plastic harden and strain rate. The objective function was calculated using differences of the mean crush forces between the simulation and test results in different crash velocities. A genetic algorithm was employed to adjust the material parameters so that the calculated responses matched the measured ones in a least-square sense. An example shows that the accurate plastic parameters can be searched out by using this method. The crush tests of the energy absorption box are generally conducted in design of vehicle safety so no extra tests are needed in the inverse method.