抛投式机器人高过载弹射泡沫塑料的共振吸能特性

Resonance and energy-absorption capability of polyurethane foam in high-shock launching for scout-robot

针对抛投式机器人弹射过程中存在的高过载问题,使用缓冲材料对机器人进行减过载处理。讨论了缓冲材料在高过载情况下的吸能特性,根据抛投式机器人缓冲保护壳的结构和缓冲材料的性质,建立了单自由度支座激励系统数学模型,并对其系统固有频率和放大系数进行了分析。利用弹射器内弹道加速度测量系统测量了弹射器的激励曲线和机器人在缓冲材料作用下的响应。实验结果表明,当缓冲系统的固有频率与弹射器的激励频率接近时,系统产生共振,机器人所受过载增加。通过调整缓冲系统的参数,改变其固有频率,使系统放大系数小于1,避免产生共振。

For solving the high-overload problem existing during launching the scout-robot, the polyu- rethane foam was used as cushion material to reduce the overloads endured by the scout-robot. The energy-absorption capability of the polyurethane foam in the high-shock launching was discussed. Based on the structure of the robot protection shell and the properties of the cushion material, a math- ematical model was established for the base-excited system with single degree of freedom. And the natural frequency of this system was analyzed as well as its amplification coefficient. An interior bal- listics measurement system was developed to measure the acceleration curves of the scout-robot with and without cushion. The experimental results show that the system can produce resonance to make its acceleration increase when the natural frequency of the system is close to the excitation frequency of the launching device. And the natural frequency of the cushion system can be changed by adjusting the system parameters to reduce the amplification coefficient to less than 1 and thus the cushion sys- tem can avoid resonance.