弹射和开伞过载测量中的频率分析

Analyse of Frequency Band in Acceleration Measurments during Ejection and Parachuting.

探讨弹射和开伞过载测量设备的频带问题。方法从人体的低频响应特性出发 ,结合弹射过载和开伞过载的具体情况 ,对测量数据采取特定处理方法进行分析。结果人体具有低频响应特性 ,频率响应低于 50Hz;弹射和开伞过载的频域在 2 0 0Hz内 ;美军标中 1 1点移动平均的处理方法 ,对信号频率成分的影响是 :小于 40Hz的成分几乎无损通过 ,40Hz与 74Hz之间的成分受到一定衰减 ,大于74Hz的成分大部分被抑制。结论当用于分析人体反应等问题时 ,采用 0～ 80Hz的低通滤波器即可 ;或采用 0～ 2 0 0Hz的低通滤波器并对测量数据进行 1 1点移动平均处理。

Objective To describe and determine the freqency band in the acceleration measurments during ejection and parachuting. Method Comprehensive review of literatures and analysis of the data procedure in the MIL S 18471G(AS). Result The human body has a low frequency response which is less than 50Hz .The frequency band of acceleration of ejection and parachuting is within 200Hz. The moving average procedure of 11 data in the MIL-S-18471G(AS) allow the frequency components below 40Hz to pass,but attenuated the frequency components between 40 and 74Hz,and supressed the frequency components over 74Hz. Conclusion When the measurments are used for the analysis of human body response, the frequency low pass filter may be 0～80 Hz or 0～200 Hz with the moving average procedure of 11 data.