对刚体和软体假人进行地面冲击试验,用小波方法将假人质心过载按不同频率和观察尺度分开,并分析了混沌特性参数随小波观察尺度的演化规律。对刚体假人进行高速空投试验,并用相平面分析假人质心过载与姿态的关联性。结果表明:假人质心过载波动集中在30~50Hz的低频段,软体假人对高频振荡具有良好的缓冲作用;质心过载的高频细节解随机性较大,高频干扰的误差放大率也较大,在刚体假人空投试验提取真实过载时应滤掉;高速空投试验过程中,拉直过载与开伞过载呈明显的负相关性,且开伞过载与假人的姿态角、角速度存在明显关联性,相平面中有利开伞区域为假人姿态角速度-4<α’<4rad/s,且向II、IV象限方向倾斜。
Shock test of rigid dummy and soft dummy were carried out and the overload of dummy censorial were decomposed into different temporal and frequency components using wavelet theory. The evolution of chaotic characteristics under varying temporal and frequency scales was examined as well. High-speed airdrop experiment of rigid dummy was also carried out, and the relationship between parachute-opening shock and attitude of dummy was analyzed using phase plane. Result show that the shock fluctuant energy centered in frequency range of 30~50Hz, and the soft dummy can absorb high frequency shock well. High frequency wavelet detail components are more random, in which disturbance magnification ratio is higher. So that the high frequency components should be filtered, when extract real shock value of rigid dummy. The pull-out shock and parachute-opening shock present out negative correlation. The strong dependence of parachute-opening shock on attitude angle and angular velocity of dummy indicates that there is a advantage parachute-opening area in phase plane, in which -4<α’<4rad/s and leaning towards II and IV quadrant.
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