卫星主动段动力学环境数据分析

某型号小卫星发射时，用搭载的测量系统对星上6个测点位置进行了3个方向的振动响应测量，获得了主动段2000Hz范围内的完整数据。数据分析表明，小卫星主动段的振动模态特性和振动响应特性不同于地面模拟试验中的结果，主要体现在：主动段40Hz处的Pogo效应明显；共振频率与地面试验完全不同；横向响应量级明显小于纵向响应量级；在小于2000Hz频率范围内，星箭分离冲击对星上测点位置影响很小。与地面试验数据的对比分析结果表明，目前的地面振动试验方法仍有不足，存在过试验或欠试验。

Analysis of satellite dynamic environment data at powered-flight phase

The vibration responses in three directions at six locations on a small satellite were measured with an on-board measurement system within a range of 2000 Hz. The analysis of the measurement data shows that the vibration modal characteristics and the vibration responses of the satellite at the powered-flight phase are different from those in the ground vibration test, the Pogo effect at 40 Hz is obvious, the resonant frequency is different, the horizontal response level is less than the longitudinal one, and the shock effect of the satellite-rocket separation is very small in the range of 2000 Hz. The comparison analysis shows that the ground vibration test method should be improved.