非电传民机纵向气动参数辨识激励信号研究

Study on excitation signal of longitudinal aerodynamic parameters identification for non-fly-by-wire passenger airliners

针对非电传民机气动参数辨识时,须通过设计激励信号激发出与待辨识参数相关的飞机运动模态才能得到准确的气动参数的特点,开展了适用于非电传民机纵向气动参数辨识的激励信号设计方法研究。基于信号能量分布和幅频响应分析的信号设计方法,对激励信号进行参数设计;综合辨识效果和驾驶员的易操纵性,建议选取经参数设计后的单周期正弦信号作为非电传民机的纵向激励信号。试飞验证结果表明,所提方法能够较好地激发出飞机运动模态,使试飞数据具有较高的气动参数可辨识性。

For obtaining accurate aerodynamic parameters by identification, excitation signals should be designed properly to fully reflect the motion characteristics of non-fly-by-wire civil aircraft. According to this characteristic, excitation signals for longitudinal aerodynamic parameters identification were investiga- ted. Based on energy distribution of signals and frequency-amplitude responses, the signal parameters were designed. Combining identification results with easy maneuverability, the single cycle sinusoidal sig- nal is advised to be adopted as the excitation signal for longitudinal aerodynamic parameters identifica- tion. Flight test data for identification indicates that the method of excitation signal design can effectively excite the pertinent airplane motion mode and make the flight test data easier to identify.