为了应对空间碎片的威胁, 研制了一种基于声发射技术的用于实时监测空间碎片撞击航天器的在轨感知系统。对平面声发射源精确定位技术提出了需求。声发射信号属于非平稳随机信号, 传统的小波变换无法充分获得其中携带的信息。利用HHT技术分析声发射信号波形, 改进了A0模态到达时刻的确定算法, 提高了线定位精度。在此基础上, 将平面定位问题转化为求取函数最小值的优化问题, 并利用单纯形法进行求解。在铝合金板上对铅芯折断波源进行了定位试验, 结果表明, 相对于小波变换, HHT更适于分析声发射信号; 改进后的线定位方法和双时标法可有效应用于各向同性板的定位问题。研究结果为空间碎片在轨感知系统的研制提供了参考。

To response the threats of space debris, the space debris sensing system in orbit is employed to monitor the impact events. A system based on acoustic emission(AE) technique gets great attention, this promotes a demand for pinpoint method for AE source location. AE waveform is non-stationary and random, wavelet transform is not suitable to its analysis. Hilbert Huang Transform(HHT) is utilized to analyze the AE waveform, utilizing an improved algorithm for computing arrive time of A0 mode wave, the linear source location precision is improved. A bivariant function is used to present the planar location problem, and the simplex method is used to solve the problem. Experiments have also been carried out on aluminium alloy sheets using a lead-break AE source. The experimental results indicate that: HHT is more suitable to analyze the AE waveform, the improved liner location method and the planar location method can be used in the isotropy sheets effectively. The result provides a reference for the development of the sensor systems to detect impacts on spacecraft.