飞机结构强度试验异常声源信号提取方法研究

摘要

针对飞机结构强度试验环境复杂的特点,进行了飞机结构异常声源信号提取方法研究.采用经验模态分解方法进行声源降噪处理,通过Teager能量算子加短时过零率的双参数双门限法,进行带噪信号的端点检测,形成了一套飞机结构强度试验异常声源信号提取方法.通过提取复材板断裂和铆钉断裂等飞机真实结构的异常声源信号,对该方法进行了验证.结果表明,该方法能够在含背景噪声的信号中准确提取飞机结构异常声源信号,适用于飞机结构强度试验复杂环境中的异常声源信号提取.同时,为实现飞机结构异常声源快速定位和声源特征辨识奠定了技术基础.%An aircraft structural exceptional sound sources signal extraction method was presented according to the complex environment of aircraft structural strength test.Empirical mode decomposition was employed to reduce noise, two-parameter and dual-threshold method was employed to detect endpoints of signals with Teager energy operation and short-term zero-crossing rate.The method was validated by extracting real aircraft structure exceptional sound sources signal.The result shows that the structure exceptional sound sources signal is extracted accurately by the method, and it is suitable to extract exceptional sound sources signal in complex environment of aircraft structural strength test.It also lays a foundation for realizing exceptional sound sources localization and characteristic recognition of aircraft structure.