任意构型传声器阵列阵元坐标标定方法

A Random Array Microphone Position Calibration Method

飞机结构强度试验过程中能够准确、快速定位结构异常声源对于提供试验决策支持和及时发现试验风险具有非常重要的意义。在复杂试验环境中,根据现场具体情况任意布设传声器进行声源定位的方式更具适用性。针对飞机结构强度试验的实际需求和复杂试验环境中传声器任意布设的应用特点,进行了任意构型传声器阵列的阵元坐标标定方法研究。该方法的核心是通过声源到两个已知坐标参考传声器的真实时延和测定时延,得到时延测定的系统误差,对待标定传声器与参考传声器时延测定误差进行修正,以保证传声器坐标标定精度满足飞机结构强度试验声源定位的精度要求。以基于信号端点检测的时延算法进行传声器间的时延测定,采用优化算法进行标定方程组的求解,形成了一种适用于飞机结构强度试验复杂环境的任意构型传声器阵列阵元坐标标定方法,并在此基础上建立了一套标定流程。通过验证表明,该方法能够实现任意构型传声器阵列的阵元坐标标定,标定误差为毫米级,达到了飞机结构强度试验中传声器空间坐标标定的精度要求,为实现飞机结构强度试验中异常声源的准确、快速定位奠定了技术基础。

It is important to locate abnormal sound rapidly and accurately for decision-making support and finding test risks in aircraft structural strength test.In a complicated environment of the test,it is more suitable to arrange microphones randomly according to the situation of the test site.A microphone position calibration method for random array was presented for localization of structural damage according to the application of random microphone array in complicated environment of aircraft structural strength test.The core ideal of the method is that the time delay of arrival(TDOA)error considering velocity of sound and TDOA algorithm is obtained by real TDOA and calculated TDOA of two reference microphones.The calculated TDOA of reference microphone and unknown position microphone is corrected according to the error.Therefore,it can meet the precision requirement of sound source localization in complex environment of aircraft structural test.Signal starting point method was employed and combined with exceptional data recognition method to calculate TDOA,the calibration equations were solved by optimization method,and the technological process for microphone position calibration was built.The method was validated by calibrating a microphone’s position of an array.Result shows that the microphone’s position coordinates were calibrated accurately by the method,which is suitable to calibrate microphone position of random array in complex environment of aircraft structural strength test.The method lays the technical foundation of abnormal sound localization in aircraft structural strength test.