微型仿生声定位结构的设计及定位方法的研究

Mechanism of a mini-instrument for sound source localization

声音定位在工程应用中具有重要的价值,常见的声定位一般是通过若干个麦克风组成的传声器阵列来实现的,各传声器单元对声激励信号产生响应而生成多个时间序列,并将其送至实现定位算法的运算单元中从而计算得到声源的位置,各传声器单元之间均独立而不相互耦合,且各传声器单元通常需保持较大的间距。这类型的声定位系统往往尺寸较大,结构较为复杂且集成度较低。本文在探索研究奥米亚棕蝇(Ormia ochracea)听觉系统定位机制的基础上,提出了一种新型的声定位装置及相应的定位理论。该仿生声定位装置的声感应部分由三个弹性振膜,以及连接三个振膜的耦合杆等力学元件组成。对该结构的动态特性分析表明:声激励的入射方向同三个振膜的响应之间存在特定的关系,通过分析两者之间的对应关系,提出了一种定位理论,该定位理论表明可通过检测并分析三个振膜的响应状况,计算得到声激励的入射角度。最后,通过实验,验证了定位方法的可靠性。同传统的传声器阵列相比,该定位结构具有微型化、集成化和结构紧凑的特点。

Sound source localization is always of great value in many engineering applications.In localization appliances,several microphone transducers are usually involved in the localization structures.Each time-domain response of these microphones under the incident sound stimulus is determined individually and sent to the arithmetic-logic sections immediately,from which the localization systems can find out positions of the sound sources subsequently.But,these appliances always consist of many components,and their structural looseness may narrow their practical applications.Here,a new type of instrument was designed to accomplish the purpose of localizing the sound source using a relatively compact structure.This bionic structure was designed to mimic the localization function of the ears of a parasitoid fly Ormia ochracea,and it consisted of three elastic diaphragms,three bars connected to the diaphragms,and the other mechanical components.The analysis of this structure's dynamic behavior showed that the incident angles of the sound have a special relationship to the responses of this instrument,and the incident angles can be estimated by detecting the vibrations of three elastic diaphragms;compared with traditional microphone arrays,this instrument has the advantage of compactness and higher integrated level.