骨導式助聽器植入端分析

Implantable vibrator structure analysis for bone conduction hearing aids

蔡繼揚(Ji-Yang Tsai)

指導教授 ： 蔡正倫

中原大學/工學院/醫學工程研究所/碩士(2009年)

https://doi.org/10.6840/cycu200900337

摘要

本研究研製一植入型骨傳導式助聽器，其結構主要分為植入端與發射端。植入端的結構是由一個包覆於矽膠(PDMS)中的永久磁鐵構成，由發射端產生一時變電磁場，進而驅使植入端產生震波傳遞至乳突骨上。
植入端的設計主要以提升震動力量為主，所以加入磁粉芯外環後，可以使磁場更加聚集而增大震動力量，並且增加一層矽膠匹配層後，低頻的震動力量也可以增強。利用人工乳突骨來量測植入型骨傳導式助聽器震動力量，結果顯示最大值可以比顳骨刺激器增大約20.5dBμN。
研究中並使用多重物理量的有限元素模型來輔助助聽器設計，模擬結果顯示植入端磁鐵的尺寸與矽膠的厚度改變會影響助聽器的震動頻寬與力量。所以模擬改良後的設計，其震動力量最大值可以達到93.70dBμN 且震動頻率可以涵蓋20Hz至10KHz的範圍。

關鍵字

植入型骨傳導式助聽器 ； 有限元素法 ； 人工乳突骨 ； 多重物理量分析

並列摘要

This study is to develop a bone conduction hearing aid implant. The implanted vibrator is a permanent magnet embedded in polydimethylsiloxane (PDMS). An external actuator transcutaneously derives the vibrator using electromagnetic force.
The design of vibrator is to elevate the vibrating force delivered to mastoid bone. A ferric ring is used to constrict the magnetic field to increase the vibrating force. Then thin matching layer made by PDMS also improves the vibration at low frequency. By using the B&K 4930 artificial mastoid to evaluate its performance, the vibrator implant can generate a vibrating force about 20.5dBμN higher than that by an Audiant Bone Conductor.
The design of the hearing aid was assisted by a multiphysics finite element model. The simulation results show the influence of the size of magnet, ferric core, and the thickness of PDMS on the frequency response of vibrator. The simulation of an improved design shows the vibration force can be further elevated to 93.7dBμN. The hearing aid can also cover a frequency range from 20 Hz to 10 kHz.

並列關鍵字

bone conduction implant hearing aid ； Multiphysics system analysis ； finite element method ； B&K 4930 artificial mastoid

參考文獻

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