School of Mechatronic Engineering, China University of Mining and Technology, Xuzhou 221116, China.
Department of Otorhinolaryngology Head and Neck Surgery, Beijing Tongren Hospital, Capital Medical University, Beijing 100730, China.
Math Biosci Eng. 2022 Jan 7;19(3):2453-2470. doi: 10.3934/mbe.2022113.
Round-window stimulating transducer is a new solution to treat mixed hearing loss. To uncover the factors affecting the round-window stimulation's performance, we investigated the influence of four main design parameters of round-window stimulating type electromagnetic transducer. Firstly, we constructed a human ear nonlinear lumped parameter model and confirmed its validity by comparing the stapes responses predicted by the model with the experimental data. Following this, an electromagnetic transducer's mechanical model, which simulates the floating mass transducer, was built and coupled to the human ear model; thereby, we established a nonlinear lumped parameter model of implanted human ear under round-window stimulation and verified its reliability. Finally, based on this model, the influences of the four main design parameters, i.e., the excitation voltage, the electromechanical coupling coefficient, the support stiffness, and the preload force, were analyzed. The results show that the change of excitation voltage does not alter the system's natural frequency. Chaotic motion occurs when the electromechanical coupling coefficient is small. Meanwhile, the stapes displacement appears to increase firstly and then decrease with the increase of the electromechanical coupling coefficient. The increase of the support stiffness enlarges the resonance frequency of the stapes displacement and reduces the stapes displacement near the resonance frequency, deteriorating the transducer's hearing compensation at low frequency. The preload force can improve the transducer's hearing compensation performance in mid-high frequency region.
圆窗刺激换能器是一种治疗混合性听力损失的新方法。为了揭示影响圆窗刺激性能的因素，我们研究了圆窗刺激式电磁换能器的四个主要设计参数的影响。首先，我们构建了一个人耳非线性集总参数模型，并通过将模型预测的镫骨响应与实验数据进行比较来验证其有效性。接下来，建立了模拟浮置质量换能器的电磁换能器机械模型，并将其与人体耳模型耦合，从而建立了圆窗刺激下植入人耳的非线性集总参数模型，并验证了其可靠性。最后，基于该模型，分析了四个主要设计参数，即激励电压、机电耦合系数、支撑刚度和预紧力的影响。结果表明，激励电压的变化不会改变系统的固有频率。当机电耦合系数较小时，会发生混沌运动。同时，随着机电耦合系数的增加，镫骨位移先增加后减小。支撑刚度的增加会增大镫骨位移的共振频率，并减小共振频率附近的镫骨位移，从而降低换能器在低频时的听力补偿性能。预紧力可以改善换能器在中高频区域的听力补偿性能。
