Designing the Actuator of Hearing Aid Using Spiral Coils and Finite Element Analysis

ObjectiveAn electromagnetic vibration transducer was developed to be used as a hearing aid.Materials and MethodsThis type of electromagnetic transducer should have the following characteristics: small in size, high-energy efficiency and suitable frequency bandwidth. In order to find the output of electromagnetic force and to predict the frequency-amplitude characteristics, a finite element middle ear biomechanical model was used to derive the optimal magnetic force of the actuator in this study. First, the electromagnetic transducer was created using a computer-aided design. The air gap between the magnet and coil, input current and vibration force were calculated using finite element analysis simulation.ResultsSimulated results showed that electromagnetic forces under 1.0 mm air gap was about 5–25 dyne depending on the turns of coils and input current of the actuator.ConclusionThe designed actuator could be used as transducers for middle ear implants or bone anchors in hearing aids.