Acoustic Control System Using Boundary Vibration with Giant Magnetostrictive Actuator

(Comparative Consideration of Noise Reduction Volume by Changing Actuator Excitation Position)

Abstract

　In recent years, the spread of ultra-compact electric vehicles (EVs) is progressing rapidly. These vehicles have advanced characteristics such as compactness, light body, and low environmental impact. However, it is serious problem with interior noise which are road and wind noise from outside. Therefore, we have proposed an active noise control (ANC) system for ultra-compact EVs using boundary vibration by a giant magnetostrictive actuator. In this paper, we conducted two fundamental considerations about the vibration characteristics of the vehicle’s wall surface. In the first experiment, we investigated the output characteristics of the acoustic wave depending on the excitation position of the giant magnetostrictive actuator. In the second experiment, we carried out the experiment about the amount of in-vehicle noise reduction depending on the excitation position of the giant magnetostrictive actuator. As experimental results confirmed that installing the actuator at the excitation point where the sound wave output efficiency is high has a high noise reduction effect.