The development of an AVAS for enhancing the robustness of acoustic performance and reducing interior noise in a cabin

All the electric vehicles are required to provide warning sound by AVAS (Acoustic Vehicle Alert System) for the safety of pedestrians. AVAS sound should satisfy the regulations outside a vehicle while noise caused by the AVAS should be maintained below a level inside a cabin. Nowadays, it becomes difficult to fulfill these goals since various sensors for automotive drive are newly introduced in the space where the AVAS is traditionally located and an open area to emit sound is decreased to improve an electric efficiency of a car. Since the AVAS performance is very sensitive to a small change of the cavity, the increased complexity of the cavity makes it more challenging to develop a robust AVAS. The purpose of this study is to suggest a new AVAS for enhancing the robustness of acoustic performance as well as reducing interior noise in a cabin. Firstly, a series of simulations are carried out to closely investigate various design factors of the AVAS. Secondly, the improved performance of the new AVAS is shown through tests and simulations. Thirdly, a method to decide the optimal speaker location is newly suggested by simultaneously considering crucial performance factors obtained from multiple vehicle level simulations.