Impact of Preload and Amplitude on the High-Frequency Behaviour of Rubber Bushings in Electric Vehicles: An Experimental Study

<div class="section abstract"><div class="htmlview paragraph">Electric vehicles (EVs) are particularly susceptible to high-frequency noise, with rubber eigenmodes significantly influencing these noise characteristics. Unlike internal combustion engine (ICE) vehicles, EVs experience pronounced variations in dynamic preload during torque rise, which are substantially higher. This dynamic preload variation can markedly impact the high-frequency behaviour of preloaded rubber bushings in their installed state.</div><div class="htmlview paragraph">This study investigates the effects of preload and amplitude on the high-frequency dynamic performance of rubber bushings specifically designed for EV applications. These bushings are crucial for vibration isolation and noise reduction, with their role in noise, vibration, and harshness (NVH) management being more critical in EVs due to the absence of traditional engine noise. The experimental investigation examines how preload and excitation amplitude variations influence the dynamic stiffness, damping properties, and overall performance of rubber bushings under high-frequency excitation.</div><div class="htmlview paragraph">The research methodology involves subjecting rubber bushings to various preload conditions and excitation amplitudes across relevant high-frequency domains. The findings reveal significant dependencies of dynamic characteristics on preload and amplitude, identifying critical thresholds where performance is notably affected. These insights are pivotal for optimizing rubber bushings in EVs, contributing to improved ride quality, enhanced NVH performance, and increased vehicle durability.</div></div>