Automotive Vehicle Engine Mounting Systems: A Survey

Abstract

This study divided into three portions to provide performance requirements; overview and development of various engine mounts; and the optimization of engine mount systems. The first part provides an insight about the ideal engine mount system that should isolate vibration caused by engine disturbance force in various speed range and prevent engine bounce from shock excitation. This implies that the dynamic stiffness and damping of the engine mount should be frequency and amplitude dependent. Therefore, the development of engine mounting systems has mostly concentrated on improvement of frequency and amplitude dependent properties. The second part starts discussion on the conventional elastomeric mounts that offer a trade-off between static deflection and vibration isolation. The next level, passive hydraulic mounts can provide a better performance than elastomeric mounts especially in the low frequency range. Subsequently, semi-active and active techniques are used to improve performance of hydraulic mounts by making them more tunable. The active engine mounting system can be very stiff at low frequency and be tuned to be very soft at the higher frequency range to isolate the vibration. The final part is about the optimization of engine mounting systems. An overview of the current work on this optimization shows some limitations. Further study is needed to consider the nonlinearities and variations in properties of different types of mounting systems.

Antagonistic variable stiffness elements

“…Controlling the bouncing of the engine from low frequency shock excitations (0-20 Hz) caused by sudden acceleration and braking and riding on bumpy roads; 2. Isolating the chassis from the high frequency Hz) engine excitations caused by the firing pulse and rotating parts inside the engine [34].…”

Design optimization of machinery mounting systems with an elastic support structure

“…The use of optimization techniques in the design of mounting systems for a wide range of industrial machinery has attracted increasing attention in recent years because of the ability of these techniques to minimize vibration transmission from the machines to their support structures (Ashrafliuon 1993, Swanson et al 1993, Snyman et al 1995, Tao et al 2000, Yu et al 2001, Ahn et al 2003, Alkhatiba et al 2004, Kaul et al 2005. Specifically, an optimal *Corresponding author.…”

Shape optimization of rubber isolators in automotive cooling modules for the maximization of vibration isolation and fatigue life

“…The optimization algorithm is the modified feasible direction (MFD) in DOT. Yu et al (2001) reported survey papers regarding the performance requirements for engine mounting systems and summarized the development of various engine mounts and the optimization of engine-mounting systems. Suh et al (2003) optimized an engine system using multidisciplinary design optimization to improve the idle refinement of the vehicle and remove the possibility of interactions between the powertrain system and vehicle systems; sequential quadratic programming was used as the optimization algorithm.…”