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.

Occupant safety and severity of vehicle damage are important factors in automotive vehicle design. Smart automobiles of the future could potentially use distributed smart material sensors and actuators in order to identify impact and take appropriate evasive or mitigative actions. This provides the motivation for this study. The first part of this study is focused on detecting the location and magnitude of impact, particularly for the case where the automotive structure is subjected to minimal damage. This is accomplished by developing a generalized algorithm using the Reissner–Mindlin plate theory, the Rayleigh–Ritz energy approach, and the Lagrangian–Hamilton principle. The level of performance of this methodology is demonstrated for impacts on a simply supported rectangular plate. Different case studies for static as well as impact loading with point as well as area contacts are presented. An algorithm using deconvolution for identifying impact location and magnitude has been developed and implemented. Additionally, the influence of damage on the structural vibratory content is studied via a frequency analysis. Modal analyses for undamaged and damaged plates, with nine different damage locations and six different damage sizes, are performed. Changes in frequency and mode shapes are observed as regards the severity of the damage.

In the design of automobiles, occupant safety during a crash is an important factor to consider. The vehicle should identify impact, handle passenger safety through the deployment of various safety restraint systems, and steer the vehicle away from impact. With this background, this work is to find the impact location, magnitude, and identify damage on a metallic structure. The first phase through the use of experiment and finite element analysis is to demonstrate the effectiveness of a piezoceramic sensor and its ability to handle different orientations. In the second phase, the dynamic plate equation for impact is developed using the Mindlin plate model, Ritz energy approach, and Hamilton principle. In the third phase, different forward model case studies of static and dynamic situations are compared with the FEM and theoretical work. The final phase is to find frequency of undamaged and damaged plate area of 0.1% and 1% for various locations, to help in assessing the amount of damage.

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Occupant safety and severity of vehicle damage are important factors in automotive vehicle design. Smart automobiles of the future could potentially use distributed smart material sensors and actuators in order to identify impact and take appropriate evasive or mitigative actions. This provides the motivation for this study.The first part of this study is focused on detecting the location and magnitude of impact, particularly for the case where the automotive structure is subjected to minimal damage. This is accomplished by developing a generalized algorithm using the Reissner-Mindlin plate theory, the Rayleigh-Ritz energy approach, and the Lagrangian-Hamilton principle. The level of performance of this methodology is demonstrated for impacts on a simply supported rectangular plate. Different case studies for static as well as impact loading with point as well as area contacts are presented. An algorithm using deconvolution for identifying impact location and magnitude has been developed and implemented. Additionally, the influence of damage on the structural vibratory content is studied via a frequency analysis. The modal analysis for undamaged and damaged plates, with nine different damage locations and six different damage sizes are performed. Changes in frequency and mode shapes are observed in regard to the severity of the damage.