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A comparison between a hydraulic engine mount and a mixed mode magnetorheological (MR) fluid engine mount is presented. MR fluid is a smart material that changes viscosity in the presence of a magnetic field. In other words, without the presence of a magnetic field, the fluid is classified as a Newtonian fluid, however; with the presence of a magnetic field, the fluid becomes classified as a Bingham plastic. The working modes of the MR mount are squeeze and flow. Hydraulic mounts were developed to address the conflicting requirements of the engine vibration profile. The engine vibration profile can be classified as large displacement in the low frequency range and small displacement in the high frequency range. The hydraulic mount used in this study is an as received OEM mount. The elastomeric top and bottom of the hydraulic mount were used to create the MR mount. In the paper, the advantages and disadvantages of each mount are discussed in detail.

The chassis are subject to both road profile and engine or pump/motor vibration when a vehicle is moving on the road. The suspension is developed to reduce the effect of the road conditions to the chassis. The vibration from engine or pump/motor of hydraulic hybrid vehicles (HHV) will be also transmitted to the chassis and needs to be isolated. A mixed mode magnetorheological (MR) fluid mount is presented to isolate force vibration for a two degree of freedom (DOF) model based on quarter car concept. The MR fluid mount is designed to work in flow mode and squeeze mode separately and simultaneously. The skyhook control for the MR fluid mount is also been designed and simulated. Both displacement transmissibility and force transmissibility for each mode and for combined modes have been obtained. These simulation results present a basis for designing a more effective controller to control both the displacement transmissibility and force transmissibility.

High frequency responses of structural-acoustic systems may be predicted by statistical energy analysis (SEA) or energy finite element method (EFEM). To combine the good features of these two techniques, a simplified energy finite element method, referred to as EFEM0, has been developed recently. The EFEM0 technique, which is compatible with SEA, integrates the joint coupling procedures for discontinuous systems and the finite volume formulation for continuous system. The EFEM0 models have been verified either analytically or experimentally for one- and multi-dimensional systems. In this study, the EFEM0 technique is applied to a passenger van for a noise control investigation. The general scheme is to incorporate the EFEM0 coupling factors into a SEA model in order to release some SEA assumptions and improve the SEA model, especially for relatively high damping, strong coupling and direct field cases.

Perforating certain layers of laminated material can improve the sound absorption performance of the material. The hole size, shape, angle, spacing and pattern can be tuned to improve sound absorption in a certain frequency range using a validated acoustical model. The model is based on a numerical calculation of acoustical properties of porous multi-layers using a transfer matrix method in the context of the Biot theory in NOVA software. An additional calculation of airflow resistivity and porosity from the hole size and hole spacing is also conducted. The model predictions agree with the testing data. Based on this model, the acoustical performance of the material can be optimized to meet vehicle acoustical requirements. The vehicle level SEA models are used to examine the effects of the perforation on the vehicle interior acoustics.

Good braking performance is an important guarantee for the vehicle driving. In the condition of frequent or prolonged braking, the overheating problem for the traditional mechanical braking device causes the recession of the braking performance, which is a prominent problem especially for the commercial vehicle perennial traveling in the mountains. Eddy current retarder can reduce the mechanical brake load as a kind of auxiliary braking device. Thus, the temperature of the mechanical braking device would not be too high, and the traveling safety of the vehicle can be ensured. But eddy current retarder would cause an enormous impact for automobile battery when it starts up and huge electricity energy would be consumed which means that more automotive batteries are needed. Considering above, a kind of self-excited eddy current retarder is developed in the paper.

The energy finite element method (EFEM) was developed to utilize available finite element geometric models for high frequency structural-acoustic analysis. Statistical Energy Analysis (SEA) is a lumped parameter approach currently in widespread use for high frequency analysis. In this investigation, EFEM and SEA models were developed for components of a heavy equipment cab. A generalized joint process (GJP) was developed and used for processing the various joints between structural subsystems. The structural predictions were compared to each other as well as to measurements.

Hardware-in-the-loop (HIL) testing is part of automotive V-design which is commonly used in automotive industries for the development of Electronic Control Unit (ECU). HIL test platform provides the capacity to test the ECU in a controlled environment even with scenarios that would be too dangerous or impractical to test on real situation, also the ECU can be tested even before the actual plant under building. This paper presents a HIL test platform for the validation of a seat ECU. The HIL platform can also be used for control and diagnostics algorithm development. The HIL test platform consists of three parts: a real time target machine (dSPACE SCALEXIO AutoBox), an ECU (Magna Seating M12 Module), and a signal conditioning unit (Load Box). The ECU produces the control commands to the real-time target machine through load box. The real time target machine hosts the plant model of the power seat which includes the kinematics and dynamics of the seat movements.