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This study is a systematic investigation of the body mounts' dynamic characteristics in component, sub-system and full system levels and its application in the frontal impact analysis of a body-on-frame (BOF) vehicle. Concluded from the component study, the body mount is modeled by non-linear spring with built-in damage and rupture properties. The sub-system study reveals the importance of modeling the interaction between the body mount and its surrounding structure. A general-purpose interaction modeling is developed to provide a realistic CAE simulation of this interaction behavior. The full system is mainly for methodology validation. Four 90-degree frontal and the one IIHS offset frontal crash tests are used to evaluate the performance of the body mount in low and high speeds and its capability of predicting the body mount and the floor pan failures.

Spot-welds are the primary joining methods for steel sheet metals used in the manufacturing of automobile body structure. Often the impact responses are significantly affected by the characteristic properties, such as stiffness, failure strength, etc of spot-welds. In view of this, understanding the behavior and the properties of spot-welds under static and impact loadings are critical for accurate CAE analysis of vehicle impact events. To this end, a comprehensive DOE based spot-weld testing has been undertaken by considering a wide variety of variables. The test data thus obtained were analyzed to determine the requisite mechanical properties of spot-welds as a function of the key variables such as gage, yield strengths, speed, etc. Spot-weld connections have been tested for gages ranging from 0.7 to 3.0 mm using a unique specimen configuration developed at Ford.

This study summarizes the latest development of the methodologies for testing and CAE modeling of the engine mount. A systematic approach is used in this study with detailed component, subsystem and full system level investigations. The component level study reveals the entangling phenomenon of the inertial and rate effects in the engine mount dynamic characteristics. In the subsystem, the interaction between the engine mount and its surrounding structure is explored. The full system study is primarily used to validate the CAE methodology for engine mounts developed in the component and subsystem level studies. Four full vehicle barrier crash tests, with different crash modes and speeds, are employed in this validation phase to evaluate the performance of the engine mount CAE methodology.

The objective of this study is to verify the performance of a target vehicle model in vehicle-to-vehicle impact applications. In some vehicle-to-vehicle tests, the target vehicle stays the same and the bullet vehicle changes from test to test depending on the programs under evaluation. To obtain reasonable crash pulse predictions in vehicle-to-vehicle impacts, it was decided to develop an accurate and robust target vehicle model first. The development of the target vehicle model was divided into two phases, rigid barrier and vehicle-to-vehicle impacts. Twelve rigid barrier tests, including full rigid barriers, angular rigid barriers, offset rigid barriers, and fixed rigid poles were adopted in the first phase of the study to calibrate the target vehicle model. The results of the study have been reported [1]. This paper focuses on the verification of vehicle-to-vehicle impacts.

The objective of this study is to develop a target vehicle model for vehicle-to-vehicle impact applications. In order to provide reasonable predictions for crash pulses in vehicle-to-vehicle impacts, an accurate and robust target vehicle model was developed first. An ideal target vehicle model should be able to provide reasonable results when hit by different bullet vehicles at different impact speeds and under different impact conditions. This was achieved by calibrating the target vehicle model against different vehicle crash tests, which include full rigid barriers, angular rigid barriers, offset rigid barriers, and fixed rigid poles. Twelve rigid barrier tests were adopted in this study to calibrate the target vehicle model. During the calibration process, some of the vehicle structures were examined and remodeled carefully for their properties and mesh quality.

This paper reports the latest development of methodologies for testing and CAE modeling of the automobile mounts. The objective of this study is to provide dynamic mount properties for product evaluation and CAE modeling guideline for crashworthiness simulations. The methodology is divided into component, subsystem and full system levels. The study at the component level is to extract the dynamic parameters of mounts, such as stiffness and damping coefficient, based on the component tests. Furthermore, such parameters are employed to investigate the interaction between mount and connecting structures at the subsystem level. A robust connection mechanism from mount to surrounding structures is also developed during this process. Finally, the results from full vehicle system tests are compared with the CAE simulations to verify the methodology at the component and subsystem levels. A robust component test methodology is the first key element of this study.

An accurate and robust target vehicle model was developed for vehicle compatibility applications. Although vehicle compatibility simulation involves a bullet vehicle hitting a target vehicle, the focus of this paper is to develop a target vehicle model. To ensure the robustness, the target vehicle model needs to provide reasonable responses under different impact conditions. This can be achieved by calibrating the model against different physical tests. Significant effort was taken to improve the accuracy of the target vehicle model. In the calibration process, some components were found to have significant effects on the global responses. These components play different roles in different crash modes. To improve the overall correlation with test, different component tests were also designed and conducted to understand the characteristics and improve the modeling of these critical components.

Statistic shows the majority of real world frontal collisions involve only partial overlap of the vehicle front end. Thus the European Experimental Vehicle Committee (EEVC) has established a safety standard and test procedure utilizing a deformable barrier for offset impacts. The offset deformable barrier (ODB) is designed to represent the characteristics of a vehicle front end. Therefore, it can replace a target vehicle and the offset test can be conducted economically. Many component, sub-assembly and full vehicle system tests have been conducted in Ford using the EEVC ODB. Based on the various tests, the barrier responds differently depending on the front end design and the size of an impacting vehicle. Sometimes the front end of a test vehicle punches through the barrier. Also rupture of aluminum sheets and tearing of honeycomb materials are often observed in post-test barriers.