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This study deals with the experimental investigation of the mechanical properties of a lithium-ion pouch cell and its modelling in an explicit finite element simulation code. One can distinguish between ‘macroscopic’ and ‘microscopic’ modelling approaches. In the ‘macroscopic’ approach, one material model approximates the behaviour of multiple inner cell layers. In the ‘microscopic’ approach, which is used in the present study, all layers and their interactions are modelled separately. The cell under study is a pouch-type lithium-ion cell with a liquid electrolyte. With its cell chemistry, design, size and capacity it is usable for automotive applications and can be assembled into traction batteries. One cell sample was fully discharged and disassembled, and its components (anode, cathode, separator and pouch) were examined and measured by electron microscopy. Components were also tensile tested.

The objective of this work is to test the potential benefit of active pedestrian protection systems. The tests are based on real fatal accidents with passenger cars that were not equipped with active safety systems. Tests have been conducted in order to evaluate what the real benefit of the active safety system would be, and not to gain only a methodological prediction. The testing procedure was the first independent testing in the world which was based on real fatal pedestrian accidents. The aim of the tests is to evaluate the effectiveness of the Volvo pedestrian detection system. The in-depth accident database ZEDATU contains about 300 fatal pedestrian traffic accidents in urban areas. Eighteen cases of pedestrians hit by the front end of a passenger vehicle were extracted from this database. Cases covering an average traffic scenario have been reconstructed to obtain detailed model situations for testing.

The pole side impact test has been mandatory in Euro NCAP since 2009 and it includes, in addition to the head, assessments on other critical body regions that might be affected such as the chest, abdomen and pelvis. This paper describes a new test method for predicting Anthropomorphic Test Device responses to calculate injury index in side impact tests of a rigid pole under Euro NCAP conditions. Simplified sled tests are very effective in reducing the cost and time of development of more advanced side impact safety devices. To accomplish sled tests successfully, it is necessary to reconstruct accurately the combined dynamic deformation behavior of door and seat in pole impact. That behavior varies among different dummy response regions. Conventional sled test methods, published in previous literature, can reconstruct the deformation of the entire door using a single actuator at constant intrusion velocity but actual door velocity isn't constant in full scale vehicle crash tests.

Currently lithium-batteries are the most promising electrical-energy storage technology in fully-electric and hybrid vehicles. A crashworthy battery-design is among the numerous challenges development of electric-vehicles has to face. Besides of safe normal operation, the battery-design shall provide marginal threat to human health and environment in case of mechanical damage. Numerous mechanical abuse-tests were performed to identify load limits and the battery's response to damage. Cost-efficient testing is provided by taking into account that the battery-system's response to abuse might already be observed at a lower integration-level, not requiring testing of the entire pack. The most feasible tests and configurations were compiled and discussed. Adaptions of and additions to existing requirements and test-procedures as defined in standards are pointed out. Critical conditions that can occur during and after testing set new requirements to labs and test-rigs.

This research describes a different method of approach to evaluate the occupant kinematics and the acceleration pulse as well as injury criteria in different frontal impact scenarios. With the help of the stiffness based impact model of PC-Crash, input data for the multi body simulation code MADYMO was generated to evaluate occupant behavior in different vehicle-to-vehicle frontal impact scenarios. These results were compared and validated against a non linear finite element analysis (LS-Dyna) together with MADYMO to evaluate the accuracy of the PC-Crash/MADYMO analysis. The results show that the accuracy of the PC-Crash/MADYMO simulations are in close correlation to the LS-Dyna/MADYMO analysis in terms of vehicle acceleration pulse, post impact velocity, occupant acceleration as well as occupant kinematics, belt forces and injury criteria.

The aim of this study was to assess the feasibility of using a high speed x-ray system (capable of 1000 frames/sec) to evaluate the bony kinematics of post mortem human surrogate (PMHS) cervical spines at real world speeds during frontal impact. Whole body frontal impact sled tests were performed on two fresh PMHS specimens. Screws were inserted into the tips of the spinal processes to optimize contrast on the high speed cine x-ray. Head, T1 and sternum accelerations, as well as shoulder, and lap belt forces were recorded. Vertebral motion was captured using a modified mobile c arm x-ray system, and an image intensifier linked to a high speed camera (Kodak motion corder analyzer, model SR 1000C, Kodak, San Diego, CA, USA) The variable parameters for the tests were camera frame rate and sled velocity. Tests were performed with delta-V’s (Δv) of approximately 15 kph (8G) and 21 kph (10G). Cine x-rays of the tests were recorded at 250, 500 and 1000 frames/sec.

Structural component testing is essential for the development process to have an early knowledge of the real world behaviour of critical structural components in crash load cases. The objective of this work is to show the development for a self-sufficient structural component test bench, which can be used for different side impact crash load cases and can reflect the dynamic behaviour, which current approaches are not able. An existing basic system is used, which includes pneumatic cylinders with a controlled hydraulic brake and was developed for non-structural deformable applications only (mainly occupant assessments). The system is extended with a force-distance control. The method contains the analysis of a whole vehicle FEM simulation to develop a methodology for controlled force transmission with the pneumatic cylinders for a structural component test bench.

Due to the increasing number of minivans and sport utility vehicles, rollovers have become more significant. As a result, various accident reconstruction programs have been developed to address this issue. To reconstruct rollover crashes, various requirements have to be fulfilled. These consist of: providing a simple method that is able to model three dimensional environments that often play a major role in rollovers. including suspension, tire and collision models must be provided. This is particularily important in the rollover initiation phase. including proper vehicle geometry and contact stiffness must be available. These are important for simulation of body contacts that affect the vehicle motion. This study focuses on one program, PC-CRASH. This program was developed to allow simulations of vehicle 3-dimensional movements before, during and after the impact. The study also discusses the physical background of the models, their capabilities as well as their limitations.