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Expanding various future mobilities such as purpose built vehicle (PBV), urban air mobility (UAM), and robo-taxi, the application of autonomous driving system (ADS) technology is also spreading. The main point of ADS is to ensure safety by monitoring vehicle anomalies to prevent functional failure or accident. In this study, a model-based diagnosis and prognosis process was established using degradation data generated during autonomous driving simulation. A vehicle model was designed using Modelica/Dymola, and autonomous driving simulation was performed by integrating the lane keeping assistant (LKA) system with the vehicle model using Matlab/Simulink. Degradation data for the 3 components (a shock absorber damper, a suspension bush, and a tire) of the chassis system were input into the integrated simulation model. The degradation behavior was monitored with K-nearest neighbor (K-NN) and Gaussian mixture model (GMM).

This study presents a design methodology to predict the crash behavior of mid-size sedan with a simplified crash model. Without detailed conventional finite element, the simplified crash model can be adopted in the early stage of the vehicle design. Designing vehicle structure to satisfy crash performance target is highly complex problem in the early design stage, because of the nonlinear mechanical behavior, high number of degrees-of-freedom, lack of information and boundary conditions changing over the following development process. In this study, the front structure of the vehicle is divided into load-carrying members and the rigid element through the analysis of load-carrying mechanism, and its physical property (force-displacement relation) is parameterized as the property of the non-linear discrete beam element of the LS-DYNA. The effectiveness of the proposed research is shown by the example of the mid-size sedan.

Every year several thousands of unprotected road users are killed in car accidents. The European Commission is working on new regulations to improve passive pedestrian protection on passenger cars significantly. Recently, European Parliament has made the decision to support the commitment on pedestrian safety proposed by the European Automobile Manufactures Association. Therefore, pedestrian protection measures will be required on all passenger cars sold in Europe from 2005. In this study, to improve levels of current performance, some modifications on current production vehicle have been made including the bumper, hood hinge, fender, etc. The lower legform and child headform impact tests were carried out on current production vehicle and new prototype. The solution for lower leg protection was achieved through a combination of design factors.

The European Commission is proposing legislation aimed at enabling a pedestrian to survive a frontal impact without serious injury or death with a vehicle travelling at 40 km/h. One aspect of this proposed legislation is reducing the pedestrian's leg injuries due to contact with the bumper and frontal surfaces of a vehicle, assessed using a legform. In this study, the finite element model for legform impactor was developed to investigate the effects of various design parameters on pedestrian lower leg impact. The model is first matched with the result of component test, then matched with the result of the test on actual vehicle. Using this model, the optimization design of bumper structure for lower leg impact was performed. The statistical design support system (SDSS) was applied for the optimization, where the acceleration, bend angle and shear displacement of legform impactor were chosen as the objective functions, and the simultaneous optimization for the functions was carried out.

This paper presents results of an analytical simulation to evaluate the crashworthiness of the car in a frontal offset impact into the fixed deformable barrier. A finite element model for a 4 Wheel Drive vehicle frontal offset impact has been developed including engine, engine mounts, tire, steering column, propeller shaft, etc. A frontal impact with 40% offset has been simulated at 40mph using the nonlinear explicit finite element code of PAM-CRASH. A relatively well correlated finite element model concerning the deformation and deceleration of the vehicle has been achieved, and the feasible methodology for model improvement has been discussed.