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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).

The vehicle elastomeric components such as engine mounts could be aged and degraded by environmental loads such as thermal and mechanical loads during long term usage by customers. These make the degradation of vehicle driving performance comparing with a new condition. In this study, the main cause of NVH (Noise, Vibration and Harshness) degradation of a used vehicle was analyzed. It could be identified by the analysis of vibration insulating property changes of elastomeric components. The properties changes of aged engine mounts were analyzed and compared with initial properties. The accelerated laboratory ageing test mode was developed for simulating the degradation of engine mounts by thermal load analysis. Moreover, parametric studies were carried out to identify the robust engineering design technique. The engineering design parameters of elastomers such as volume, thickness and mechanical loading types were identified to improve the degradation phenomenon.

Recently, many kinds of new technology systems are adapted to a new developing vehicle. However the field usage information of a new technology system could not be easily obtained because it has not been used by customers. It is not easy to evaluate the reliability and durability of this system. In this research, the durability test mode of a new Adaptive Front Lighting System (AFLS) with Light Emitting Diodes (LEDs) as a new light source has been developed for a new large luxury sedan vehicle. First of all, the failure mode effect was analyzed by considering failure mechanism for each component. The thermal, vibrational, operational and electrical loads were investigated. The Road Load Data Acquisition (RLDA) technique was used to collect the vibration and temperature of an AFLS in a proving ground. The vibration test mode was designed by a Power Spectral Density (PSD) approach. The customer usage data was used for making the target cycles of operational movement such as swiveling.

This study examined various warranty data analysis methods to identify and study the one most suitable for Hyundai Motor warranty data. The drawbacks of the conventional life table method were overcome to develop an analysis method optimized for vehicle characteristics. The proposed method was examined for its suitability to various applications, such as providing the information necessary for determining the service life of parts, verifying the effects of design changes, and designing warranty and maintenance policies. The analysis data used in this study were derived from the 10-year powertrain parts warranty data of vehicles sold in the USA, South Korea, and China.

As a new vehicle is based on common vehicle platform, the durability problems of chassis components in development stage are decreasing. However a vehicle body structure is changed by exterior design and a chassis and a suspension are tuned by vehicle performance targets. The main issue on developing a new vehicle is to satisfy the durability target of a body structure and tuned suspension components. The accuracy of durability Computer Aided Engineering analysis is mainly depending on the accuracy of input loads and boundary conditions on suspension system. The input loads should be estimated accurately. These could be changed by vehicle specifications such as vehicle weight, wheel base and so on. It is also affected by the change of suspension types and tuning parameters. This paper presents the experimental parametric study results using road load data analysis techniques.

The recent improvement in CAE and testing technologies of vehicle structures could reduce the development time of new vehicle chassis platform. Moreover, it is important to validate the durability of a new chassis platform before making new prototypes. However, it is difficult to satisfy durability target for this new platform before the prototype phase. The optimized durability test modes of suspension components under the multi-axial road load could help to evaluate durability on the early phase of vehicle development. In this study, the RLDA (Road Load Data Acquisition) and DFSS (Design for Six Sigma) techniques are used to identify the principal loading from the applied multi-axial load on suspension components. This paper presents more efficient way for the determination of durability target of suspension components. Further more, the verification are described by comparing the results of component tests with that of a rig full vehicle durability test.

The recent improvement in CAE technology of vehicle structure could reduce the new vehicle development time. Moreover, it can help to reduce the test time of prototypes. The finite element analysis (FEA) has been proved for long time by many experiments in developing a new vehicle. However, the FEA has been applied mainly on metal structures such as steel and aluminum. The fatigue analysis could not successfully apply on the rubber insulator or bushing until now. Moreover, the more difficult thing is the identification of the applied loads on rubber bushings in all kinds of control arms. In this paper, the virtual testing laboratory (VTL) technology and load measuring techniques are integrated for identifying dynamic loads and torsional deformation of suspension bushings in a proving ground (PG). This paper presents the efficient rig-test of suspension bushings as the applied loading patterns.

With the advent of cars with computerized engines, drivers sometimes suffer discomfort with “check engine” light problem, and as a result, insist on increasing levels of reliability in their cars. Hence, reliability of the wiring harness has become a very important automotive design characteristic. On one hand, the more secure an engine mounting system is, the more stable the engine wiring harness is. In order to enhance their durability, car manufacturers need to perform many validation tests during the development phase which involves a lot of time and cost. In this study, a newly developed lab-simulation test is proposed to qualify the design of engine mounting and engine wiring early in the design cycle and reduce time and expense. The lab-simulation test has contributed to a significant cost and time reduction and has shown good correlation to the original proving ground test.