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When designing new vehicles, the legal requirements of the countries in which the vehicles are homologated must be observed and implemented. The manufacturers try to consider the legal framework of the UN-ECE (United Nations Economic Commission for Europe), CCC (China Compulsory Certification) and FMVSS (Federal Motor Vehicle Safety Standard) 108 in the same vehicle to keep the variance low. For the appearance of the vehicle, the position of the light modules in the front of the vehicle is important. In addition to the surface requirements of lighting functions, the positions of the low beam (LB), high beam (HB) and the position of daytime running lights (DRL) are also regulated. When it comes to these mounting positions, the legislation between the US and the EU differs quite significantly.

In order to correctly predict the impact of tire dimensions and properties on ride comfort in the early phases of the vehicle development process, it is necessary to fully understand their influence on the dynamic tire behavior. The currently existing models for reproducing tire forces often need many measurements for parametrization, simplify physical properties by empiric functions, or have an insufficient simulation speed to analyze many variants in the short periods of early process phases. In the following analysis, a tire concept model is presented, which utilizes relations between the static and dynamic behavior of tires in order to efficiently predict the dynamic forces in the vertical and longitudinal direction during obstacle crossing. The model allows for efficient parametrization by minimizing the number of parameters as well as measurements and ensures a high simulation speed. To realize this, initially, a selection of tires is measured on a tire test rig.

In order to predict reality as accurately as possible leads to the fact that numerical models in automotive vibroacoustic problems become increasingly high dimensional. This makes applications with a large number of model evaluations, e.g. optimization tasks or uncertainty quantification hard to solve, as they become computationally very expensive. Engineers are thus faced with the challenge of making decisions based on a limited number of model evaluations, which increases the need for data-efficient methods and reduced order models. In this contribution, variational autoencoders (VAEs) are used to reduce the dimensionality of the vibroacoustic model of a vehicle body and to find a low-dimensional latent representation of the system.

This paper covers research findings on digital projections on the road. Data is provided for the root cause analysis of non-existing distraction proven by several studies. The study describes if and in which geometrical space road projections are visible to other road traffic participants. Such participants can be e.g. oncoming, passing drivers or pedestrians standing aside the road. The paper data shows where projections are recognizable and assignable to the original intention of the projection. A grid was created to identify the areas where digital projections could be understood and where the digital projections were just illegible. A dominant factor is the grazing incidence. The photons are distributed over a larger area and only the driver’s view makes a virtual compression of the illuminated area in order to make the signals legible. The results show that distraction for other road participants is unlikely for any position outside very limited areas.

The current automotive electronic and electrical (EE) architecture has reached a scalability limit and in order to adapt to the new and upcoming requirements, novel automotive EE architectures are currently being investigated to support: a) an Ethernet backbone, b) consolidation of hardware capabilities leading to a centralized architecture from an existing distributed architecture, c) optimization of wiring to reduce cost, and d) adaptation of service-oriented software architectures. These requirements lead to the development of Zonal EE architectures as a possible solution that require appropriate adaptation of used security mechanisms and the corresponding utilized hardware trust anchors. 1 The current architecture approaches (ECU internal and in-vehicle networking) are being pushed to their limits, simultaneously, the current embedded security solutions also seem to reveal their limitations due to an increase in connectivity.

The current development of automotive lighting strives towards more and more lighting installations on vehicles. Additionally, to that, manufacturers start animating these lighting installations as coming home or leaving home greetings from the car to the driver. In a previous paper we have shown, that these additional animations are in fact not distracting to other road users and when used correctly, e.g. in a sequential turn indicator, can be beneficial to the overall traffic safety. This study then aims to investigate the potential influence of illuminated logos on road safety. European lawmakers forbid the use of illuminated advertisements on vehicles to minimize the danger of distraction for other road users and thereby negatively influencing traffic safety. As of now, active illumination of the manufacturer’s logo is considered an advertisement.

1. The present work introduces an approach for the analysis of the noise propagation behavior of mechatronic brake systems in modern passenger vehicles. While on the one hand, the number of features realized through the mechatronic brake system is strongly increasing; on the other hand, a continuous reduction of the overall vehicle interior noise level can be observed. This leads to an increase of interfering noise phenomena in the vehicle interior that customers might perceive as insufficient product quality. Therefore, noise elimination always plays an important role in vehicle development. The mechatronic brake system induces interfering noise that is transferred into the vehicle interior, differing from vehicle to vehicle and maneuver to maneuver. Supposedly, a wide frequency range, numerous components, and various branched transfer paths in the physical domains of airborne, structure-borne, and fluid-borne sound are involved in the noise propagation.

In this paper, the human intra- and interpersonal adjustment accuracy (or aiming) of headlamp cutoff lines with different methods are examined. Intrapersonal aiming accuracy is the repeatability of a single person, while interpersonal aiming accuracy describes the differences between different people. For this purpose, a study is developed, implemented and evaluated. In one experiment, the subjects set up three different headlamps using three different methods according to the ECE regulation. In addition, the three adjustment methods used are compared with each other and evaluated in terms of the variation resulting aim. The most common aiming method, the visual adjustment of the cutoff line, such as the 10-meter wall method or analog headlamp aiming devices shows the highest variations. It is shown that digital headlamp aiming devices generally also have a lower dispersion variance, while still being better than all other adjustment methods.

Two research fields are presented in this paper covering new lighting functions. In the first part, a study is presented that evaluates distraction by light animations. 41 test subjects were involved, and a situation was constructed with several traffic participants and an animated-light vehicle parked so as to be conspicuously within the test subjects’ view. 91% of the test subjects stated they felt little or no distraction or impairment from the light display on the parked car. 29% noticed something conspicuous about the test vehicle. 22% indicated they had noticed the car’s lights flashing as its central locking system was operating. Only 7%—three of the 41 participants—noticed the animations in addition to their traffic monitoring. Of these, two said they didn’t feel disturbed at all by the animations while the third found it only very slightly distracting. Nobody said the distraction or impairment was “neutral”, “little bit” or “strong”.

This paper explains why software for efficient model-based development is needed to improve the efficiency of automakers and suppliers when implementing solutions with next generation automotive embedded systems. The resulting synergies are an important contribution for the automotive industry to develop safer, smarter, and more eco-friendly cars. To achieve this, it requires implementations of algorithms for machine learning, deep learning and model predictive control within embedded environments. The algorithms’ performance requirements often exceed the capabilities of traditional embedded systems with a homogeneous multicore architecture and, therefore, additional computing resources are introduced. The resulting embedded systems with heterogeneous computing architectures enable a next level of safe and secure real-time performance for innovative use cases in automotive applications such as domain controllers, e-mobility, and advanced driver assistance systems (ADAS).

E-mobility is a game changer for the automotive domain. It promises significant reduction in terms of complexity and in terms of local emissions. With falling prices and recent technological advances, the second generation of electric vehicles (EVs) that is now in production makes electromobility an affordable and viable option for more and more transport mission (people, freight). Current e-vehicle platforms still present architectural similarities with respect to combustion engine vehicle (e.g., centralized motor). Target of the European project EVC1000 is to introduce corner solutions with in-wheel motors supported by electrified chassis components (brake-by-wire, active suspension) and advanced control strategies for full potential exploitation. Especially, it is expected that this solution will provide more architectural freedom toward “design-for-purpose” vehicles built for dedicated usage models, further providing higher performances.

Brake particle emissions as a part of non-exhaust emissions are becoming more and more relevant, various international research activities can be stated. Also from the legislation side, first hints are given in regards of possible regulations. One possible approach for the reduction of brake particle emissions deals with the collection of those particles close to the foundation brake. The presented paper will follow such an approach and give some insights. In a first step, the technical layout is described for bench and vehicle testing. While for bench testing a PMP-like style of the setup could be chosen, the vehicle test setup is oriented on conventional wheel dust measurements. Hence, presented results of laboratory testing are dealing with PN and PM measurements. Also the impact on particle size distribution is discussed. It can be stated, that the particle collecting system is able to improve PN and PM emissions. Additionally, ultra-fine particles are almost eliminated.

The statistical energy analysis (SEA) is widely used to support the development of the sound package of cars. This paper will present the preparation of a model designed to investigate the sound package of the new Audi A3 and associated correlation against measurements. Special care was given during the creation of the model on the representation of the structure to enable the analysis of structure borne energy flow on top of the classical airborne analysis usually done with SEA. The sound package was also detailed in the model to allow further optimization and analysis of its performance. Two real life load cases will be presented to validate the model with measurements. First, the dominating powertrain and a second load case with dominating rolling noise. An analysis of the contribution of the different source components and a way to diagnose the weak paths of the vehicle will be presented. The focus of this investigation is the application of optimally adjusted treatment.

Good lighting is crucial for safe driving at night. Unfortunately, many parameters are contributing to the final result of the individual tolerances of car body, dynamics and headlamp: the resulting aim. The paper will analyze individual tolerance contributors from car body parameters like load, tire pressure, suspension as well as temperature parameters of chassis and plastic parts. The investigation shows that the headlight aim can fluctuate in a worst case scenario more than ±0.3°.

The paper will describe actual investigations on safety improvements by new lighting functions. Especially the new chance of projections on the road surface either by simple reflector technology or by modern signature and pattern projection will be investigated. Different prototype patterns will be checked by a set of new parameters, e.g. reaction time to signals, clear understanding, minimum and optimum visual contrasts. The results show that high contrasts and dynamic effects are most effective.

New human-machine interfaces are the direct result of digitalization. So also in lighting, new constellations have to be taken into account when looking to the possibilities of giving additional informations to the driver. Lighting and furthermore information given by light is a clear preference during nighttime driving. The global interest in standardization of light driven messages from autonomous vehicles to other traffic participants has opened new research needs in order to prepare full view on such new human-machine interface. In Europe, GTB (Group de Travail de Bruxelles) has established a working group dedicated to this topic. In order to provide a complete picture of the effects of digital light, the question of additional glare contribution by digital informations, i.e. extra projected light in form of patterns, symbols or areas was addressed in this research study. This article will show the investigations on wet and dry road glare while driving with digital informations.

To assure high comfort for vehicle passengers, the interior noise has to be designed to be low in volume as well as in a pleasant way. Vehicle’s HVAC (heating, ventilation and air-conditioning) noise becomes increasingly audible when the main sound sources are acoustically optimized. Thus, the Sound Quality of HVAC noise needs to be evaluated early in the development process. For assessing the Sound Quality of HVAC noise, suitable evaluation criteria as well as the knowledge of the acoustics of the new HVAC system are required. Suitable evaluation criteria were identified using listening tests. In a second step HVAC noise was investigated in different environments: HVAC as a component, HVAC as a system (including air ducts and vents) and HVAC system integrated in a simplified car model. The model was designed acoustically similar to a series vehicle. Thus, the size as well as the interior paneling of a series vehicle was approximated by using sound-absorbing and -reflecting material.

The analysis of the acoustic behavior of flow fields has gained importance in recent years, especially in the automotive industry. The comfort of the driver is heavily influenced by the noise levels and characteristics, especially during long distance drives. Simulation tools can help to analyze the acoustic properties of a car at an early stage of the development process. This work focuses on the low-frequency sound effects, which can be a significant noise component under certain operating conditions. As a first step in the fluid-structure interaction workflow, the flow around a series-production vehicle is simulated, including passenger cabin and underhood flow. The complexity of this model poses extensive demands on the simulation software, concerning meshing, turbulence modeling and level of parallelism. We conducted a transient simulation of the compressible fluid flow, using a hybrid RANS/LES approach.

The acoustic trim components play an essential role in NVH behavior by reducing both the structure borne and airborne noise transmission while participating to the absorption inside the car. Over the past years, the interest for numerical solutions to predict the noise transmission through trim packages has grown, leading to the development of dedicated CAE tools. The incrementally restrictive weight and space constraints force today CAE engineers to seek for optimized trim package solution. This paper presents a two-steps process which aims to reduce the structure borne road noise due to floor panel using a coupled simulation with MSC NASTRAN and Actran. The embossment of the supporting steel structure, the material properties of porous layers and the thickness of visco-elastic patches are the design variables of the optimization process.

In times when automated driving is becoming increasingly relevant, dynamic simulators present an appropriate simulation environment to faithfully reproduce driving scenarios. A realistic replication of driving dynamics is an important criterion to immerse persons in the virtual environments provided by the simulator. Motion Cueing Algorithms (MCAs) compute the simulator’s control input, based on the motions of the simulated vehicle. The technical restrictions of the simulator’s actuators form the main limitation in the execution of these input commands. Typical dynamic simulators consist of a hexapod with six degrees of freedom (DoF) to reproduce the vehicle motion in all dimensions. Since its workspace dimensions are limited, significant improvements in motion capabilities can be achieved by expanding the simulator with redundant DoF by means of additional actuators.