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In order to optimize the function of an automobile seat, its geometrical and physical properties must be designed so that the loads resulting from the body weight and ambient factors (such as vibration, forces arising from vehicle dynamics, climatic conditions) act on the body of the occupant in such a way that the stress to which it is subjected is kept to a minimum. The physically measurable loads subject the driver to stress, i.e. they act mainly by changing biological processes in the organism, and drivers of widely different body statures must be considered. So the “correct” seat will necessarily be a compromise. From a careful integration of all requirements using the latest techniques, it emerged that an all-foam seat cushion incorporating varying degrees of firmness could be used to advantage. In this way Audi succeeded relatively quickly in designing a seat arrangement with remarkably positive characteristics.

Lightweighting of cars will remain one important goal for car producers. One milestone for lightweight technologies was the Audi Space Frame ASF‚. New generations of ASF cars will follow. Only the experience from the A 8 shows, which innovative technologies for these new generations will bring us one step forward. It's the combination of alloy modifications, innovative forming and joining technologies that leads into the future.

With battery electric vehicles (BEV), due to the absence of the combustion process, the rolling noise comes even more into play. The BEV technology also leads to different concepts of how to mount the electric engine in the car. Commonly, also applied with the Audi e-tron, the rear engine is mounted on a subframe, which again is connected to the body structure. This concept leads to a better insulation in the high frequency range, yet it bears some problems in designing the mounts for ride comfort (up to 20Hz) or body boom (up to 70Hz). Commonly engine mounts are laid-out based on driving dynamics and driving comfort (up to 20Hz). The current paper presents a new method to find an optimal mount design (concerning the stiffness) in order to reduce the dynamic chassis forces which are transferred to the body (>20Hz). This directly comes along with a reduction of the sound pressure level for the ‘body boom’ phenomena.

The aim of this investigation is the improvement of the lateral vehicle dynamics by optimizing the rim width. For that purpose, the rim width is considered as a development tool and configured with regard to specified targets. Using a specifically developed method of simulation, the influence of the rim width is analysed within different levels - starting at the component level “tyre” and going up to the level of the whole vehicle. With the help of substantial simulations using a nonlinear two-track model, the dimensioning of the rim width is brought to an optimum. Based on both, tyre and vehicle measurements, the theoretical studies can be proved in practice. As a result, the rim width has a strong influence on the behaviour of the tyre as well as on the overall vehicle performance, which emphasises its importance as a potential development tool within the development of a chassis.

In recent years, driving simulators have become a valuable tool in the automotive design and testing process. Yet, in the field of vehicle dynamics, most decisions are still based on test drives in real cars. One reason for this situation can be found in the fact that many driving simulators do not allow the driver to evaluate the handling qualities of a simulated vehicle. In a driving simulator, the motion cueing algorithm tries to represent the vehicle motion within the constrained motion envelope of the motion platform. By nature, this process leads to so called false cues where the motion of the platform is not in phase or moving in a different direction with respect to the vehicle motion. In a driving simulator with classical filter-based motion cueing, false cues make it considerably more difficult for the driver to rate vehicle dynamics.

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.

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”.

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.

Battery-electric vehicles (BEVs) require new chassis components, which are realized as mechatronic systems mainly and support more and more by-wire functionality. Besides better controllability, it eases the implementation of integrated control strategies to combine different domains of vehicle dynamics. Especially powertrain layouts based on electric in-wheel machines (IWMs) require such an integrated approach to unfold their full potential. The present study describes an integrated, longitudinal vehicle dynamics control strategy for a battery electric sport utility vehicle (SUV) with an electric rear axle based on in-wheel propulsion. Especially the influence of electronic brake force distribution (EBD) and torque blending control on the overall performance are discussed and demonstrated through experiments and driving cycles on public road and benchmarked to results of previous studies derived from [1].

Headlamp performance has changed in the last 20 years significantly. Sealed beam lamps were replaced by VHAD, VOR and VOL types, but still the optical input in terms of tungsten filament based luminous flux remained more stable. With Xenon discharge lamps and now LED the performance of a headlamp may vary strongly and thus the optical performance. Various rating systems have been developed to assess the quality of lamps and light distribution, some based on laboratory based data, some based on static or dynamic street test drives with online measurements and assessments. Basic interest is to understand the performance of the light for a real driver. This article will discuss the influence parameters on achieving a repeatable and precise rating as well as the outer influence that creates glare and varying seeing distance. Mostly mechanical headlamp and car conditioning will influence the result as well as human factors like aiming precision and aiming tolerances.

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.

Digitalization in Industry and Society is progressing quickly. Up to now, just 5 static and standard lighting applications have been dominating in the U.S. (Low/High Beam, Daytime Running Lamp Turn Indicator & Position Lamp). The global interest in standardization of light driven messages from autonomous vehicles to other traffic participants has opened new research needs and research findings. In Europe, GTB has established a working group dedicated to this topic. The article will discuss the possible contribution of signalling and lighting functions to Digitalization and Autonomous driving by explaining the first elements of functional definition and research results.

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.

In addition to the low and high beam functions, some modern headlamps also have the option of switching on only section of the high beam. The so-called adaptive high beam is intended to increase the detection distance of objects and through that drastically improve the road safety. At the same time, this function does not increase the glare for oncoming or preceding traffic. This is enabled through switching the different segments of the high beam on or off, depending on which and where other road users are recognized by the front camera. This massively increases the use of the high beam, thus increasing road safety. In this study, the increase in the detection distance of objects on a straight line is statically investigated with a test person study. Furthermore, the glare of each of these three light functions is observed.

The interaction between cooling-air and external aerodynamics is known as interference. In a conventional car this interference under the hood results in additional drag. It is estimated that about 10% of the overall aerodynamic drag originates from the cooling air [1] depending on the car shape and cooling configuration. Obviously, cooling drag should be minimized for vehicles with low-drag aerodynamics. In this study cooling-air interference-effects are investigated through experimental, numerical and analytical methods with a focus on the surface pressure of the vehicle. The surface pressure of vehicles with and without interference effects is compared. Observations show that when the cooling-air inlet is opened a pressure rise occurs around the inlet, while a pressure drop appears around the outlet. This phenomenon was investigated for several vehicle shapes including a simplified bluff-body (SAE-Body) and a close-to-real quarter-scale model (aeromodel).