Skip to main content
main-content

Über dieses Buch

In einer sich rasant verändernden Welt sieht sich die Automobilindustrie fast täglichmit neuen Herausforderungen konfrontiert: Der problematischer werdende Rufdes Dieselmotors, verunsicherte Verbraucher durch die in der Berichterstattungvermischte Thematik der Stickoxid- und Feinstaubemissionen, zunehmendeKonkurrenz bei Elektroantrieben durch neue Wettbewerber, die immer schwierigerwerdende öffentlichkeitswirksame Darstellung, dass ein großer Unterschiedzwischen Prototypen, Kleinserien und einer wirklichen Großserienproduktion besteht.Dazu kommen noch die Fragen, wann die mit viel finanziellem Einsatz entwickeltenalternativen Antriebsformen tatsächlich einen Return of Invest erbringen, wer dienotwendige Ladeinfrastruktur für eine Massenmarkttauglichkeit der Elektromobilitätbauen und finanzieren wird und wie sich das alles auf die Arbeitsplätzeauswirken wird.Für die Automobilindustrie ist es jetzt wichtiger denn je, sich den Herausforderungenaktiv zu stellen und innovative Lösungen unter Beibehaltung des hohenQualitätsanspruchs der OEMs in Serie zu bringen. Die Hauptthemen sind hierbei,die Elektromobilität mit höheren Energiedichten und niedrigeren Kosten der Batterienvoranzutreiben und eine wirklich ausreichende standardisierte und zukunftssichereLadeinfrastruktur darzustellen, aber auch den Entwicklungspfad zum schadstofffreienund CO2-neutralen Verbrennungsmotor konsequent weiter zu gehen. Auch dasautomatisierte Fahren kann hier hilfreich sein, weil das Fahrzeugverhalten dann –im wahrsten Sinne des Wortes - kalkulierbarer wird.Dabei ist es für die etablierten Automobilhersteller strukturell nicht immer einfach,mit der rasanten Veränderungsgeschwindigkeit mitzuhalten. Hier haben Start-upseinen großen Vorteil: Ihre Organisationsstruktur erlaubt es, frische, unkonventionelleIdeen zügig umzusetzen und sehr flexibel zu reagieren. Schon heute werdenStart-ups gezielt gefördert, um neue Lösungen im Bereich von Komfort, Sicherheit,Effizienz und neuen Kundenschnittstellen zu finden. Neue Lösungsansätze,gepaart mit Investitionskraft und Erfahrungen, bieten neue Chancen auf dem Weg derElektromobilität, der Zukunft des Verbrennungsmotors und ganz allgemein für dasAuto der Zukunft.

Inhaltsverzeichnis

Frontmatter

Motion control solutions for automated driving systems at BMW

Aside from technological trends, such as electrification and digitalization, automotive development is currently dominated by maturing the level of Autonomous Driving. Latest BMW models are already supporting the driver with an extensive portfolio of advanced driving assistance systems (ADAS) in the areas of driving comfort, active safety and parking [1, 2]. The maturity of these systems, and their level of automation can mainly be categorized as level-1 (driver assistance) and level-2 (partial automation) [3].

Alexander Kron, Immanuel Schaffer, Jeffrey Tchai, Karl-Heinz Meitinger, Stefanie Schraufstetter

Is a typical Mercedes-Benz Driving Character still necessary with an increasing number of driver assistance systems?

If you read the German automotive press one can get the impression that the journalists know the character of the brand Mercedes-Benz. Expressions like “A Benz like it should be.” or “a Daimler with typical values …” underline the character of the Mercedes-Benz driving behavior. This expectation is also there for our customers. Expressions like “the Mercedes under the …” demonstrate this assessment.

Stefan Botev, Horst Brauner, Ludger Dragon

Reasons why customers will still buy premium (chassis) in the age of automated driving

Armin Schöpfel

Technical scenarios for the decarbonization of road transport

Stephan Neugebauer

Comparative evaluation of PtX processes for renewable fuel supply

With the adoption of the Paris Climate Agreement on December 12, 2015, the international community committed itself to limiting global warming to below two degrees Celsius compared to the pre-industrial era. Germany’s contribution to achieve the climate protection targets was ratified by the German government in November 2016 introducing a policy document called “Klimaschutzplan” 2050’ [1]. Within this document the German government intends to reduce the greenhouse gas (GHG) emissions by at least 55 % by 2030 and 80–95 % by 2050 compared to 1990 levels [2].

Maximilian Heneka, Wolfgang Köppel

Modelling of real fuels for an effective virtual engine development with focus on alternative fuel

The worldwide environmental issues are affecting the development processes in all industrial sectors. Among these, the automotive is probably the one facing the toughest challenges. The reduction of both harmful emissions (CO, HC, NOx, etc.) and gases responsible for greenhouse effects (especially CO2) are mandatory aspects to be considered in the development process of any kind of propulsion concept.

Francesco Cupo, Marco Chiodi, Michael Bargende, Daniel Koch, Georg Wachtmeister, Donatus Wichelhaus

Sustainable drive concepts for future Motorsports

Global warming caused by greenhouse gas emissions is one of the major threats to humankind and challenges the automobile industry. Motorsport as a pioneer and a laboratory for automotive technologies has to face this issue and push the development of solutions. Nowadays motorsport is dominated by conventional propulsion systems powered by fossil fuels, predominantly by gasoline.

Lea Schwarz, Michael Bargende, Stefan Dreyer, Ulrich Baretzky, Wolfgang Kotauschek, Florian Bach

Automotive clusters in Germany and Baden-Württemberg

In January 2019, in an article about job cuts at Ford and JLR, Automobilwoche wrote that “the end game in the automotive industry has begun”. The signs are unmistakable. At increasingly shorter intervals in the last few months, the article says, profit warnings have been issued and dire forecasts made. Now, it continued, things are also coming to a head in Europe: British auto maker JLR (which belongs to Tata, the Indian company), Ford and Kuka have announced job cuts in Europe.

Albrecht Fridrich

The role of clusters in supporting French automotive industry’s competitiveness and innovation

The European automotive industry is one of the most performant ones in the world, and the sector is crucial for Europe’s economy. The automotive sector directly and indirectly employs 13.3 million Europeans, representing 6.1% of total EU employment. The European automotive export totalled 5.9 million motor vehicles in 2017 worth a trade surplus of €90.3 billion.

Thomas Röhr

The potential of collaborative business model innovation in automotive eco-systems

After decades of growth and success the automotive industry is facing heavy turbulences and upheavals. The era of Diesel engines for passenger cars seems to be coming to an end. Across the board, the future of all combustion engines is being questioned. In China, one of the most important automotive markets, sales of electric vehicles have increased by more than 50 % in 2018, whereas sales of cars powered by combustion engines have been falling steadily since 2nd half of 2018. State imposed minimum quota for EVs and further incentives, like an immediate car registration, will accelerate this development further.

Georg von der Ropp

Denoxtronic 5.3 – A modular system for applications worldwide

Diesel engines will play an important part to reach future CO2-limits for on-road mobility in the passenger car (PC) and light duty (LD) segment. High efficiency and compliance with new emission legislations are drivers for further improvements of the technology for markets like Europe with EURO 6, enforced by introduction of European Real Driving Emissions in two steps (mid 2017 & beginning of 2020), but also China (CHINA 6) and India (Bharat Stage VI), where comparable legislations will be implemented in 2020.

Michael Raff, Erik Weingarten, Manuel Muslija

Modular HD – Exhaust gas treatment system with autarcic thermal management for high urban NOx conversion

With the European Directive 2008/50 EC on Ambient Air Quality [1], the European Commission is pursuing the goal of ensuring that the annual average ambient air quality limit of 40 μg/m3 for NO2, which has been in force since 2010, is ensured. Compliance with this directive is a major challenge for many municipalities and federal states.

Klaus Schrewe, Bernd Maurer, Christoph Menne, Ingo Zirkwa

New experimental insights in AdBlue-spray/wall interaction and its impacts on EGT system design

With the introduction of new emission legislation (e.g. EU6-RDE, LEVIII/SULEV) and related nitrogen oxides (NOx) emission limitations, the automotive industry is facing new challenges concerning efficient and robust exhaust gas treatment (EGT). For conversion of NOx, selective catalytic reduction (SCR) via AdBlue has prevailed in Diesel exhaust gas treatment. The preferably complete reduction of NOx in EGT systems still remains one of the most important and challenging tasks of today’s powertrain development.

David Schweigert, Björn Damson, Hartmut Lüders, Carsten Becker, Olaf Deutschmann

Environmental model extension for lane change prediction with neural networks

Driven by the desire of improving traffic safety, traffic efficiency and a better utilization of the time people spend in traffic, the development proceeds from Advanced Driver Assistance Systems (ADAS) towards fully automated systems. ADAS systems are categorized as level 2 systems according to the Society of Automotive Engineers (SAE) [1] definition, on a classification scheme from level 0 to 5 where level 5 is a fully automated system. With increasing automation level the complexity rises, due to the piecewise shift of responsibility towards the automated driving system.

Martin Krüger, Anne Stockem Novo, Till Nattermann, Manoj Mohamed, Torsten Bertram

Requirements & evaluation of friction information for the integration in vehicle systems

Increasing levels of automation in driver assistance systems (DAS) require safeguarding the steer and brake intervention in order to further prevent accidents. Special attention must be given to the interaction between tires and road surface. The friction coefficient between road (μ) and tires has a significant impact on driving performance and safety. Figure 1 illustrates that a very high percentage of the accidents happen in wet, snowy or icy road conditions.

Staiger Sebastian, Nosrat Nezami, Dieter Schramm

Kinetosis in autonomous driving

Autonomous driving is a current research and development topic. Mostly, the focus is on the technical implementation including artificial intelligence. However, further aspects like ‘social and ethic aspects’, ‘legal aspects’ and ‘ergonomics and physiological requirements’ should be taken into consideration. The latter point includes the kinetosis (travel sickness), which is often neglected, but plays an import role in autonomous driving: While the car is driving autonomously, passengers in the car are often sitting sideways or backwards, which can cause travel sickness (= motion sickness).

Carsten Lecon

One-Stop-Test solutions for autonomous driving

Frank Heidemann

Phenomenology and analysis of gas pressures at low-speed pre-ignitions

Bei Ottomotoren hat das Phänomen der Vorentflammung mit zunehmendem Downsizing an Bedeutung gewonnen. Brüche des ersten Ringsteges oder des Feuersteges können bereits nach wenigen Betriebsstunden zu Motorschäden führen, leider nicht nur in der Erprobung. Für die Auslegung von Kolben gegen das Versagen unter Vorentflammung ist die Anwendung realitätsnaher Lastfälle entscheidend, aber klassische Verfahren greifen hier nicht mehr.In diesem Beitrag wird eine neue Methode der Messung und Simulation zur Ableitung realistischer Druckrandbedingungen bei Vorentflammung am Kolben vorgestellt. Diese Anwendung der Gasdynamik bei der Ausbreitung von Druckwellen aus der Vorentflammung führt zu einer guten Korrelation von Versuch und Simulation. Mit der FEM lassen sich durch diese neue Methode typische Schäden am Kolben gut erklären.Probleme bestehen weiterhin in der stochastischen Variation der Druckamplituden bei den realen Vorentflammungen im Motor und der nachfolgenden Schadensakkumulation. Dennoch erlauben die gefundenen Phänomenologien der Druckwellenausbreitung schon eine schlüssige Ursachenanalyse der in der Praxis gefundenen Schäden.

Christoph Beerens, Rainer Fischer, Christian Trabold

Combustion stability improvement with turbulence control by air injection for a lean-burn SI engine

Minimizing crude oil consumption is one of the major challenges for automotive industry to keep a sustainable society. Especially, transportation is one of the major sectors of energy consumption [1] and therefore improvement of thermal efficiency is one of the important roles for automotive engine systems.

Takanori Suzuki, Bastian Lehrheuer, Tamara Ottenwälder, Max Mally, Stefan Pischinger

Air intake temperature cooling thanks to pressure wave action and adapted air intake geometry

As powertrain electrification gains popularity, gasoline engines must work to keep up with new performance demands and strict emission regulations. As such, a new gasoline engine must be engineered for high performance and high efficiency, as well as for acceptable CO2 levels and the European Union’s Real Driving Emission (RDE). To maintain this tradeoff, for new GTDI engines, lambda 1 upstream of the 3 way catalyst needs to be ensured.

Vincent Raimbault, Jérôme Migaud, Heinz Bühl, Stéphane Guilain, David Chalet, Michael Bargende

Future e-mobility and the change in system requirements

Mobility of tomorrow is undergoing a radical change. Against the background of increasing electrification, automated driving, the connectivity of vehicles and ever stricter CO2 regulations, not only the powertrain technologies (e.g. BEV, FCEV, …) but also its usage profiles (e.g. robo-taxi, car sharing, …) and thus the requirements of the vehicle components will change considerably.

Lothar Schindele, David Schütz, Gaël Le Hen, Norbert Müller

Active materials for electrical motors – Leverage for reducing costs and increasing performance

Driven by new social, environmental and economic challenges the automotive industry has to face those challenges in order to offer fascinating products for the costumer. The so-called CASE trends will lead to a fundamental change in the automotive industry.

Moritz Kilper, Hristian Naumoski, Steffen Henzler

Traction energy saving potentials for electric cars with gear shift

The efficiency of electrical traction drive chains is quite good (i.e. above 80%) in a wide operation range, while for low speed or small torque operation, efficiency falls significantly. In realistic load cycles, electric drives often have to work with efficiency levels below 60%. This is elucidated in Fig. 1 for the experimental vehicle shown in Fig. 2. In this contribution, the motor characteristics with efficiency mapping are given for the complete drive chain (battery – current converter – motor – gearboxes – wheel).

Oliver Zirn, Fabian Schmiel, Matthias Dellermann

Impact of modulation strategies on the power losses of the dc-link capacitor of an inverter

Power losses within the powertrain of electric vehicles are crucial for the efficiency as well as the thermal load of its main components. Due to the limited robustness with regard to thermal degradation, the dc-link capacitor of a traction inverter requires good knowledge of its power dissipation. The harmonics occurring in the dc-link current are of vital importance considering the thermal stress on components of the dc-link circuit. Using different modulation strategies, various quantities of the powertrain can be positively influenced and are accompanied by a change of the harmonic characteristics. The effect of the voltage modulation needs to be considered appropriately in a loss model. Therefore, in this paper a new generic approach for the calculation of the current and the related power loss of the dc-link capacitor is presented. The validity of the algorithm was verified by simulation applying two different types of voltage modulation: space vector pulse width modulation (SVPWM) and six-step mode (SSM). The analyses indicate a high accuracy of the loss model with a maximum error of less than 2 %. Using SSM a reduction of the power dissipation of the capacitor of nearly 97 % against the standard modulation strategy SVPWM could be proven. As a result, the outlined methodology may be a basis for real-time computation of the power losses and a thermal protection function of a dc-link capacitor using a broad spectrum of modulation strategies.

Maximilian Weber, Michèle Hirsch, Helge Sprenger, Thomas Zeltwanger, Hans-Christian Reuss

The six-step mode: Unwanted or rather the ideal voltage modulation method

In today’s electric and (plug-in) hybrid vehicles, properties such as the overall driving efficiency are an essential design goal next to its pure drivability characteristics. Component costs and power rating are additional factors to determine the commercial success of the product. Different voltage modulation methods and their configuration may be considered in design decisions to further optimize the electric drive train system.

Thomas Zeltwanger, Helge Sprenger, Mark Damson, Manabendra N. Gupta

Design of a fail-operational powertrain for automated electric vehicles

Automated vehicles will change the role of privately owned cars in the future. New mobility solutions like Urban Automated Shuttles (UAS) and Urban Automated Taxis (UAT) can provide mobility as a service with a lower price. As a result, most urban and suburban residents will be able to be mobile without owning a car.

Tunan Shen, Ahmet Kilic, Jochen Faßnacht, Christian Thulfaut, Hans-Christian Reuss

A scalable approach for future vehicle electrification

Carsten Bünder

Grid integration e-mobility – Developments and challenges

The charging interface between grid and electric vehicles is new. To integrate the “two worlds” power supply and vehicle for many challenges solutions have to be found and introduced. Many different requirements for charging are considered: electric vehicles are charged in private environments, at work place or at public charging infrastructures.

Ursel Willrett

Validation of range estimation for electric vehicles based on recorded real-world driving data

Electrification of vehicles is a growing trend in the automotive industry. Battery electric vehicles offer the potential to reduce greenhouse gas emissions, but short maximum range and missing charging infrastructure limits user acceptance. Range anxiety is a great challenge for battery electric vehicle drivers, therefore accurate methods for range estimation are required to satisfy customer needs.

Patrick Petersen, Jacob Langner, Stefan Otten, Eric Sax, Stefan Scheubner, Moritz Vaillant, Sebastian Fünfgeld, F. Porsche

Smart grids in mobile fleet operations

In a mobile industrial fleet application different machinery is powered by each its own reciprocating internal combustion engine. EKU Power Drives (EKU) is focusing on increasing the energy efficiency of these fleet applications.Therefore, the combustion engines are enhanced to mild hybrid units and connected to a smart grid. This semi-automated fleet setup allows to dynamically share load between units or manage the usage of equipment to streamline operational procedures. Single combustion engines are entirely replaced by electric drives and powered by the excess power of the remaining hybrid engines and the grid. The increased load on the remaining engines results in specific fuel consumption advantages. This increases the efficiency of the entire fleet. Economically the achieved fuel savings are only a portion of the gained benefits. On the fleet perspective the necessary number of engines has been reduced and the individual load on the remaining has increased. Operators’ biggest cost savings result from less different engines to maintain and store spare parts.With the power need of the grid and the capability of the electrified auxiliary engine drives, concepts for electric motors and batteries are defined. A suitable net topology concept is developed, and the independent grid is controlled by a distributed cooperative closed loop control. This enables a configuration-less connection setup between different machinery of the fleet.

Dusko Mitrovic, Manuel Klein, Leonardo Uriona, Marius Klein, Kristian Binder, Edward Eichstetter, Michael Weyrich

Infrared-based determination of the type and condition of the road surface

The knowledge of different road conditions is a significant factor in determining their impact on fully automated driving. As part of the research project “SeeRoad” funded by the German Federal Ministry for Economic Affairs and Energy (BMWi), a system with various technological approaches is being developed, in order to estimate road conditions. One of these approaches determines the condition of road surfaces as well as the distance between the vehicle or sensor and the road surface, based on infrared (IR). In order to distinguish between a wet and a dry surface, the water film height (WFH) is measured by infrared rays. We present a procedure for determining the type and condition of the road surface with the help of infrared radiation, which forms a basis for the multiple sensor system. This procedure is tested in a laboratory setup that is suitable for reproducible measurements. A new approach to detect road surface wetness by using a combination of infrared sensors, which work with different principles, is presented. The first principle is based on the intensity measurement of a reflected IR signal to determine the distance. Here the intensity depends on the material surface. At a constant distance, different intensities are measured for the absorbed and reflected signal, depending on the color and texture of a material. In the second principle, the transit time of the emitted and reflected beam is measured, which is independent of the intensity. Thus, the combination of both methods allows the distance and type of road surface to be calculated.

Lakshan Tharmakularajah, Jakob Döring, Karl-Ludwig Krieger

Essential predictive information for high fuel efficiency and local emission free driving with PHEVs

An intelligent selection of the operating modes can improve the fuel efficiency of plugin hybrid electric vehicles (PHEVs) and allow them to drive local emission free. In order to align these goals and hence to improve the mobility especially with air pollution problems in urban areas, predictive information about future driving situations is necessary. To achieve this target and furthermore to design and calibrate predictive control strategies accordingly, the sensitivity of predictive information on the fuel efficiency is analyzed in the presented simulation study. Traffic simulations are used which enable reproducible driving situations regarding traffic, traffic control and driving characteristics by their parameterizable settings. By calculating fuel optimal strategies with Dynamic Programming (DP) for a PHEV in P2 topology, the impact of predictive information about future driving situations on the fuel efficiency is evaluated. The results show which driving situations are suitable for charging and discharging and assess the efficiency of local emission free driving by comparing the fuel savings to the costs of the electric energy demand.

Tobias Schürmann, Daniel Görke, Stefan Schmiedler, Tobias Gödecke, Kai André Böhm, Michael Bargende

Analogy considerations for the design of hybrid drive trains

Development engineers for hybrid drive chains need a suitable understanding of the application of the internal combustion engine (ICE) as well as the electric motor (EM) subsystem. The actual literature in applied textbooks consider EM’s from the perspective of the electrical machine developer with emphasis on the magnetic circuit, winding techniques and power electronic control [2]. In theoretical literature, EM’s are treated on a quite abstract and analytical level (flux linkage and field-oriented control) for the electrical engineer. This makes it difficult for developers coming from classic automotive engineering to accomplish a deeper understanding of electric drives.

Michael Auerbach, Oliver Zirn

Hybrid operating strategies in the trade-off between fuel consumption and emissions

Sven Eberts, H.-J. Berner, Michael Bargende

External water management: A predictive challenge

Predictive capabilities of film, rivulet and drop transport on vehicle surfaces are desirable, since experimental investigations are complex and only possible at late stages of vehicle design. However, simulations and/or experiments remain essential, either related to wing-mirror sight demands or, more recently, to insure proper operation of sensors and/or imaging devices. Major difficulties are presently apparent with such predictions, because physical models describing basic wetting phenomena encountered on typical vehicle surfaces and geometries are lacking or are not implemented in numerical codes. These include processes such as wettability influence on drop impact and splashing, shear-driven film-rivulet-drop transition, incipient motion of drops, drop interaction with grooves and material discontinuities, film/rivulet/drop stripping from edges, etc. Improvements to present models implemented in simulation codes can only be expected once a basic physical understanding of these processes is acquired. The present contribution summarizes the main challenges in developing models and outlines a series of generic experiments with the express purpose of meeting these challenges. The structure of such models at the micro through to the macro scale is described. Implementation of these models in existing codes is also discussed and the outlook for a prediction of external water management is drawn.

Cameron Tropea, Johannes Feldmann, Daniel Rettenmaier, Patrick M. Seiler, Michael Ade, Daniel Demel

Aerodynamic study on the vehicle rear shape parameters with respect to ground simulation

The automotive market today is being divided into more detailed segments than before to meet the diverse demand of customers. Correspondingly, the vehicle basic shape especially the rear end shape becomes more numerous. In addition to the three typical rear end shapes – notchback, fastback and squareback – some new concepts are derived from a mixture of those classic rear end shapes. For example, as demonstrated in Figure 1, an SUV-coupe like vehicle has a much higher trunk and a more raised trunk lid slope angle than a normal limousine or coupe. On some limousine models like the Porsche Panamera Sport, the rear end shape is designed as a fastback. Its rear screen angle is smaller than a station wagon. Moreover, the rear underbody diffuser is often equipped to improve the vehicle road behavior.

Chenyi Zhang, Daniel Stoll, Timo Kuthada, Jochen Wiedemann

Development of an SUV reference model for aerodynamic research

With the introduction of WLTP, the effect of aerodynamics on the overall emissions is increased. Aerodynamic research can help to reduce the drag of a vehicle with new measures, resulting in a further reduction of the fuel consumption. Therefore, openaccess reference models are needed, that can be used for investigations and CAE method development. These vehicle models need to reproduce the flow details of the basic shape as well as the essential flow structures of the corresponding vehicle.In the global market, SUVs obtain the strongest growing market share. For this vehicle class no model is available, that features a high level of detail. Therefore, this work focuses on the development of the AeroSUV. To depict an SUV, this type of vehicle has to be characterized at first by an analyzation of the legal requirements of the EU and USA. This is added by mean dimensions of 17 models available in the market. The resulting requirements are used to create a first sketch of the model. To replicate a realistic shape, the AeroSUV is optimized using CFD. The resulting geometry is builtup in 25 % scale and investigated in the model scale wind tunnel (MWK) of the University of Stuttgart. The geometry of the AeroSUV is open-access and available on the ECARA website ( http://www.ecara.org/ ).

Max Tanneberger, Chenyi Zhang, Timo Kuthada, Felix Wittmeier, Jochen Wiedemann, Juliane Nies

Lamborghini Aventador SVJ Aerodynamics: Route to breaking the super sport car’s record

Ugo Riccio, A. Torluccio

Attribute-based development of Advanced Driver Assistance Systems

Advanced Driver Assistance Systems and Automated Driving are a megatrend in the automotive industry. The following questions arise: Will vehicle manufacturers still be able to differentiate themselves “brand-specifically” in the future or will all vehicles be perceived the same when being driven? How can a brand DNA be implemented and how can the transfer of “fun to drive” to “fun to be driven” be achieved? In order to reach this, clear driving characteristic goals – in front of the customer – should be defined and the requirements for vehicle systems and components shall be derived from this. However, what are driving characteristics in the context of assisted and automated driving, Figure 1, and how can those specifically be achieved in the development? Porsche has addressed this question together with the University of Applied Sciences Kempten and MdynamiX. How can an attribute-based development look like and how can Porsche effectively design a brand-typical characteristic in this area?

Bernhard Schick, Florian Fuhr, Manuel Hoefer, Peter E. Pfeffer

ITC – Integrated traction control for sports car applications

Due to the great success of Bosch Engineering’s nonlinear model based lateral dynamics controller Integrated Vehicle Dynamics Control (IVC), the concept has now been expanded to traction control systems. Based on the method of exact linearization, a feedforward algorithm is presented. This is done by taking the nonlinearities of tire behavior with combined lateral and longitudinal slip conditions into account. Asymptotic stability of the closed loop is established using a model based linear feedback controller, enhanced by gain scheduling and anti-windup algorithms as well as optimized initial condition values. Damping and robustness properties are investigated by applying frequency domain methods. In order to reduce communication delay, the engine ECU is integrated into the controller computations. By integrating the active differential into the traction control algorithm a multivariable controller is established. The performance of the proposed control algorithm is demonstrated by means of road tests that are carried out with a rear wheel driven sports car under high-μ conditions.

Lars König, Frieder Schindele, Andreas Zimmermann

Computation time optimization of a model-based predictive roll stabilization by neuro-fuzzy systems

The present article discusses the possibility to reduce the computational effort of complex control algorithms by neuro-fuzzy systems. Thereby, great potentials can be released, especially in the automotive sector. A limiting factor for the design of control algorithms is the task of a real-time execution on cost-optimized control units [1]. The influence of this limitations can be reduced by neuro-fuzzy systems. This is shown exemplary for the model-based predictive control of the roll motion presented by Sieberg et al. [2]. The controller based on the adaptive neuro-fuzzy inference system is validated regarding the control quality and the computational effort. Thus it is compared to the origin model-based predictive control algorithm. The implementation and validation are based on a co-simulation of MATLAB/SIMULINK and IPG CarMaker.

Philipp Maximilian Sieberg, Markus Schmid, Sebastian Reicherts, Dieter Schramm

Integrated approach for the virtual development of vehicles equipped with brake control systems

Since the introduction of the brake control system Electronic Stability Control (ESC) in 1995 an increasing number of vehicles was equipped with the system and it became statutory for new registered vehicles in 2014, e.g. in Europe, the United States and Australia [1] [2]. Representing a vehicle dynamic control system, the ESC assures predictable, stable and controllable vehicle behaviour, even at the limits of driving dynamics [3]. Several studies prove the effectiveness of ESC in reducing severe and fatal accidents [4] [5]. In consequence, the consideration of the brake control system is an important issue in every vehicle development.

Fabian Fontana, Jens Neubeck, Jochen Wiedemann, Ingo Scharfenbaum, Philippe Stegmann, Armin Ohletz, Uli Schaaf

New entry OEM – A global phenomenon

The number of so-called new entry OEM is growing constantly and is not only restricted to the Chinese marketplace (refer to figure 1). Besides, the business motivation for these companies to enter the automotive markets differs significantly. This presentation deals with the new entry OEM’s heritage, motivation and the technical challenges that have a significant impact on the automotive industry and engineering service providers like Magna Steyr. This presentation describes two different approaches – the “Uber”-approach and the “Tesla”-approach.

David Ludwig

Consistent application of systems engineering and simulation for cross-domain function integration

The automotive megatrends (electrification, automation, connectivity) and new mobility concepts lead to an increasing interaction of mechatronic systems with their surrounding systems and finally to an increased interaction with the entire vehicle. This leads to changed boundary conditions for OEMs and Tier1 suppliers.

Marcus Boumans, Martin Johannaber, Ulrich Schulmeister

Automotive megatrends and their impact on NVH

The ongoing transformation of individual mobility will decisively change future vehicles. The acronym CASE, created by Daimler in 2016, sums up four megatrends in one abbreviation: Connected, Autonomous, Shared and Electric. This paper is meant to discuss the resulting consequences regarding NVH. The strong impact on vehicle NVH requirements is evaluated and suggestions for a suitable sound design are made. Sharing the same vehicle by many users will reduce the importance of creating an individual brand specific sound, instead active sound design would allow tuning the interior noise to the preferences of the current user. Electrified vehicles, which feature a very quiet drivetrain, create new challenges for the NVH development in several ways: unpleasant, high frequency noise from the drivetrain, less masking of disturbing noise such as road and wind noises, basic questions concerning brand sound with the completely new sound character of the electric drivetrain. NVH requirements for autonomously operating vehicles will differ significantly from conventional vehicles. The situation of the user is similar to that of a “train passenger”. Comfort oriented NVH features will become more important, acoustic load response is expected to lose relevance.

Georg Eisele, Michael Kauth, Christoph Steffens, Patrick Glusk

Evaluation of the effects of trends on vehicle concepts based on a forecast of travel demand

Today, vehicle concepts are developed on the basis of technical design premises derived from attributes such as e.g. the electrical range in the case of electrified vehicles. For the respective positioning of the concept, the customer requirements of the relevant target group determined by market research and the competitive comparison are decisive. Technological trends (e.g. fully automated driving1; FAD) and business model innovations (e.g. on demand mobility; ODM) have the potential to change the mobility behavior of users and thus the characteristics of vehicle concepts.

Peter Lukas Peters, Rainer Demuth, Dieter Schramm

Potentials of modular autonomous vehicles for variable scenarios of public transport

On the way to new forms of mobility, a number of autonomous vehicles were built in recent years. In addition to tests with classic cars and trucks, which still have a driver’s seat with all the necessary control elements, the vehicle type of a small passenger shuttle has also been developed. These passenger shuttles have already completed some operation time successfully in a controlled environment.

Dennis Wedler, Thomas Vietor

Method for concept design and optimization of twist beam axles

The twist beam axle (TBA) is one of the most common type of rear axles. It was developed at first for the VW Polo [1, 2] based on the rigid axle. In comparison to a rigid axle whose wheels cannot move independently due to the direct connection between the two wheel carriers by a cross member, the relative movement of the two wheels in a twist beam is possible. There, the cross member is placed towards the vehicle front direction and connect the two trailing arms in a position between the wheel center and the body mount.

Xiangfan Fang, Kanlun Tan, Jens Olschewski

Technologies for a modular vehicle concept used in passenger and goods transport

At the beginning of the year 2019, vehicles with diesel internal combustion engines (Euro 4 or older) have been banned from entering the city of Stuttgart. This is the temporary climax of current efforts to address traffic-induced air pollution. More than 500 sanctions in several European cities try to ban private cars from cities.

Christian Ulrich, Horst E. Friedrich, Jürgen Weimer, Robert Hahn, Gerhard Kopp, Marco Münster

Experimental investigation of Miller cycle combustion technology with water injection

The future RDE legislation as well as the associated fleet consumption targets require a high efficiency of the gasoline engine under real driving conditions. Throttled operation is increasingly losing in significance for RDE in downsized gasoline engines. Conversely, engine operating points are increasingly being shifted toward high brake mean effective pressures in the boosted range. The knock limit frequently results in late centers of combustion, which are not optimal in terms of efficiency. Consequently, a high knock resistance of the gasoline engine is crucial for low fuel consumption under real driving conditions. In consideration of this, the Miller combustion cycle with early intake closing offers advantages with regard to efficiency. The additional use of water injection leads to a reduction of the cylinder charge temperature, which further increases the knock resistance. The combination of these two technologies in the interests of improved efficiency represents an attractive approach for future powertrain configurations.This article evaluates port water injection in comparison with direct water injection with regard to the potential for efficiency improvements. The article also demonstrates the thermodynamic effect of water injection on combustion and analyzes the emissions behavior. The experimental investigations are conducted on a newly developed singlecylinder engine based on the downsizing concept and with a high geometrical compression ratio.

Nils Neumann, Normann Freisinger, Guido Vent, Thomas Seeger

Reduction of cold start emissions with microwave heated catalytic converters

Emissions of Euro-6 gasoline powertrains at normal operating temperatures are almost zero (Fig. 1). On the contrary, during cold starts, characterized by low temperatures for the catalytic converters, CO and unburned hydrocarbon (HC) emissions are 2-3 orders of magnitude higher than during cruise operating conditions [1]. The situation is even more severe with hybrid powertrains. Here the intermittent engine operation often leads to numerous cold starts.

Viola Papetti, Panayotis Dimopoulos Eggenschwiler, Daniel Schreiber

Extended cylinder deactivation strategies to improve CO2 and pollutant emissions for light-duty diesel engine applications

Further improvement of the trade-off between CO2- and pollutant emissions motivates the development of new diesel engine concepts. The deactivation of one or more cylinders of a light-duty diesel engine during low load operation can be a sophisticated method to improve fuel economy and reduce especially NOX emissions at the same time.This publication presents the potential of extended cylinder deactivation (CDA) strategies by means of steady-state, 1D simulations in combination with transient powertrain simulations. The transient cycle investigations have been conducted using the Worldwide Harmonized Light Vehicle Test Procedure (WLTP) and Real Driving Emissions (RDE) cycles. A representative mid-size SUV, powered by a state-of-the-art 2.0 l, 4-cylinder diesel engine, was considered for these investigations. The engine is equipped with both high and low pressure EGR and a closed-coupled DOC/SCRF system with an additional underfloor SCR.The potential of a selective CDA of separate cylinders by Dynamic Skip Fire (DSF®) technology, as part of an extended CDA strategy, has been analyzed in detail. The results show a CO2-benefit of approximately 2 % under a RDE cycle, while simultaneously reducing tailpipe NOX emissions by approximately 11 %. These improvements have been achieved by an increased engine efficiency due to a shift in the engine operation conditions by the extended CDA strategies. Implementing these CDA strategies also results in higher exhaust temperatures which further improves the conversion efficiency of the aftertreatment system. Furthermore, the investigations have been extended to show the potential of this strategy when applied to an 8.0 l medium duty diesel engine application.

Kai Deppenkemper, Markus Schönen, Bernd Lindemann, Mauro Scassa, Matthew Younkins, Robert Wang

A new method for the objective assessment of ADAS based on multivariate time series classification

Advanced Driver Assistance Systems (ADAS) such as Adaptive Cruise Control (ACC) are appearing increasingly more often in modern premium cars and have great potential for increasing both comfort and safety. These gains are only appreciated by the customer, when the driving behavior of the system is perceived as positive, e.g., comfortable [1]. Therefore, the different calibrations of an ADAS must be assessed during the development process to ensure positive perceived comfort.

Uwe Moser, Nick Harmening, Dieter Schramm

Test methods of visual distraction by interaction with driver information- and assistance systems

Basierend auf vorhandenen Richtlinien zur Testung des Ablenkungspotentials von Fahrerinformations- und assistenzsystemen (NHTSA, ISO/TS 15007-2) wurden mit verschiedenen Fahrzeugtypen insgesamt vier Tests auf einer Rundstrecke durchgeführt. Die visuelle Ablenkung wurde mittels eye-tracking-System bei der Durchführung vorgegebener Tasks im Fahrversuch mit Probanden ermittelt. Fragebögen zur User-Experience und Expertenevaluierungen ergänzten die Beurteilung der Serienfahrzeuge. Eine statistische Auswertung der Ergebnisse erlaubt eine reproduzierbare Einschätzung des Grades der Ablenkung in einer realen Umgebung. Diese Vorgehensweise hat sich als tauglicher Kompromiss zwischen einer Simulator-Studie und Testfahrten im öffentlichen Verkehr erwiesen. Die Durchführung dieser Tests wird beschrieben, Ergebnisse zum Ablenkungsgrad vorgestellt und die Überleitung dieses Prozederes in eine Ö-Norm, die der Feststellung der durch Fahrerinformations- und assistenzsysteme verursachten visuellen Ablenkung dienen soll, aufgezeigt.

Thomas Stottan

Feasibility study on the basis of a prototype for automated vehicle positioning in inductive charging process

In this paper, the concept discussed in [5] is subjected to a feasibility study. The aim here was to determine the maximum possible positioning radius and the correct position of the magnetoresistive (MR) sensors. For the first time, the investigated concept solves the problem of automatic positioning via the inductive charging coil using the magnetic field-based measuring technology MPPS (Magnetic Pulse Positioning System) [1-4]. To perform the feasibility study, the concept was applied and implemented in prototype on a 1:5-scale model vehicle. Initially, the magnetic interference was investigated and identified. This primarily emanated from the drive and steering systems. Subsequently, the necessary reduction countermeasures were put in place. Based on these results, the optimal position of the MR sensors was determined and they were positioned relative to the MPPS. With the given sensor configuration and the test coil used, it was possible to achieve a maximum model vehicle positioning radius of 3 m. Positioning automation remained excellent at this distance. These results show that the concept discussed in [5] can be applied and implemented on a vehicle.

Matthias Hisung, Dean Martinovic, Hans-Christian Reuss

Continuous implementation of 0D/1D engine models in the development process of a race car engine

Due to the increasing complexity of engines and the limited resources virtual development methods are essential throughout the whole development process. Especially in motorsports, virtual engineering methods can accelerate the development and finally make a difference.

Simon Malcher, Michael Bargende, Stefan Dreyer, Ulrich Baretzky, Hartmut Diel, Wolfgang Kotauschek, Sebastian Wohlgemuth

Integrated flow model with combustion and emission model for VVT Diesel engine

In this work, a previously developed quasi-dimensional charge motion and turbulence model for the diesel engines with a fully variable valve train [4] is at first extended by enclosing injection effects and modeling internal exhaust gas recirculation (iEGR). Direct injection contributes to the immense generation of turbulence but also affects adversely swirl flows, for which it is modeled both as immediate partial conversion of injection kinetic energy into turbulent kinetic energy (TKE) and as an additional moment of inertia that decelerates swirl. In order to cope with the future application of iEGR, the variability on the exhaust side is taken into account.

Qirui Yang, Michael Bargende, Michael Grill

A 1D co-simulation approach for the prediction of pollutant emissions of internal combustion engines

The prediction of pollutant emissions generated by IC engines has been a challenge since the introduction of the emission regulation legislation. This paper describes the approach followed by the authors to strictly couple two different 1D modeling tools in a co-simulation environment, to achieve a reliable calculation of engine-out and tailpipe emissions. The main idea is to allow an accurate 1D simulation of the unsteady flows and wave action inside the intake and exhaust systems, without resorting to over-simplified geometrical discretization, and to rely on advanced combustion models and kinetic sub-models for the calculation of cylinder-out emissions.

T. Cerri, G. D’Errico, G. Montenegro, A. Onorati, G. Koltsakis, Z. Samaras, V. Tziolas, N. Zingopis, K. Michos, J. Rojewski, V. Papetti, P. Dimopoulos Eggenschwiler, P. Soltic

Fully integrated design exploration for in-cylinder simulation

We present a comprehensive efficient CFD based approach to virtually optimize the performance of a GDI combustion system from within a single simulation environment. In a first step the geometric designs space of the parametrized intake-port is explored to find better port designs. Studying 100 ports in a transient cold-flow simulation, improved designs can be identified best ones even doubling turbulent kinetic energy at ignition timing at only one percent penalty on trapped mass. In the second stage of the process the timings of a multi-pulse injection strategy are varied to further improve the turbulence level and fuel distribution homogeneity, thereby ensuring an ignitable mixture, minimum liquid fuel residual and fuel backflow into the intake by corresponding constraints. Studying 80 strategies allows the identification of better ones that improve TKE and fuel uniformity performance yet meeting the feasibility criteria in a highly constrained design space. A detailed correlation analysis of transient tumble, TKE and uniformity traces for some key injection strategies allows for a thorough understanding of the underlying physical mechanisms that lead to improved engine performance.

Warren Seeley, Simon Fischer

Performance evaluation of an IC-engine with a novel partial admission turbocharger concept

In 2015, a novel control concept for the partial admission of a turbocharger turbine named MEDUSA (Multiple Exhaust Duct with Source Adjustment) was presented at the Stuttgart International Symposium. The basic idea of this control concept is to divide the turbine inlet into several sectors along the circumference and to control the admission of the different sectors individually. This partial admission approach works similar to a Variable Nozzle Turbine (VNT) control system and allows to increase the turbine inlet pressure at low engine mass flows by closing turbine inlet segments and thus restricting the effective flow area. As a consequence higher turbocharger power output at low engine load conditions can be achieved.

Markus Schatz, Fabian Seeger, Damian M. Vogt, Sergej Koch, Denis Notheis, Uwe Wagner, Thomas Koch

The future bearing concept of BMTS Technology

In order to achieve the future CO2 fleet targets, it is necessary to continuously improve the efficiency of the combustion engine and its subcomponents [2,5]. Cost-conscious solutions for current and future volume applications are essential to realize a reasonable scaling in the fleet and maintain customer attractiveness. The turbocharger performance significantly influences the internal efficiency of the combustion engine process.

Rüdiger Kleinschmidt, Steffen Schmitt, Frieder Stetter, Oliver Kuhne, Simon Nibler, Gunter Winkler

Comparison of a chain driven vs. gear driven valve train in a commercial vehicle

The aim of this study is to show the feasibility of using chain technology in timing drives for heavy duty engines in terms of dynamics, NVH and durability and to point out the advantages of using a chain drive instead of a gear drive. For this purpose a theoretical and hardware study was initiated by iwis motorsysteme and carried out by FEV Europe GmbH.

Peter Bachmair, Christoph Biwer, Thomas Saupe, Thomas Fink

Dynamic friction behavior of a gasoline engine in transient operation

To minimize friction in the piston group of an internal combustion engine, systematic experimental testing must be performed on a number of design variants. A vehicle simulation can be used to determine fuel and CO2 savings of each variant in a driving cycle. Despite the transient operating conditions of the driving cycles, the analysis often uses friction maps measured in steady-state operation. This article therefore investigates whether a dynamic friction behavior occurs in transient engine operation. For this purpose, specific friction measurements with defined changes in operating point are taken. It appears that after changes in engine speed or load, both increases and decreases of friction can occur temporarily in comparison with measurements in steady-state operating conditions. The sign and magnitude of these differences depend on the specific change in operating point and on the engine temperature. The observed dynamic friction effects are characterized qualitatively and explanations of the underlying mechanisms are derived. Because the dynamic friction behavior can lead to a momentary difference of 15 % compared to the stationary friction value, friction measurements in transient engine operation appear to be sensible for evaluating savings potential in a driving cycle. It can be experimentally demonstrated, however, that dynamic friction phenomena have only a relatively low influence on cumulative fuel consumption and CO2 emissions.

Tobias Funk, Holger Ehnis, Reiner Künzel, Michael Bargende

New vehicle concepts for future business model

Today there are already approximately 950 million passenger cars in use worldwide, tendency rising. This results in severe traffic problems: traffic jams, parking space problems, and extreme air pollution. Because urban areas are especially affected, cities around the world react with action plans. “Low emission zones”, “urban road tolls”, or even the total ban of specific vehicle types are being established to keep private, but also commercial vehicles out of the city centers.

Horst E. Friedrich, Christian Ulrich, Stephan Schmid

UNICARagil – New architectures for disruptive vehicle concepts

This paper provides an overview of the research topics of the UNICARagil project with the focus on different architectures, such as the mechatronic, the software, and the mechanic architecture. The main research questions as well as possible solutions, which will be investigated in this project, are described. The project is funded by the Federal Ministry of Education and Research of GermanyIn terms of the mechatronic and the software architecture, this paper focuses on the ECU concept: the main tasks of the automated driving process are executed on three ECUs, which are called the cerebrum, the brainstem and the spinal cord. This architecture supports the modular approach regarding functional safety, the ability of future updates and upgrades, and the service orientated architecture (SOA) of the software. The well-known SOA approach is transferred to automotive applications and becomes the automotive service orientated architecture (ASOA).Furthermore, the mechanic structure of the four vehicles AUTOtaxi, AUTOelfe, AUTOliefer and AUTOshuttle is described.

Dan Keilhoff, Dennis Niedballa, Hans-Christian Reuss, Michael Buchholz, Fabian Gies, Klaus Dietmayer, Martin Lauer, Christoph Stiller, Stefan Ackermann, Hermann Winner, Alexandru Kampmann, Bassam Alrifaee, Stefan Kowalewski, Fabian Klein, Michael Struth, Timo Woopen, Lutz Eckstein

New vehicle concepts for mobile vacation

Today recreational vehicles (RVs) - Motor caravans and caravans - are mainly based on standard light commercial vehicles and standard trailer chassis. All RVs are designed to deliver the most possible space and ergonomic for a comfort living inside, thus leading to a big and bulky outside.

Rüdiger Freimann, Udo Gillich, Gerhard Gumpoltsberger, Ria Kaiser

RDE-thermal management – From road to rig

Seit Beginn der RDE-Gesetzgebung besteht der Wunsch, zumindest einen Teil der für Entwicklung und Kalibrierung erforderlichen Straßentests auf den Prüfstand zu verlagern. Dazu muss allerdings nicht nur die heute schon weitgehend optimierte Simulation von Last und Drehzahl, sondern auch die thermische Bedingung von Straße und Prüfstand übereinstimmen. Vor allem bei den instationären Vorgängen kommt es hier bei üblichen Prüfstandskonfigurationen zu gravierenden Abweichungen im Emissionsverhalten. Hinzu kommt, dass neuerdings statt konventionellen Thermostaten sog. Thermalmanagement-Module eingesetzt werden, bei denen sich die Abweichungen verstärkt negativ auswirken. Zur thermischen Konditionierung kann man drei Bereiche unterscheiden: Motorraumdurchströmung Hauptwasserkühler (inkl. Ölkühler) Ladeluftkühler (Luft/Luft oder integrierter LLK) Anhand von umfangreichen Fahrzeug- und Prüfstandmessungen werden für die drei Bereiche zuerst deren Auswirkungen auf das Thermalverhalten und die jeweiligen Anforderungen sowie Grenzen abgeleitet. Danach werden die dazu möglichen verschiedenen Lösungswege beschrieben und über Messergebnisse vergleichend diskutiert bzw. bewertet. Von besonderem Neuigkeitswert sind Messungen mit einem „Thermo.Lab“ – Fahrzeug, die Analyse der thermalen Verhältnisse am Prüfstand und die Vorstellung einer völlig neuartigen modellgestützten Konditioniereinheit „Dynamik Modul II“.

Christian Beidl, Johannes Hipp, Günter Hohenberg, Stefan Geneder

Further optimization of NOx emissions under the EU 6d regulation

The first stage of the regulations on real-driving emissions (RDE) became effective in Europe in September 2017. Since then compliance with the EU6d_temp stage has been required in order obtain a type approval. Due to the broad-based use of particulate filters the residual emissions from diesel cars represent only a very small share of inner-city particulate-matter air pollution. For this reason, further development activities on diesel powertrains are now geared towards effectively limiting nitrogen-oxide emissions.

Michael Krüger, Stefan Bareiss, Andreas Kufferath, Dirk Naber, Daniel Ruff, Herbert Schumacher

Developing GDI engines for minimum particle emissions in RDE test conditions

How to identify situations in need of improvement and how to find correct actions to reduce PN emissions in real drive conditions?The engine development procedures include selection of best injectors at the very early stage of hardware definition, and, along the way of combustion system development, the adjustment of injection parameters to the boundary conditions given by stationary and transient engine operation modes until the final vehicle certification in today’s WLTP or future RDE test modes.The overall task: fuel injection for each combustion cycle must result in premixed combustion of a homogenous, stoichiometric charge. On this background the paper describes Selection of injectors for given combustion chamber geometry and in-cylinder flow: test procedures and selection criteria include sub-zero cold start, catalyst heating and part load / high load operation at low and moderate engine speed. Calibration of injection parameters in dynamic drive situations Identification and improvement of PN emission issues in WLTP / RDE test cycles Evaluation of injector coking issues Test methods include the cycle by cycle analysis of spray and flame signals, either recorded with high speed cameras or with fiber optic flame sensors together with cylinder pressure analysis in order to visually see diffusion flame (soot) areas or to identify them by means of their flame radiation signature. These cycle and deg CA resolved combustion signals are related to engine out particle emissions.We present a methodology to effectively use such in-cylinder diagnostics to finally meet target PN emissions levels in a vehicle’s certification test.

A. Hirsch, A. Hochnetz, M. Kortschak, E. Winklhofer

Functional architecture and E/E-Architecture – A challenge for the automotive industry

In upcoming years, the complexity of vehicle function systems will dramatically increase. This increase will have a significant impact on efforts for development, release and maintenance. Especially the domains of Autonomous Driving (AD) and connectivity will drive the increase of functionality.

Detlef Zerfowski, Andreas Lock

Integrated avionics architectures

Reinhard Reichel

Dedicated hybrid powertrain (DHP) – Hybrid concept based on a holistic system approach

Joerg Gindele, Manuel Diehl

Experimental investigations on ICE direct start for hybrid powertrains

Due to heave the most powertrain efficiency and carbon dioxide emission savings at hybrid powertrains the internal combustion direct start could be highly beneficial. To realize a safe reliability and low emissions there are an exhaust gas residual depletion at engine stopping phase for inflammation enhancement of the time based combustion and an appropriate fuel metering based on accurate charge estimation of oxygen necessary. For investigating this EGR depletion at engine runout there was an optical high speed measuring system in combination with cylinder pressure indication used in a four cylinder test engine with electromechanical camshaft phasers. After constructing a proper analysis method there were three strategies investigated, which include actuating throttle and camshaft phasing at engine stopping and oscillation phase before standstill, and compared with each other in the matters of EGR depletion, cylinder charge, engine speed deviation (representing NVH) and crankshaft positioning potential.

Thomas Pausch, Guido Vent, Normann Freisinger, Hardy Weymann, Roland Baar

Extended engine-in-the-loop simulation for development of HEV energy management strategies

Development and evaluation of energy management strategies (EMS) for hybrid electric vehicles (HEV) in early development phases is challenging. For precise analysis at this early stage, internal combustion engine (ICE) operation has to be reproduced as close as possible to its future in-vehicle use. This paper describes the development of an Engine-in-the-Loop (EIL) system as a tool for research of advanced HEV EMS.

Bastian Beyfuss, Peter Hofmann, Bernhard Geringer, Philipp Grassl

Using of an electrochemical compressor for hydrogen recirculation in fuel cell vehicles

The electrochemical compressor is a new and promising technology of hydrogen circulation in fuel cell vehicles. With its almost isothermal operation, modular design and high efficiency compared to mechanical compressors, the device can operate very efficiently with low space requirement.

Wilhelm Wiebe, Sven Schmitz

Development of electric drive concepts for fuel cell vehicles for Germany and China

Regarding the electrification of powertrain in the recent years, different ways seem to be possible. The diversity of drive systems and their topologies are increasing permanently. Even the differences between various markets are remarkable and influence the way of developing technical solutions as well as the mix of technologies in market.

Katharina Bause, Adrian Braumandl, Alexander Stephan, Qiwen Xiao, Matthias Behrendt

Test cell adaptation from engine to fuel cell development

The automotive industry is changing. While in the past individual mobility, performance and speed have been focused on, sustainability, digitalization and connectivity are now the main topics of development. Driving factors are, inter alia, the Paris Agreement on Climate Change, the Dieselgate and related ban on vehicles in cities as well as electric car quotas in China.

Henning Münstermann, Jürgen Knust, Jörg Fischer

Safety assessment of autonomous and connected vehicles by a model-based traffic simulation framework

Safety analysis is an important topic in many different domains in engineering. One of the most important areas where safety assessment plays a major role is the autonomous driving. As a safety-critical domain, the automotive sector heavily needs the tools and techniques to assess the safety level in design phases.

Mustafa Saraoğlu, Andrey Morozov, Klaus Janschek

Identifying relevant traffic situations based on human decision making

The growing complexity of future driving systems and the shorter development cycles pose huge challenges in developing and validating automated driving functions. User expectations and respective requirements must be fully described in detail to enable a complete specification of the target system and deriving test cases for the validation process. The goal of automated driving functions is to assume the driving task not only in specific situations as driver assistance systems, but to handle all upcoming situations in a defined traffic environment.

Christoph Sippl, Florian Bock, Bernd Huber, Anatoli Djanatliev, Reinhard German

Test in applications with regulatory requirements on the example of WLTP

Jan Daniel Jacob

Chances of the digitalization in the test field for operations and product development

„Connected, Autonomous, Shared, Electric: Each one of these points has the potential to turn our industry upside down. The real revolution however lies in the connection of all of these“

Roland Strixner

New energies test facilities – Solutions for a sustainable future

The automotive industry is changing. While in the past individual mobility, performance and speed have been the focus, sustainability, digitalization and connectivity are now the main topics of development. Driving factors are, inter alia, the Paris Agreement on Climate Change, the Dieselgate and related ban on vehicles in cities as well as electric car quotas in China. In the course of the development of sustainable drive technologies we generally speak of “New Energies”.

Gregor Zemitzsch, Jörg Fischer, Edwin Heimberg, Thomas Ille, Stefan Zemitzsch

The new Touareg – Innovision on 4 wheels

The new Touareg – a Volkswagen is making its debut which achieves a new and higher zenith of perfection. The flagship of the brand is equipped with the connectivity of a new era and a pioneering fusion of assistance, comfort, lighting and infotainment systems. In addition, the new Touareg is charging up the market segment of large SUVs with its pure design dynamism.

Stefan Gies

The aerodynamics development of the new Mercedes-Benz GLE

The new Mercedes-Benz GLE, a premium sport utility vehicle (SUV) now in the 4th generation, enters the market with a remarkable drag coefficient of cD= 0.29. The paper shows the history of the drag figures from the first Mercedes-Benz ML from 1997 to the newest model. Furthermore, insights on the development steps are presented. A description of the measures on the exterior and the underbody, which lead to the best-inclass aerodynamic targets for the new off-roader, closes the paper.

Etienne Pudell

Aerodynamics of the new Porsche 911 Carrera

The new Porsche 911 Carrera is characterised by a greater aerodynamic differentiation between efficiency and performance in comparison with its predecessor.In the new Porsche wind tunnel, the aerodynamic drag coefficient of the 911 Carrera was further reduced through optimisation of the basic shape and newly developed measures for improving the underbody flow characteristics.Depending on driving mode and speed, the requirements for minimum driving resistance and high driving-dynamic performance can be met through the control strategy of the active aerodynamic elements at the front and rear of the vehicle.

Bernd Jachowski

Comparing 48V mild hybrid concepts using a hybrid-simulation-toolkit

The automotive sector is undergoing significant changes. Most of those are driven by stricter legislation and higher sensitivity of customers to environmental issues. Electrification of the powertrain is one of the key elements for OEMs to meet the strict CO2 emission targets, especially in Europe. A mild hybridization with 48V systems can be a cost-efficient means to reduce CO2 emissions. In addition, a 48V power supply system enables efficient electrification of other components like pumps and the usage of electrified air boosting devices to provide additional benefits.

Anita Bongards, S. Mohon, D. Semenov, W. Wenzel

From virtual to reality – How 48V systems and operating strategies improve Diesel emission

When supporting the Diesel drivetrain by additional electrification it is crucial to define the operating strategy in close interaction with the hardware selection. To enable early frontloading in a phase when testing is not possible a simulation environment is necessary that models not only the single components but also mirrors the interaction of emotor, combustion engine and aftertreatment and also reflects the respective control strategy.To enable a consistent and continuous (conversion-free) system evaluation, starting from very early stages of the development process up to real semi-virtual prototyping, AVL has developed a neutral open integration approach. This platform called AVL CRUISE M is able to numerically correctly connect and simulate a wide variety of model-based and / or real components on a functional level.The resulting functional prototype consists in this case of several, different and modular system simulation models, which have the task on the one hand to characterize the emissions and temperatures of the engine, as well as the correlating efficiency of the aftertreatment and on the other hand to model the vehicle and the hybridized powertrain including a virtual driver.The paper describes the advanced simulation environment and highlights specific use cases during the development of a 48V Mild Hybrid Diesel concept car between AVL List GmbH and Hyundai Motor Europe Technical Center GmbH. Simulation support is essential in order to match the conflicting targets CO2 – Emissions – ageing in a rather complex system.

Hannes Wancura, Michael Weißbäck, Iaponaira Silva de Abreu, Tobias Schäfer, Steffen Lange, Bastian Unterberger, Stefan Hoffmann

Safety and security – Basic vulnerabilities and solutions

Hubert B. Keller

Tool-based development of efficient automotive multi-core systems

Due to increasing demands for computing power by upcoming applications, such as autonomous driving or Car2x, more and more multi-core processors finding their way into electronic control units of the automotive domain. This leads to a paradigm shift from sequential to parallel processing, which creates many challenges in the development of safety-critical embedded multi-core systems.The appropriate deployment of software components on the available cores of the processor is crucial for a good system behavior, especially regarding response times. This paper proposes a tool-based visualization, analysis and validation of the configured AUTOSAR system, that assists in deployment evaluation and optimization. The fundamental prerequisite that enables deployment of software components on multi-core processors is the efficient provision of basic software services to application software on all processor cores. It is described, that this requirement can be met in particular by the master-satellite architecture.The emerging complexity which results from the vast design space of embedded multicore systems shows, that efficient systems can only be developed by integrating specific tools into a toolchain and using suitable software platforms.

Patrick Friederich, Alexander Zeeb

Architecture and independence controller for deep learning in safety critical applications

The market potential of safety critical products using AI is very attractive and Deep Learning Neural Networks (NN) have proven strengths to provide important functionality. This paper describes some of the challenges in arguing safety of systems using Deep Learning NN, especially functional improvement in context of SOTIF (Safety of the Intended Functionality) or other approaches to provide the safety case. An architecture and independence controller is proposed which can be used beneficially to reduce residual risk of functional insufficiencies for Deep Learning NN based systems.

Ulrich Bodenhausen

AI – Challenges in application with bus data in the automotive sector

Artificial Intelligence (AI) is a scientific field which emerged in the 1950s shortly after the introduction of the first electronic and programable computers. Since then, the field has hit many astonishing milestones, like defeating the then world chess champion Garry Kasparow in 1997 (Deep Blue, IBM) or surpassing human abilities in areas like visual object recognition in images (ISBI [1], ICPR [2]). Today it is used widely in many different areas of our daily lives, from autonomous cars and drones to medical expert systems to recommender systems in online shops.

Alexander Faul, Maria Floruß, Felix Pistorius

Use of a criticality metric for assessment of critical traffic situations as part of SePIA

The requirements for a driver driving through a traffic situation increase with the complexity of the infrastructure, the number of participants, their possible actions and the environmental conditions. Thereby, the human being as the controller of the vehicle is normally able to analyze complex situations and to act accordingly.

Matthias Lehmann, Maximilian Bäumler, Günther Prokop, Diana Hamelow

Simulating surrounding traffic for interactive driving simulators

Simulating driving behavior and vehicle interaction is central to the development of automation techniques as well as the study of human drivers. We present an approach of coupling traditional driver simulators with the open source traffic simulator Eclipse SUMO to generate precise surrounding traffic which reacts to the driver behavior and create a variety of traffic scenarios for testing human and automation behavior.

Michael Behrisch, Danny Behnecke, Jan Wegener, Robert Hilbrich

A lifecycle model to support continuous component evolution in embedded automotive systems

Already today, hardware and software versions of embedded automotive components frequently evolve, due to discontinued electronics or fixed software bugs. For example, the average release cycle for new software versions of a vehicle already in production is six months (Guissouma et al. 2018). With agile development methods, continuous integration efforts and over-the-air software updates, this frequency and the amplitude of system alternations is expected to increase.

Lukas Block, Oliver Riedel, Florian Herrmann

Comparing current and future E/EArchitecture trends of commercial vehicles and passenger cars

The major trends of the automotive industry, such as automated driving, connectivity and electrification require the introduction of new technologies and even technology leaps. They are as well influencing vehicle E/E-architectures as a whole. Vehicles become part of cyber-physical systems and centralization is considered as one of the measures to enable innovation and to reduce complexity. High performance vehicle computers are increasingly introduced as central cornerstones of future E/E architectures.

Tenny Benckendorff, Andreas Lapp, Thomas Oexner, Thomas Thiel

Evaluation of competition and virtual rear subframes by means of the data envelopment analysis

Car subframes are relevant for the architecture and highly integrated structural components in the chassis systems. They influence functional effect chains at the overall vehicle level (e.g. driving dynamics, crash, acoustics) and are characterized by a variety of interfaces (e.g. wheel guidance, powertrain, steering, body). The conflict of objectives between the increasing complexity of the development process and the overall modular strategy requires new methods and concepts to design the subframes in their different development stages. This paper presents a method to investigate both existing competition and virtual concept rear subframes with the help of the Data Envelopment Analysis, known from the production economic sector. For this purpose, existing competitive designs are analyzed, classified and assessed. In addition, a method is shown, how virtual subframe concept models can be created, simulated and rated with the Data Envelopment Analysis automatically in a fast and efficient manner. The example evaluations of both investigations serve as a basis for the future design of rear subframes in the concept and early development phase to solve the described conflict of objectives.

Martin Kundla, Thilo Heussner, Xianda Ye, Dieter Schramm

Evaluation of the required accuracy of chassis models in the comfort relevant frequency range by intuitive switching of the level of detail in SimulationX

Within the context of a research project of ESI ITI GmbH in cooperation with the TU Dresden, a modularly structured chassis library for SimulationX is being developed. The data is transferred consistently and user-friendly by using a Parameterization Line consisting of various test benches.The measurements are carried out at component, subsystem and total vehicle level. In addition to geometry and mass data, it is also possible to determine the characteristics of the rubber suspension mounts, for example, which are essential for elastokinematics. Model parameters are determined directly by means of suitable evaluations or by optimization.The chassis library for the construction of the vehicle models contains not only main chassis components such as link, shock absorber and bearing models but also readymade templates for all common axle types as well as model elements for the driver, track and environment. The level of detail of the axles ranges from characteristic curvebased models for driving dynamics to detailed multi-body models that take elastokinematics into account. The level of detail can be changed by just a few clicks. The transfer of the parameters determined on the parameterisation line is performed table- and script-based in a central parameter block, so that the parameterisation is clearly bundled in one place.This procedure ensures that the parameterization is tailored directly to the model structure and valid models are created.

Tom Wiedemann, Claudia Belanger, Felix Kocksch, Kay Büttner

Cause and effect chains analysis of rollover behavior with respect to chassis design

The trends towards increasing popularity of high performance SUVs require a novel assessment of “trade-off” between vehicle dynamics, ride comfort and rollover stability, which represents a new challenge for chassis design. The key to a better consideration of rollover in chassis design is to understand the complicated physical phenomena in the nonlinear dynamic range and to analyze the effect chains from system inputs (such as steering angle and vehicle velocity) towards system outputs (e.g. roll angle, yaw rate and wheel lift behavior).

Fan Chang, Konrad Krauter, Sebastiaan van Putten, Jan Kubenz, Armin Ohletz, Günther Prokop

AC-APU – A hydrogen based A/C-unit for electric vehicles

In this paper a hydrogen-based air-conditioning unit, which can also function as range extender for electric vehicles, is studied. This hydrogen A/C-unit utilizes the endothermic reaction of hydrogen desorption from metal hydrides to generate a cooling effect. Within DLR’s Next Generation Car project a prototype system was developed and characterized on a test bench. This system represents a world’s first proof of concept, where two metal hydride reactors are coupled to a fuel cell to establish a process which provides cooling power without any electrical power input. The measured cooling power is directly coupled to the hydrogen mass flow taken from the reactors, thus being indirectly linked to the fuel cells electrical power output. A maximal heat flow of 0.72 kW was detected at 5 kW electric fuel cell power. The paper concludes with the discussion of an appropriate vehicle integration concept for this innovative technology.

R. Hegner, C. Weckerle, I. Bürger, H. Dittus, M. Schier, H. E. Friedrich

A complete digital engine cooling module catalog for balancing cooling and aerodynamics

Satheesh Kandasamy, C. Chang, T. Yasuda, Y. Yagi, S. Miura

Thermal design of portable power tools with combustion engines and electric motors

The goal of thermal design and optimization – whether for portable power tools with combustion or electric motors – is the thermal protection of the machine to prevent overheating and subsequent damages. To ultimately reach a reliable solution for all requirements, both cases involve diverse restrictions in the design process. With increasingly sophisticated machines that combine the highest performance, minimal weight and compact assembly space, the demands on cooling design continue to grow.

Silke Kaminski, Gordon Groskopf

Lightweight brake rotors with thermally sprayed ceramic coatings as friction surfaces

Rainer Gadow, S. Popa, A. Killinger

Lightweight forging initiative III: Forging technology contribution to lightweight design

When one thinks of forging, “lightweight” is not a word that immediately springs to mind. However, when speaking of “lightweight forging”, what initially appears to be unrelated is in fact, on closer inspection, a cost-efficient approach for achieving considerable lightweighting advances in automotive applications that is suited to large-series production. By exploiting the potential offered by forging technology, it is possible to reduce the mass of a medium-sized vehicle by 42 kg and that of a light commercial vehicle by 99 kg [1, 2].

Hans-Willi Raedt, Thomas Wurm, Alexander Busse

Investigation of interactions between fuels and fuel leading components of plug-in-hybrid electric vehicles

Sustainable energy supply in all consumption segments especially in the transport sector requires the gradual substitution of fossil fuels with renewable fuels. By 2020, 10 % of transport related final energy consumption is to be covered by renewable energies; for the entire energy sector, a share of 20 % renewables has been set as a binding community target for all EU states.

Sebastian Feldhoff, Simon Eiden, Jens Staufenbiel, Anja Singer

Acoustic transmission loss in turbochargers

Internal combustion engines are increasingly being equipped with turbochargers to increase performance and reduce fuel consumption and emissions. Being part of exhaust and intake systems, the turbocharger strongly influences the orifice noise emission. Although 1D-CFD simulations are commonly used for the development of intake and exhaust systems, validated acoustic turbocharger models are not yet state-of-the-art. Additionally, there are only few literature sources on the acoustic influence of the turbocharger. Consequently, the aim is the investigation of the influence on the orifice noise and the development of an accurate model for 1D-CFD simulations.Therefore the acoustic transmission loss was measured for a wide operating range of four turbochargers, including wastegate and VTG-system variations. The applications range from small gasoline engines up to large diesel engines. These investigations reveal that low frequencies for compressors and turbines are dominated by impedance discontinuities, while the upstream transmission loss increases considerably with high mass flows and pressure ratios. Especially for the compressor, high frequencies are determined by destructive interference in the stator. Overall, the turbocharger has a high damping potential.While Aymann’s common simulation approach accurately captures low frequencies, a new generic approach was developed to additionally model high-frequency interferences by linking the stator geometry with potential sources and turbocharger performance maps. In this way, high acoustic and thermodynamic prediction quality could be achieved. This could be proven especially for higher frequencies of the intake orifice noise, where the predicted sound pressure level was corrected by up to 5 dB.The presented newly developed model for 1D-CFD simulations increases the efficiency of the acoustic development process of intake and exhaust systems. The applied measurement approach has great potential to further improve also the model development process of other intake and exhaust system components.

Hendrik Ruppert, Marco Günther, Stefan Pischinger

Potential of air path variabilities for heavy duty Diesel engines

A look at past and current legislation for commercial vehicles indicates a further tightening of future legislation limits. For example, the nitrogen oxide limit values have been reduced from Euro V to Euro VI by 80 %. An “Optional Low NOx Standard” is existing in the USA since 2014. Even though this certification is currently still voluntary, the values show clear tendencies. Compared to the current Euro VI standard, NOX emissions are reduced by further 93%. In addition to the reduction of nitrogen oxide emissions, the reduction of greenhouse gases is also further tightened.

Marius Betz, Dávid Kovács, Peter Eilts

Automated & cloud-based load profile-generation and evaluation of lithium ion batteries

Today lithium ion batteries (LIB) are the state-of-the-art technology for traction batteries in electric vehicles due to their high energy capacity and output as well as power density. However, the determination of the aging and performance of the LIB remains a challenge, since these essential parameters are highly dependent on the vehicle, user behaviour and environmental conditions. Therefore, traction batteries have the necessity to be constantly monitored by the vehicle electronics. In addition, new methods are needed for the efficient evaluation and diagnosis of the LIB, which are used during development, production and subsequent operation.In this paper, a fully automated, cloud-based process is introduced, which includes the measurement of the LIB during operation, the generation of load profiles at cell level and transfer to battery test benches. To determine the load profile, the combination of the driving profile of the vehicle (for example GPS data) with the load acting on the installed LIB cells takes place.With the help of a central cloud-based IT platform, data loggers, battery test stands and Key Performance Indicators (KPIs) for the aging process of LIB are networked to automatically integrate the generated load profiles into laboratory test series, thus enabling efficient and customer - oriented development.Thus, all battery types in the lab can be loaded with the critical load profile of the specific vehicle and user behaviour, the best technology for the intended use can be determined and vehicles with optimized range, charging time and lifetime can be developed.

Alexander Kohs, Thomas Freudenmann, Fabian Back, Mohannad El-Haji, Tobias Schilling, Praveen Kumar Kuppusamy

Requirements for battery enclosures – Design considerations and practical examples

Requirements for battery housings in e-vehicles are extensive: regulatory requirements; functional requirements; consideration of the installation conditions, transformation of forces and torques into the vehicle structure as well as wishes and demands of the end customer for trouble-free operation under a wide variety of climatic conditions.Space and weights are scarce resources in electric vehicles; this means lightweight construction and multifunctionality are stringent requirements for all functional units. The multifunctional battery housing - the B: HOUSE® in GVI® technology - offers new and highly efficient solutions.This concept allows effective passive and active thermal management, vibration and crash-proof housing and fixation of the battery cells/ modules, fire protection in all directions, EMC safety, environmental protection, lightweight construction – which means resource saving and weight-optimization in one functional unit.

Jobst Kerspe, Michael Fischer

Prediction of the lifetime of urban electric bus traction batteries in the context of the overall system design

Driven by the ongoing discussion about clean air in German cities, many municipal transport companies are pushing ahead with the conversion of their bus fleets from diesel buses to electric buses. In many cities, this is an elementary step in the package of measures to reduce emissions and comply with legal limits.

Martin Ufert

The impact of pass-by noise legislation on the design of exhaust systems

In all major markets, the legislation on emissions (CO2, NOx, and PM) has been changed drastically and limit values have been lowered over the last years and will be even lower in the near future. Moreover, the new pass-by noise rules require more testing e.g. for additional sound emissions provisions (ASEP) and limit values are more stringent than ever according to R51.03, particularly with the phase coming into force in 2024. Besides the tire noise, the powertrain and here in particular the exhaust tailpipe noise is nowadays the main contributor to pass-by noise.

Jan Krüger, Peter Wink, Maike Werner

Simulative research on the tire torsional vibration and its vehicle relevant influencing factors

Tire pressure as an important vehicle parameter has a great impact on the vehicle safety, ride comfort, driving dynamics and fuel economy. Every registered vehicle in the USA needs to be equipped with a tire pressure monitoring system from 2007. This legal requirement has been published in the EU since 2012.

Wenrui Han, Yi Guo, Günther Prokop, Thomas Roscher
Weitere Informationen

Premium Partner

    Bildnachweise