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Future automotive systems will be connected with other vehicles and information systems for improved road safety, mobility and comfort. This new connectivity establishes data and command channels between the internal automotive system and arbitrary external entities. One significant issue of this paradigm shift is that formerly closed automotive systems now become open systems that can be maliciously influenced through their communication interfaces. This introduces a new class of security challenges for automotive design. It also indirectly impacts the safety mechanisms that rely on a closed-world assumption for the vehicle. We present a new security analysis approach that helps to identify and prioritize security issues in automotive architectures. The methodology incorporates a new threat classification for data flows in connected vehicle systems.

In this paper, we propose a hardware and a software design method considering functional safety for an electro-mechanical brake (EMB) control system which is used as a brake actuator in a brake-by-wire (BBW) system. A BBW system is usually composed of electro-mechanical calipers, a pedal simulator, and a control system. This simple by-wire structure eliminates the majority of bulky hydraulic brake devices such as boosters and master cylinders. The other benefit of a BBW system is its direct and independent response; this leads to enhanced controllability, thus resulting in not only improved basic braking performance but also considerably easier cooperative regenerative braking in hybrid, fuel-cell, and electric cars. The importance of a functional safety based approach to EMB electronic control unit (ECU) design has been emphasized because of its safety critical functions, which are executed with the aid of many electric actuators, sensors, and application software.

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.

Wheels on passenger vehicles cause about 25% of the aerodynamic drag. The interference of rims and tires in combination with the rotation result in strongly turbulent wake regions with complex flow phenomena. These wake structures interact with the flow around the vehicle. To understand the wake structures of wheels and their impact on the aerodynamic drag of the vehicle, the complexity was reduced by investigating a standalone tire in the wind tunnel. The wake region behind the wheel is investigated via Particle Image Velocimetry (PIV). The average flow field behind the investigated wheels is captured with this method and offers insight into the flow field. The investigation of the wake region allows for the connection of changes in the flow field to the change of tires and rims. Due to increased calculation performance, sophisticated computational fluid dynamics (CFD) simulations can capture detailed geometries like the tire tread and the movement of the rim.

Hybrid vehicle simulation methods combine physical test articles (vehicles, suspensions, etc.) with complementary virtual vehicle components and virtual road and driver inputs to simulate the actual vehicle operating environment. Using appropriate components, hybrid simulation offers the possibility to develop more accurate physical tests earlier, and at lower cost, than possible with conventional test methods. MTS Systems has developed Hybrid System Response Convergence (HSRC), a hybrid simulation method that can utilize existing durability test systems and detailed non-real-time virtual component models to create an accurate full-vehicle simulation test without requiring road load data acquisition. MTS Systems and Audi AG have recently completed a joint evaluation project for the HSRC hybrid simulation method using an MTS 329 road simulator at the Audi facility in Ingolstadt, Germany.

FlexRay1 is a high speed, time triggered and fault tolerant communication protocol, which was specified to meet the requirements of safety-critical automotive applications. The achieved maturity of FlexRay encourages the implementation on silicon. The CIC-3102 device is a standalone controller provided by Infineon Technologies. It runs the wide spread E-Ray3 IP from Bosch. A complete communication node for FlexRay requires additional devices for the physical layer and the application part. The CIC-310 can communicate with a host controller via three different interfaces micro link interface MLI, serial synchronous interface SSC, external bus XMU. Its physical layer interface corresponds to the FlexRay specification. The CIC-310 provides features like intelligent move engines to maximize the achievable data rate as well as to minimize the workload of the host. Therefore, the CIC-310 allows a very flexible and efficient way to build and operate FlexRay nodes.

As the automotive industry quickly moves towards hybridized and electrified vehicles, the optimal integration of power electronics in these vehicles will have a significant impact not only on the cost, performance, reliability, and durability; but ultimately on customer acceptance and market success of these technologies. If properly executed with the right cost, performance, reliability and durability, then both the industry and the consumer will benefit. It is because of these interdependencies that the pace and scale of success, will hinge on effective collaboration. This collaboration will be built around the convergence of automotive and industrial technology. Where real time embedded controls mixes with high power and voltage levels. The industry has already seen several successful collaborations adapting power electronics to the automotive space in target vehicles.

It is the beginning of a new age: multicore technology from the PC desktop market is now also hitting the automotive domain after several years of maturation. New microcontrollers with two or more main processing cores have been announced to provide the next step change in available computing power while keeping costs and power consumption at a reasonable level. These new multicore devices should not be confused with the specialized safety microcontrollers using two redundant cores to detect possible hardware failures which are already available. Nor should they be confused with the heterogeneous multicore solutions employing an additional support core to offload a single main processing core from real-time tasks (e.g. handling peripherals).

Braking systems require a high system safety level: New safety concepts need to be implemented by reducing the system complexity. Microcontrollers with special safety functions are available with implemented features, self detecting and compensating different types of faults. Today usually two microcontrollers are used to check each other. Power devices provide microcontroller supplies and drive motors and valves; internally the functions are supervised to avoid incorrect system behaviour due to wrong voltages, currents, missing loads or other malfunctions. Bus interfaces, signal conditioning and interfaces for high voltage signals are integrated into the power system ICs. Latest BIPOLAR-CMOS-DMOS power technologies enable the power semiconductors to integrate logic functions.

Electronic throttle systems are becoming more and more important in today's motor vehicles. These systems consist of: a throttle valve with an electrical actuator and a transmission a position feedback an electronic acceleration pedal an electronic control unit (ECU) a semiconductor h-bridge for driving the motor. The electronic acceleration pedal gives a set point to the ECU. A control signal is generated and moves the motor of the throttle valve with a semiconductor h-bridge to the requested position. The voltage drop of a potentiometer is used here as control feedback signal. The potentiometer in the throttle valve is moved very often and has a rough environment like high temperature and vibrations. Therefore this system has a lot of problems with mechanical attrition and reliability during the whole system lifetime. The accuracy of the position control decreases over time.

Modern semiconductor devices enable highly efficient conversion of electrical power. Together with the microcontroller, they are the key elements for generation of the alternating currents from the car's DC supply that are necessary to drive high-performance units such as starter-alternators. These allow the combustion engine to crank up in several 100 ms and deliver up to 15 kW of electrical power. Smart driver ICs such as the TLE6280 enable the fast development of the interface between the microcontroller and the power switches. Currents of some 100A can be handled with the new OptiMOS FETs. Their rugged and ultra-low ohmic technology and their innovative packaging concepts, such as Power Modules and Power-Bonded MOSFETs, allow the building of compact and efficient control units.

Today's body and convenience applications in general directly control actuators and sensors from a single central electronic control unit (ECU). Future systems will be made of subsystem-clusters communicating via a local Class/A communication bus. This enables modular system design to reduce system complexity. For these types of new distributed applications the LIN bus is currently the most promising communication protocol. To allow a seamless migration from existing centralized to these next generation clustered system developers require software and hardware products for a homogenous and transparent LIN bus communication.

The aim of this paper is to compile the state of the art of engine control and develop scenarios for improvements in a number of applications of engine control where the pace of technology change is at its most marked. The first application is control of downsized engines with enhancement of combustion using direct injection, variable valve actuation and turbo charging. The second application is electrification of the powertrain with its impact on engine control. Various architectures are explored such as micro, mild, full hybrid and range extenders. The third application is exhaust gas after-treatment, with a focus on the trade-off between engine and after-treatment control. The fourth application is implementation of powertrain control systems, hardware, software, methods, and tools. The paper summarizes several examples where the performance depends on the availability of control systems for automotive applications.

Vehicle Security means protecting potential threats, unintended malfunction and illegal tuning. In addition, it has become a more important issue on an automotive system as it is directly connected to the driver and pedestrian's life. Automotive industry significantly needs to enhance security policies to prevent attacks from hackers. Nevertheless, in some systems, performance still has to be considered at first when security functions are implemented. Especially, in case of Engine Management System (EMS), fast engine synchronization for starting should be considered as the first priority. This paper is intended to show an approach to design efficient secure boot implementation for EMS. At the beginning of this paper, the concept of secure boot is explained and several use cases are introduced according to execution modes, such as the foreground and background secure boot modes. As a next step, engine starting process by EMS is explained.

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 automotive industry is moving from fossil carburant to electric drive trains due to the stringent CO2 reduction policies. In this context, the electric energy storage becomes one of the key parameters of successful rolling out electrified vehicles. Typical battery management systems comprises of battery cells measurement and monitoring, balancing function, temperature monitoring, together with the State of Charge and State of Health estimations based on the given measurements. Together with the functions above, a robust internal IC communication protocol is one of the key parameters to guarantee battery performance as well as safety. This paper focuses on the automotive battery communication system. On one side, the importance of the communication system and its impact in the EDT (electric drive train) is discussed including safety aspects. Later on, the different communication methods up to date are analyzed to further understand their limitations.

The migration of many vehicle security features from mechanical solutions (lock and key) to electronic-based systems (transponder and RF transceiver) has led to the need for purely electrically operated locking mechanisms. One such example is a steering column lock, which locks and unlocks the steering wheel movement via a reversible electric motor. The safety case for this system (in respect to ISO26262) is highly complex, as there is no single safe state of the steering column lock hardware because there is a wider system-level interlock required. The employed control platform uses ASIL D capable multicore microcontroller hardware, together with the first implementation of AutoSAR® version 4.0 operating system to demonstrate a real-world usage of the newly specified encapsulation and monitoring mechanisms using the multicore extensions of AutoSAR and those of PharOS.

Electric vehicles differ from conventionally powered vehicles in terms of many characteristics that are directly relevant to the customer. The most evident ones are the total driving range, which is limited by the battery capacity, and the different acceleration behavior, which is directly influenced by the electric motor's torque characteristics. Furthermore, there are many other vehicle characteristics, such as lateral dynamics, that are also strongly influenced by electrification. For all customer-relevant vehicle characteristics, it is important to know the necessary and optimal fulfillments in order to plan and evaluate new electrified vehicle concepts. Correlation functions can be used to convert values for technical characteristics to normalized customer satisfaction fulfillments. To evaluate the quality of a vehicle concept during the development process, a parametric cost function is defined.

To significantly increase fuel efficiency while keeping power and performance of its signature S models, AUDI developed a new 4.0 TFSI engine with Cylinder on Demand technology and introduced it with its new S6, S7 and S8 models. To manage upcoming NVH issues due to this new technology and keep the intended sporty V8 note of the engine under all operating conditions, a broad range of new and advanced technologies was introduced with these vehicles. This paper focusses on the Active Noise Control system and its development. It describes the ANC system from a control theory perspective in addition to the acoustical perspective. Special features of the system include the availability of multiple tunings (4/8 cylinder mode) to support the specific overall sound character and the fast switching process as switching between different cylinder configurations might be as fast as 300 ms. In addition, the system also includes specific features that allow an advanced audio system diagnosis.

In current research projects such as "Vehicle to Grid" (V2G), "Vehicle to Building" (V2B) or "Vehicle to Home" (V2H), plug-in vehicles are integrated into stationary energy systems. V2B or V2H therefore stands for intelligent networking between vehicles and buildings. However, in these projects the objective is mostly from a pure electric point of view, to smooth the load profile on a household level by optimized charging and discharging of electric vehicles. In the present paper a small energy system of this kind, consisting of a building and a vehicle, is investigated from a holistic point of view. Thermal as well as electrical system components are taken into account and there is a focus on reduction of overall energy consumption and CO₂ emissions. A predictive energy management is presented that coordinates the integration of a plug-in hybrid electric vehicle into the energy systems of a building. System operation is optimized in terms of energy consumption and CO₂ emissions.