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In this work the pre- to main chamber ignition process is studied in a Wärtsilä 34SG spark-ignited lean burn four-stroke large bore optical engine (bore 340 mm) operating on natural gas. Unburnt and burnt gas regions in planar cross-sections of the combustion chamber are identified by means of planar laser induced fluorescence (PLIF) from acetone seeded to the fuel. The emerging jets from the pre-chamber, the ignition process and early flame propagation are studied. Measurements reveal the presence of a significant temporal delay between the occurrence of a pressure difference across the pre-chamber holes and the appearance of hot burnt/burning gases at the nozzle exit. Variations in the delay affect the combustion timing and duration. The combustion rate in the pre-chamber does not influence the jet propagation speed, although it still has an effect on the overall combustion duration.

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.

High-speed OH chemiluminescence imaging is used to measure the lift-off length of diesel sprays in an optical heavy-duty diesel engine of 2 L displacement operated at 1200 rpm and 5 bar IMEP. Stereoscopic images are acquired at two different wavelengths (310 and 330 nm). Subtraction of pairwise images helps reducing the background coming from natural soot incandescence in the OH chemiluminescence images. Intake air temperature (343 to 403 K), motored top dead center density (18 to 22 kg/m3), fuel injection pressure (150 to 250 MPa), intake oxygen concentration (17 to 21 %vol) and nozzle diameter (0.1 and 0.14 mm) are varied and a nonlinear regression model is derived from the experimental results to describe stabilized lift-off length as function of the experimental factors. The lift-off length follows the general trends that are known from spray vessel investigations, but the strength of the dependence on certain variables deviates strongly from those studies.

The influence of jet-flow and jet-jet interactions on the lift-off length of diesel jets are investigated in an optically accessible heavy-duty diesel engine. High-speed OH chemiluminescence imaging technique is employed to capture the transient evolution of the lift-off length up to its stabilization. The engine is operated at 1200 rpm and at a constant load of 5 bar IMEP. Decreasing the inter-jet spacing shortens the liftoff length of the jet. A strong interaction is also observed between the bulk in-cylinder gas temperature and the inter-jet spacing. The in-cylinder swirl level only has a limited influence on the final lift-off length position. Increasing the inter-jet spacing is found to reduce the magnitude of the cycle-to-cycle variations of the lift-off length.

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.

The number of vehicles in use is increasing from year to year. It causes more fuel/energy to be consumed, and more carbon dioxide or other exhaust gases are released to the environment. But the legislations on carbon dioxide emissions have become stricter than before. In the overall effort to achieve sustainability, advanced technological solutions have to be developed to reduce fuel consumption and carbon dioxide emissions from vehicles. More than half of the energy in vehicles is lost as heat to the different cooling systems (engine cooling system, air conditioning, frictional components cooling) and exhaust gas. Reducing the amount of energy lost in vehicle cooling systems will enhance the fuel efficiency of the vehicles. This paper presents a literature survey of different cooling systems in vehicles, which includes the engine cooling system, air conditioning of the compartment, the electronic cooling system and cooling of frictionally heated parts.

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.

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.

In this study, an investigation was made on a heavy duty diesel engine using both conventional diesel combustion mode and a partially premixed combustion (PPC) mode. A segment mesh was built up and modeled using the commercial CFD code AVL FIRE, where only the closed volume cycle, between IVC and EVO, was modeled. Both combustion modes were validated using experimental data, before a number of heat flux boundary conditions were applied. These conditions were used to evaluate the engine response in terms of engine performance and emission levels for the different percentage of heat rejection. The engine performance was measured in terms of specific fuel consumption and estimated power output, while the calculated net soot and accumulated NOx mass fractions were used for comparing the emission levels. The results showed improved efficiency for both combustion types, but only the PPC combustion mode managed that without increasing the production of NOx emissions severely.

This study investigates mode switching from spark ignited operation with early intake valve closing to residual gas enhanced HCCI using negative valve overlap on a port-fuel injected light-duty diesel engine. A mode switch is demonstrated at 3.5 bar IMEPnet and 1500 rpm. Valve timings and fuel amount have to be selected carefully prior to the mode switch. During mode transition, IMEPnet deviates by up to 0.5 bar from the set point. The time required to return to the set point as well as the transient behavior of the engine load varies depending on which control structure that is used. Both a model-based controller and a PI control approach were implemented and evaluated in experiments. The controllers were active in HCCI mode. The model-based controller achieved a smoother transition and while using it, the transition could be accomplished within three engine cycles.

A detailed investigation is made of the impact of mechanical deformation on the in-cylinder volume as function of crank angle degree in an optical engine of Bowditch design. The squish height is found to change linearly with mass and pressure forces. It increases due to pressure forces and decreases due to mass forces. The thermal forces have an impact on the squish height but it is not clear in what direction. The volume change caused by deformations did not change the calculated load significantly but gave errors during heat release calculations. Two different strategies to reduce these errors are presented.

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.

Trends in today's and future embedded powertrain systems show a strongly growing demand of communication between the functional units inside a car. A cost optimized system partitioning leads to several independent building blocks that have to be interconnected. Depending on the task of each building block, different classes of data exchange can be distinguished, differing in the required bandwidth, the tolerated latency and speed for real time critical tasks. In order to minimize the communication effort concerning time, chip size and overall costs, different communication requirements have been analyzed. The results lead to improvements of standard serial interfaces by application-oriented features.