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To satisfy the increasing demand for automotive safety a warning system (WARN) to support drivers has been developed. The basic idea is to transmit safety-related information from one vehicle to surrounding vehicles by direct wireless communication. To ensure user-acceptance of the system different strategies have been developed in order to provide only relevant information to a specific driver. The strategies rely on a comparison of the received alert messages with the current driving situation. Simulations show a significant safety-improvement due to the system if at least 10 percent of all vehicles are equipped with the system.

In studying H2S emissions, it is desirable to have an analytical technique which is rapid, continuous, accurate and easy to use in a laboratory or vehicle exhaust environment. Typically, H2S has been measured using the EPA impinger method with collection times on the order of 1 to 2 minutes. Other techniques have been developed with significantly shorter response times. However, it has been shown that the major release of H2S occurs in less than 20 seconds after a vehicle changes from rich to lean operation. Therefore, it is highly desirable to have an H2S analytical technique with a response time of less than 10 seconds. In this paper, the benefits of use of a chemical ionization mass spectrometer (CIMS) to continuously monitor H2S and SO2, emissions are reported. Using the CIMS technique, the effects of several operating parameters on the release of H2S and SO2 from automotive catalysts were studied.

The potential to reduce the cost of embedded software by standardizing the application behavior for Automotive Body and Comfort domain functions is explored in this paper. AUTOSAR, with its layered architecture and a standard definition of the interfaces for Body and Comfort application functions, has simplified the exchangeability of software components. A further step is to standardize the application behavior, by developing standard specifications for common Body and Comfort functions. The corresponding software components can be freely exchanged between different OEM/Tier-1 users, even if developed independently by multiple suppliers. In practice, individual OEM users may need to maintain some distinction in the functionality. A method of categorizing the specifications as ‘common’ and ‘unique’, and to configure them for individual applications is proposed. This allows feature variability by means of relatively simple adapter functions.

The air conditioning system is becoming more and more a competitive issue, moving from optional to standard vehicle equipment. Therefore, also thermal comfort level is moving from simple air temperature measurement to a more systemic approach, where the contribution of every element of the car cabin has to be taken in account. Improving contact thermal sensation with the seat is one of the main issues to improve overall thermal comfort in transportation. A method has been defined to assess the perceived thermal quality of seats taking into account the sweating human thermoregulatory process. The method is based on a thermal manikin representing a torso able to simulate in a portion of the back the sweating phenomena. The first part of the paper is focused on the instrument and developed measuring method description. The second part is dedicated to detail the correlation between experimental measurements and subjective quality index obtained during an extensive on-road panel test.

In this paper, the invisible hand concept for the definition of Advanced Driver Assistant Systems (ADAS) Human Machine Interfaces (HMI) is introduced. The main idea is that these systems become a sort of "invisible hand'' able to support the driver and to increase driving safety if they are integrated with each other (i.e., longitudinal, lateral and rear control) and the most "persuasive'' and "efficient'' interaction between driver and ADA systems is developed. Here the analysis is conducted taking into consideration the technological evolution scenario and the identification of related user interaction aspects (including technical and communication analysis). Moreover, the ways to design the best interaction between drivers and ADAS interfaces from communication and HMI points of view has been included as well as an overview of the user centered approach adopted in the Centro Ricerche Fiat's design process.

The cabin comfort is one of the most competitive issues in the automotive area of business. The thermal comfort and the environmental well-being are fundamental performances that contribute to generate the more general idea of perceived quality. The CRF developed in the past the concept so-called “healthy bubble” that was implemented in the Lancia Dialogos concept car. The passengers are surrounded by an air bubble, created by generating low velocity air flows, that are diffused through the interior panels and components (e.g. dashboard, roof, back of the seats, etc.), and by surfaces temperature control (e.g. carpet, seats, etc.). At present the original idea has generally been accepted, and different solutions to diffuse air and to control surface temperature of vehicle interiors have been proposed by some automotive supplier.

Due to an earlier analysis of the interrelation between collisions and advanced driver reaction a significant number of accidents could be avoided through timely threat recognition and appropriate maneuvers for collision avoidance. This may be achieved either by suitable warning to the driver or by automatic support to longitudinal or lateral control of the vehicle. A precondition for the registration of the dangerous situation is the incorporation of appropriate sensors. This leads to an surround sensor vision system accompanied by a matched human machine interface. Many vehicles readily offer ultrasonic reversing aids as add-on systems. Furthermore, long-range radar systems for adaptive cruise control are now coming on the market. New sensor technologies, such as short-range radar and video, which are currently under development, open up a plurality of novel functions thus enhancing driving safety and comfort.

Seatbelt retractors as important part of modern safety systems are mounted in any automotive vehicle. Their internal locking mechanism is based on mechanically sensing elements. When the vehicle is run over rough road tracks, the retractor oscillates by spatial mode shapes and its interior components are subjected to vibrations in all 6 degrees of freedoms (DOF). Functional backlash of sensing elements cause impacts with neighbouring parts and leads to weak, but persistent rattle sound, being often rated acoustically annoying in the vehicle. Current acoustic retractor bench tests use exclusively uni-directional excitations. Therefore, a silent 2 DOF test bench is developed to investigate the effect of multi-dimensional excitation on retractor acoustics, combining two slip-tables, each driven independently by a shaker. Tests on this prototype test bench show, that cross coupling between the two perpendicular directions is less than 1%, allowing to control both directions independently.

A closure system for automotive security and driver comfort has been developed. The system combines a passive entry system and an electronic door latch system. The passive entry system utilises a single chip transponder for vehicle immobilisation, passive entry and remote control functionality. The form factor free transponder enables the integration into a key fob or a smart card. The system can be activated by either pulling the door handle or by using a push button transponder. Due to the inductive coupling between the transponder and the vehicle mounted antennas, the vehicle door or trunk opens on successful verification as if there were no locks. Additionally, inside the vehicle, the transponder can be used as a far range immobiliser. The electronic door latch system utilises electronically controlled latches.

In spite of improvements in passive safety and efforts to alter driver behavior, the absolute number of highway fatalities in 2002 increased to the highest level since 1990 in the US. ESP is an active safety technology that assists the driver to keep the vehicle on the intended path and thereby helps to prevent accidents. ESP is especially effective in keeping the vehicle on the road and mitigating rollover accidents which account for over 1/3 of all fatalities in single vehicle accidents. In 1995 Bosch was the first supplier to introduce electronic stability control (ESC) for the Mercedes-Benz S-Class sedan. Since then, Bosch has produced more than 10 million systems worldwide which are marketed as ESP - Electronic Stability Program. In this report Bosch will present ESP contributions to active safety and the required adaptations to support four wheel driven vehicles and to mitigate rollover situations.

Nowadays, a continually growing system complexity due to the development of an increasing number of vehicle concepts in a steadily decreasing development time forces the engineering departments in the automotive industry to a deepened system understanding. The virtual design and validation of individual components from subsystems up to full vehicles becomes an even more significant role. As an answer to the challenge of reducing complete hardware prototypes, the virtual competence in NVH, among other methods, has been improved significantly in the last years. At first, the virtual design and validation of objectified phenomena in analogy to hardware tests via standardized test rigs, e.g. four poster test rig, have been conceived and validated with the so called MBS (Multi Body Systems).

A major trend in modern vehicle control is the increase of complexity and interaction of formerly autonomous systems. In order to manage the resulting network of more and more integrated (sub)systems Bosch has developed an open architecture called CARTRONIC for structuring the entire vehicle control system. Structuring the system in functionally independent components improves modular software development and allows the integration of new elements such as integrated starter/generator and the implementation of advanced control concepts as drive train management. This approach leads to an open structure on a high level for the design of advanced vehicle control systems. The paper describes the integration of the spark-ignition (SI) engine management system (EMS) into a CARTRONIC conform vehicle coordination requiring a new standard interface between the vehicle coordination and the EMS level.

Vibration testing is often carried out for automotive components to meet guidelines based on their operational environments. This is an iterative process wherein design changes may need to be made depending on an intermediate model’s dynamic behavior. Predicting the behavior based on modifications in boundary conditions of a well-defined numerical model imparts practical insights to the component’s responses. To this end, application of a general method using experimental free-free condition frequency response functions of a structure is discussed in the presented work. The procedure is shown to be useful for prediction of responses when kinematic boundary conditions are applied, without the need for an actual measurement. This approach is outlined in the paper and is applied to datasets where dynamic modifications are made at multiple boundary nodes.

The aim of the project is to reliably identify the set of constructive features responsible for the highest noise levels in the interior of motor vehicles. A simulation environment based on artificial intelligence techniques such as neural networks and genetic algorithms has been implemented. We used a system identification approach in order to approximate the functional relationship between the target noise series and the sets of constructive parameters corresponding to the cars. The noise levels were measured with a microphone positioned on the driver''s chair, and corresponded to a variation of the engine rotation of 600-900 rot/min. The database includes 45 different cars, each described by vectors of 67 constructive features.

Despite the tough environmental conditions facing electronic systems in commercial vehicles, electronics is gaining ground also in these applications. In the drive sector it improves the operation of the main and auxiliary drives, upgrades fuel efficiency and reduces emission pollutant levels. It enhances safety by preventing wheel spinning in braking and acceleration. Electronic displays reduce the number of single indications otherwise needed, thus making for more clarity in information for the driver and facilitating the driver's task. Self-diagnosing and integrated emergency operation (“limp home”) capabilities are to ensure availability, a factor of special importance in commercial vehicles. A data interface standardized as widely as possible would allow add-on systems to be coupled easily and flexibly.

Since introduction of safety belts in the 70s and airbags in the early 80s, these passive safety technologies have become standard in many markets. Remarkable improvement in passive safety, efforts to alter driver behaviour and infrastructural programmes have led to substantial reductions of fatalities in many regions, although the absolute number of highway fatalities increased e.g. in the USA in 2002 to the highest level since 1990. Electronic Stability Control (ESC) as an active safety technology assists the driver to keep the vehicle on the intended track and thereby actively prevents accidents. In 1995 Bosch was the first supplier to introduce ESC for the Mercedes-Benz S-Class, where it is marketed as ESP® - Electronic Stability Program. Since then, Bosch has produced more than 30 million systems worldwide. Many studies have now confirmed that ESC can prevent a vehicle from skidding or rolling over in nearly all driving situations.

The paper presents a comparative study of various models used to estimate gas dynamics in internal combustion engine (ICE) ducts. 1D models provide a sufficient accuracy, but they are still not implementable on current ECUs. On the other hand, low order models can be real-time but their lack of accuracy and high calibration cost are still a challenging problem. This work aims at presenting a comparison of currently used gas dynamics models to predict transient phenomena in engine ducts. It emphasizes on 1D and low order models. To test under engine-like conditions, the intake path of a virtual engine implemented in GT-Power and a production two cylinder engine are used. Results show a contrast in the performance of the different models, which gives the possibility to evaluate the various approaches. Based on this assessment and depending on the application in hand, the models can be chosen properly to estimate the gas dynamics in internal combustion engine ducts.

Contemporary diesel engines are high-tech power plants that provide high torques at very good levels of efficiency. By means of modern injecting-systems such as Common-Rail Injection, combustion noise and emissions could be influenced positively as well. Diesel engine are therefore used increasingly in top-range and sports cars. Today's production ECUs have no or only very low feedback regarding the process in the combustion chamber. As long as this data is missing, the design of the maps in the ECU can only be a compromise, since production tolerances and aging processes have to be considered in advance. Disturbances in the combustion process may not be detected at all. If more knowledge about the course of combustion is provided, especially the start of combustion (SOC), various operating parameters, such as the pilot injection quantity or the beginning of current feed to the injector, could be adjusted more precisely and individually for every cylinder.

On the way to automated driving, the installation rate of surround sensing systems will rapidly increase in the upcoming years. The respective technical progress in the areas of driver assistance and active safety leads to a numerous and valuable information and signals to be used prior to, during and even after an accident. Car makers and suppliers can make use of this new situation and develop integrated safety functions to further reduce the number of injured and even deaths in car accidents. Nevertheless, the base occupant safety remains the core of this integrated safety system in order to ensure at least a state-of-the-art protection even in vehicles including partial, high or full automation. Current networked safety systems comprehend a point-to-point connection between single components of active and safety systems. The optimal integration requires a much deeper and holistic approach.

When investigating the posture comfort in vehicles two important influencing factors can be distinguished: In order to evaluate these influences a combined laboratory-field-experiment was carried out. A real car was equipped with cameras to record the body posture and the joint angles. The static forces exerted by the driver on his contact points were recorded in a corresponding mock-up. The forces to maintain the body posture were calculated. The following results were found: