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The spatial distribution of internal exhaust gas recirculation (EGR) is evaluated in an optically accessible direct injection spark ignition engine using near infrared laser absorption to visualize the distribution of the H2O molecule. The obtained overall internal exhaust gas recirculation compares well to gas-exchange cycle calculations and the spatial distributions are consistent with those measured with inverse LIF. The experimental procedures described in this report are designed to be simple and rapidly implemented without the need to resort to unusual optical components. The necessary spectral data of the selected absorption line is obtained from the HITEMP database and is validated with prior experiments carried out in a reference cell. Laser speckle in the images is effectively reduced using a ballistic diffuser.

The correct timing of the diesel injection pump on engine is of major importance for all functions of the engine and for its exhaust emissions, during production pass off as well as in the field. Within the diesel service workshops a variety of devices exist to test the timing of the injection pump on engine. Most of them operate by clamp-on transducer being fitted to the injection pipe. A large uncertainty exists concerning the accuracy of such timing systems. Most diesel engine manufacturers do not have confidence in the timing devices capability and, therefore, do not recommend their usage. A working group within the International Organization for Standardization (ISO) adopted a method for the validation of these measurement systems, which usually is used to judge the capability of measurement gauges for industrial production processes.

Increasingly stringent tailpipe emissions regulations have prompted renewed interest in catalyst heating technology – where an integrated device supplies supplemental heat to accelerate catalyst ‘light-off’. Bosch and Boysen, following a collaborative multi-year effort, have developed a Rapid Catalyst Heating System (RCH) for gasoline-fueled applications. The RCH system provides upwards of 25 kW of thermal power, greatly enhancing catalyst performance and robustness. Additional benefits include reduction of precious metal loading (versus a ‘PGM-only’ approach) and avoidance of near-engine catalyst placement (limiting the need for enrichment strategies). The following paper provides a technical overview of the Bosch/Boysen (BOB) Rapid Catalyst Heating system – including a detailed review of the system’s architecture, key performance characteristics, and the associated impact on vehicle-level emissions.

Employing novel surface micromachining techniques, a highly miniaturized, robust device has been fabricated. The accelerometer fulfills all requirements of state-of-the-art airbag systems. The present paper reports on the manufacturing and assembly process as well as the performance of the sensor. The capacitive sensing element consists of a moveable proof mass of polysilicon on a single crystalline silicon substrate. A lateral acceleration displaces the proof mass and a capacitive signal is generated at a comb electrode configuration. An external IC circuit provides the signal evaluation and conditioning in a closed loop mode, resulting in low temperature dependency of sensor characteristics and a wide frequency response. The sensor is fabricated by standard IC processing steps combined with additional surface micromachining techniques. A special deposition process in an epitaxial reactor allows the fabrication of moveable masses of more than 10 µm thickness.

This paper presents advanced planar ZrO2 oxygen sensors being developed at Robert Bosch using a modified tetragonal partially stabilized zirconia (TZP) with high ionic conductivity, high phase stability and high thermo-mechanical strength. Green tape technology combined with highly automated thickfilm techniques allows robust and cost effective manufacturing of those novel sensing elements. Standardization of assembling parts reduces the complexity of the assembly line even in the case of different sensing principles. The sensor family meets the new requirements of modern ULEV strategies like fast light off below 10 s and linear control capability as well as high quality assurance standards. High volume production will start in 1997 for European customers.

In conventional sensor systems, mechanical and electronic components are generally operating at separated locations. Smart sensors integrate mechanical and electronic elements to a single system, thus offering new facilities for a common error compensation. In this concept, a unit-specific temperature dependence and a non-linear characteristic curve of the mechanical sensor element can be tolerated, thus saving a lot of costs in the manufacturing process of the mechanical components. The behaviour of the mechanical sensor element is described by a two-dimensional sensor correction function: Given the output of the mechanical sensor element and a measured value for the temperature, the true measurement value can be calculated by an error correction unit. In this paper, different error correction methods are examined and evaluated which can be used for a wide range of sensor types. They are applied to the example of a short-circuit ring displacement sensor.

The present paper concentrates on the option of catalytic autothermal reforming of gasoline for fuel cell applications. Major parameters of this process are the “Steam to Carbon Ratio” S/C and the air to fuel ratio λ. Computations assuming thermodynamic equilibrium in the autothermal reactor outlet (ATR) were carried out to attain information about their proper choice, as failure in adjusting the parameters within narrow limits has severe consequences on the reforming process. In order to quantify velocity distribution just ahead the catalyst and to evaluate mixing uniformity we designed an ATR featuring an optical access: Thus flow visualization using PIV (Particle Image Velocimetry) and LIF (Laser Induced Fluorescence) technique is possible. Preliminary PIV-results are presented and compared with CFD computations (Computational Fluid D ynamics).

Due to its high number of free parameters, the new generation of gasoline engines with direct injection require an efficient calibration process to handle the system complexity and to avoid a dramatic increase in calibration costs. This paper presents a concept of specific toolboxes within a standardized and automated calibration environment, supporting the complexity of GDI engines and establishing standard procedures for distributed development. The basic idea is the combination of a new and more efficient online DoE approach with the automatic and adaptive identification of the region of interest in the high dimensional parameter space. This guarantees efficient experimental designs even for highly non-linear systems with often irregularly shaped valid regions. As the main advantage for the calibration engineer, the new approach requires almost no pre-investigations and no specific statistical knowledge.

Until now, the use of biometric systems has not been in the public eye. The high cost of sensors and processing has meant that biometrics was previously restricted to high security access, financial transaction and law enforcement applications. However, as a result of improvements in technology, biometric sensor price and reliability have achieved levels where biometrics is being seriously considered for automotive systems. This paper introduces the field of biometrics, the key terms and processes. Fingerprint Technology and Identification by Fingerprint are discussed, as are the use and applicability of biometrics in automotive applications, including Personal Profiling, Keyless Engine Start and vehicle access authorization. The key findings of investigations over the last years are discussed.

In this article a new zero-dimensional model is presented for simulating the cylinder pressure in direct injection diesel engines. The model enables the representation of current combustion processes considering multiple injections, high exhaust gas recirculation rates, and turbocharging. In these methods solely cycle-resolved, scalar input variables from the electronic control unit in combination with empirical parameters are required for modeling. The latter are adapted automatically to different engines or modified applications using measured cylinder pressure traces. The verification based on measurements within the entire operating range from engines of different size and type proves the universal applicability and high accuracy of the proposed method.

The study presented in this paper focuses on measures to minimize exhaust gas emissions to meet SULEV targets on a V6 engine by using a cost efficient system configuration. The study consists of three parts. A) In the first stage, the influence of engine management both on raw emissions and catalyst light off performance was optimized. B) Afterwards, the predefined high cell density catalyst system was tested on an engine test bench. In this stage, thermal data and engine out emissions were used for modeling and prediction of light-off performance for further optimized catalyst concepts. C) In the final stage of the program, the emission performance of the test matrix, including high cell density as well as multifunctional single substrate systems, are studied during the FTP cycle. The presented results show the approach to achieve SULEV emission compliance with innovative engine control strategies in combination with a cost effective metallic catalyst design.

Meeting current exhaust emission standards requires rapid catalyst light-off. Closed-coupled catalysts are commonly used to reduce light-off time by minimizing exhaust heat loss between the engine and catalyst. However, this exhaust gas system design leads to a coupling of catalyst heating and engine operation. An engine-independent exhaust gas aftertreatment can be realized by combining a burner heated catalyst system (BHC) with an underfloor catalyst located far away from the engine. This paper describes some basic characteristics of such a BHC system and the results of fitting this system into a Volkswagen Touareg where a single catalyst was located about 1.8 m downstream of the engine. Nevertheless, it was possible to reach about 50% of the current European emission standard EU 4 without additional fuel consumption caused by the BHC system.

Additional future requirements for automobiles such as improved vehicle dynamics control, enhanced comfort, increased safety and compact packaging are met by modern electrical steering systems. Based on these requirements the new functionality is realized by various additional electrical components for measuring, signal processing and actuator control. However, the reliability of these new systems has to meet the standard of today's automotive steering products. To achieve the demands of the respective components (e.g. sensors, bus systems, electronic control units, power units, actuators) the systems have to be fault-tolerant and/or fail-silent. The realization of the derived safety structures requires both expertise and experience in design and mass production of safety relevant electrical systems. Beside system safety and system availability the redundant electrical systems also have to meet economic and market requirements.

Historically, whenever the automotive solutions’ state of art reaches a saturation level, the integration of new verticals of technology has always raised new opportunities to innovate, enhance and optimize automotive solutions. The predictive powertrain solutions using connectivity elements (e.g., navigation unit, e-Horizon or cloud-based services) are one of such areas of huge interest in automotive industry. The prior knowledge of trip destination and its route characteristics has potential to make prediction of powertrain modes or events in certain order and therefore it can add value in various application areas such as optimized energy management, lower fuel consumption, superior safety and comfort, etc.

Aerodynamic styling is playing an increasing role in the design of today's passenger cars. The profile sections of the frontends of cars imply that the available installation space for the headlamps - particularly its overall depth and height is decreased in size. New types of headlamps had to be developed. One result of extensive investigations are stepped reflectors with up to six paraboloids with different focal lengths arranged around the same focal point. This type of reflector (called homofocular reflector) cannot be formed from sheet steel but from plastic by injection molding. Depending on thermal, mechanical and geometric boundary conditions three different reflector materials can be used: lacquered thermosets, unlacquered thermoplastics by one or two material injection moldings. Similar to sheet steel the use of glass lenses reduces considerably the freedom of the designer. This disadvantage of offset by the use of plastic lenses.

Modern agricultural tractors are equipped with a hitch control system. These may be mechanical-hydraulic, hydraulic-hydraulic, or electronic-hydraulic. With the variety of design options open to the tractor manufacturer, it is important to select the system which best fits the manufacturer and end user. This paper presents a comprehensive comparison of each system. Robert Bosch has had many years experience in the design and manufacture of components for hitch systems, and hopes to help designers choose the approach best suited for them.

In order to optimize the performance and emission of engines, advanced control and diagnostic systems require detailed feedback information about the combustion process. In this context, cost-effective solutions are of interest. The contribution describes a method for reconstructing cylinder-individual features of each combustion cycle by processing the instantaneous fluctuations of the engine speed and the in-cylinder pressure of one cylinder. Model-based torque estimation, analyzing both of the signals simultaneously, provides an accurate estimation of the mean indicated pressure. Using this method, a new algorithm for advanced misfire detection is presented. Furthermore, a new pressure model with a feasible number of parameters is proposed. It is combined with the torque estimation in order to reconstruct the unknown pressure traces of the cylinders not equipped with sensors.

A single-chip integrated barometric pressure sensor using bulk silicon micromachining will be presented in this paper. The sensor chip incorporates the complete signal evaluation and trimming of the temperature coefficients and manufacturing tolerances. Sensor chips are mounted onto 6″ × 4″ thick film substrates for batch processing during assembly and trimming. The separated, individual devices can be used for surface mounting (SMD) on a printed circuit board (PCB). Specifications for the sensor functions, as well as the assembly and packaging concept, will be discussed. Assembly, trimming and packaging are the most expensive production steps in the manufacture of sensors. In order to reduce the costs for sensors, we are introducing a standardization of sensor assembly and trimming with batch processing capability: after dicing, the integrated sensor chip is attached to a 6″ × 4″ thick film ceramic substrate with standard die-attaching glue.

An integrated manifold pressure sensor using bulk silicon micromachining techniques is presented. The sensor incorporates the entire signal amplification, temperature compensation, and circuitry for electronic trimming of the sensor chip. The chip circuitry and the manufacturing and assembly process will be discussed. Trimming of the sensitivity and offset production tolerances as well as the temperature coefficients of sensitivity and offset is performed using an electrical trim method. A binary coded digital compensation information is serially fed into an on-chip control unit. The individual bits are decoded and sent to the gates of a bank of trimming thyristors. Once the correct binary code has been selected so that the sensor characteristic is centered in the specified range, the programming voltage is increased and the data is irreversibely stored similarly to the zener zapping method.

1 High precision high pressure diesel common rail fuel injection systems play a key role in emission control, fuel consumption and driving performance. Deposits have been observed on internal injector components, for example in the armature assembly, in the slots of the piston and on the nozzle needle. The brownish to colourless deposits can adversely impact driveability and result in non-compliance with the Euro 4 or Euro 5 emission limits. The deposits have been extensively studied to understand their composition and their formation mechanism. Due to the location of these deposits, the influence of combustion gas can be completely ruled out. In fact, their formation can be explained by interactions of certain diesel fuel additives, including di- and mono-fatty acids. This paper describes the methodology used and the data generated that support the proposed mechanisms. Moreover, approaches to avoid such interactions are discussed.