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Car Periphery Supervision (CPS) systems comprise a family of automotive systems that are based on sensors installed around the vehicle to monitor its environment. The measurement and evaluation of sensor data enables the realization of several kinds of higher level applications such as parking assistance or blind spot detection. Although a lot of similarity can be identified among CPS applications, these systems are traditionally built separately. Usually, each single system is built with its own electronic control unit, and it is likely that the application software is bound to the controller's hardware. Current systems engineering therefore often leads to a large number of inflexible, dedicated systems in the automobile that together consume a large amount of power, weight, and installation space and produce high manufacturing and maintenance costs.

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.

Tapping of one or more torques (ranges 10 Nm and 60 Nm) on the steering column for the purpose of servo control must satisfy high accuracy requirements on the one hand and high safety requirements on the other hand. A suggestion for developing a low-cost solution to this problem is described below: Strain gages optimally satisfy both these requirements: However, for cost reasons, these are not applied directly to the steering column but to a prefabricated, flat steel rod which is laser welded to the torque rod of the steering column. The measuring direction of the strain gages is under 45° to the steering column axis. The strain gages are either vacuum metallized onto the support rod as a thin film or laminated in a particularly low-cost way by means of a foil-type intermediate carrier.

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 is based on the experiences with Adaptive Cruise Control (ACC) systems at BOSCH. Necessary components (especially range sensor, curve sensors, actuators and display) are described, roughly specified, and their respective strength and weaknesses are addressed. The system overview contains the basic structure, the main control strategy and the concept for driver-ACC interaction. Afterwards the principal as well as the current technical limits of ACC systems are discussed. The consequences on traffic flow, safety and driver behavior are emphasized. As an outlook, development trends for extended functionality are given for the next generation of driver assistance systems.

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.

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.

The ongoing changes in the development of new power trains and the requirements due to driver assistance systems and autonomous driving could be the enabler for completely new brake system configurations. The shift in the brake load collective has to be included in the systems requirements for electric vehicles. Many alternative concepts for hydraulic brake systems, even for decentralized configurations, can be found in the literature. For a decentralized system with all state of the art safety functionalities included, four actuators are necessary. Therefore, the single brake module should be as cost-effective as possible. Previous papers introduced systems which are for example based on plunger-like concepts, which are very expensive and heavy due to the needed gearing and design. In this paper a comparison between a state of the art hydraulic brake system using an electromechanical brake booster, and a completely new decentralized hydraulic brake concept is presented.

The assignment of vehicles detected by distance sensors to lanes relative to the own vehicle is an important and necessary task for future driver assistance systems like Adaptive Cruise Control (ACC). The collective motion of objects driving in front of the vehicle allows a prediction of the vehicle's own driving course. The method uses not only data of the host vehicle to determine its own trajectory but as well data from a distance sensor supplying distances and angles of objects ahead of the vehicle to determine the trajectories of these objects. Algorithms were developed using an off-line simulation, which was fed with recorded data obtained from a real ACC vehicle. The results show a significant improvement in the quality of the predicted driving course compared to other methods solely based on data of the host vehicle. Particularly in situations of changing curvature, e.g. the beginning of a bend, the algorithm helps to improve the overall system performance of ACC.

New technologies like alternative power trains and driver assistance systems have a big impact on brake system development. Most of the development work aims at the improvement of the actuation and modulation components of the brake system. The basic hydraulic network remained nearly the same over decades and still has to meet these new requirements. Previous papers have focused mainly on studying the behavior of single components, like for example the brake hose fluid consumption in detail. Other papers studied the complete system but simplified it extremely, so that some relevant effects are neglected. In this work, one focus is to study the influence of single relevant components, like the hydraulic unit and the hoses on the overall system performance. For this measurements with a complete hydraulic brake system, including a state of the art electromechanical brake booster and single component measurements for identification, are conducted.

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.

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.

The SAE J2716 SENT (Single Edge Nibble Transmission) Protocol has entered production with a number of announced products. The SENT protocol is a point-to-point scheme for transmitting signal values from a sensor to a controller. It is intended to allow for high resolution data transmission with a lower system cost than available serial data solution. The SAE SENT Task Force has developed a number of enhancements and clarifications to the original specification which are summarized in this paper.