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Fuel economy of two-wheelers is an important factor influencing the purchasing psychology of the consumer within the emerging markets. Additionally, air pollution being a major environmental topic, there is a rising concern about vehicle emissions, especially in the big cities and their metropolitan areas. Potentially, the relatively expensive engine management systems are providing more features and value in comparison to the carburettor counterpart. The combustion system analysis is carried out on a 125 cm3 motorcycle engine and the subsequent numerical simulation comparing the carburettor and the Electronic (Port) Fuel Injection which provides a basis to establish the fuel consumption benefit for the electronic injection systems [1].

The conventional measurements to describe the photometric quality of headlamps usually only comprise the luminous flux and the illuminance (resp. the luminous intensity) in several measuring points given by Type Approval Legislation. Practically, these photometric measurements do not describe the visual impression of a headlamp light distribution sufficiently, neither in lab nor in real street geometry. With the clear outer lens headlamps introduced recently, filament images are projected directly onto the screens or streets, thus giving new impulses to research. Starting from the established photometric practice, other types of measurements and physiological fundamentals will be discussed. The basic tools to make physical measurement and physiological impression comparable, e.g. in terms of homogeneity, are shown.

A new physical layer for automobile class B communication networks is based on simple galvanic connections. Only ten passive external components per node are needed to perform reliable data transmission inside the hostile car environment. Every single fault related to the bus will be detected and diagnosed by every node, where a software controlled logic assures continuous data flow.

In order to prevent injuries due to automatic functions like express- and comfort-opening/closing of power operated window-lift and sunroof systems, mechanisms for detecting obstacles have to be established. The main related regulations are the 74/60/ECC and the FMVSS 118. In this paper we present a unified approach for smart actuators that bases on monitoring the rotational speed of the armature. The advantages have been worked out with the aid of system simulation and proven with tests under realistic and extreme scenarios. The presented results are mainly focused on a sunroof project, which is upcoming for an European car platform in 2001 and is specified to fulfill both regulations simultaneously.

Connecting microcontrollers, sensors and actuators by several communication systems is state of the art within the electronic architectures of modern vehicles. The communication among these components is widely based on the event triggered communication on the Controller-Area-Network (CAN) protocol. The arbitrating mechanism of this protocol ensures that all messages are transferred according to the priority of their identifiers and that the message with the highest priority will not be disturbed. In the future some mission critical subnetworks within the upcoming generations of vehicle systems, e.g. x-by-wire systems (xbws), will additionally require deterministic behavior in communication during service. Even at maximum bus load, the transmission of all safety related messages must be guaranteed. Moreover it must be possible to determine the point of time when the message will be transmitted with high precision.

A major source for soot particle formation in Gasoline-Direct-Injection (GDI) engines are fuel-rich zones near walls as a result of wall wetting during injection. To address this problem, a thorough understanding of the wall film formation and evaporation processes is necessary. The wall temperature before, during and after fuel impingement is an important parameter in this respect, but is not easily measured using conventional methods. In this work, a recently developed laser-based phosphor thermography technique is implemented for investigations of spray-induced surface cooling. This spatially and temporally resolved method can provide surface temperature measurements on the wetted side of the surface without being affected by the fuel-film. Zinc oxide (ZnO) particles, dispersed in a chemical binder, were deposited onto a thin steel plate obtaining a coating thickness of 17 μm after annealing.

Electronic control systems for automatic transmissions have been gaming acceptance in recent years Besides the various types of sensors already in use [for speed, temperature, pressure etc], electro-hydraulic actuators and electronic control units [ECU] are also major constituents of modern control systems Former designs utilized discrete components which were wired together In the interim, actuator modules have been developed for use in new transmission designs As well as presenting actuator concepts, this paper describes a highly integrated and advanced control module This module consists of hydraulic actuators, pilot-solenoid values and an electronic control unit which has been realized in multi-layer hybrid technology

The electrification of the powertrain, the diversity and the complexity of the more or less individual technical solutions which are preferred by different car manufacturers, create a steadily increasing challenge for the whole automotive industry. Missing standards and sales volumes still below the market expectations on the one hand, and the increasing interaction of the main powertrain domains (engine, transmission, e-drive) caused by upcoming cross domain functions on the other hand, lead to increasing development costs and non-optimal solutions concerning fuel economy improvement. Within the domain of engine management systems Bosch established in the mid-nineties the so called torque structure as the solution to a similar situation addressing the coordination of air management, fuel injection and ignition.

All networking systems proposed for the automobile are serial in nature. Most of these systems are also multimaster. A requirement common to all of these systems is the ability to separate framing information from data. This is achieved by some form of code violation for the framing bits which violates the code form for standard data bits. In the Manchester and PWM bit representations this code violation can be signalled within a single bit, NRZ requires more bits. The concept of code violation is also used for signalling errors within a message frame. Clock tolerance is dependent on the length of time over which synchronisation between the serial bit stream and receiving circuitry must be maintained. With a given physical bus line bandwidth, the transport capacity of a protocol is a function of the number of time slots needed to transfer a given number of data bytes.

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.

Control of a car is lost, or considerably reduced, whenever one or more of the wheels exceed the stability limit during braking or accelerating due to excessive brake or drive slip. The problem of ensuring optimum stability, steerability and brake distance of a car during hard braking is solved by means of the well-known Anti-lock Braking System (ABS). The task to guarantee stability, steerability and optimum traction during acceleration, particularly on asymmetrical road surfaces and during cornering maneuvers, is being performed by the traction control system (ASR). Several means to provide an optimum traction control are described, e. g the control of engine torque by influencing the throttle plate and/or the ignition and/or the fuel injection.

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.

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.

This paper will describe the procedures that will enhance the possibilities of qualitative evaluation of headlamp light distributions. A basis will be the description of a light distribution coming only from reflector geometries, i.e. headlamps with clear outer lens design. Further steps of evaluation, as visualization and homogeneity analysis become more and more important for a headlamp evaluation. The recently developed tools can support both the headlamp manufacturer and the car manufacturer in finding a common understanding in headlamp performance of a projected car at a very early stage of development.

A new high-performance interchip interface, called Serial WireRing, is introduced. It combines technically mature and established methods, whereby Serial WireRing provides a simple, robust and very inexpensive solution to replace the Serial Peripheral Interface (SPI). Serial WireRing uses a daisy chain ring topology, realized by unidirectional point-to-point connections from device to device. Serial WireRing is realized by a simple “wire ring” with CMOS, LVDS, optical or any other suitable signaling, even mixed. Therefore it has a very low pin count. In order to minimize the latency each slave transmits the data that it receives with 1 bit delay only. In order to avoid clock/data skew, the serial data and clock are merged into one bitstream. A corresponding clock is extracted at each receiver by a clock and data recovery circuit, driven by a simple internal oscillator.

The electrification of vehicles marks the introduction of new products to the automotive market and a continued effort to optimize their performance. The electric motor is an important component with which a further optimization of efficiency, power density and cost can be achieved. Additional benefits can be realized in the laminated core. This paper presents an innovative method to produce laminated stacks by a chain of processes different from conventional ways. The process chain presents a sequence of precision blanking, buffering, heat treatment and gluing. The effect of these processes is compared with existing solutions that typically contain some individual features but usually not the combination that enhances the overall effect. The heat treatment decreases residual stresses from previous process steps and reduces power losses in the laminated core. Depending on the design, benefits around 20% are found.