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The Side View Assist is the World’s first rider assistance system for two-wheelers. This is a Blind Spot Warning system, which uses four ultrasonic sensors to monitor the surrounding of the rider. Whenever there is a vehicle (i.e. a car, truck, or another motorbike) in the rider’s blind spot, the technology warns the rider with an optical signal close to the mirror. This will allow the rider to avoid a collision when changing lanes. In the current vehicle application, Side View Assist is active at speeds ranging from 25 to 80 kilometers per hour and supports riders whenever the difference in relative speed to other road users is small. The system helps to improve safety especially in cities, where heavy traffic makes it necessary to change lanes more often. Originally such systems have been developed for cars and different system solutions for cars have been in serial production for several years. The challenge was to adapt these systems so they would work for two-wheelers as well.

Anti-lock Braking Systems (ABS) for motorcycles have already contributed significantly to the safety of powered two-wheelers (PTW) on public roads by improving bike stability and controllability in emergency braking situations. In order to address further riding situations, another step forward has been achieved with Motorcycle Stability Control (MSC) system. By combining ABS, electronically combined braking system (eCBS), traction control and inertial sensors even in situations like braking and accelerating in corners the riders' safety can be improved. The MSC system controls the distribution of braking and traction forces using an algorithm that takes into account all available vehicle information from wheels, power train and vehicle attitude. With its ability to control fundamental vehicle dynamics, the MSC system will be a basis for further development and integration of comprehensive safety systems.

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].

Based on the fuel consumption analysis methods published on last year's SETC [1], we compared fuel economies of a typical 125cc production motorcycle equipped with either electronic (port) fuel injection (EFI/PFI) engine management system (EMS) or constant vacuum carburetor (Carb). In addition to earlier discussed PFI results, stationary engine map measurements of fuel consumption on an engine dynamometer (dyno) were conducted for the Carb engine. The powerful development tool of fuel consumption test cycle simulation uses these stationary engine dyno results to calculate fuel consumption of real transient vehicle operation. Here it was employed to assess economy of both fuel system configurations under different driving conditions. Besides the Indian Driving Cycle (IDC) and the World Motorcycle Test Cycle (WMTC), we investigated real world drive patterns typical for emerging markets in terms of a Bangalore urban cycle and a Malaysian suburban cycle.

Environmental consciousness and tightening emissions legislation push the market share of electronic fuel injection within a dynamically growing world wide small engines market. Similar to automotive engines during late 1980's, this opens up opportunities for original equipment manufacturers (OEM) and suppliers to jointly advance small engines performance in terms of fuel economy, emissions, and drivability. In this context, advanced combustion system analyses from automotive engine testing have been applied to a typical production motorcycle small engine. The 125cc 4-stroke, 2-valve, air-cooled, single-cylinder engine with closed-loop lambda-controlled electronic port fuel injection was investigated in original series configuration on an engine dynamometer. The test cycle fuel consumption simulation provides reasonable best case fuel economy estimates based on stationary map fuel consumption measurements.

Active safety systems will have a great impact in the next generation of vehicles. This is partly originated by the increasing consumer's interest for safety and partly by new traffic safety laws. Control actions in the vehicle are based on an extensive environment model which contains information about relevant objects in vehicle surroundings. Sensor data fusion integrates measurements from different surround sensors into this environment model. In order to avoid system malfunctions, high reliability in the interpretation of the situation, and therefore in the environment model, is essential. Hence, the main idea of data fusion is to make use of the advantages of using multiple sensors and different technologies in order to fulfill these requirements, which are especially high due to autonomous interventions in vehicle dynamics (e. g. automatic emergency braking).

With its origin in the process industry, the IEC 61508 „Functional safety of electrical/electronic/programmable electronic safety-related systems” is not fully applicable in the automotive industry, forcing the automotive industry to work on an automotive specific adaptation (ISO 26262 “Functional Safety – Road Vehicles”). This ISO 26262 describes an ideal development process that starts from scratch. In reality development activities are often split locally and in time. This can only be handled with a world wide standard as a basis of a common approach, wide enough to give enough freedom to adapt to diverse boundary conditions, but tight enough to hinder local interpretations to be that far, that a complete safety case becomes impossible. Therefore a strict world-wide standard which allows compatible interpretations is mandatory.

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.

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.

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.

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.

ABS has proven to be a contribution to active safety. The introduction of traction control (TC) in 1986 and even more significantly, the introduction of vehicle dynamics control (VDC) in 1995 have been further milestones in this field. The functionality of these systems (ABS, TC, VDC) is mainly determined by the electronic control unit (ECU). A system supplier who is to provide an ECU-platform concept including a large functionality, while meeting customer specific requirements at an optimized price, needs standardization strategies. This paper describes a standardization concept for an ABS ECU, beginning with the basic ABS HW and SW design and the extension to TC and VDC. It also shows the degree of flexibility, the benefits for the vehicle manufacturer and the possible cost optimization for the system supplier.

This paper presents the Vehicle Dynamics Control (VDC) for commercial vehicles developed by BOSCH. The underlying physical concept is discussed in the second section after a short introduction. The third section shows the computer simulation used in the development process. Section four describes the controller structure of the VDC system. In Section five the use and effectiveness of VDC for commercial vehicles is shown in different critical driving situations. This is done by using measured data collected during testing (lane change, circular track) and it demonstrates that the safety improvements achieved for passenger cars are also possible for commercial vehicles.

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.

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.

A new automotive active safely system, the Vehicle Dynamics Control System (VDC) of BOSCH was introduced on the market in 1995. Besides improving the ABS/ASR functions, VDC will also actively support the driver in critical situations of lateral vehicle dynamics. This system includes new ABS/ASR-control algorithms and a superimposed control algorithm, the vehicle dynamics controller. Furthermore, an extension of the standard ABS/ASR-hydraulic system was necessary as well as the development of new automotive sensors. During all phases of the interdisciplinary system development, tests on experimental cars and extensive computer simulations were used in parallel. In order to provide adequate simulation models for different tasks, a modular concept for the simulation tool is important. Furthermore, a transparent and portable application of the control algorithm for both, experiment and simulation, is required.

From the beginning of 1995 on, RB will start the production of the Vehicle Dynamics Control System. A key part of this system is the Yaw Rate Sensor described in this paper. The basic requirements for this sensor for automotive applications are: mass producibility, low cost, resistance against environmental influences (such as temperature, vibrations, EMI), stability of all characteristics over life time, high reliability and designed-in safety. Bosch developed a sensor on the basis of the “Vibrating Cylinder”. The sensor will be introduced into mass production in beginning of 1995.

VDC is a new active safety system for road vehicles which controls the dynamic vehicle motion in emergency situations. From the steering angle, the accelerator pedal position and the brake pressure the desired motion is derived while the actual vehicle motion is derived from the yaw rate and the lateral acceleration. The system regulates the engine torque and the wheel brake pressures using traction control components to minimize the difference between the actual and the desired motion. Included is also a safety concept which supervises the proper operation of the components and the software.

An electronic control of throttle angle is required for safety systems like traction control (ASR) and for advanced engine management systems with regard to further improvements of driving comfort and fuel economy. For applications, in which only ASR is required, two versions of a new traction control actuator (TCA) have been developed. Their function is based on controlling the effective length of the bowden cable between the accelerator pedal and the throttle. Besides retaining the mechanical linkage to the throttle, the concept has no need for a pedal position sensor, which is necessary for a drive-by-wire system. Design and performance of both actuators are described and their individual advantages are compared. Moreover, the communication of the system with ASR and its behaviour with regard to vehicle dynamics are illustrated.

Today's ABS sytems for commercial vehicles and trailers reflect specific solutions for individual vehicle model wiring and control features. In addition, the chassis mounting requirements for trailer applications uses a separate sealed housing for the relay and other sensitive components. A logical progression of design development resulted in the new ABS 6S/4K open system with the ability of being adaptable to specific vehicle control requirements. A variety of different component arrangements can be accommodated. Accordingly, it does not require a standard wiring harness. Wiring is left optional for the specific vehicle configuration. The housing may be frame mounted without any special protection and therefore can cover both trailer and tractor applications. The housing is designed to provide necessary protection from water and dirt. The electronic senses the peripheral component configuration via a simple “learning” procedure.