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Technical Paper

OSEKtime: A Dependable Real-Time Fault-Tolerant Operating System and Communication Layer as an Enabling Technology for By-Wire Applications

2000-03-06
2000-01-1051
The new generation of drive-by-wire systems currently under development has demanding requirements on the electronic architecture. Functions such as brake-by-wire or steer-by-wire require continued operation even in the presence of component failures. The electronic architecture must therefore provide fault-tolerance and real-time response. This in turn requires the operating system and the communication layer to be predictable, dependable and composable. It is well known that this properties are best supported by a time-triggered approach. A consortium consisting of German and French car manufacturers and suppliers, which aims at becoming a working group within the OSEK/VDX initiative, the OSEKtime consortium, is currently defining a specification for a time-triggered operating system and a fault-tolerant communication layer.1 The operating system and the communication layer are based on applicable interfaces of the OSEK/VDX standard.
Technical Paper

Anti-Lock Braking System for Commercial Vehicles

1988-10-01
881821
Commercial vehicles must convey people and goods safely and reliable, irrespective of the weather and road conditions. The ABS safety braking systems are an essential prerequisite for fulfillment of this primary task. ABS has been used in European commercial vehicles since 1981. Today there are already fittet as standard in buses to some extend. The contribution to increasing road safety is causing the European lawmakers to make ABS statutory for commercial vehicles and to make it part of their compulsory equipment. Suitable anti-lock braking systems and closed loop configurations for commercial vehicles are demonstrated by theoretical observations and technical driving trials, their axlespecific and closed-loop control characteristics are highlighted.
Technical Paper

ASR-Traction Control, State of the Art and Some Prospects

1990-02-01
900204
Closed loop vehicle control comprising of the driver, the vehicle and the environment is now achieved by the automatic wheel slip control combination of ABS and ASR. To improve directional control during acceleration, the Robert Bosch Corporation has introduced five ASR-Systems into series production. In one system, the electronic control unit works exclusively with the engine management system to assure directional control. In two other systems, brake intervention works in concert with throttle intervention. For this task, it was necessary to develop different highly sophisticated hydraulic units. The other systems improve traction by controlling limited slip differentials. The safety concept for all five systems includes two redundant micro controllers which crosscheck and compare input and output signals. A Traction Control System can be achieved through a number of torque intervention methods.
Technical Paper

Antilock Braking Systems (ABS) for Commercial Vehicles - Status 1990 and Future Prospects

1990-10-01
901177
The paper begins with an overview of the history of ABS for commercial vehicles followed by a brief description of the technology of the BOSCH ABS at the time it went into mass production in 1981. Subsequently it describes the field experiences with ABS including the experiences of drivers and operators. These experiences are reflected in the equipment which BOSCH offers today. Additional functions such as ASR (traction control) have been integrated. The paper provides an overview of the functions available today and their implementation. The paper concludes with a discussion on potential continued developments and an attempt to describe the systems which will be required by the mid 9os.
Technical Paper

ABS and ASR for Passenger Cars -Coals and Limits

1989-02-01
890834
Antilock Braking Systems (ABS) and Traction Control Systems (ASR) should ensure maximum stability and steerability even under extreme driving conditions. Since high performance systems additionally improve brake distance and traction within the given physical limits, every vehicle equipped with ABS and ASR offers considerably higher active safety. ABS was introduced into the market by the Robert Bosch GmbH more than ten years ago, and more than 3 million systems have been produced by the end of 1988. Volume production of ASR began in 1987. This paper describes several high-, medium-, and low performance concepts and compares them with regard to safety and performance. Although it seems to be nearly impossible to define a cost/benefit ratio between monetary values and safety, our purpose here is to identify further development strategies through the use of a decision matrix.
Technical Paper

ASR - Traction Control - A Logical Extension of ABS

1987-02-01
870337
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.
Technical Paper

BOSCH-ABS - Designed for the User

1986-11-01
861977
Bosch's antilock braking system (ABS) is available for any type of vehicle design. It has been developed in cooperation with vehicle manufacturers and users. Safety and reliability were the eminent targets of this development. A new feature is a self-diagnostic system.
Technical Paper

Brake by Wire for Commercial Vehicles

1992-11-01
922489
This address presents the ongoing development of the commercial-vehicle braking system, over and beyond ABS/ASR, towards a brake by wire system (electronically controlled braking system ELB) with pressure-regulating circuit and additional functions. Following the discussion and selection of various concepts, we will present different versions with individual and combined components for the towing vehicle and for the trailer. The safety concept of a pneumatic back-up circuit will be dealt with, as well as the communication through data bus (CAN) both within the braking system itself and with other vehicle systems. The improvement possibilities inherent in ELB will be detailed, with the emphasis on increasing road and traffic safety, on reducing operating costs, and on future vehicle-guidance functions.
Technical Paper

ABS5 and ASR5: The New ABS/ASR Family to Optimize Directional Stability and Traction

1993-03-01
930505
In 1978, Bosch was the first supplier on the market to offer full-function antilock braking systems. In 1993, six years will have passed since Bosch delivered the first traction control system for passenger cars. In the meantime, a considerable amount of experience has been gained through ongoing development and testing. This experience enabled us to define the requirements for directional stability, optimum control strategy, maximum usage of the entire spectrum of drive torque intervention possibilities, and optimized hydraulics for automatic brake intervention. The result is Bosch ABS/ASR5, which in now being introduced to the market. This new ABS/ASR family is designed in modules, which offers high flexibility in function and assembly. Systems are available with traction improvement, or with optimized directional stability and traction. Each version is adapted to the needs of the vehicle drive layout, and adaptable to customer requirements.
Technical Paper

New Approaches to Electronic Throttle Control

1991-02-01
910085
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.
Technical Paper

Traction Control (ASR) for Commercial Vehicles. A Further Step Towards Safety on our Roads

1987-11-01
872272
Alongside steering, accelerating and braking are the basic operations in the automobile which are nowadays still left to the driver to perform in their entirety. In performing these basic functions, it may come about that excessive demands are made upon a driver, these arising due to poor road conditions - rain, snow and ice - or as a result of suddenly changing traffic situations. With the introduction of anti-lock braking systems (ABS), a decisive step has been taken to increase active driving and traffic safety. The ABS prevents the lockup of the wheels during overbraking. The vehicle remains steerable and retains stable directional control. Furthermore, in many cases, a shorter braking distance is gained compared to braking with the wheels locked up. BOSCH has been manufacturing and supplying ABS for passenger cars since 1978 and for commercial vehicles and buses since 1981. ABS has proved to be an overwhelming success in practical usage.
Technical Paper

Traction Control (ASR) Using Fuel-Injection Suppression - A Cost Effective Method of Engine-Torque Control

1992-02-01
920641
Traction control (ASR) is the logical ongoing development of the antilock braking system (ABS). Due to the high costs involved though, the widespread practice of reducing the engine power by electronic throttle control (or electronic enginepower control) has up to now prevented ASR from becoming as widely proliferated as ABS. A promising method has now been developed in which fuel-injection suppression at individual cylinders is used as a low-price actuator for a budget-priced ASR. First of all, an overview of the possibilities for influencing wheel-torque by means of intervention at the engine and/or brake as a means of reducing driven wheel slip is presented. Then, the system, the control strategy, and the demands on the electronic engine-management system with sequential fuel injection are discussed. The system's possibilities and its limitations are indicated, and fears of damaging effects on the catalytic converter are eliminated.
Technical Paper

VDC, The Vehicle Dynamics Control System of Bosch

1995-02-01
950759
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.
Technical Paper

ABS5.3: The New and Compact ABS5 Unit for Passenger Cars

1995-02-01
950757
The transition from the multi-component ABS2 design to the one housing concept of ABS5.0 represented a significant step in improving the ABS unit. ABS5.3 is the successor of ABS5.0 to achieve a highly compact, light weight inexpensive design, for the broad use of ABS in all passenger cars and light trucks. New technologies applied are the staking technique for hydraulic components, the use of microhybrid electronics design and solenoid coils being integrated within the attached electronic control unit. The unit can be manufactured in global alliance achieved by simultaneous engineering, applying CAD, FE-analysis, flow calculation and simulation, noise analysis and quality assurance which includes FMEA, error simulation, durability tests and the dry testing concept. The ABS5.3 design can be easily expanded to Traction Control (ASR).
Technical Paper

Loss of Control Car Accidents on Indian Roads - Benefit Estimation of ESC

2019-01-09
2019-26-0009
India has one of the highest growth rates of individual mobility in the world, as well as one of the largest numbers of road casualties. Modern active safety systems are slowly becoming established in the Indian passenger car market. The intension of this study is to investigate the effectiveness of the car safety feature Electronic Stability Control (ESC) for India. The Indian accidents has to be analysed to identify the reliable root cause. For this purpose, passenger car Loss of Control accidents were investigated in more detail with the aim of estimating the safety potential of ESC for India. A methodology is developed to extrapolate the in-depth accident database of Road Accident Sampling System for India (RASSI) to the entire accident situation in India. Loss of Control accidents are analysed with regard to their root causes, crash consequences and contributing factors.
Technical Paper

More Safety with Vehicle Stability Control

2007-11-28
2007-01-2759
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.
Technical Paper

Electronic Braking System EBS - Status and Advanced Functions

1998-11-16
982781
Since 1996 a 2nd Generation EBS has been available in Europe as an advanced brake system offering a variety of advantages to the OEM as well as to the truck and fleet owner. EBS enhances vehicle safety and improves the braking performance to a “passenger car like” braking feel, allowing less experienced drivers better vehicle handling. The brake lining wear control and retarder integration allow the reduction of operational costs. The safety enhancements achieved by EBS in conjunction with disc brakes, are rewarded by European truck insurance companies by lower insurance fees. The importance of EBS will still gain significantly through the developments in process. EBS is the platform for ESP and ACC, which will be a major contributer to better integration of trucks in dense traffic flow.
Technical Paper

Standardization and Cost Optimization of ABS Ecus

1998-10-19
98C004
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.
Technical Paper

Safety and Performance Enhancement: The Bosch Electronic Stability Control (ESP)

2004-10-18
2004-21-0060
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.
Technical Paper

Benefit Estimation of Anti-Lock Braking System for Powered Two Wheeler On Indian Highways

2015-01-14
2015-26-0167
Motorized two wheelers, also known as powered two wheelers (PTW) are the most common mode of transportation in India. Around one in four deaths that occurred on the roads in India in 2012 involved a motorcyclist, according to Ministry of Road Transport and Highways. This constitutes the highest contributor for fatal accidents in India [1]. The European Transport Safety Council (ETSC) analysis shows the risk of a motorcyclist having a fatal accident is 20 times greater than for a car driver travelling the same route [2]. An investigation conducted by Bosch looked at the accident database of Road Accident Sampling System for India (RASSI). This investigation revealed interesting facts about the Indian motorcycle accident situation, such as root causes of powered two wheeler collisions and riders behaviour including their braking patterns during the pre-crash phase of the accident.
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