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In this paper, we propose a hardware and a software design method considering functional safety for an electro-mechanical brake (EMB) control system which is used as a brake actuator in a brake-by-wire (BBW) system. A BBW system is usually composed of electro-mechanical calipers, a pedal simulator, and a control system. This simple by-wire structure eliminates the majority of bulky hydraulic brake devices such as boosters and master cylinders. The other benefit of a BBW system is its direct and independent response; this leads to enhanced controllability, thus resulting in not only improved basic braking performance but also considerably easier cooperative regenerative braking in hybrid, fuel-cell, and electric cars. The importance of a functional safety based approach to EMB electronic control unit (ECU) design has been emphasized because of its safety critical functions, which are executed with the aid of many electric actuators, sensors, and application software.

The aim of this paper is to compile the state of the art of engine control and develop scenarios for improvements in a number of applications of engine control where the pace of technology change is at its most marked. The first application is control of downsized engines with enhancement of combustion using direct injection, variable valve actuation and turbo charging. The second application is electrification of the powertrain with its impact on engine control. Various architectures are explored such as micro, mild, full hybrid and range extenders. The third application is exhaust gas after-treatment, with a focus on the trade-off between engine and after-treatment control. The fourth application is implementation of powertrain control systems, hardware, software, methods, and tools. The paper summarizes several examples where the performance depends on the availability of control systems for automotive applications.

The demands of the automotive market are decreasing the time-to-market required from the initial concept of new control systems to their implementation. The goal of automotive companies is to constantly reduce the development time to reap the full economic and strategic benefits of being quicker to market. The target is to reach a development time of less than 12 months for some applications. At the same time, the complexity of these new systems is growing almost exponentially. While new techniques like model-based control design with executable specifications, rapid control prototyping and hardware-in-the-loop simulation have helped significantly streamline the development process, the new strategies are still being transferred to the production target by hand. During an early project phase, automotive customers also need to explore different silicon architectures provided by semiconductor manufacturers to select the vendors who can offer the best solution at the lowest price.

Prototyping of a complete powertrain controller is not generally permissible due to the large number of subsystems involved and the resources required in making the design a reality. The availability of a complete control system reference design at an early stage in the lifecycle can greatly enhance the quality of the system definition and allows early ideas to be prototyped in the application environment. This paper describes the implementation of such a reference design for a gasoline engine and gearbox management control system, integrated into robust housing which can be used for development in a prototype vehicle. The paper also outlines the powertrain subsystems involved, discusses how the system partitioning is achieved, shows the implementation of the partitioning into the physical hardware, and concludes with presenting the system benefits which can be realized.