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Model-based software development and automatic code generation have become increasingly established in recent years. The automotive industry has widely adopted and successfully deployed these methods in many different series production programs worldwide. This brought various benefits, such as a reduction in development times, improved quality due to more precise specifications, and early verification and validation by means of simulation. At the same time, more and more safety-related and safety-critical systems have been - and will be -introduced into modern vehicles. Common examples are active front steering, adaptive cruise-control, and integrated chassis control. This leads to the question, if and how model-based design and automatic production code generation can be applied to the development of safety-critical systems.

Model-based development of embedded automotive control software is characterized by the use of executable models throughout the entire development process. Modeling and simulation tools that are frequently used in this context include, for example, Simulink and Stateflow from The MathWorks. Code generators such as TargetLink make it possible to automatically generate efficient C code directly from these models. The quality of the models used for code generation has a direct influence on the quality of the generated C code. This is why it is vital that specific quality criteria be fulfilled when developing safety-relevant systems, for example, conformity with modeling guidelines starting at the model level. MISRA modeling guidelines exist for use with the TargetLink code generator. Conformity with these guidelines ensures a safe language subset and significantly improves the safety of generated code, for example, by avoiding ambiguous semantics.

This paper will first introduce and classify the basic principles of architecture-driven software development and will briefly sketch the presumed development process. This background information is then used to explain extensions which enable current behavior modeling and code generation tools to operate as software component generators. The generation of AUTOSAR software components using dSPACE's production code generator TargetLink is described as an example.

Embedded software in the car is becoming increasingly complex due to the growing number of software-based controller functions and the increasing complexity of the software itself. Model-based development with Simulink combined with TargetLink for automatic code generation helps significantly to improve the quality of the embedded software. The development of large-scale Simulink models in distributed teams is a challenging task, especially when developing safety-critical software that must fulfill requirements stated in the ISO 26262 [1] safety standard. In practice, many questions on how to avoid the pitfalls of distributed model-based development remain open, such as how to define an appropriate model architecture, handle model complexity, and achieve compliance with ISO 26262. The intent of this paper is threefold. Firstly, we summarize those requirements of ISO 26262 that are relevant for developing complex software in a distributed environment.

Automatic code generation is an established technology in automotive and aerospace industries that is also adopted in commercial vehicle embedded software development. Code generation brings the productivity gains of model-based algorithm design to the next stage of the process – production software development. The technology has matured to the point where it satisfies most technical and usability requirements and the success of code generation depends on judicious deployment, efficient work practices and acceptance by all users involved. It has been demonstrated that model-based software development and code generation in particular can shorten development cycles while staying true to the requirements and maintaining software quality through multiple algorithm iterations. These gains, though, only come as a result of careful combination of tools and methods. This paper discusses solutions to common organizational and technical challenges of model-based software development.

Model-based development and autocoding have become common practice in the automotive industry over the past few years. The industry is using these methods to tackle a situation in which complexity is constantly growing and development times are constantly decreasing, while the safety requirements for the software stay the same or even increase. The debate is no longer whether these methods are useful, but rather on the conditions for achieving optimum results with them. From the experiences made during the last decade this paper shows some of the key factors helping to achieve success when introducing or extending the deployment of automatic code generation in a model-based design process.