AUTOSAR (AUTomotive Open System ARchitecture)
AUTOSAR (AUTomotive Open System ARchitecture) is a worldwide development partnership of vehicle manufacturers, suppliers and vendors of software and development tools, founded in 2003. It defines a standardized software architecture for electronic control units (ECUs) in vehicles. The goal: software components should be reusable across manufacturer, supplier and platform boundaries — following the guiding principle “Cooperate on standards, compete on implementation”.
The core idea: standardize the architecture, differentiate the implementation
Before AUTOSAR, ECU software was tightly interwoven with the respective hardware: changing the microcontroller or the supplier meant costly porting. AUTOSAR decouples the application software from the hardware through a layered architecture with standardized interfaces: application software components communicate via a runtime environment (RTE) with the underlying basic software, which encapsulates the operating system, communication and hardware access. Software components thus become movable between ECUs, and OEMs can integrate components from different suppliers in one ECU. The standardized exchange format ARXML makes the architecture description exchangeable between tools and organizations.
Classic and Adaptive Platform
Today AUTOSAR comprises two platforms for different classes of ECUs:
| Platform | Target systems | Characteristics |
|---|---|---|
| Classic Platform | Deeply embedded ECUs with hard real-time requirements — e.g. engine control, brake control unit | Statically configured: tasks, communication and memory layout are fixed at development time |
| Adaptive Platform | High-performance computers, for example for automated driving and connected functions | POSIX-based, service-oriented communication, applications loadable and updatable at runtime |
Both platforms exist in parallel — modern vehicles typically combine many Classic ECUs with a few Adaptive high-performance computers.
AUTOSAR is model-based through and through
AUTOSAR development is at its core model-based development: software components, interfaces and system topology are described as models, exchanged as ARXML and processed further by configuration and generation tools — for example to generate the RTE and the basic software configuration. The standard itself is also maintained in a model-based way: the AUTOSAR consortium generates its specification documents from an extensive Enterprise Architect model, which since 2020 has been read out headlessly in a CI pipeline via the EA Bridge.
AUTOSAR in practice: the toolchain is the real task
AUTOSAR standardizes the architecture and exchange formats — not the tool chain. In real projects, development is spread across many tools: the architecture model in a modeling tool, requirements in DOORS or Jama, basic software configuration and code generation in specialized tools, tests somewhere else again. Since AUTOSAR projects almost always concern safety-related functions, standards such as ISO 26262 additionally demand gapless traceability from the requirement down to the code. Precisely this continuity across tool boundaries is, in practice, the biggest hurdle — and the reason why toolchain integration in AUTOSAR projects is not a side issue but a core task.