Implementation independent architecture
The core part of the EAST-ADL, as its name suggests, focuses on the specifications of multi-levelled system design in terms of architectures. As the first step towards the realisation of expected vehicle features, the complete electric functionality of an automotive embedded system can be specified as an implementation independent functional analysis architecture. Such an architecture specification is characterized by the composition of some interacting abstract application functions. Each of these functions is specified by its input-output interfaces, execution patterns, as well as related behavioural and extra-functional constraints. Figure 3 shows a part of the ABS related functional architecture specification. Here ABS_1 function is connected with a brake force request to Brake_1, which is an abstract actuation device (FunctionalDevice). This brake actuation device then provides a physical energy flow representing the actual brake torque.
EAST-ADL follows a type-prototype pattern for component definition and instantiation. For example, the function types such as the ABS and BrakeActuator, can be instantiated multiple times for the different brake instances (in this electric vehicle there are actually four brake function prototypes – one for each of the four brakes).
Similarly to the feature models, the various requirements can be mapped to individual architectural elements, enabling tracing and analysis on how the system meets the various requirements. Here the ABS_1 function is satisfying a Brake force reduction requirement derived from the