Introducing the detailed semantic interface description to support a modular safety approval of automated vehicles – S2I2

Abstract

The concept of a modular safety approval for automated vehicles dispenses with tests on vehicle or system level. Individually approved modules can be updated and reused without requiring new safety approvals. Similar to a system’s operational design domain description, an environmental description is required for a safety approval on module level. This paper presents how the environment of a module can be described at module interfaces. Uncertainty about other modules’ behaviour, dependencies between modules, and impacts of their outputs on the system behaviour are key reasons for missing specifications or tests of existing methods, leading to an erroneous approval of modules. To reduce uncertainties, we expand the state-of-the-art syntactical and semantic interface description and additionally describe dependencies to other modules’ behaviour or conditions and impacts of their outputs. The resulting detailed semantic interface description is categorised into syntax, semantics, influencing factors, and impacts. The novel description structure is a condensed way to consider the behaviour and its impacts on other modules in module development and testing. The description fundamentally supports the modular safety approval by identifying stimuli usually only seen during integration.