Formalizing dynamic requirements in simulation-driven collaborative design of powertrains

Abstract

Simulation-driven design is widely used to develop complex engineering systems like powertrains. Engineers implement simulations to analyze component interactions, assess system safety requirements, optimize design efficiency, and refine designs before physical prototyping. A central challenge in this process is verifying that systems meet their specified requirements. However, translating these requirements into a machine-readable, unambiguous format that is clear to all stakeholders—such as component providers and system designers—remains difficult.

This thesis introduces a novel approach to dynamic requirement verification in powertrain system design, utilizing an ontology-based framework that integrates the System Structure and Parameterization (SSP) and Functional Mock-up Interface (FMI) standards. The methodology formalizes dynamic requirements using Metric Temporal Logic (MTL) within an ontological structure to represent time-dependent behaviors and constraints. The implementation involves developing an ontology using Protégé, incorporating existing ontologies like the Vehicle Signal Specification Ontology (VSSo) and the Sensor, Observation, Sample, and Actuator (SOSA) ontology, and creating a parser to generate executable verification commands.

The approach was validated using a ship powertrain case study with a known input drive cycle. The study employed both co-simulation and model exchange Functional Mock-up Units (FMUs) to represent system components, with simulations executed in OMSimulator. A requirement verification tool assessed the compliance of the simulated system behavior against the formalized requirements.

The results demonstrated that the developed ontology accurately captured complex dynamic requirements from expert ship designers; integration with SSP and FMI standards improved system-level interoperability. The verification system precisely detected temporal deviations from specified requirements. This research advances systems engineering by offering a structured approach that enables precise specification of dynamic requirements, thereby improving communication and development efficiency in powertrain engineering.