RAG-Supported Circularity Translation Framework for Supplier-Level Automotive Requirements Engineering

This study presents a retrieval-augmented generation (RAG)-supported framework for translating circularity-related information into actionable engineering implications for lower-tier automotive suppliers. The approach addresses the gap between vehicle-level circularity objectives and the component-, material-, and process-level decisions required within supplier product development. The developed Circularity Translation Cube (CTC) structures circularity-related issues along three dimensions: Circularity Driver, Engineering Level, and Translation Maturity. The framework specifies RAG-supported retrieval and translation of normative information as a source-grounded support function, while applicability, evidence assessment, and engineering decisions remain under human control. The framework is illustrated through three theoretical vehicle-interior supplier scenarios covering normative, customer/supply-chain, and strategic engineering inputs. The scenarios illustrate differentiated supplier responses, including documentation, verification, monitoring, and redesign. A structured assessment using the Validation Square supports the conceptual consistency of the framework and identifies the limitations of the theoretical application setting. The framework adopts the design assumption that supplier-oriented translation can be supported with limited input information and modelling effort, while connecting heterogeneous circularity information with traceable engineering responses. Further empirical application is required to assess the method’s practical effectiveness and suitability for industrial supplier development.