3DprintMIND: An AI-Agent system using large language models and dynamic manufacturing knowledge graphs for smart manufacturing

As an advanced manufacturing paradigm, 3D printing offers significant opportunities for smart manufacturing (SM). However, the prevalence of data silos in its production lines frequently hinders effective process analysis and decision-making. While large language models (LLMs) possess powerful analytical capabilities, their reliability in industrial scenarios is constrained by hallucinations and a disconnection from real-time operational data. Dynamic manufacturing knowledge graphs (MKGs), functioning as structured databases, can integrate structured and unstructured manufacturing data while providing LLMs with real-time data support. Meanwhile, the development of retrieval-augmented generation (RAG) and AI-Agent technologies provides a feasible pathway for the industrial application of LLMs. This study proposes an end-to-end framework ranging from knowledge integration to 3D printing production line applications to enable reliable LLM-driven SM. Firstly, leveraging the semantic analysis capabilities of LLMs, production data and manufacturing knowledge are integrated into a dynamic MKG. Subsequently, an advanced temporal graph network (TGN) model is developed for representation learning on the dynamic MKG, forming the retrieval foundation of an RAG system. A closed-loop manufacturing logic tailored to 3D printing production lines and a “semantic-to-structured” workflow for anomaly analysis were proposed. Finally, an AI-Agent system and a prototype software platform have been developed, and a case study on a laboratory 3D printing production line has been conducted to evaluate the TGN model's performance and the AI-Agent system's effectiveness. The results indicate that the dynamic MKG enables continuous learning for SM and provides industries with robust AI-driven data support. The TGN model significantly outperforms baseline models, yielding higher-quality dynamic embeddings for downstream knowledge retrieval tasks. Moreover, the AI-Agent system offers SM reliable intelligent analysis and decision support in 3D printing production lines.