MES Utilisation Within Intelligent Manufacturing Systems: A Hierarchical Integration Framework and KPI-Based Verification

The increasing complexity of global manufacturing environments demands seamless vertical integration of information systems across all enterprise levels. Manufacturing Execution Systems (MES) occupy a critical intermediate tier between shop-floor automation and Enterprise Resource Planning (ERP); however, their systematic integration with Intelligent Manufacturing Systems (IMS) remains insufficiently formalised. The primary objective of this study is to develop and empirically validate a structured four-stage integration methodology enabling ISA-95-compliant MES to serve as the real-time supervisory and data bridge within IMS environments, without requiring architectural modification to either system. This paper proposes a comprehensive four-stage MES–IMS integration methodology grounded in the ISA-95 enterprise-control framework and the MESA collaborative MES model. The methodology encompasses: (i) identification of MES and IMS baseline characteristics; (ii) definition of collaborative activities; (iii) design of a hierarchical communication model; and (iv) specification of bidirectional data-exchange requirements including Key Performance Indicators (KPIs). The proposed framework was experimentally verified on the FESTO FMS 500 within the Žilina Intelligent Manufacturing System (ZIMS) concept. An original hierarchical MES–IMS model was derived, articulating vertical and horizontal communication flows across three enterprise tiers. A structured KPI taxonomy—covering equipment effectiveness, process throughput, quality, and workforce metrics—was formulated and validated against FMS 500 station data (23 indicators). MES can serve as the primary intelligence-supporting layer within IMS, providing real-time supervisory and data bridging capabilities. The proposed framework offers a replicable integration pathway aligned with Industry 4.0 paradigms.