Modernising Legacy CNC Lathes for Industry 4.0 and 5.0: A Literature Review and Conceptual Integration Framework

Mechanical Engineering Department, Faculty of Engineering and Quantity Surveying (FEQS), INTI International University, Malaysia

^* Corresponding author: This email address is being protected from spambots. You need JavaScript enabled to view it.

Published online: 19 June 2026

Abstract

Legacy CNC lathes are essential in brownfield plants but are limited by closed controllers, limited semantics, and ISO 6983 G-code. This paper presents a deployable framework: (i) smart retrofitting with edge sensing and gateways; (ii) interoperable connectivity combining MTConnect semantics with OPC UA messaging; (iii) digital twins (DT) integrated with AI for tool condition monitoring (TCM), predictive maintenance (PdM), and remaining useful life estimation; (iv) feature-based programming through STEP-NC; (v) deterministic communications using Time-Sensitive Networking (TSN) with OPC UA Pub/Sub; and (vi) energy-efficient optimisation of cutting parameters. The findings indicate that these components collectively extend machine lifespan, reduce downtime, and enhance energy efficiency while maintaining human-centred operations. Ultimately, a standards-driven retrofit approach allows SMEs to achieve IR 4.0/5.0 goals without complete replacement. Future research should focus on expanding turning datasets for portable DT/AI models, increasing STEP-NC adoption in lathe controllers, and conducting multi-vendor field validation of TSN quality-of-service impacts.