Optimisation of production scheduling and sequencing problems in Industry 4.0

This article presents an initial overview of optimisation models applied to production scheduling and sequencing in the Industry 4.0 (I4.0) environment. It reviews algorithms based on operational research technologies and artificial intelligence within an I4.0 framework; i.e. models and algorithms that simultaneously incorporate physical and digital Internet solutions, communications and data processing, and intelligence and management. The main findings of this article show that, despite many articles introducing I4.0 concepts or applying some of their principles to production scheduling and sequencing, a real interaction between the real-time data of the physical system and its simulation using digital twins (DTs) is still lacking. Finally, it is important to highlight that one of the most popular scheduling and sequencing approaches is the job shop and most articles are about cross-sector problems.