Developing sensor signal-based digital twins for intelligent machine tools

•Two JAVA™-based systems to construct the modules of a digital twin and to adapt it for intelligent monitoring of machining processes.•A system capable of dealing with: 1) data updates on a real-time basis, 2) semantically annotated data structure, and 3) uncertainty.•A fast machine learning approach from real-time sensor signals processing.•Digital twins compatible with cyber-physical systems for achieving intelligent machine tools.