Construction of tool remaining useful life indicator for CFRP/titanium stacks drilling using GMM

Carbon fiber reinforced polymers (CFRPs) and titanium (Ti) alloy-based multilayer structures are tremendously advanced materials, broadly employed in the modern aerospace sector due to their superb attributes and operational effectiveness. The quality of drilled holes is essential for the overall assembly quality when joining CFRP composites and titanium alloy through bolting or riveting. Any drilling quality issues can render preceding manufacturing procedures futile, main to a considerable increase in manufacturing costs. This paper focuses on the drilling process of CFRP/titanium stacks, in particular addressing the key technology of tool life prediction. It presents a data acquisition system capable of high-frequency, low-latency, and high-precision data collection and transmission. Through experimental studies, critical sensor monitoring signals and tool life cycle data are obtained during the stacks’ drilling process, developing a labeled machining quality dataset that consists of defects. The tool life prediction indicator employs feature-corrected GMM metrics, and its effectiveness and feasibility are substantiated through the analysis of real-world machining data derived from industrial applications.