Intelligentization of machine tools: comprehensive thermal error compensation of machine-workpiece system

The real-time compensation of thermal errors is an important part of the intelligent functions of machine tools. In order to promote the integrated application of thermal error compensation technique in machine tools, extensive research is still lacking. Thermal error compensation for machine tools and workpiece systems is not widely used, and in-depth research on physically based modeling methods is limited. The thermal behavior of the machine-workpiece system was analyzed, and a thermal error prediction model, based on the heat transfer theory, was established. The effects of screw discretization, as well as single- or multi-heat sources on the physically based prediction model, were analyzed using simulation data. The effect of comprehensive thermal error compensation of the machine-workpiece system was verified in three ways. These ways were measuring with a dual-frequency laser interferometer, machining features visible to the naked eye, and measuring with CMM (coordinate measuring machine). The results proved the high accuracy and strong robustness of the proposed compensation method. This research work will greatly promote the application of thermal error compensation technology in machine tools.