Software correction of geometric errors for multi-axis systems

Accuracy control for software-controlled multi-axis systems (i.e. machining centers and CMMs) is an important problem for contemporary industry. The paper concerns a method of systematic geometric errors correction for such systems. Practically this method increases machining and measuring accuracy without mechanical adjustments of the machine. The goal of accuracy improvement was achieved by means of completing the following tasks: measuring components of volumetric error by means of multi-function laser interferometer; visualizing volumetric error distribution within the machine's workspace (error mapping); developing of error correction strategy based on the mapping; developing of postprocessor for CNC programs in order to get minimal errors within the machine's workspace. The paper includes results of volumetric errors correction for three-axis CNC-controlled precision machine-tools. The results prove adequacy of models and efficiency of the method.