A novel five-axis on-machine measurement error prediction model considering positioning errors of machine tool

In comparison to coordinate measuring machine (CMM), on-machine measurement (OMM) offers the benefit of avoiding re-clamping of workpieces and has become a crucial technology for adaptive machining. In OMM, the positioning errors of machine tool shift the ideal position and orientation between the probe and the workpiece. This introduces an error in the measurement result, causing workers to question OMM’s precision. Therefore, the clarification of the relationship between positioning error and OMM error is helpful to make this technique more reliable. For this purpose, a five-axis OMM error model considering positioning errors is proposed. First, this paper gives the definition of feasible measurement region (FMR) about five-axis machine tool and obtains the FMR under specified measurement feature. Then, in the interest of identifying the influence of machine tool positioning error on OMM accuracy, an OMM error prediction model considering positioning error is established, which can be used to predict the error distribution in FMR. Next, the validity of the prediction model is verified by OMM experiments on the standard block. Finally, several applications of the OMM error prediction model are proposed.