Optimization of dual NURBS curve fitting in five-axis machining

In order to solve the problem that the curve tool track chord error generated by CAM software in 5-axis machining is out of the given tolerance, this paper proposes a method based on three times double NURBS curve fitting optimization. After the initial fitting of NURBS curve for the tool center point and tool axis point, the curve segments with excessive chord error are detected and the insertion of control nodes is used to ensure that the fitted curve segments meet the given requirements. The simulation of a set of data points illustrates the effectiveness of the method, which can effectively solve the problem of excessive string errors and improve the machining quality of complex free-form surfaces.