A Linear Interpolation Method for Five-Axis Machining Paths on Fan Blisk Surfaces with Constant Theoretical Machining Error

Blisks are complex thin-walled parts with specific structures that have narrow channels and a large degree of bowed-twisted blades. Five-axis machining technology critically influences blisk surface quality and production efficiency, as the toolpath determines machining accuracy for complex curved blades. A method of optimal cutter location calculation for linear interpolation path based on the constraint of equal theoretical machining error is proposed. Based on the kinematics model of the machine tool, the mapping relationship between the trajectory deviation of the five-axis of machine tool and the tool pose deviation in the workpiece coordinate system is established, and then the maximum overcut/undercut value under the coupling action of the tool tip deviation and the tool orientation deviation is estimated. Based on this, a method to estimate the upper limit of theoretical machining error caused during the movement of the tool along the linear path is proposed. And the algorithm for searching discrete cutter locations on the trajectory of cutting contacts is given to maximize the length of linear path based on the constraint of equal machining error. Experimental results demonstrate that the proposed method effectively reduces redundant cutter locations on linear paths and enhances blisk surface quality by replacing conventional constant chord error control with a more preblisk machining error constraint.