Initialization of cutting tools and milling paths for 5-axis CNC flank milling of freeform surfaces

Tool shape selection and path planning are critical for 5-axis CNC flank milling of freeform surfaces, typically addressed using optimization algorithms where initialization plays a pivotal role. Existing approaches rely on user-specified initialization of either tool shapes or motion paths, often resulting in suboptimal outcomes. This paper introduces a fully automated method that simultaneously initializes both tool shapes and motion paths, achieving high-precision machining with efficient surface coverage. Our approach explores a solution space of potential tool axes represented by line segments near the design surface. To efficiently manage the vast number of lines, we integrate space voxelization with a discrete distance field for effective line sampling. A graph-based algorithm generates feasible line sequences for motion paths, while path optimization refines a single tool shape across multiple paths simultaneously. The method identifies optimal tool shapes of various sizes, each paired with corresponding motion paths for multi-pass machining. Experiments on industrial benchmark models and freeform surfaces validate the effectiveness and practicality of the proposed approach.