基于特征的蒙皮镜像铣加工残区刀轨优化方法

镜像铣加工装备及其加工工艺是蒙皮零件加工的有效手段，其特殊工艺对加工刀轨提出了等步距、无交叉、无抬刀且无残留等特殊要求。针对蒙皮零件加工特征的复杂形状，在满足等步距、无抬刀、无交叉的条件下对加工残留区域进行刀轨优化是一个难题。为解决以上难题，本文提出了一种基于特征的蒙皮镜像铣加工残区刀轨优化方法。该方法基于特征将蒙皮零件的工艺信息与几何信息相关联，自动提取加工特征的加工面及其对应的刀轨，将刀轨分割成若干段子刀轨，并构建子加工区域，再利用布尔并运算得到最终可加工区域。然后对加工面区域与最终可加工区域求布尔差识别出加工残留区域，并根据加工残区位置自适应生成满足蒙皮镜像铣特殊要求的优化刀轨。以典型复杂蒙皮零件验证本文提出的方法，结果表明，基于特征的蒙皮镜像铣加工残区刀轨优化方法可自动识别加工残区，并生成满足蒙皮镜像铣特殊要求的加工残区优化刀轨，为提高蒙皮零件数控编程效率提供技术支撑。

Feature-based uncut region tool path optimization method for skin parts machined by mirror milling system

The equipment and the machining process of mirror milling system are effective for aircraft skin parts, whose particular process puts forward special demands on machining tool path, including equal tool path interval, non-cross, no tool retractions and no uncut region. Due to the complex shapes of machining features in aircraft skin parts, it is a difficult task to optimize tool path for uncut regions under the requirements of equal tool path interval, non-cross, no tool retractions. To solve this problem, a feature-based tool path optimization method for uncut regions is proposed. The process information is associated with geometric information based on features, and then the machining surface and its corresponding tool path are extracted automatically. Tool paths are divided into several subdivision tool paths to construct subdivision machining areas, and the final machining area is obtained by union Boolean operation. Then the uncut regions are detected by executing the subtraction Boolean operation between the machining surface area and the final machining area, and the optimized tool path satisfying the special tool path requirements is eventually generated according to the location of the uncut regions adaptively. A typical complex aircraft skin part is used to verify the proposed method and the result proves that uncut regions can be recognized automatically and the optimized tool paths which satisfy the special tool path requirements are generated. The proposed method can provide technical support for improving the NC programming efficiency for aircraft skin parts.