中文摘要：

为选取合适的加工刀具尺寸以对自由曲面实现无曲率干涉加工,提出了改进遗传算法并应用于自由曲面全局最大主曲率求取,确定无曲率干涉最大刀具尺寸。根据主曲率特点设计了一种新的非线性自适应度函数,避免算法过早收敛于局部最优值,并给出了新的复制原则。改进遗传算法应用算例分析表明,该算法在500代内能有效求取自由曲面全局最大主曲率,比传统的离散法效率高,选择的最大刀具尺寸满足自由曲面加工无曲率干涉加工的要求。

英文摘要：

To select appropriate cutter size so as to realize free-form surface machining with no curvature interference,an Improved Genetic Algorithm（IGA） was proposed and applied in global maximum principal curvature calculating of free-form surface and maximum cutter size identifying with no curvature interference.A novel non-linear adaptive fitness function was designed according to principal curvature features,which could avoid trapping in local convergence.New selection rules of units to be copied were also given.Application of IGA showed that the global maximum principal curvature of free-form surface could be calculated effectively within 500 generations and the efficiency was higher than that of the discrete method.The cutter size selected according to the global maximum principal curvature was proper for free-form surface machining with no curvature interference.