针对弱刚性刀具变形导致的深腔模具自由曲面精加工误差预测及补偿问题，本项目运用理论建模、数值仿真和实验分析等方法，将不同性质的加工误差预测及相应补偿贯穿于自由曲面加工前和加工过程中，以实现加工误差的针对性预测和主动性补偿。首先，研究自由曲面加工过程中的切削几何条件变化规律，构建变切削条件下的球头铣刀柔性切削力模型。其次，阐述弱刚性刀具的切削力与变形之间的相互作用机制，建立基于刀具变形的刀触反馈模型，开发切削力-刀具变形平衡迭代算法，求解切削平衡条件下的刀具变形。然后，构建基于优化神经网络的切削力-加工误差映射关系模型，预测名义刀具轨迹下的稳态误差，通过分解误差和修正NC程序，实现加工误差的离线补偿。最后，构建切削功率-加工误差映射关系模型和基于空间数据相似性的切削功率表征模型，通过瞬态误差预测和NC程序的再次修正，实现加工误差的前瞻性过程补偿。该项目有助于提升我国大型深腔注塑模具的制造水平。

Aiming at finishing machining error prediction and compensation induced by low-rigidity tool deflection when machining the free-form surfaces of deep cavity molds, this project adopts theoretical modeling, numerical simulation, and experimental analysis, to predict and compensate the different types of machining errors before and in machining of free-form surfaces, which can realize the targeted prediction and active compensation of machining error. First, the changing rule of cutting geometry conditions in machining of free-form surfaces is studied, and the flexible cutting force model of ball-end milling cutter under variable cutting conditions is constructed. Secondly, the interaction mechanism between cutting force and low-rigidity tool deflection is explained, and the tool-workpiece contact feedback model based on tool deflection is established. The iterative algorithm about the balance between the cutting force and tool deflection is developed to solve the tool deflection under the cutting balance condition. Thirdly, the mapping model between cutting force and machining error based on the optimized neural network is constructed to predict the steady error under the nominal tool trajectory. By means of decomposing machining error and first correcting of the NC programs, the off-line compensation of machining error can be realized. Finally, the mapping model between cutting power and machining error, as well as the representation model of cutting power based on spatial data similarity, are constructed. By means of prediction of transient error and the second modification of NC programs, the forward-looking process compensation of machining error can be carried out. The project is benefit to improving the manufacturing level of large deep cavity injection molds in China.