薄壁件加工变形控制快速仿真平台开发

Fast simulation platform on machining deflection control of thin-walled workpiece

为控制薄壁件装夹变形和加工变形,建立了集装夹优化、加工变形预测、切削参数优化及误差补偿功能为一体的快速仿真平台。在平台实现中,装夹方案的优化采用基于形位公差控制的方法,通过多种装夹方案的比较,确定优化方案。加工变形预测时考虑了前一层变形对后一层切削深度的影响,并使切削力和加工变形达到动态平衡。为获得优化切削参数,建立了以变形控制为目标的优化模型,采用有限元法计算加工变形,采用遗传算法求解优化模型。为解得优化补偿量,仿真时考虑了变形与力的耦合效应。完成了基于ABAQUS的快速仿真平台开发。以镜座零件为例进行仿真,求得了优化的装夹方案和切削参数,验证了平台的可行性。

In order to control machining deflection force-induced of thin-walled workpiece, a fast simulation platform was introduced which integrated fixture optimization, deflection prediction, cutting parameters optimization and error compensation. In its implementation, various clamping schemes were compared based on error control and the optimal scheme was determined. The influence of machining deformation of the previous layer on nominal cutting depth of current layer was considered to achieve a dynamic equilibrium between the cutting force and deflection. To obtain optimal cutting parameters, an optimization model was proposed to reduce the degree of deformation. The finite element method was used to analyze the deformation and a genetic algorithm was developed to solve the optimization model. Compensation optimization by taking the coupling of deflection and machining force into account was realized to obtain the compensation values. The fast simulation platform based on ABAQUS was implemented and a specular seat was simulated. The simulation results showed that the platform was feasible to obtain optimal schemes or parameters.