五轴联动加工中心动力学建模及质量匹配优化

Dynamic Modeling and Quality Optimization of Five-axis Machining Center

为了解五轴联动加工中心结构件质量对整机性能的影响规律,结合集中参数法和子结构综合法建立整机动力学模型。依据五轴联动加工中心拓扑结构特点,基于子结构综合思想,将其分为两个拓扑子链并分别开展影响规律分析;基于结构件间的质量关系,提出了机床质量匹配度的评价指标-结构件质量比(RT)。通过分别对刀具链和工件链中结构件质量进行匹配优化,获得整机的质量匹配优化方案,并基于有限元仿真软件对优化结果进行验证。结果显示,通过该优化方法,整机质量减轻10.3%,整机首阶固有频率提高3.9%。

Aiming to reveal the influence rules of the parts′masses of five-axis machining center on the whole machine performance,the dynamic model for the five axis machine center was established by combining the centralized parameter method and the substructure,According to the characteristics of topological structure of five-axis machining center,and the idea of substructure synthesis,it is divided into two sub-chains.Furthermore,the influence law is carried out.After analyzing the relations of each part′mass of the sub-chain assembly,the evaluation index of machine tool inertia matching-mass ratio is proposed.Based on the optimization result of the inertia matching of tool-chain and part-chain,the mass optimization scheme of the whole machine is obtained.The optimization result is verified by the finite element simulation software.The results show that the mass of the whole machine is reduced by 10.3%and the first-order natural frequency is increased by 3.9%.