摘要
针对加工中心工作过程中变载荷铣削力对床身结构性能的影响问题,对加工中心床身的材料密度分布以及构成床身的基本结构单元尺寸进行了研究。提出了以床身低阶固有频率和最小柔度为目标,体积分数为约束条件的多目标拓扑优化设计方法;采用折中规划法结合平均频率法,构建了变载荷铣削力影响下的多目标拓扑优化数学模型;依据变密度法拓扑优化指导的材料去除方案,获得了加工中心床身的最佳结构布局;同时结合经过优化的拉丁超立方采样,构造了单元标准二阶响应面,使用多目标遗传算法对床身进行了多目标尺寸优化。研究结果表明:优化后床身固有频率增加16.9%,床身质量减少17.4%,最大变形量降低14.4%,最大应力降低18.8%;该优化方案使加工中心床身的结构布局更加合理,实现了轻量化设计。
Aiming at the influence of variable load milling force on the performance of the machine bed during the work of the machining center,the material density distribution of the machine bed and the basic structural unit size of the machine bed were studied.A multi-objective topology optimization design method was proposed,which aimed at the low-order natural frequency and minimum flexibility of the bed,and the volume fraction as the constraints.A mathematical model of multi-objective topology optimization under the influence of variable load milling force was constructed using the compromise programming method and the average frequency method.The optimal structure layout of the machining center bed was obtained according to the material removal scheme guided by the topology optimization of the variable density method.At the same time,the standard second-order response surface of the optimized Latin hypercube sampling construction unit was used to perform multi-target genetic algorithm on the bed optimized size.The results indicate that the natural frequency of the bed is increased by 16.9%,the mass of the bed is reduced by 17.4%,the maximum deformation is reduced by 14.4%,and the maximum stress is reduced by 18.8%.This optimization scheme makes the structural layout of the machining center bed more reasonable,and realizes lightweight design.
作者
梁丽强
萨日娜
高峰
LIANG Li-qiang;SA Ri-na;GAO Feng(Institute of Mechanical Engineering,Inner Mongolia University of Technology,Hohhot 010051,China;Institute of Mechanical Engineering,Zhejiang University,Hangzhou 310027,China;Canny Elevator Company Limited,Suzhou 215213,China)
出处
《机电工程》
CAS
北大核心
2020年第9期1013-1019,共7页
Journal of Mechanical & Electrical Engineering
基金
国家自然科学基金资助项目(51765052,51405247)
内蒙古自然科学基金资助项目(2016MS0507)
江苏省成果转化资金资助项目(BA2018083)。
关键词
变载荷铣削力
折中规划法
多目标拓扑优化
单元法尺寸优化
variable load milling force
compromise programming method
multi-objective topology optimization
element method size optimization
