基于模态柔度的机床结合部动态刚度正交优化方法  

Orthogonal Optimization Method of Dynamic Stiffness of Machine Tool Joints Based on Modal Flexibility

作　　者：孙明楠[1] 殷国富[1] 胡腾[1] 

机构地区：[1]四川大学制造科学与工程学院,四川成都610065

出　　处：《四川大学学报（工程科学版）》2013年第4期90-96,共7页Journal of Sichuan University (Engineering Science Edition)

基　　金：科技部科技重大专项课题资助项目(2012ZX04011-031)

摘　　要：针对合理分配机床结合部动态刚度的需要,提出一种基于模态柔度理论的机床结合部动态刚度优化方法。该方法通过计算机床各阶模态柔度比判定对机床动态特性影响显著的薄弱模态,建立以几个薄弱模态的最小模态柔度为目标函数的多目标优化模型。为提高优化计算效率,引入了灰色系统理论中的灰关联分析法与正交试验设计。以1台精密卧式加工中心为例,将该方法应用于立柱-主轴系统分布的直线导轨、滚珠丝杠和螺栓结合部动态刚度的优化设计,识别出X向直线导轨结合部动态刚度对机床动态特性影响最为显著,并确定了1组结合部动态刚度的最优解。数值仿真和试验结果验证了该方法的有效性与工程实用性。To satisfy the requirements of distributing the dynamic stiffness of machine tool joints,an optimization design method for dynamic stiffness of machine tool joints based on the theory of modal flexibility was proposed.Weak modes that had significant effects on dynamic characteristics of the machine tool were judged according to modal flexibility coefficients of those modes.The multi-objective optimization mathematical model was established,with the minimum modal flexibility of the weak modes being the objective functions.To increase the efficiency of optimum calculations,the orthogonal experiment design and the grey relational analysis（GRA） method were introduced.Taking a precision horizontal machining center as example,the method was applied to the dynamic stiffness optmization design of the linear guide,ball screw,and bolt joints of the column-spindle system.The linear guide joint in the X-axial direction was identified that it has the most significant influence on dynamic characteristics of the machine tool.The best solution of dynamic stiffness of joints was obtained.The effectiveness and engineering practicability of the proposed method were verified by the results of numerical simulation and experiments.

关 键 词：模态柔度 结合部 动态刚度 正交试验 灰关联分析 多目标优化 

分 类 号：TH113[机械工程—机械设计及理论] TG502[金属学及工艺—金属切削加工及机床]