多目标优化在大型加工中心轻量化设计中的应用

Application of Multi-objective Optimization Design in Lightweight Design for Machining Center

为保证某大型加工中心的加工精度和切削效率,以其关键部件立柱为例,提出以质量及一阶固有频率为多目标优化的机床轻量化设计方法。首先根据有限元法利用有限元分析软件ABAQUS对立柱进行动静态特性分析,根据立柱结构分析提取影响1阶固有频率与质量的关键因素。通过均匀试验设计,利用MATLAB建立目标与关键因素的多元线性回归方程并进行灵敏度分析,找出敏感性因素。运用响应面法建立敏感因素与目标的2阶响应面数学模型,进而建立以减轻质量与提高固有频率为目标的立柱优化模型,最后应用MATLAB对数学模型进行优化求解。立柱经过优化后,提高立柱固有频率的同时质量减轻13.6%。

In order to ensure the machining accuracy and cutting efficiency of a machine center, taking the column of the machine center as an example, a multi -objective optimization design method in lightweight design for machining center is proposed in this paper, based on the mass and first natural frequency objectives. First of all, the element anal- ysis software - ABAQUS is utilized to analyze the static and dynamic performances of the column. And then according to the column structure, the key factors affecting the first natural frequency and the mass should be extracted. Through the uniform design, MATLAB is used to establish the multiple linear regression equations between the goals and the key fac- tors. At the same time, sensitivity analysis is conducted to find out the sensitivity factors. The targetg second order re- sponse surface mathematical model is built between the goals and sensitive factors by using the response surface method, and then the optimization model of column is set up with the purpose of reducing the mass and improving the natural fre- quency. Finally, the MATLAB is applied to optimize the mathematical model. As a conclusion, the mass is reduced by 13.6% under the condition of the improvement of the natural frequency.