磁悬浮控制力矩陀螺框架结构的拓扑优化设计

建立磁悬浮控制力矩陀螺框架结构的有限元分析模型,对控制力矩陀螺框架结构进行模态分析,阐述了框架结构优化设计的基本思路.结合双向渐进优化算法拓扑优化理论,基于通用有限元分析软件ANSYS的参数化设计语言和二次开发语言,开发了连续体拓扑优化模块.以框架结构的最低阶频率值为约束条件,以框架结构质量最小为优化目标,引入名义应力的概念,建立框架结构固有振型与名义应力的关系,实现了磁悬浮控制力矩陀螺框架结构的动态拓扑优化,扩展了双向渐进优化算法的应用范围.优化后的结构构型具有更为合理的质量和刚度布局,频率提高11.49%,质量减少5.65%.

Topology optimization design of frame structure for magnetic suspension control moment gyroscope

The finite element model of frame structure for magnetic suspension control moment gyroscope (MS-CMG) was established and a modal analysis was implemented. On the view of the numerical results the optimization opinions of the frame structure were presented. The topology optimization module for continuum structure was developed and plugged in ANSYS via its APDL and UIDL combined with the bi-directional evolutionary structural optimization method (BESO). Thus the dynamic topological optimization of frame structure was realized with the fundamental frequency as constraint condition and the minimum weight as the target function. In this procedure, a nominal stress was presented and a relationship between the nominal stress and the corresponding mode shape of frame structure was established, by which the BESO was extended to apply in field of dynamic optimization. At last, a frame structure configuration was provided with optimum layout of stiffness and mass was given. Comparing with the initial configuration, the optimum frame structure satisfied the design demands and the fundamental frequency increased by 11.49%, whereas the mass decreased by 5.65%.