基于MFC的结构静态形状控制研究

Research on static shape control of structures based on MFC

宏纤维复合材料MFC(Macro Fiber Composite)具有体积小、主动控制适用性强、作动效果好等特点。本文开展了宏纤维复合材料MFC对结构静态形状主动控制研究。建立了悬臂梁结构有限元模型,并采用载荷比拟法计算得到了MFC压电作动器的驱动载荷。基于数值分析结果,搭建了悬臂梁结构主动控制实验平台,分析了不同加载电压下的悬臂梁的弯曲变形效果,进而分析MFC结构在静态形状控制中的力学性能。数值仿真和实验结果表明:在不同的静态电压加载下,结构的变形和加载电压近似呈线性关系;仿真和实验结果对比中呈现出较好的一致性,其最大位移误差为12.45%。最后讨论了MFC压电作动器自身时间蠕变特性对静态变形控制实验结果产生的影响,结果表明在大电压作用下MFC材料存在蠕变效应,在实际使用过程中需要关注。本文采用以悬臂梁为载体的实验和仿真研究方法对在其他横观各向同性材料的压电材料力学性能分析具有普遍适用性。

Macro Fiber Composite(MFC) provides good characteristics of small-sized, strong applicability in active control and good accuracy in actual motion. In this paper, the active control of static shape of MFC is studied by experimental and numerical analysis. The finite element model of cantilever beam is developed and simulated by load analogy method to achieve the driving force of MFC piezoelectric actuator. The corresponding active control experimental platform is built up on the basis of numerical model. The bending deflections of cantilever beam are analysis under different static voltage loads. The mechanical characters of static shape control of MFC are obtained via experimental and numerical results. The deformation of the cantilever beam is approximately linear with the variations of static voltage loads. The good consistency is observed and maximum error is 12.45%. Finally, the influence of creep characteristics of MFC piezoelectric actuator on the static deformation control is analyzed. Special attentions related to the creep effects of MFC should be paid during its industrial applications. The present cantilever beam form based experimental and numerical methodology has the universal applicability to the analysis of mechanical properties of other transversely isotropic piezoelectric materials.