基于逆有限元法的结构位移与应变场反演方法  

Inversion method of structure displacement and strain field based on iFEM

作　　者：岳应萍 吴国庆[2] 蒋镇涛 曾捷[1] 朱清峰 陈国材 YUE Yingping;WU Guoqing;JIANG Zhentao;ZENG Jie;ZHU Qingfeng;CHEN Guocai(State Key Laboratory of Mechanics and Control of Mechanical Structures,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,China;China Ship Scientific Research Center,Wuxi 214082,China)

机构地区：[1]南京航空航天大学机械结构力学及控制国家重点实验室,江苏南京210016 [2]中国船舶科学研究中心,江苏无锡214082

出　　处：《传感器与微系统》2024年第7期114-117,共4页Transducer and Microsystem Technologies

基　　金：基金资助项目(52275536);直升机旋翼动力学国家级重点实验室基金资助项目(61422202207);航空科学基金资助项目(20200009023017)。

摘　　要：舰船梯形结构作为封盖船体或将其分隔成层的平面板状结构,对于保证船体强度及不沉性具有重要作用。梯形结构受力不均匀会产生巨大拉扯力,易造成梯形结构变形与疲劳应力集中。基于此,本文提出研究一种基于逆有限元法(iFEM)和光纤应变感知的舰船梯形结构位移与应变场反演方法,并给出了相应光纤Bragg光栅(FBG)传感器布局形式。利用Ansys有限元分析方法,开展了基于仿真结果的相关反演方法验证。在此基础上,构建了基于光纤传感器的梯形结构位移、应变分布监测与反演实验系统。研究表明,双端固支梯形结构的位移重构均方根误差(RMSE)为0.076,应变场重构平均相对误差为6.59%。本文所提方法突破了iFEM因形函数阶次低而无法直接求解结构应变场的难题,能够为舰船梯形结构健康监测与舰载武器基座位姿精度提升提供技术支撑。As a plane plate structure to cover the hull or separate it into layers,trapezoidal structure plays an important role in ensuring the strength and unsinkability of the hull.Uneven stress of trapezoidal structure will produce huge pulling force,which is easy to cause deformation and fatigue stress concentration of trapezoidal structure.Based on this,an inversion method of displacement and strain field of ship trapezoidal structure based on inverse finite element method(iFEM)and fiber strain sensing is proposed,and the corresponding layout of fiber Bragg grating(FBG)sensors is given.By using Ansys finite element analysis method,the verification of relevant inversion methods based on simulation research is carried out.On this basis,the displacement and strain distribution monitoring and inversion experimental system of trapezoidal structure based on optical fiber sensor is constructed.The research show that the root mean square error(RMSE)of displacement reconstruction for double end fixed support trapezoidal structure is 0.076,and the average relative error of strain field reconstruction is 6.59%.The proposed method breaks through the difficult problem that the iFEM can not directly solve the structural strain field due to the low order of the shape function,and can provide technical support for the health monitoring of the ship trapezoidal structure and the improvement of the position and attitude precision of the shipborne weapon base.

关 键 词：逆有限元法 梯形结构 光纤BRAGG光栅传感器 位移 应变场反演 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置]