基于B样条拟合的光纤光栅机敏柔性结构形态重构

Shape reconstruction of FBG intelligent flexible structure based on B-spline fitting

研究了细长机敏柔性结构的三维形态拟合与重构方法以实现高性能飞行器结构形态主动监测。首先,介绍B样条曲线拟合基本原理,分析基于正交曲率信息的空间三维曲线重构算法和实现步骤,并进行了数值仿真分析;构建了机敏结构模型和实验环境,基于Visual C++平台和OpenGL技术开发了可视化软件;然后,描述正交分布式光纤光栅传感阵列曲率检测方法,分析与验证了实验模型结构的三维空间形态拟合与重构实验;最后,采用B样条与线性插值两种拟合算法分别对半径为50 cm的标准圆形态进行坐标拟合和对比。实验结果表明,B样条拟合算法具有更好的拟合重构效果,其拟合坐标标准差是线性插值拟合算法的40%。光纤光栅机敏柔性结构空间形态重构与可视化效果良好,验证了B样条拟合算法的高精度和低误差特性。

Three-dimensional curve fitting and reconstruction of an intelligent structure shape were researched to implement the active monitoring for a high-performance aircraft structure shape.Firstly,the B-spline curve fitting method and recursive algorithm for coordinate fitting were introduced,and algorithm processes and implementation steps as well as numerical simulation analysis were presented.Then,a flexible structure model and its experimental environment were established,and visualization software was developed based on the Visual C＋＋ and OpenGL technology.Furthermore,the curvature detection principle of the orthogonal distributed Fiber Bragg Grating（FBG） sensor array was demonstrated,subsequently,the three-dimensional space shape fitting and reconstruction of the experiment model structure were analyzed and verified.Finally,B-spline fitting algorithm and linear interpolation algorithm were adopted separately to construct a standard circle with the radius of 50 cm.Experimental results show that B-spline fitting algorithm has better graphical reconstruction effects comparing with linear interpolation algorithm,and its standard deviation is 40% that of linear interpolation.As the FBG intelligent flexible structure shows the better shape reconstruction and visualization,it verifies the high precision and low error characteristics of the B-spline algorithm.