二维分布式光纤形状传感应变传递研究

Research on strain transfer of two dimensional distributed optical fiber shape sensor

为分析光纤分布式形状传感器结构中基底与光纤在应变时的传递率,研究层合式结构模型各层之间耦合影响,建立了涂布层—胶结层—传感层三层应变传递模型。通过分析结构微元段,构建应变传递变化函数,推导出光纤应变传递关系。结合有限元仿真结果,验证了模型的有效性。结果表明:结构中间区域应变传递率为1,两端逐渐减小。在实验与应用中,选用弹性模量为4 GPa,泊松比为0.38的胶粘剂粘接半径为1 mm;涂布层选用弹性模量为2 GPa,泊松比为0.3,厚度半径为10 mm的材料,可有效提高应变传递率,减小检测误差。为提高形状检测技术精度提供理论依据。

In order to analyze the strain transfer rate between substrate and optical fiber in optical fiber distributed shape sensor structure,the coupling effect between layers of laminated structure model is studied.And a three-layer strain transfer model for coating layer-protective sheath layer-sensing layer is established.By analyzing the structural micro elements,the strain transfer function is constructed,and the strain transfer relationship of optical fiber is deduced.Combined with the finite element simulation results,the effectiveness of the model is verified.The results show that the strain transfer rate in the middle region of the structure is 1 and decreases gradually at both ends.In the experiment and application,the adhesive with elastic modulus of 4 GPa and Poisson’s ratio of 0.38 is used to bond radius of 1 mm;the coating layer is made of materials with elastic modulus of 2 GPa,Poisson’s ratio of 0.3 and thickness radius of 10 mm,which can effectively improve the strain transfer rate and reduce the detection error.It provides a theoretical basis for improving the precision of shape detection technology.