数字光弹性中材料条纹常数的自动确定  

AUTOMATIC DETERMINATION OF FRINGE CONSTANT IN DIGITAL PHOTOELASTICITY

作　　者：雷振坤[1] 云海[2] 赵燕茹[3] 潘学民[4] 

机构地区：[1]大连理工大学工程力学系工业装备结构分析国家重点实验室,辽宁大连116024 [2]山东理工大学交通与车辆工程学院,山东淄博255049 [3]内蒙古工业大学理学院,内蒙古呼和浩特010051 [4]大连理工大学材料系,辽宁大连116024

出　　处：《工程力学》2009年第12期40-45,51,共7页Engineering Mechanics

基　　金：国家自然科学基金项目(10502014;50704009);工业装备结构分析重点实验室项目(S08206)

摘　　要：材料条纹常数是光弹性实验的一个关键参数,也是联系力学量和光学量的纽带,要求具有较高的标定精度。在线性最小二乘法的基础上,该文提出一种自动化确定光弹性材料条纹常数和对径压缩圆盘中心位置的方法。使用相移光弹性法得到对径压缩圆盘全场等色线级数作为实验数据,利用最小二乘法建立超定非线性方程组,最后通过牛顿迭代法求解来自动确定光弹性材料条纹常数和圆盘中心位置,并进行了实验验证。A nonlinear least-squares method was applied to determine the photoelastic fringe constant from isochromatie phase field obtained by digital phase-shifting photoelasticity. To perform automatic evaluation, the photoelastic fringe constant and the center coordinates of a disk under diametral compression are determinated simultaneously using the nonlinear least-squares method. A set of over-determinated nonlinear equations are obtained to estimate the unknown parameters by an iterative procedure based on Newton-Raphson method. Experimental result shows that the parameters are evaluated accurately from the isochromatic phase field obtained from the six-step phase-shifting photoelasticity. The photoelastic fringe constant and the disc center coordinates can be evaluated easily, simply and automatically by the technique.

关 键 词：光弹性材料条纹常数 最小二乘法 牛顿迭代法 超定非线性方程组 数字光弹性 

分 类 号：O348.1[理学—固体力学] O438[理学—力学]