基于冗余应变信息的逐点抑噪算法  

Pointwise Noise Suppression Algorithm Based on Redundancy Strain Information

作　　者：涂文戈 黄祖桂 郭玉荣[1] Tu Wenge;Huang Zugui;Guo Yurong(Key Laboratory of Building Safety and Energy Efficiency,Ministry of Education,College of Ciril Engineering,Hunan University,Changsha,Hunan 410082,China)

机构地区：[1]湖南大学土木工程学院建筑安全与节能教育部重点实验室,湖南长沙410082

出　　处：《激光与光电子学进展》2021年第24期289-300,共12页Laser & Optoelectronics Progress

基　　金：国家自然科学基金(51878259)。

摘　　要：在数字图像相关方法中,光噪声和电子设备噪声等因素会影响应变场的计算精度。基于单点的冗余应变信息提出利用概率密度函数或者构造指数权重函数,通过加权求和逐点抑制应变场中的噪声。将该方法运用于逐点最小二乘法识别了模拟数字散斑图像仿真实验,带孔板拉伸实验和带裂缝的钢筋混凝土柱的受弯实验的应变场。结果表明:相较于经典的逐点最小二乘法,在均匀变形情况下,本文方法能够有效提高应变场精度;当两个方法获得相同精度的应变场时,本文方法的计算速度提高了65%以上;在裂缝附近,本文方法能够获得更可靠的应变值,适用范围更广;相较于基于正则化平滑的有限单元应变方法,本文方法的计算精度更高,而且计算速度更快。Factors such as optical noise and electronic device noise can affect the accuracy of the strain field in the digital image correlation method. This paper introduces an algorithm based on single-point redundant strain information. This algorithm suppresses noise in the strain field through weighted summation using a probability density function or constructing an exponential weight function. In the pointwise least squares method, this proposed algorithm is used to identify the strain field of the computed-simulated speckle images test, the tensile test of a plate with one hole, and the bending test of a reinforced concrete column with cracks. The results show that in the case of homogeneous deformation, compared with the classical pointwise least squares algorithm, the accuracy of the strain field calculated by the proposed method has been effectively improved;while both methods achieve the same precision, the calculation speed of the proposed method by more than 65%. Moreover, the proposed method can obtain more reliable strain values in the region near the crack, giving it a broader range of application. Furthermore, compared the regularization-aided finite element strain calculation method, the proposed method has greater accuracy and a faster calculation speed.

关 键 词：测量 数字图像相关 应变场 权重函数 抑噪 

分 类 号：O348.1[理学—固体力学]