基于条纹投影的复杂结构多维度信息传感技术(内封面文章·特邀)

Multi-dimensional information sensing technology of complex structures based on fringe projection(inner cover paper·invited)

随着精密加工和智能制造业的高速发展,在航空航天、汽车工业、工业检测等领域中,对复杂结构,例如:发动机组件、蜂窝结构件等在生产制造与使用过程中的形貌、形变及应变等多维度信息的测量需求日益增加。最近兴起的数字图像相关辅助条纹投影技术已被证明在复杂结构的形貌和形变测量方面具有独特优势。但目前由于两类方法各自不同的技术特点,基于两者结合的形貌、形变测量方法在测量精度、效率等方面存在诸多矛盾,难以兼顾高分辨率、多维度的测量需求,阻碍了该类技术进一步拓展应用。综述了课题组近年来发展的基于条纹投影的复杂结构多维度信息传感技术及最新的研究进展,系统回顾了两类方法结合时的条纹与散斑信息干扰、原始纹理被破坏、编码效率低等技术难点,并总结了对应的解决方案,最终实现了对复合材料编织结构、颗粒膨胀减震结构以及层叠结构等复杂结构的多维度信息传感。文中所提方法在不增加额外硬件的前提下,将传统条纹投影测量系统升级为多维度信息传感系统,可以同时测量2D纹理(T)、4D形貌(x,y,z,t)以及分析维度力学参数(形变d和应变s),突破了复杂结构高分辨率、高精度纹理形貌重建与形变应变分析的技术壁垒,有望在复杂结构可靠性分析、复合材料性能评估等领域中得到应用。

Objective With the rapid development of precision machining and smart manufacturing,there is an increasing demand for multi-dimensional information,including the shapes,deformations,and strains of complex structures like engine components and honeycomb structures,during their production and usage across fields such as aerospace,automotive industries,and industrial testing.The recently emerging digital image correlation-assisted fringe projection technology has demonstrated unique advantages in measuring the shape and deformation of complex structures.However,due to the distinct technical characteristics of these two methods,combining them for shape and deformation measurement presents several challenges in terms of measurement accuracy and efficiency,making it difficult to meet high-resolution and multi-dimensional measurement requirements,thus hindering the further application of this technology.This study reviews a multi-dimensional information sensing technology for complex structures based on fringe projection,developed by the research group in recent years,along with the latest research progress.It systematically revisits the technical challenges encountered when combining the two methods,such as fringe and speckle information interference,destruction of the original texture,and low encoding efficiency,and summarizes the corresponding solutions.Ultimately,it achieves multi-dimensional information sensing of complex structures such as composite woven structures,particle expansion damping structures,and laminated structures.The proposed solution upgrades the traditional fringe projection measurement system into a multi-dimensional information sensing system without additional hardware,enabling simultaneous measurement of 2D texture(T),4D shape(x,y,z,t),and mechanical parameters related to analytical dimension(deformation and strain).This breakthrough overcomes technical barriers to high-resolution,high-precision texture shape reconstruction and deformation-strain analysis of complex structures,and is expected to find applications in the reliability analysis of complex structures and the performance evaluation of composite materials.Methods The multi-dimensional information sensing method based on the FPP system involves creating highly reflective and vivid fluorescent speckles on the surface of the object and then efficiently encoding the pattern using a structured light interlacing method to enhance projection efficiency.High-quality stripes,textures,and speckle information are then separated from the captured images using a general information separation method,providing accurate original data for subsequent deformation analysis.The shape data is matched,and three-dimensional displacement is calculated using DIC.Finally,deformation is further analyzed using the chained strain analysis to improve calculation efficiency.This provides a comprehensive technical solution for combining FPP and DIC,suitable for complex dynamic scenes(Fig.6).Results and Discussions The measurement results of woven structures and standard balls show that the strength-chromaticity information separation method performs better in terms of phase accuracy,speckle quality evaluation functions SSSIG and MIG compared to the other two traditional integration methods(Fig.14-15).By comparing the shape reconstruction of honeycomb structures and woven structures with 3D-DIC,the proposed method can better obtain shape data for complex regions(Fig.16-Fig.17).Additionally,better shape data can further guide sub-region division,especially for sub-regions that are difficult to observe in images and have discontinuities,which can be improved by depth constraint to enhance deformation analysis accuracy(Fig.18).Finally,compared to 3D-DIC,the multi-dimensional information sensing method based on the FPP system has lower computational time and hardware cost(Fig.19).These comparative experiments verify the superiority of the proposed system.Conclusions The three-dimensional shape measurement technology based on fringe projection has been widely used in industrial inspection,cultural heritage preservation,intelligent driving,and other fields due to its high speed,accuracy,and full-field measurement capabilities.It has become a research hotspot in both scientific and engineering fields.To further enhance the application of fringe projection in the analysis of mechanical properties,researchers have proposed the DIC-assisted FPP technology,conducting extensive research in multiple areas.This study delves deeply into key technical issues such as the reconstruction of complex,high-noise surface topography,high-quality information separation,and accurate deformation and strain calculation within existing combined methods.The proposed methods have been experimentally validated by the research team,showing advantages in information separation capability,handling complex region topography,analyzing fracture region deformation,computational efficiency,and hardware cost.The multi-dimensional information sensing method based on the FPP system upgrades the existing hardware structure into a multi-dimensional measurement system,breaking through technical barriers in high-precision,high-resolution topography reconstruction and deformation and strain analysis of complex surfaces.The successful application of this technology in complex structures demonstrates its great potential in analyzing complex structures and fracture regions,and it is expected to be widely used in aerospace,the automotive industry,biomedicine,and other fields.