SfM-MVSによる3Dモデルを用いたサンプリングモアレ法における変形計測誤差低減手法の提案

抄録

SfM-MVS (Structure-from-Motion / Multi-View Stereo) is a technique that can easily generate high-quality 3D models without the need for special equipment, making it suitable for various measurement applications. The authors have proposed a deformation measurement method in which frontal images with obstacles removed are generated from a 3D model, and the displacement distribution is measured using the sampling moire method. However, when 3D models are generated using SfM-MVS, slight variations in scale occur in each reconstruction, which can become a source of measurement error. To address this issue, an error reduction method is proposed that corrects the displacement distribution using the coordinate values of reference 2D gratings attached to a non-deforming fixed part of the structure in the 3D model. Experiments were conducted using a small beam specimen to apply the proposed method to deformation measurement. By correcting the model width using the reference 2D grating and correcting the overall scale of the 3D model using markers attached to the fixed part, it was confirmed that the measurement error was effectively reduced. Furthermore, experiments were carried out under conditions where obstacles were present, and it was confirmed that effective measurement results for beam deflection could be obtained.