Vision-based 3D Deformation Reconstruction of a Composite–Wood Hybrid Structure under Transient Load Release

Abstract

Accurate reconstruction of complex structural deformation is essential for understanding transient mechanical responses in hybrid and multi-material systems. This study presents a vision-based approach for three-dimensional deformation reconstruction of a composite–wood hybrid structure subjected to transient load release. The investigated specimen consists of a U-shaped carbon-fiber-reinforced composite beam connected perpendicularly to a wooden cantilever beam, forming a configuration that exhibits strong coupling between bending and torsion during load removal. A single-camera imaging system was employed to capture the structural response throughout the release process. Surface motion was extracted from image sequences using feature tracking and temporal filtering techniques. Based on the known structural geometry and camera calibration parameters, the three-dimensional deformation field was recovered from single-view data. This method enables non-contact and full-field reconstruction without requiring embedded or attached sensors, making it well suited for hybrid or geometrically irregular structures. Preliminary experiments demonstrate that the proposed approach can effectively capture the evolution of deformation and reveal coupled twisting and bending behaviors during the transient release event. The reconstructed deformation patterns qualitatively agree with visual observations, highlighting the capability of single-view vision methods to characterize dynamic structural responses. The proposed framework provides a practical and low-cost solution for dynamic deformation monitoring of complex and multi-material structures. It underscores the potential of vision-based sensing as a valuable complement to conventional techniques in structural health monitoring applications where sensor deployment or accessibility is limited.