Laser-based multimodal characterization allows quantitative modeling for fasteners

Laser triangulation scanning, digital holography and projection imaging have been used to perform characterization of fasteners. Thanks to the complementary characteristics of these methods, we demonstrate how laserbased fastener characterization can contribute to the digitization of physical components. Here, two experimental strategies are proposed to address the challenges of metal part characterization: laser triangulation based on round-trip scanning and hybrid digital holographic 3D modeling. By combining 3D projection measurement with unidirectional reciprocating motion, the missing information around the fastener area can be recovered. In addition, the combination of digital holography and projection imaging allows us to achieve digital modeling of millimeter-scale bolts with micron-level accuracy. These laser-based measurement technologies will further optimize standardization processes in modern industry.