Adaptive and Automatic Luminance Control of Open-air Historic Underground Sites Using Smart Glass Based on Digital Twins and 3D Reconstruction

JIAYING ZHANG, Jeff Chak Fu CHAN, Helen H. L. Kwok, Jack C.P. Cheng

Abstract: The entrance of the semi-open underground site is susceptible to sunlight, resulting in a significant green biological infestation that compromises the aesthetics and structural integrity of the historical site. The glass shed at the entrance of site provides light transmission and rain preservation. Traditional glass cannot simultaneously transmit and reflect light. To address this issue, a novel intelligent glass control system based on digital twin technology was developed. This system effectively regulates the illuminance within the prescribed range, ensuring the preservation of semi-open underground monuments. However, previous reconstruction methods struggle with non-homogeneous and complex morphologies. An improved 3D Gaussian Splatting algorithm-based method was proposed for fast and accurate 3D reconstruction, enhancing mesh completeness for numerical simulations. Furthermore, the digital twin-based smart glass system offers natural lighting while inhibiting plant growth, facilitating automatic, adaptive lighting control for heritage sites. The system’s effectiveness was illustrated in the former Sham Shui Po Service Reservoir.