Towards the automated virtual trial assembly of large and complex steel members using terrestrial laser scanning and BIM

Virtual Trial Assembly (VTA) is proposed as an alternative to physical trial assembly that can significantly reduce cost and time requirements. Existing studies on VTA can be categorized as total station and camera-based methods or Terrestrial Laser Scanning (TLS)-based methods. The real coordinate measurement procedure in existing total station and camera-based VTA methods is inefficient and complex because many targets have to be manually installed at assembly points and because different members require different installation schemes. Existing TLS-based VTA methods involve significant human intervention because assembly point extraction and assembly simulation are achieved with commercial software. In addition, geometric quality inspection is not performed in TLS-based VTA methods, although the basis for VTA is the dimensional quality compliance of the components. Therefore, this study presents an automated approach to perform VTA for large and complex steel members based on TLS, and Building Information Modeling (BIM) is utilized to provide as-designed geometric data. Specifically, an automated method is presented to extract assembly points. An internal point removal method is proposed for a BIM model to improve the accuracy of fine registration. A geometric quality inspection method is developed for bending and torsional deviation inspection. The proposed approach is found to be reliable through its application to a practical super high-rise building.