3d Scanning Workflow Applied For Robotic 3d Printing On Complex Surfaces: Taking Advantages of A Digital Shadow For Robot Motion Path Generation and Geometric Control

A key challenge in robotic 3D printing (3DP) for the construction industry is upcycling existing elements to add new functionalities and improve structural performance, addressing the problem of digitally reconstructing physical elements. An accurate 3D model as a Digital Shadow (DS) enables real-time, one-way data transfer from reality to digital model for geometric adjustments, 3DP code implementation, and tracking shape reactions during manufacture. Traditional metal scanning methods often require time-consuming surface preparation and expensive hardware. This research proposes a workflow with two case studies: scanning for additive manufacture (AM) using Wire Arc Additive Manufacture (WAAM) and 3DP using Fused Deposition Modeling (FDM) on non-planar 1mm steel plates. These approaches are compared for effectiveness in generating a DS based on time and data. The first uses a low-cost depth camera for quick 3D model reconstruction. The second employs an off-the-shelf 3D scanner precise geometry control.