Robotic 3D clay printing of prefabricated non-conventional wall components based on a parametric-integrated design

Abstract

3D Printing (3DP) techniques and materials applied in construction-scale are currently under constant investigation, with notable results published at research and experimental level. While their great importance has been discussed extensively, very scarce detailed research has been published on 3DP parameters that are incorporated into the design process at an early stage to assess their impact on 3D printing performance, focusing on geometric conformity aspects. This work aims to provide a comprehensive parametric design investigation, driven by 3DP parameters, related to infill and overhang control, which can enhance a deeper understanding of their use in construction scale of non-conventional wall components, placing emphasis on construction time performance minimization. To this end, the paper initially illustrates the development of a parametric-integrated algorithm for toolpath planning and 3DP control using an industrial robot, capable of being universally adjusted based on open-source extruders with small, medium and large nozzle diameters. In this study, earth and clay-based materials are chosen because of their lower environmental impact and recyclability compared to concrete-based materials. Secondly, important printing parameters for toolpath planning, robotic and nozzle control, as well as robotic printing time, are presented and discussed in detail through 3DP experimental tests and a non-conventional wall study. The correlation of parameters in the early stage of design allows the assessment of their effectiveness to be used in construction-scale of non-conventional geometries towards minimization of 3DP time performance.