Robotic Pellet Extrusion: 3D Printing and Integral Computational Design

3D printing offers significant geometric freedom and allows the fabrication of integral parts. This research showcases how robotic fused deposition modeling (FDM) enables the prefabrication of large-scale, lightweight, and ready-to-cast freeform formwork to minimize material waste, labor, and errors in the construction process while increasing the speed of production and economic viability of casting non-standard concrete elements. This is achieved through the development of a digital design-to-production workflow for concrete formwork. All functions that are needed in the final product, an integrally insulated steel-reinforced concrete wall, and the process for a successful cast, are fully integrated into the formwork system. A parametric model for integrated structural ribbing is developed and verified using finite element analysis. A case study is presented which showcases the fully integrated system in the production of a 2.4 m tall x 2.0 m curved concrete wall. This research demonstrates the potential for large-scale additive manufacturing to enable the efficient production of non-standard concrete formwork.