Mobile Additive Manufacturing: A Case Study of Clay Formwork for Bespoke in Situ Concrete Construction

The in situ production of concrete building components with Additive Manufacturing (AM) provides new possibilities in design and function. Current deployable solutions are often stationary gantry systems, which need to increase in size with the constructed object. This research aims to address this issue by using mobile robotic systems for in situ AM instead, which can manufacture structures that exceed their static work range. However, where stationary AM systems inherently exhibit a high level of accuracy, mobile AM systems must be context-aware through onboard sensing and therefore pose a significant research challenge in their deployment and operation. A case study is performed with a mobile AM system using a print-drive-print approach for the sequential fabrication of a 1:1 scale clay formwork of a bespoke, reinforced, and lightweight-concrete column, on which this paper presents first results. A two-tiered system is applied and validated, with initial global localization through 2D SLAM, and a second refinement relative to the work piece through a 2D scanner fitted at the end-effector.