A Parametric Wave Joint for Robotic Fabrication of Digital Stereotomy

This paper explores the potential of digital stereotomy in combination with robotic fabrication to increase the precision and complexity of stone processing. To enable the application of these techniques in outdoor environments, modular joints designed for robotic assembly are necessary. Additionally, the cutting process must be efficient and minimize material waste. To address these challenges, this research proposes a parametric wave joint design that enables rapid cutting and straightforward assembly by a robotic system. The joint contains motion space allowing it to slide into accurate assembly position, enabling the robot to complete the assembly without requiring highly precise vision or gripper in outdoor situations. Furthermore, the wave joint design eliminates the need for milling, reducing the processing time. The paper presents a robotic arm-cutting method for this joint and conducts experiments using foam and robotic arm hot-wire cutting to simulate stone cutting. The feasibility of the joint is tested through the assembly of a bent column, and finite element analysis is used to compare the stresses on two joint parts under shear force with different control parameters. The study confirms the feasibility of the wave joint design for robotic assembly and the efficiency of robotic arm cutting. The findings may inform the development of modular assemblies for robotic systems in stone processing applications.