Robotic Dry-Stacking of Clocháin with Irregular Stones

Abstract

This paper explores automated robotic construction of clocháin<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup>, a type of corbelled rock shelter, traditionally crafted by skilled workers. While robots have been employed for simple dry-stacking tasks in the past, such as construction of stone walls or vertical stone towers, the question of whether robots possess the capacity to construct more functional structures remains unanswered. This study presents a significant step forward in robotic dry-stacking of functional structures: the assembly of natural stones into freestanding clocháin structures. We also present a set of stackability measures to aid stone selection, which significantly improves the stability of the planned structures. Our sequential filtering approach, originally designed for planning stone walls, plays a foundational role in achieving stable clochán construction. Experimental results validate the effectiveness of the stackability measures and demonstrate the physical execution of dry-stacking clocháin, The progress demonstrated in this paper opens the door to robotic construction of a wide range of utility structures in unstructured environments.