An autonomous excavator, so without a human, has built the stone wall.
The aim of the ETH research project Mobile Robotic Aggregation of Found Objects is to autonomously construct structures, such as walls and columns using found and readily available materials such as waste concrete and stones. The process uses a robotic excavator HEAP (Hydraulic Excavator for an Autonomous Purpose), a customized Menzi Muck M545 12t that can walk. This excavator is currently the most advanced robotic excavation platform to be applied to complex construction tasks.
Building with locally sourced boulders and waste concrete has the potential to drastically reduce the environmental carbon footprint of construction. In Switzerland, we have many dry-stone masonry walls but they are very hard to build. They have historically been widely utilized for walls and terracing in the mountains.
This project demonstrates that computational methods, machine vision, and new control methods can be used to build with rocks that have many different shapes. The wall could be deconstructed and all the rocks re-used, so it produces very little waste.
The permanent retaining wall at the EbiMIK park represents the largest demonstration of this method: the structure is 65 meter long, 6 meters tall at its apex, and consists of 938 (boulders and concrete demolition debris. The boulders have an average mass over 1000 kg each. So this wall is among the largest robotically fabricated structures in existence!
