Automatic Robotic Construction for Customisable Rammed Earth Walls

Rammed earth construction has long been operated as a manual process involving unsaturated loose soil compacted inside a formwork. Earth soil is a type of highly sustainable naturalistic raw material decomposable with minimum environmental impact, with diverse colour and properties along by default. In addition, the high thermal resistance and moisture-absorbing quality of rammed earth walls significantly benefit the passive environmental comfort of the established environment. However, the manual process of rammed earth construction is excessively time and labour-intensive and highly dependent on skilled workers. More importantly, the visual effects on the vertical surface have long been overlooked by designers and builders, which has the potential to fulfil the aesthetic variety of facades. However, distributing the earth material with various colours to the specific position hinges upon the advanced fabrication accuracy and skilled workers. This process is similar to working in a black box, where it is hard to evaluate and detect the fabrication situation. Therefore, to tap into the potential of rammed earth construction, this research aims to develop an automatic robotic system capable of constructing rammed walls with a customisable distribution of different soil layers precisely.