Construction payment automation using blockchain-enabled smart contracts and robotic reality capture technologies

This paper introduces an autonomous payment administration solution, integrating blockchain-enabled smart contracts and robotic reality capture technologies. The construction progress is captured, analyzed, and documented respectively using sensing, machine intelligence, and as-built building information models (BIM). The progress data is stored in a distributed manner using content addressable file sharing; it is then broadcasted to a smart contract which administers payments and transfers lien rights respectively using crypto currencies/tokens and non-fungible tokens (NFT). The method was successfully implemented for payments to 7 subcontractors in two real-world commercial construction projects in Canada and United States where progress was captured using a camera-equipped unmanned aerial vehicle (UAV) and an unmanned ground vehicle (UGV) equipped with a laser scanner. The method eliminates reliance on today's heavily intermediated payment applications and showed promise for achieving accurate, efficient, and timely payment administration. Future work should further explore the connections between off- and on-chain realities.