Robot-based installation of nanostructured metal multilayers on civil infrastructure

Fatigue, particularly in welded joints, causes premature failure of civil infrastructure, an increase in maintenance costs, and safety risks. Nanostructured metal multilayers, applied via electrodeposition, represent a novel treatment to enhance the fatigue strength of welded joints by introducing residual compressive stress during the deposition process, reducing surface roughness and strengthening resistance against extrusions. Nanostructured metal multilayer (NMM) patches may be utilized to postpone crack initiation, restrict the propagation of structural damage, and prolong the life of civil infrastructure. With advancements in robotic technologies, automated robot-based processes may be employed to ensure accuracy and consistency when installing nanostructure patches. In this paper, a methodology for automated robot-based installation of NMM patches on welded joints of civil infrastructure is proposed. Mobile robots, equipped with robotic arms, autonomously navigate to welded joints and install NMM patches using electrodeposition. To validate the methodology, NMM patches are installed and tested under laboratory conditions in small-scale experiments. As a result, integrating NMM technology and robot-based automation, presented in this study, demonstrates a promising approach towards prolonging the lifetime of civil infrastructure.