It is a well-known fact that Japan saw an annual average economic growth rate of over 10% from around 1955 to around 1973, its so-called “high-economic-growth period.” Japan’s rate was two to four times higher than that of Europe or the United States. During this period, Japan’s infrastructure (roads, bridges, tunnels, etc.) was rapidly developed nationwide, bringing Japan’s national average road pavement ratio in 2017 to over 80%, one of the highest rates in the world. Such rapid infrastructure development has made all of Japan a comfortable place to live. However, as Japan’s infrastructure is now becoming increasingly deteriorated, the structures nationwide must be inspected for soundness and should be repaired or rebuilt if any defects are found. As these structures are highly developed, the number of structures to be inspected becomes so numerous that the human-based inspection cannot keep up.

This situation has led to growing calls for artifact inspection systems that carry out inspection work more efficiently, and the Cross-ministerial Strategic Innovation Promotion Program (SIP) was established, one of which is “Infrastructure Maintenance, Renovation and Management,” with Yozo Fujino as Program Director (SIP Infrastructure), having been implemented for five years since fiscal year 2014.

This Special Issue on Infrastructure Maintenance and Inspection Robotics has collected papers that propose a broad range of infrastructure maintenance/renovation/management technologies, especially those developed by SIP Infrastructure, in order to contribute to the further development of the field of infrastructure maintenance and inspection technologies.