Koji-Gumi Operates Remote-Controlled Excavator and Autonomous Dump Truck With One Worker at Hiroshima Erosion-Control Project

prtimes.jp reported on October 29, 2026, that Koji-Gumi operated a remote-controlled excavator and an autonomous dump truck with one worker at an erosion-control project in Hiroshima. We have not verified the primary source, so readers should consult the original report for details.

Koji-Gumi says it eliminated workers from the hazardous area and had one person handle excavation and hauling work that had previously required two. Whether staffing can be reduced while maintaining safety is a concrete challenge in applying remote and autonomous construction at steep, confined erosion-control sites.

The key point is not simply the introduction of remote control and automation, but that one person combined two types of construction equipment with different operating methods at a steep, confined erosion-control site. The reported achievement of having one person handle excavation and hauling work that previously required two can be seen as an effort to change how the work is organized from excavation and loading through transport, rather than merely automating individual machines. However, the 50% reduction in labor and 32% increase in productivity are figures Koji-Gumi announced for this demonstration; they do not show that similar results would be achieved at other sites or for other types of work. Technically, the system links site assessment to machine control by using drone point-cloud data to define areas where vehicles can travel, then detecting obstacles and stopping while in motion. The operating plan also uses a Mobility Office as the control base, with one person operating a remote-controlled excavator and an autonomous dump truck. Unlike a test that checks only autonomous driving on flat ground, this demonstration examines whether the approach can work at a confined, active construction site, including staffing, safety management and communications. EARTHBRAIN says this is its first autonomous construction project in Japan at a sloped erosion-control site, but the scope should be understood in the context of the conditions described in the announcement. In terms of construction-site automation, the factory operations described in Nikkei Business reports on Komatsu’s “almost fully unmanned” factory, with working hours cut by 90% involve different processes from this project, which mechanizes work at a construction site. Reductions in factory work hours cannot be compared on the same scale with labor savings at erosion-control sites, where terrain and communications conditions vary. The project also differs in its data and setting from the cross-manufacturer manufacturing-data collection plan described in Nikkei reports that government, DMG Mori and Komatsu plan to cooperate on data collection for physical AI. The announcement says construction data and know-how will be shared, but does not explain how they will be used for coordinated work by multiple machines or for retraining. Assessing practical viability will require checking how false obstacle detections affected work stoppages and hauling efficiency, and whether safety stops reliably activate when communications are unstable. The announcement did not provide figures for operating hours, transported volume, number of stops or implementation costs. Koji-Gumi has proposed operating multiple autonomous dump trucks and having one person manage three to four or more machines, but the next issue is how safety and work volume will be evaluated through phased demonstrations.