Natural calamities, such as landslides and flood, are very common in Japan due to heavy rains, earthquake and volcanic activities. The prompt response to those natural disasters reckon on the deployment of construction machines and equipments for search and rescue, assistance, assessment of damages, etc. In these cases, unmanned robots are the preferred choice, as they minimize the risks involved with secondary damages. The primary aim of the ImPACT Tough Robotics Challange project was to develop the required technologies needed to employ unmanned robots in disaster response. Within the scope of this project, the work herein presented focused on remote operation technology of construction robots. Specifically, it highlights the strategy designed for ensuring safe behaviors and remote visualization for unmanned construction robots.