Development of Automated Mobile Marking Robot System for Free Access Floor

Improvement of productivity in construction work is strongly required because a shortage of construction workers has become a major social issue in Japan. Marking work for installing building materials is indispensable. This work is currently carried out manually. If this work can be automated, construction workers can concentrate on installing the building materials. Therefore we intend to improve productivity by automating this work with a mobile marking robot system. For the first step, we developed the marking robot system for a free access floor. To build this, grid-pattern lines should be drawn on the floor. Our system can automatically mark the intersections of the lines which are the positions for installing pedestal base s of the free access floor. Our system consists of a mobile marking robot and a laser positioning unit. The former is a mobile robot which has the marking device at its center. Cross marks are drawn on the floor by controlling the marking device. The laser unit accurately directs the point and line laser in the target direction and measures the distance to the object on which the laser spot is projected. The marking robot tracks the line laser and arrives at the target area. The deviation between the target position and the robot center is calculated, and the cross mark is drawn exactly on the target position. This paper describes the mechanism of our system. It also shows the satisfactory tracking performance and marking accuracy in several experiments.