High-precision three-dimensional laser measurement system by cooperative multiple mobile robots

This paper presents a high-precision three-dimensional laser measurement system of an architectural structure by cooperative multiple mobile robots. This system is composed of three mobile robots, that is, a parent robot and two child robots. The parent robot is equipped with a three-dimensional laser scanner, attitude sensor, total station, and auto-leveling device. On the other hand, the child robots are equipped with six corner mirrors. The parent robot moves and stops repeatedly, and measures a three-dimensional architectural shape using the equipped laser scanner at several positions. Meanwhile, the child robots also move and stop alternately, and act as mobile landmarks for the positioning of the parent robot. By replacing or newly installing several devices/mechanisms, the precision of the proposed system becomes incomparably higher than our previous system. We report the system achieves quite high accuracy of 0.03 0.05% of targets' size through indoor/outdoor experiments. We apply the proposed technique for the shape measurement system of tunnels under construction and verify that the accuracy of the developed system is as high as a conventional ground-fixed laser scanner.