Development Of Positioning Systems For Autonomous Robots On Construction Sites

Construction is a potential field of applications for autonomous robots. For some years, experimental mobile robots have been developed, mainly in Japan, to perform various construction tasks. Our laboratory has developed, with french partners, the first european autonomous mobile robot for finishing work in buildings named "SOFFITO" , Autonomous manipulators are also on the way 1-0 ho dovclopod an well as oxcilvators or asacmbly manipulators for walls erection for instance. All these applications require at least one reliable real time positioning system. This point is essential and special efforts must be made to develop economical positioning systems. The characteristics of these positioning systems depend mainly on the application considered : the measurement range, the speed and acceleration of the robot, the outdoor conditions vary greatly from one application to the other. From our experience, we consider that this complex problem can be solved under laboratory conditions by many existing systems including stereo vision and other sophisticated techniques. As far as construction site conditions are considered and the economical constraints are taken into account, nearly none of these existing solutions is suitable. Our approach is to consider together the construction process and the autonomous robot system. The advantage is that the complex pozitioning problem cnri ho split. in two pilrt.~ : - one is transfered to the construction process, whore special equipmcnts participdtirig in the positioning can be integrated with non significant extra-cost regarding to nowaday construction techniques ;