This paper proposes a new hand-guiding robot system for assembly-line work which is targeting an instrument panel installation work in a final assembly process at automobile factories. The robot in the system transfers a heavy/large panel module to nearby a target vehicle body on a carrier line, and helps a worker to assemble it to the moving body, by following worker's operation. The system automatically transforms the 3D orientation of the robot to the body on the line, so that, the worker can assemble only with adjusting position of the panel. The proposed assist method enables to reduce operation time and to make assembling tolerance wider. The effectiveness and performance of the assembling are confirmed by several experiments.
