A coating system including a coating robot and a movable opener robot. The coating robot has a fixed base fixedly mounted to a coating booth, and a first arm rotatably coupled to the fixed base about a first axis substantially parallel to a conveyance direction of a workpiece that includes a body and a first movable member. The body has a body inner surface and the first movable member has a first movable member inner surface. The movable opener robot has a movable base mounted such that the movable opener robot is movable in the coating booth in the conveyance direction. The movable base is mounted below the fixed base. The movable opener robot can open the first movable member of the workpiece. The coating robot can coat the body inner surface and the first movable member inner surface when the first movable member has been opened.