Based on the analysis of the characteristics of climbing robot,a new kind of self-scramble robot is proposed ,which will be used for cleaning the spherical surface of the National Grand Theater. The robot consists of the climbing part,the moving part,the cleaning part and the pitching part. A distributed controller based on CAN bus is designed to control the robot,which is mainly composed of singlechips P80C592. The system software is programmed with modularization method. Finally,the motion function is described in details. Experiments have been made with this robot under the real circumstances of the National Grand Theater,and the resuts show that the design principle is rational,and the structure and the control system are reliable.