Abstract: In order to improve the practicality of the staircase cleaning robot,a staircase cleaning robot with scalable rotating robotic arm was designed,which used the rotation of the robotic arm to go downstairs,and at the same time,a combination of a telescopic rod and a tensioning device was used to achieve the scalable function,improving its adaptability to stairs of different heights. The staircase cleaning robot mainly consists of cleaning structures,scalable downstairs structures,control systems,and other parts. By designing corresponding control strategies for the robot,it can achieve discrimination of stair edge signals,control of downstairs,single-layer stair surface obstacle avoidance,stair end obstacle avoidance,stair kick surface height detection and other functions.The above control strategies were executed alternately to achieve the robot's cleaning of the entire stair surface. The scalable experiment of the robotic arm shows that the robotic arm can extend and shorten to different lengths (24~29 cm). The experiment of going downstairs with different heights shows that the robot can adapt to stairs with different heights between 10~20 cm,and the success rate of going downstairs is 100 %. The experiment of stair kick surface height detection shows that the robot can adjust the appropriate length of the robotic arm based on the height of the stair kick surface.

Key words: staircase cleaning, robot, scalable robotic arm, going downstairs, control system