Analytical modelling of suction cups used for window-cleaning robots

This paper presents a new analytical modelling of suction cups used for window-cleaning robots. The modelling can be used when the force is parallel to the base surface of the suction cup. The basic idea of this analytical modelling is that the active area of suction cup will decrease as the air pressure decreases in the suction cup. The analytical modelling is based on the theory of elasticity. The results indicated that the suction force should be calculated by means of multiplying the air pressure by the active area of the suction cup rather than the bottom area that is commonly used in traditional methods, and that the friction between the suction cup and the surface of window glass could also be calculated. Finally, the results obtained by the analytical modelling were verified and compared with those calculated by the traditional method.