Figure 6 shows the scene that the PI is moving along the frame of window, and Fig. 7 shows the view of the mechanism around suction cup and wheels. The pilot experiment confirmed the mobility of Pl on a perpendicular glass surface at O.06[m/s] in average. However, the reproducible stable mobility is not achieved.
Problems and factors are enumerated below.
Vacuum is destroyed and a robot cannot adsorb on the surface of window by the gap produced by decentering of drive wheels or inequality on surface of drive wheels, since there is no suspension mechanism for adjusting the contact forces of suction cup and wheels toward the glass.
The vibrations of stepping motors influence the absorption of robot.
The torque of stepping motor par mass is weak. Considering above problems we tried to design new prototype P2. Next chapter shows the analysis of adsorption and the design of P2.