Abstract
In this paper, a mechanism for overcoming high obstacles is proposed to broaden the application range of the exterior wall cleaning robot. The proposed one-degree-of-freedom wheel mechanism can overcome high obstacles by the rotation of a wheel with two different spoke lengths. To implement the inclined tilted wheel (ITW), two design variables were studied - a spoke assembly angle and a wheel shaft assembly angle. At the critical assembly angles of $\varphi = 45^{\circ }$ and $\theta = 135^{\circ }$ , the characteristics of the generated wheel trajectory does not invade the upper and lower space of the robot. From the trajectory, the space efficiency can be secured for thrust unit cleaning device. And the same contact characteristics can get with the existing wheel on the surface. To secure the orientation stability after overcoming a high obstacle, the reaction force analysis at each caster was performed. Through the analysis results, the orientation stability was secured without the distance compensation at the gantry during or after overcoming obstacles. To verify the obstacle-overcoming ability of the ITW, a 6m - high - test bench and a 0.3m - high - obstacles was manufactured. With a scenario defining an angular position of ITW, the ability of overcoming obstacle was confirmed in the test. In addition, the scenario was supplemented for stable overcoming to avoid a collision against obstacles through additional experiments.
Highlights
Cleaning the exterior walls of buildings is an important task in terms of management annually
Many researchers have been studied about the cleaning robot in order to replace humans in building exteriorwall cleaning sites [1,2,3,4,5,6,7,8,9]
The most well-known robots are TITO 500[10], IPC EAGLE [11], SKYPRO [11], SIRIUSc [12], and Sky Scraper -I [13] that move via ropes fixed with a winch system on the building tops
Summary
Cleaning the exterior walls of buildings is an important task in terms of management annually. Until the short spoke return to the initial position (until - 0°), the rear wheel rotates, as shown in Fig. 5 b) After overcoming the obstacle, an angle φ is generated between the rope and the wall. When it is larger than a critical angle, the robot becomes unstable. Under the practical conditions, such as the vibration and inertia force by winch, the maximum angle is about 10°.In consideration of the robot layout and the relation between the obstacle height and distance from the gantry, the variables are determined as d = 15 mm and φ = 4°. Since the thruster rotates at a high speed, a separate control device and power supply were used during the experiments for the thruster unit
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
