Auto-Cleaning Wall-climbing Robot System

It is tedious, dangerous and awkward to clean the facades of skyscrapers. Even to present, all the work is done by workers in suspended scaffoldings. It is quite urgent to realize the automation of fa?ade cleaning. Two key technique questions should be solved in the cleaning automation process. They are wall-moving technique and wall-cleaning technique.The Auto-cleaning Wall-climbing Robot System discussed in this dissertation is supported by "863" National High -tech Plan, aiming at providing city construction industry with a highly efficient wall-climbing robot for cleaning glass or tile wall automatically. In this dissertation, the moving system, suction system, cleaning system, sewage recycling system, control system are studied with reference to relevant research works.Guided by my tutors Prof. Gong Z.B. and associate Prof. Tan S.L., based on lots of reference, this paper presents the classification and features of wall-climbing robot and introduces the development situation of wall-climbing robot and wall cleaning technique in detail. With considerations of both techniques and practical application, we discussed the technical difficulties in developing the Auto-cleaning Wall-climbing Robot System. Then the dissertation presents a prototype model. The system includes a single-suction cup wheel-moving type wall-climbing robot which worked as mobile platform and working platform, a combined cleaning device which can flush, scrub, scrape the wall surface and be able to collect sewage automatically, and a control system which was installed on the wall-climbing robot directly. The whole system can bemanipulated by up-computer or hand-holding control-box remotely.The wall-climbing robot makes the whole system stick and move on the surface. It consists of suction system and moving system. The moving system combines non-rail sling driving mode and omni-directional wheel driving mode together. A new type of omni-directional wheel, which have three functions: driving, turning and overstepping, had developed. Four sets of this kind of omni-directional wheel consist the mobile platform of the wall-climbing robot, which makes the whole system move on the wall surface freely.To solve the suction and sealing problem on the wall surface, the air spring made of spring and air cell is designed as the sealing mechanism. The sealing mechanism can adapt to different kinds of wall surface such as tile surface or concrete surface. On the basis of flow net theory, the suction models while the air pump starts and stops suddenly or the suction cup encounters obstacles are established. The effect between pressure inside the suction cup and structure parameter of suction is studied. Then some rules for design this kind of suction cup are discussed in detail.A reasonable designed cleaning device is necessary for implementing the cleaning task. A multi-functions cleaning apparatus is designed. This apparatus combined the flushing, scrubbing and scraping cleaning modes. It is able to collect the sewage so that no sewage leaks from the gap between suction cup and wall surface to pollute the cleaned surface again. The different factors which influence the cleaning effect and efficiency have been studied in detail. Based on this study, the cleaning technology has been programmed.The kinematics and dynamics equations are necessary for the robot control. Because there are multi-closed loops and multiple dot-connect links, the Sheth-Uicher transform is used to build thekinematics equation of wall climbing robot. The positive and inverse solutions of the kinematics equation are gained. These solutions provide the theory support for motion control of the wall-climbing robot. The wheel driven wall-climbing robot is an non-integrity system, Appell equation is used to established the dynamics model of the wall-climbing robot. In fact, a given wheel serves as driving wheel or turning wheel during moving period. Based on this pointed, the dynamics equations for driving wheel and turning wheel are built respectively.The control syst...