Development of Sliding Suction Cup based Wall Climbing Robotic System

摘要

Climbing robots normally use suction cups for adhering to the surface. Most of the climbing robots using suction cup employs a remotely located huge suction generator to provide the required negative pressure to the suction cup. The negative suction pressure to the suction cups is delivered through long extendable tube which affects the dynamic balancing and stability of climbing robot. In the proposed work, the climbing robot using suction drag principle is realized with a suction cup integrated with a suction motor and hardware components using an embedded controller, pressure sensors and drive motors, which can move on smooth surfaces. This arrangement provides the required negative suction pressure for cup to adhere to the wall. It also enables to control the cup negative pressure by continuous monitoring. Catia software is used to design, simulation of the suction cup. This paper discusses about its basic mathematical analysis, the simulation of the model and the prototype wall climbing robot. The amount of suction force and corresponding negative suction pressure required by the suction cup system for holding the robot on vertical surface is computed theoretically and simulated using Matlab Simulink. It is observed through simulation that by varying the speed of the suction motor the negative pressure in the suction cup system can be controlled and the simulation result for the complete holding of the suction cup system considering the frictional forces is found to be -10.23 kPa. The simulation is also performed to find the sliding and drop off negative pressure levels by allowing a minimum suction leakage percentage. This is compared with the experimental suction cup system. The experimental results for the negative pressure in the suction cup system is found to be -6.63 kPa for holding the robot weighing 0.2Kg.The climbing robot can be realized by operating the suction cup system with a negative pressure lesser than -6.63 kPa by varying the speed of the suction motor. The drop off negative pressure value of the suction cup system is observed to be -1.82kPa.