DESIGN, DYNAMICS, CONTROL AND DEVELOPMENT OF WALL-CLIMBING ROBOT

Abstract

Periodic maintenance and safety evaluation of high-rise structures/buildings is very much essential to minimize the impact of the disaster, which often results in loss of life and property. Safety evaluation of structures is carried out through periodic inspection, maintenance, and dynamic analysis of structures. These evaluation techniques are carried out manually, even in very risky structural situations. In addition to the remote inspection, conventional maintenance of buildings/structures for painting/cleaning is required for a clean, safe, healthy, and eco friendly life. The periodic inspection of the high-rise structures and cleaning of building façade is a challenging issue worldwide. In this thesis, two types of wall-climbing robots have been developed and discussed in-depth. It is found from the analysis and laboratory testing that the pneumatic and magnetic adhesion mechanisms are suitable for developing high payload carrying wall-climbing robots for cleaning and inspection tasks. Firstly, a wall-climbing robot based on coupled magnetic wheel and arm-type locomotion mechanisms has been developed for ferrous structures. The developed robot consists of two mobile modules connected with a robot arm mechanism. The actuation of the robot arm is inspired by inchworm locomotion, particularly during wall-to-wall transitions, obstacle avoidance, and uneven surface locomotion. Easiness in the interchanging of wheel to arm and vice versa makes the robot more effective compared to previously developed wall-climbing robots. The kinematic and dynamic model for the proposed coupled wheel and arm locomotion concept has been established. A combination of particle swarm optimization (PSO) and proportional, integral, derivatives (PID) feedback control algorithm has been developed using MATLAB to simulate the different cases of robot motions. The developed prototype of the wall climbing robot is used to verify the coupled wheel and arm locomotion concept in various climbing scenarios. The simulation and experimental findings show good comparisons and validate the model-based design of the wall-climbing robot. Next, the development of a glass façade cleaning robot (GFCR), including its unique design concept, dynamic modelling, and control strategies for efficient coverage path planning, has been presented. The robot design has been conceptualized using mechanisms for adhesion (active and passive), motion, steering, and cleaning. The dynamic model of the robot for vertical glass façade cleaning is derived using Lagrangian formulation. A modified particle swarm optimization (PSO) is used to autotune the proportional, integral, and derivative (PID) parameters for the trajectory tracking simulation and it is more efficient and robust than the standard PSO algorithm. The path planning algorithm using hybrid PID-PSO approach is also developed for energy-efficient coverage of the robot for glass façade cleaning. The coverage algorithm illustrates the energy performance of the GFCR for different paths viz., horizontal line sweep (HLS), vertical line sweep (VLS), spiral line sweep (SLS), and special cell diffusion (SCD) motion. Simulation reveals the robot motion for HLS path is the most energy-efficient. The GFCR model with minimum energy consumption has been validated by working trials. The GFCR has potential applications for cleaning high-rise glass façade buildings and photovoltaic (PV) solar panels. Finally, field trials of these developed robots have also been carried out using various payloads such as sensors for structural inspection and roller brush for glass façade cleaning.