Vibration suppression of omni-directional mobile robots for inspecting outdoor infrastructure facilities (Construction of evaluation system for vibration properties)

Abstract

Infrastructure facilities have been deteriorating and require a vast number of inspections conducted by skilled engineers. Inspection robots are now necessary because of a shortage of skilled engineers. To improve the inspection efficiency of outdoor infrastructure facilities, we investigated an omni-directional mobile robot that can move freely in all directions. However, it is necessary to design a vibration-isolation mechanism because the positional-inspection accuracy of underground objects is adversely affected by vibration in an outdoor environment. We constructed an experimental setup to evaluate the vibration properties of the robot’s wheel and evaluated the acceleration characteristics due to the difference between the direction of movement and speed of the wheel. Experiments using the omni-wheel as the robot’s wheel were performed. We clarified that the input vibration is transmitted to the robot body by the wheel. We also compared the experimental results and theoretical estimation and confirmed that vibration generated from the wheel could be estimated using the formula for calculating the period of vibration. In consideration of the external environment and vibration properties such as the irregularities of the road surface and the structure of wheel, we confirmed that it is possible to estimate input vibration in the upper housing of the wheel.