Tracked-wheel crawler robot for vertically aligned mooring chain climbing design, simulation and validation of a climbing robot for mooring chains

Abstract

Only a few attempts have been made to investigate the possibilities of developing chain climbing robot due to the complexity of the structure and physical nature of chain links. Mooring chains are subjected to large tidal waves, harsh environmental conditions and storms on a daily basis. Therefore, periodic inspection of the integrity of chain links is important. Work reported in this paper investigates the possibilities of mooring chain climbing by using tracked wheel locomotion. The permanent magnet adhesion, tracked wheel crawler robot developed for this purpose can climb on mooring chains both in air and underwater with a variable speed according to the inspection requirements (maximum speed of 42cm/minute). It is able to handle an external downward force of 50N during the climbing motion. Numerical modelling based analysis of a magnet adhesion module and the strength of the robot structure is validated with prototyping and testing of the concept.

Mooring chain climbing robot for NDT inspection applications

“…A tracked wheel crawler robot, Figure 1c, uses a system of tracked wheels and magnetic adhesion to move along misaligned chain links [6]. While preliminary testing yielded positive results, the robot required further work to prevent slippage under loading and during the transitions between links [7], [8]. The "PANDORA" project, Figure 1d, aimed to produce a system to conduct chain cleaning and inspection tasks using an autonomous underwater vehicle (AUV).…”

Adaptable legged-magnetic adhesion tracked wheel robotic platform for misaligned mooring chain climbing and inspection

“…The primary purpose of the presented robotic platform is to convey NDT equipment along the chain to perform an inspection. The preliminary design of the proposed robotic platform was previously published by the current authors in (Dissanayake, et al, 2018) and (Dissanayake, et al, 2017). This paper describes an upgraded version of the robotic platform which solves the climbing problem posed by link misalignment of mooring chains.…”