A magnetically adhering wall climbing wall robot to perform continuous welding of long seams and non destructively test the welds on the hull of a container ship

Abstract

Abstract-- The paper describes the development of a\nwall-climbing robot designed to carry a 7 DOF serial\nlink robot arm of mass 22 kg to a maximum height of\nthirty metres on the outside surfaces of the hull of a\ncontainer ship. The arm has been specially designed to\nperform remote inspection tasks. It deploys ultrasonic\nprobes using force control and task error minimising\ncontrol to perform pulse echo and Time-Of-FlightDiffraction (TOFD) defect detection. The climbing robot is required to move on flat as well as curved surfaces and to step over 40 mm ridges that are formed by welding together steel plates of different thickness. The robot is currently being developed further to\nperform combined welding and monitoring of weld\nquality operations.