An Inflatable Soft Crawling Robot With Nondestructive Testing Capability for Overhead Power Line Inspection

Abstract

This paper presents designing and prototyping of an inflatable soft crawling robot equipped with nondestructive testing (NDT) sensing capability for inspection and diagnosis of potential mechanical faults in overhead power cables. The soft robot is comprised of two gripping modules with radial expansion/contraction, one at the proximal and the other one at the distal end, and a longitudinal contractile-expandable driving module in-between for providing a bi-directional crawling movement. The robot and its soft actuators are made of fabrics and can be wrapped around the power line cables for navigation. The main novelty of the current robotic inspection platform is to integrate the mobility component with an NDT sensing system. Conceptual designs and CAD models of the robot parts, textile-based inflatable structures, and the pneumatic driving mechanisms were developed. The mechanical parts were fabricated using advanced and conventional manufacturing techniques. An Arduino-based electropneumatic control board was developed including proper pneumatic circuits, pumps, sensors, and batteries. The fabricated parts were assembled to create the initial prototype of the soft robot. Control algorithms were developed for the operation of the robot. The prototyped mechanism was tested in a laboratory setting while the collected data were used for modifying the designs, and controlling software and hardware. The feasibility of the proposed robot for cable crawling and multimodal NDT sensing was successfully demonstrated.