Aerial Robotic Systems Drones for Contact-Based Ultrasonic Wall Thickness UT Measurements at Height

Abstract

The use of aerial robotic systems that physically contact oil and gas structural assets to obtain measurement data in offshore and marine environments carries unique challenges and operational variables. The objectives of this paper are to demonstrate, with examples, how these aerial robotic systems afford safer, cheaper, and better nondestructive testing (NDT) measurement collection methodology and allow more robust insight into assets conditions than the slower, less safe, and more expensive manual method. To take NDT measurements such as Ultrasonic Wall Thickness (UT) Measurements at height, currently one needs to utilize a lift, ladders or other solutions to reach areas on certain assets. This can be both dangerous, due to the possibility of falls, and time consuming. Utilizing an aerial robotics platform for contact based (not visual) NDT measurements such as Ultrasonic Thickness (UT) allows workers to remain safely on the ground. Drones, with robotic arms, have the potential to improve inspection, testing and data collection. This paper explores an aerial robotic system that flies up to a structure with a metal sub-straight, then under full autonomous software control, touches a UT measurement probe to the target and records the measurement data compliant with American Petrolium Institute (API) and other standards. The use of aerial robotics systems for NDT is still a new and novel application utilizing existing technologies such as electronic measurement readers, drones, etc. with a system of complex integrations that allows for a better application of science. Aerial Robotic NDT systems have the potential to improve the inspection, testing and data collection aspects of coated and uncoated assets, in part, by making the NDT measurement process easier and safer thus allowing for more frequent measurements and/or a larger quantity of measurement samples. When possible, working at heights should be eliminated as part the hierarchy of fall protection stipulated by both OSHA and ANSI. For this reason alone, the use of aerial robotic systems is important now and in the immediate future Oil & Gas infrastructure, including Offshore. This paper intends to provide readers an awareness of this new technology as well as provide information about its efficacy, limitations and operational requirements.