Offshore wind turbine blades are subjected to one of the harshest environments on Earth: the extreme weather out at sea can erode and damage their composite surfaces over time. Ensuring blades have longer lifetimes at sea is down to regular, pre-emptive inspection and maintenance, where each blade surface is scanned for defects and resurfaced while the damage is at an early stage.
At present, this work is conducted by rope-access technicians and spans tens of thousands of blades in UK waters alone that are often hard and risky to access. As the wind industry pushes turbines into ever deeper and more remote waters in support of the UK’s Net Zero goals, the danger, difficulty, downtime and expense are set to increase.
Blade inspection and repair is just one of the immense tasks that London SME BladeBUG is setting out to transform through robotic, digitalised solutions. Inspection of lightning strike protection and the condition of bolts, the vital fasteners that hold wind turbine structures together, are the latest applications for their ground-breaking technology.
During collaborative projects, funded by Innovate UK and executed in collaboration with the Offshore Renewable Energy (ORE) Catapult, BladeBUG has developed and trialled a robotic platform that will be capable of not only blade inspection and repair, but ultrasonic bolt inspection (utilising technology from EchoBolt Ltd) and lightning protection too.
Under the first project (2017-2018), the company’s prototype of a hexapod blade crawling robot had its capabilities tested and it design evolved to ensure the maximum results from the smallest and simplest platform. Trials were conducted at ORE Catapult’s National Renewable Energy Centre in Blyth and demonstrated that this first version of the technology was capable of securely gripping all areas of a blade.
With the first iteration of the robot complete and the basic concept proven, a second stage of development commenced in 2019 and ran up to February 2021. The platform progressed to trials at ORE Catapult’s 7MW Levenmouth Demonstration Turbine in Fife to prove its ability to work on a working offshore wind turbine in real-world conditions. It achieved the world’s first robotic blade walk, securing a historic milestone in robotic innovation and proving that a robot can be responsive enough to navigate an offshore wind turbine in the same way as a human. Here, it also demonstrated its ability to scan blade surfaces for defects.
From 2020, the company has been developing the robot’s ability to also conduct non-destructive testing of blade surfaces and repair defects that it detects.
In parallel, the technology was made available to another ground-breaking Innovate UK project that was led by ORE Catapult – MIMRee (Multi-Platform Inspection, Maintenance and Repair in Extreme Environments) in order to assist a team of academics and technology developers in creating the mission planning software and components of a fully end-to-end robotics inspection and repair mission. This scenario involved a moving-blade inspection from a camera on an autonomous vessel (developed by Thales) and a blade crawler being deployed by drone from the deck.
In April to September 2021, the BladeBUG platform was put through its paces with a series of robustness test and trials. The robot conducted remote tests of the lightning protection system at an offshore wind turbine (ORE Catapult’s Levenmouth Demonstration Turbine), performing a series of checks and tasks beyond the visual line of sight.
During this time multiple NDT tools were also further developed, integrated and tested within the BladeBUG robot, validating its ability to operate as a multifunctional tool.
An ongoing development is a collaboration with EchoBolt, a company that had previously developed an ultrasonic bolt inspection device under a separate project with ORE Catapult and Innovate UK. Like BladeBUG, this technology addresses a routine task at offshore wind farms that is of immense scale and is often beset by risks, delays and difficulties of access when conducted manually (using hydraulic wrenches).
The EchoBolt technology allows technicians to scan bolts using a small handheld ultrasonic device for loss of torque (eliminating the need to manually untighten and retighten each one). Using the BladeBUG platform as a vehicle, the solution will allow for less human intervention, more frequent pre-emptive inspection and less costly operations.
GE Renewable Energy is supporting in an advisory role on this project which is expected to unlock a 75% saving on bolt maintenance and repair bills with a potential market of £150 million a year within a decade.
As such, it is an outstanding example of two technology pioneers coming together to find new applications and markets for their technologies.
With the first set of inspection tools integrated into the BladeBUG platform, a development project focusing on leading-edge repair began in April 2021. Leading-edge erosion can reduce the aerodynamic performance of turbine blade by up to 2.5% and is a critical task in maintenance cycles.
The robot will be equipment with sanding and cleaning tools to prepare the surface. This work centred on refining the leading edge walking of the robot, and support from ORE Catapult to investigate efficacy of leading-edge coatings.
Since its launch, the BladeBUG team has grown to ten full-time staff members that are based at its central London workshop. In the coming year, the company expects to hire a further 4 full-time employees in roles as diverse as engineering, programming, marketing communications and field services.
The company is regularly featured in the media, including the BBC’s 39 Ways to Save the Planet, national newspapers and the renewables sectoral media where they champion the need for smart operations and maintenance in the wind industry, including the adoption of robotics, artificial intelligence and digitalisation.
The company regularly attends industry events to share learning from its projects with the wider innovation community, such as the KTN Robotics & AI Industry Showcase in the summer of 2021.
As part of this business growth journey, they have participated in the Imperial Enterprise Lab and ORE Catapult’s Launch Academy.
With a history of strong technology development behind them and a growing reputation in the offshore wind industry, BladeBUG is now set for the final step towards commercialisation of its products and services.