PROJECTS

RADBLAD

A robotic x-ray inspection system for wind turbine blades

The RADBLAD Project (In-Service X-Ray Radiography of Offshore Wind Blades) will develop a robot capable of climbing towers using magnetic adhesion. It will scale turbine towers and x-ray scan blades to discover defects that are not visible on the surface, making pre-emptive repair possible. In order to target and record the surface accurately, it will be capable of sensing blade vibrations and movements and moving its aim in harmony with them.

Phase I of the project was led by innovation experts and data specialists Innvotek in collaboration with the London South Bank Innovation Centre. They are now joined by Forth Engineering, an expert in scale-up of robotic systems; Renewable Advice, a blade inspection specialist; TWI, leaders in non-destructive testing; and ORE Catapult, which will provide world-leading expertise in test and validation for all stages of development and demonstration.

The stages of development will be:

• Scaling up the robot from the current 1:30 scale prototype developed under Phase I
• Testing the inspection system on full-scale ex-service blades (on the ground) to allow its algorithm to learn and perfect its detection of defects
• Developing the robot’s magnetic adhesion and mechanical gait so it can scale a 30-metre training tower
• And demonstrating the full system–climbing robot and x-ray inspection system in an integrated test on representative assets.

This is all working towards a planned test on an onshore turbine, ahead of commercialising the technology for offshore and onshore deployment.

Impacts

Turbine blades are subjected to gusting winds that fatigue the structures and cause them to break down. Around 3,800 blade failures per year are down to failures to inspect and maintain them at an early stage. At present, preventative inspections and maintenance cost between £70,000 and £700,000 per turbine per year. Deploying rope-access technicians to these hazardous locations carries significant health and safety risks too.

The innovation offers a safer way of conducting pre-emptive inspections of offshore wind turbines and provides significantly more information that traditional methods. The radiographic scanner is safe for use around human technicians should they be working in tandem with the robots.

While there is nothing new in radiographic scanning of turbine blades, they currently require dismantling and transporting to a workshop onshore to be inspected. The RADBLAD robot will be the world’s first radiographic inspector capable of conducting its work in situ at the offshore wind farm with minimal turbine downtime (conducting inspections in a few hours instead of 10-days under current radiographic methods).